Role of viruses in periodontitis:An extensive review of herpesviruses,human immunodeficiency virus,coronavirus-19,papillomavirus and hepatitis viruses

Periodontitis is the inflammation of the supporting structures around the dentition.Several microbial agents,mostly bacteria,have been identified as causative factors for periodontal disease.On the other hand,oral cavity is a rich reservoir for viruses since it contains a wide variety of cell types that can be targeted by viruses.Traditionally,the focus of research about the oral flora has been on bacteria because the most widespread oral diseases,like periodontitis and dental caries,are outcomes of bacterial infection.However,recently and especially after the emergence of coronavirus disease 2019,there is a growing tendency toward including viruses also into the scope of oral microbiome investigations.The global high prevalence of periodontitis and viral infections may point out to a concomitant or synergistic effect between the two.Although the exact nature of the mechanism still is not clearly understood,this could be speculated through the manipulation of the immune system by viruses;hence facilitating the furthermore colonization of the oral tissues by bacteria.This review provides an extensive and detailed update on the role of the most common viruses including herpes family(herpes simplex,varicella-zoster,Epstein-Barr,cytomegalovirus),Human papillomaviruses,Human immunodeficiency virus and severe acute respiratory syndrome coronavirus 2 in the initiation,progression and prognosis of periodontitis.

Herpes simplex keratitis:A brief clinical overview

The aim of our minireview is to provide a brief overview of the diagnosis,clinical aspects,treatment options,management,and current literature available regarding herpes simplex keratitis(HSK).This type of corneal viral infection is caused by the herpes simplex virus(HSV),which can affect several tissues,including the cornea.One significant aspect of HSK is its potential to cause recurrent episodes of inflammation and damage to the cornea.After the initial infection,the HSV can establish a latent infection in the trigeminal ganglion,a nerve cluster near the eye.The virus may remain dormant for extended periods.Periodic reactivation of the virus can occur,leading to recurrent episodes of HSK.Factors triggering reactivation include stress,illness,immunosuppression,or trauma.Recurrent episodes can manifest in different clinical patterns,ranging from mild epithelial involvement to more severe stromal or endothelial disease.The severity and frequency of recurrences vary among individuals.Severe cases of HSK,especially those involving the stroma and leading to scarring,can result in vision impairment or even blindness in extreme cases.The cornea's clarity is crucial for good vision,and scarring can compromise this,potentially leading to visual impairment.The management of HSK involves not only treating acute episodes but also implementing long-term strategies to prevent recurrences and attempt repairs of corneal nerve endings via neurotization.Antiviral medications,such as oral Acyclovir or topical Ganciclovir,may be prescribed for prophylaxis.The immune response to the virus can contribute to corneal damage.Inflammation,caused by the body's attempt to control the infection,may inadvertently harm the corneal tissues.Clinicians should be informed about triggers and advised on measures to minimize the risk of reactivation.In summary,the recurrent nature of HSK underscores the importance of both acute and long-term management strategies to preserve corneal health and maintain optimal visual function.

Interleukin 1βreceptor and synaptic dysfunction in recurrent brain infection with Herpes simplex virus type-1

Several experimental evidence suggests a link between brain Herpes simplex virus type-1 infection and the occurrence of Alzheimer’s disease.However,the molecular mechanisms underlying this association are not completely understood.Among the molecular mediators of synaptic and cognitive dysfunction occurring after Herpes simplex virus type-1 infection and reactivation in the brain neuroinflammatory cytokines seem to occupy a central role.Here,we specifically reviewed literature reports dealing with the impact of neuroinflammation on synaptic dysfunction observed after recurrent Herpes simplex virus type-1 reactivation in the brain,highlighting the role of interleukins and,in particular,interleukin 1βas a possible target against Herpes simplex virus type-1-induced neuronal dysfunctions.

Recurrent herpes infection showing a new facial phenotype:A case report

BACKGROUND Facial herpes is a common form of the herpes simplex virus-1 infection and usually presents as vesicles near the mouth,nose,and periocular sites.In contrast,we observed a new facial symptom of herpes on the entire face without vesicles.CASE SUMMARY A 33-year-old woman with a history of varicella infection and shingles since an early age presented with sarcoidosis of the entire face and neuralgia without oral lesions.The patient was prescribed antiviral treatment with valacyclovir and acyclovir cream.One day after drug administration,facial skin lesions and neurological pain improved.Herpes simplex without oral blisters can easily be misdiagnosed as pimples upon visual examination in an outpatient clinic.CONCLUSION As acute herpes simplex is accompanied by neuralgia,prompt diagnosis and prescription are necessary,considering the pathological history and health conditions.

Herpes Simplex Virus Encephalitis Complicated by Acute Ischemic Stroke

Introduction: Herpes simplex virus is the most common etiology for life-threatening sporadic encephalitis worldwide. Antiviral therapy with acyclovir has been shown to reduce mortality and should be started promptly in patients with clinically suspected viral encephalitis before serological confirmation of the diagnosis. Despite antiviral treatment, it is associated with significant mortality and a wide range of neurologic sequelae or neuropsychiatric disorders. Clinical presentation includes fever, headache, altered mental status, and focal or generalized seizures. In some cases, it can present with focal neurological deficits, such as an acute stroke. The aim of this study is to identify rare complications of HSVE. Presentation: We present a case of a 71-year-old female patient with herpes virus encephalitis and an ischemic cerebral accident. The findings of CT scan of the brain revealed an extensive right temporal hypodensity. CSF findings include an elevated protein level, normal glucose level and pleocytosis with lymphocyte predominance. The lumbar tap confirmed the presence of herpes simplex virus type 1 with polymerase chain reaction (PCR) in the CSF. Neurological manifestations include focal neurological deficit with left-sided hemiparesis and coma. After 40 days of complex therapy, an improvement in the mental state was observed. Conclusion: There are varying degrees of neurologic sequelae among survivors in children and adults despite the antiviral treatment. Herpes simplex encephalitis has significant morbidity and high mortality due to the lack of prophylactic treatment and preventable strategies.

Contributions of neurotropic human herpesviruses herpes simplex virus 1 and human herpesvirus 6 to neurodegenerative disease pathology

Human herpesviruses （HVs） have developed ingenious mechanisms that enable them to traverse the defenses of the central nervous system （CNS）. The ability of HVs to enter a state of latency, a defining char- acteristic of this viral family, allows them to persist in the human host indefinitely. As such, HVs represent the most frequently detected pathogens in the brain. Under constant immune pressure, these infections are largely asymptomatic in healthy hosts. However, many neurotropic HVs have been directly connected with CNS pathology in the context of other stressors and genetic risk factors. In this review, we discuss the potential mechanisms by which neurotropic HVs contribute to neurodegenerative disease （NDD） patholo- gy by highlighting two prominent members of the HV family, herpes simplex virus 1 （HSV-1） and human herpesvirus 6 （HHV-6）. We （i） introduce the infectious pathways and replicative cycles of HSV-1 and HHV-6 and then （ii） review the clinical evidence supporting associations between these viruses and the NDDs Alzheimer＇s disease （AD） and multiple sclerosis （MS）, respectively. We then （iii） highlight and dis- cuss potential mechanisms by which these viruses exert negative effects on neurons and glia. Finally, we （iv） discuss how these viruses could interact with other disease-modifying factors to contribute to the initiation and/or progression of NDDs.

Herpes Simplex Viruses and Induction of Interferon Responses

Herpes simplex viruses （HSV） are human pathogens responsible for a variety of diseases, including localized mucocutaneous lesions, encephalitis, and disseminated diseases. HSV infection leads to rapid induction of innate immune responses. A critical part of this host response is the type I IFN system including the induction of type I IFNs, IFN-mediated signaling and amplification of IFN response. This provides the host with immediate countermeasure during acute infection to limit initial viral replication and to facilitate an appropriate adaptive immune response. However, HSV has devised multiple strategies to evade and interfere with innate immunity This review will focus on the induction of type I IFN response by HSV during acute infection and current knowledge of mechanisms by which HSV interferes with this induction process.

Autoimmune complications and clinical outcomes of herpes simplex encephalitis in children: A case series

Objective:To report the neurologic prognosis and autoimmune complications of 16 cases of childhood herpes simplex virus encephalitis.Methods:The study was conducted atŞanlıurfa Training and Research Hospital,Turkey from June 2017 to August 2019.The study included 16 pediatric patients aged between 6 months and 17 years(median age 77.7 months)who were diagnosed with herpes simplex virus type 1 encephalitis by pediatric infectious disease and pediatric neurology clinics.Patients were followed using patient records,and interviews at the pediatric neurology clinic or via the telephone.Clinical and demographic data,received therapies,neurologic prognosis and complications were evaluated.Results:Patients with and without autoimmune encephalitis were compared in terms of age,sex,symptom duration before treatment,initial cerebrospinal fluid protein,glucose,red blood count and white blood count but no significant difference was found.Autoimmune complications were seen in four patients.N-methyl-D-aspartate encephalitis was observed in three patients and choreoathetosis was seen in one patient.The average follow-up period was 48.3 months.Twenty-five percent of the patients were receiving multiple antiepileptic drug(AED)treatment,43.8%were receiving single AED treatment and 31.3%were not receiving AED treatment at the end of the follow-up.Motor disability was observed in 12.5%and drug-resistant epilepsy was observed in 6.3%who had autoimmune complications.Conclusions:Seizures and movement disorders were controlled with immunotherapy and autoantibodies should be studied routinely.Treatment should be started early upon recognition of autoimmune complications through follow-up by measuring autoantibody levels and clinical examination results.Effective prevention and curative treatment modalities are needed to avoid herpes simplex virus encephalitis complications.

Antiviral activity of mangiferin from the rhizome of Anemarrhena asphodeloides against herpes simplex virus type 1

Objective:To evaluate the antiviral activity of pure compounds against herpes simplex virus type 1(HSV-1)from the rhizome of Anemarrhena asphodeloides.Methods:Bioassay-guided isolation was conducted to separate the active compound and its chemical structure was elucidated by spectral analysis.In vitro antiviral efficacy of active compound was detected by Cell Counting Kit-8 assay,plaque reduction assay,and fluorescence observation.RT-PCR was used to determine the viral load and the cytokine-related gene expression after HSV-1 infection.In vivo study was also conducted to further determine antiviral efficacy of an active compound against HSV-1.Results:An active compound was isolated and elucidated as mangiferin.Mangiferin significantly inhibited the replication of HSV-1 in Vero cells with a half maximal inhibitory concentration(IC_(50))of 64.0 mg/L.Time-of-addition and time-of-removal assays demonstrated that mangiferin could effectively inhibit the replication of HSV-1 in the early stage(8 h).UL12,UL42,and UL54 gene expression levels of HSV-1 in the 64 mg/L mangiferin-treated group were markedly reduced as compared with the HSV-1 group(P<0.01).Fluorescence observation showed that mangiferin attenuated the mitochondrial damage maintainingΔΨm induced by HSV-1 in Vero cells.The expression of inflammatory factors TNF-α,IL-1β,and IL-6 was remarkably increased in the virus-infected group as compared with that in the normal group(P<0.05),the levels of these inflammatory factors dropped after treatment with mangiferin.Mangiferin significantly decreased the viral load and attenuated the HSV-1-induced up-regulation of TNF-α,IL-1β,and IL-6.The relative protection rate of HSV-1-infected mice could reach up to55.5%when the concentration of mangiferin was 4 g/kg.Conclusions:Mangiferin exhibits promising antiviral activity against HSV-1 in vitro and in vivo and could be a potential antiviral agent for HSV-1.

Novel Functional Motifs of the Cell Entry Glycoprotein D for Oncolytic Herpes Simplex Viruses

Background: Oncolytic herpes simplex virus (oHSV) have been proved effective and safe to treat tumors. Glycoprotein D (gD) has been engineered for targeting cancer cells and de-targeting normal cells successfully, however, the effectiveness and safety of oHSVs still need to be improved. Method: Here we sequenced the DNA encoding gD of our recently isolated new strain HSV-1-LXMW and compared the gD amino acid sequence with the gDs of other 7 HSV-1 and 3 HSV-2 strains. Results: Phylogenetic analysis revealed that HSV-1-LXMW is evolutionarily close to HSV-1-Patton and -KOS strains. The gD amino acid sequence alignment identified 19 conserved and 8 variable regions. We further predicted 10 new motifs in HSV gD for the first time and identified motif differences in HSV-1 and HSV-2. We summarized the gD-engineered oHSVs and found that some of the newly identified gD motifs are actually functional. Conclusion: Our results shed light on HSV gD biology and provided new directions for future gD functional studies and engineering in order to make better oHSVs.

Streptococcus pneumoniae and Herpes Simplex Virus-1 Central Nervous System Co-Infection

Co-infections of the central nervous system (CNS) caused by bacterial and viral pathogens are considered to be rare. Herpes simplex virus type-1 (HSV-1) reactivation following Streptococcus pneumoniae infection is well described but most cases are related to oral or cutaneous lesions or in respiratory samples. HSV-1 CNS reactivation after Streptococcus pneumoniae meningitis is a very rare event and may have significant morbidity and mortality. In this case report, we describe a 71-year-old female patient that presented with a history of abdominal pain and confusion/disorientation that had tonic-clonic seizures while in the Emergency Department. The diagnostic work-up confirmed CNS co-infection caused by Streptococcus pneumoniae and HSV-1. Of note, beyond age, the patient had no known risk factors for both entities and recovered fully after antibiotic and antiviral therapy. This case underlines that clinicians must be aware of CNS co-infection despite being a rare diagnosis. This should be suspected particularly in patients who present an unusual clinical course of CNS infection.

A Meta-Analysis on the Correlation Between Herpes Simplex Virus Type II Infection and Adverse Pregnancy Outcomes in China

Objective:To systematically evaluate the relationship between herpes simplex virus type II(HSV-2)infection in pregnant women and the adverse pregnancy outcomes(preterm delivery,spontaneous abortion,stillbirth,monstrum,low birth weight,intrauterine growth retardation,premature rupture of membranes),so as to provide clinical guidance for the prevention and treatment of adverse pregnancy outcomes caused by HSV-2 infection in pregnant women.Methods:2140 articles were collected from PubMed,China National Knowledge Infrastructure(CNKI),and other databases for the past 20 years.According to the inclusion criteria,the literatures about the relationship between HSV-2 infection of pregnant women and adverse pregnancy outcomes were screened.The effect model was determined by heterogeneity test results,and the meta-analysis was carried out by RevMan 5.3 software.Results:The results of meta-analysis showed that the positive rate of HSV-2 was higher in the adverse pregnancy group than in the control group(odds ratio[OR]:7.92,95%confidence interval[Cl]:3.91-16.01),and the difference was statistically significant.Conclusion:HSV-2 infection will increase the risk of adverse pregnancy outcomes.Prevention and effective control of HSV-2 infection in early pregnancy can reduce the rate of adverse pregnancy outcome,which is of great significance to the promotion of eugenics.

Viruses and autism: A Bi-mutual cause and effect

Autism spectrum disorder(ASD)is a group of heterogeneous,multi-factorial,neurodevelopmental disorders resulting from genetic and environmental factors interplay.Infection is a significant trigger of autism,especially during the critical developmental period.There is a strong interplay between the viral infection as a trigger and a result of ASD.We aim to highlight the mutual relationship between autism and viruses.We performed a thorough literature review and included 158 research in this review.Most of the literature agreed on the possible effects of the viral infection during the critical period of development on the risk of developing autism,especially for specific viral infections such as Rubella,Cytomegalovirus,Herpes Simplex virus,Varicella Zoster Virus,Influenza virus,Zika virus,and severe acute respiratory syndrome coronavirus 2.Viral infection directly infects the brain,triggers immune activation,induces epigenetic changes,and raises the risks of having a child with autism.At the same time,there is some evidence of increased risk of infection,including viral infections in children with autism,due to lots of factors.There is an increased risk of developing autism with a specific viral infection during the early developmental period and an increased risk of viral infections in children with autism.In addition,children with autism are at increased risk of infection,including viruses.Every effort should be made to prevent maternal and early-life infections and reduce the risk of autism.Immune modulation of children with autism should be considered to reduce the risk of infection.

Management strategies for common viral infections in pediatric renal transplant recipients

Viral infections have been considered as a major cause of morbidity and mortality after kidney transplantation in pediatric cohort.Children are at high risk of acquiring virus-related complications due to immunological immaturity and the enhanced alloreactivity risk that led to maintenance of high immunosuppressive regimes.Hence,prevention,early detection,and prompt treatment of such infections are of paramount importance.Among all viral infections,herpes viruses(herpes simplex virus,varicella zoster virus,Epstein-Barr virus,cytomegalovirus),hepatitis B and C viruses,BK polyomavirus,and respiratory viruses(respiratory syncytial virus,parainfluenza virus,influenza virus and adenovirus)are common in kidney transplant recipients.These viruses can cause systemic disease or allograft dysfunction affecting the clinical outcome.Recent advances in technology and antiviral therapy have improved management strategies in screening,monitoring,adoption of prophylactic or preemptive therapy and precise treatment in the immunocompromised host,with significant impact on the outcome.This review discusses the etiology,screening and monitoring,diagnosis,prevention,and treatment of common viral infections in pediatric renal transplant recipients.

Possible viral agents to consider in the differential diagnosis of blepharoconjunctivitis

BACKGROUND Blepharoconjunctivitis poses a diagnostic challenge due to its diverse etiology,including viral infections.Blepharoconjunctivits can be acute or chronic,selflimiting,or needing medical therapy.AIM To review possible viral agents crucial for accurate differential diagnosis in cases of blepharoconjunctivitis.METHODS The PubMed database was searched for records relating to viral blepharoconjunctivitis.The search string generated was“("virally"[All Fields]OR"virals"[All Fields]OR"virology"[MeSH Terms]OR"virology"[All Fields]OR"viral"[All Fields])AND"Blepharoconjunctivitis"[All Fields]".RESULTS A total of 24 publications were generated from the search string.Reference lists from each relevant article were also searched for more information and included in this review.Viral etiologies such as adenovirus,herpes simplex virus(HSV),varicella-zoster virus(VZV),and Epstein-Barr virus(EBV)are frequently implicated.Adenoviral infections manifest with follicular conjunctivitis and preauricular lymphadenopathy,often presenting as epidemic keratoconjunctivitis.HSV and VZV infections can result in herpetic keratitis and may exhibit characteristic dendritic corneal ulcers.EBV,although less common,can cause unilateral or bilateral follicular conjunctivitis,particularly in immunocompromised individuals.Other potential viral agents,such as enteroviruses and molluscum contagiosum virus,should also be considered,especially in pediatric cases.CONCLUSION Prompt recognition of these viral etiologies is essential for appropriate management and prevention of complications.Thus,a thorough understanding of the clinical presentation,epidemiology,and diagnostic modalities is crucial for accurate identification and management of viral blepharoconjunctivitis.

New strategies against drug resistance to herpes simplex virus

Herpes simplex virus （HSV）, a member of the Herpesviridae family, is a significant human pathogen that results in mucocutaneous lesions in the oral cavity or genital infections. Acyclovir （ACV） and related nucleoside analogues can successfully treat HSV infections, but the emergence of drug resistance to ACV has created a barrier for the treatment of HSV infections, especially in immunocompromised patients. There is an urgent need to explore new and effective tactics to circumvent drug resistance to HSV. This review summarises the current strategies in the development of new targets （the DNA helicase/primase （H/P） complex）, new types of molecules （nature products） and new antiviral mechanisms （lethal mutagenesis of Janus-type nucleosides） to fight the drug resistance of HSV.

In vitro Anti-viral Activity of the Total Alkaloids from Tripterygium hypoglaucum against Herpes Simplex Virus Type 1

Herpes simplex virus type 1 （HSV-1） is a commonly occurring human pathogen worldwide. There is an urgent need to discover and develop new alternative agents for the management of HSV-1 infection. Tripterygium hypoglaucum （level） Hutch （Celastraceae） is a traditional Chinese medicine plant with many pharmacological activities such as anti-inflammation, anti-tumor and antifertility. The usual medicinal part is the roots which contain about a 1% yield of alkaloids. A crude total alkaloids extract was prepared from the roots of T. hypoglaucum amd its antiviral activity against HSV-1 in Vero cells was evaluated by cytopathic effect （CPE） assay, plaque reduction assay and by RT-PCR analysis. The alkaloids extract presented low cytotoxicity （CC50 = 46.6μg/mL） and potent CPE inhibition activity, the 50% inhibitory concentration （ICs0） was 6.5 μg/mL, noticeably lower than that of Acyclovir （15.4μg /mL）. Plaque formation was significantly reduced by the alkaloids extract at concentrations of 6.25 μg/mL to 12.5 μg/mL, the plaque reduction ratio reached 55% to 75% which was 35% higher than that of Acyclovir at the same concentration. RT-PCR analysis showed that, the transcription of two important delayed early genes UL30 and UL39, and a late gene US6 of HSV-1 genome all were suppressed by the alkaloids extract, the expression inhibiting efficacy compared to the control was 74.6% （UL30）, 70.9% （UL39） and 62.6% （US6） respectively at the working concentration of 12.5μg/mL. The above results suggest a potent anti-HSV-1 activity of the alkaloids extract in vitro.

Ribosome Inactivating Proteins from Plants Inhibiting Viruses

Many plants contain ribosome inactivating proteins (RIPs) with N-glycosidase activity, which depurinate large ribosomal RNA and arrest protein synthesis. RIPs so far tested inhibit replication of mRNA as well as DNA viruses and these proteins, isolated from plants, are found to be effective against a broad range of viruses such as human immunodeficiency virus (HIV), hepatitis B virus (HBV) and herpes simplex virus (HSV). Most of the research work related to RIPs has been focused on antiviral activity against HIV; however, the exact mechanism of antiviral activity is still not clear. The mechanism of antiviral activity was thought to follow inactivation of the host cell ribosome, leading to inhibition of viral protein translation and host cell death. Enzymatic activity of RIPs is not limited to depurination of the large rRNA, in addition they can depurinate viral DNA as well as RNA. Recently, Phase I/II clinical trials have demonstrated the potential use of RIPs for treating patients with HIV disease. The aim of this review is to focus on various RIPs from plants associated with anti-HIV activity.

The Herpes Simplex Virus Type 1 Multiple Function Protein ICP27

The herpes simplex virus type 1 （HSV-1） infected-cell protein 27 （ICP27） is an essential, highly conserved protein involved in various steps of HSV-1 gene regulation as well as in the shut-off of host gene expression during infection. It functions primarily at the post-transcriptional level in inhibiting precursor mRNA splicing and in promoting nuclear export of viral transcripts. Recently, many novel functions performed by the HSV- 1 ICP27 protein were shown, including leptomycin B resistance, inhibition of the type I interferon signaling, regulation of the viral mRNA translation and determining the composition of HSV-1 virions

Asymptomatic seminal infection of herpes simplex virus:impact on male infertility

In more than half of infertile men, the cause of their infertility is unknown. Several studies revealed the role of viral infections in male infertility. The aim of the present study was to determine the prevalence of herpes simplex virus-1 （HSV-1） and HSV-2 in semen from asymptomatic infertile male patients, and its association with altered semen parameters. A total of 70 semen samples were collected from infertile men who attended the Research and Clinical Center for Infertility in Yazd, Iran. Semen analysis and diagnostic real-time PCR using specific primers and probes for HSV-1 and HSV-2 DNA were performed. Comparison of semen parameters between virally in- fected and non-infected samples were performed with independent t-test and Mann-Whitney test. Semen analysis showed that infertile men fell into two groups, the male factor group and the unexplained group. HSV-1 and HSV-2 DNA was detected in 16 （22.9%） and 10 （14.3%） of 70 semen samples, respectively. All HSV-positive samples had abnormal semen parameters （the male factor group）. Although HSV infection was not associated with sperm motility and morphological defects, it was correlated with lower sperm count in the seminal fluid. The findings suggest that asymptomatic seminal infection of HSV plays an important role in male infertility by adversely af- fecting sperm count.