Molecular characterization of human astrovirus infection in children under 5 years of age with acute gastroenteritis in Tehran, Iran, 2021-2022: co-infection with rotavirus.

Human astroviruses (HAstVs) are considered important causative pathogens of acute gastroenteritis (AGE) in children under 5 years of age worldwide, along with group A rotavirus (RVA), norovirus (NoV), and enteric adenovirus (EAdV). The present study was aimed to both detect HAstV and its co-infections and investigate genetic analysis of circulating HAstV and co-infected virus in hospitalized children under 5 years of age with AGE in Iran. Accordingly, a sum of 200 stool specimens were screened by PCR for HAstV during 2021-2022. The HAstV was found in 0.5% of 200 specimens (n = 1) while was co-infected with RVA. The genetic and phylogenetic analysis indicated HAstV1 genotype, which clustered with viruses from lineage 1b, which has not been previously reported in Iran. The detected RVA strain belonged to G1 lineage II/P[8]-lineage III, which has been reported previously in Iran as the most common strain. The further genetic analysis of RVA VP6 and NSP4 demonstrated an atypical genotype pattern G1P[8]-I1-E2, as a mono-reassortant of a Wa-like genogroup, which appeared to be reassorted with the NSP4 gene of E2 genotype of the G2P[4] DS-1 genogroup. Although the clinical outcomes of the AGE-causing viruses co-infection is not yet entirely clear, it seems that future studies will be helpful to merge clinical and epidemiological data of co-infecting viruses for a more accurate medical and clinical relevance in symptomatic children.

Co-administration of rotavirus nanospheres VP6 and NSP4 proteins enhanced the anti-NSP4 humoral responses in immunized mice.

Inconveniences associated with the efficacy and safety of the World Health Organization (WHO) approved/prequalified live attenuated rotavirus (RV) vaccines, sounded for finding alternative non-replicating modals and proper RV antigens (Ags). Herein, we report the development of a RV candidate vaccine based on the combination of RV VP6 nanospheres (S) and NSP4112-175 proteins (VP6S + NSP4). Self-assembled VP6S protein was produced in insect cells. Analyses by western blotting and transmission electron microscopy (TEM) indicated expression of VP6 trimer structures with sizes of ≥140 kDa and presence of VP6S. Four group of mice were immunized (2-dose formulation) intra-peritoneally (IP) by either¨VP6S + NSP4¨ or each protein alone (VP6S or NSP4112-175) emulsified in aluminium hydroxide or control. Results indicated that VP6S + NSP4 formulation induced significant anti-VP6 IgG (P < 0.001) and IgA (P < 0.05) as well as anti-NSP4 IgG (P < 0.001) and enhancement of protective immunity. Analyses of anti-VP6S and anti-NSP4 IgG subclass (IgG1 and IgG2a) showed IgG1/IgG2a ≥6 and IgG1/IgG2a ≥3 ratios, respectively indicating Th2 polarization of immune responses. The combination of VP6S + NSP4 proteins emulsified in aluminum hydroxide adjuvant might present a dual universal, efficient and cost-effective candidate vaccine against RV infection.

Vitamin D and Covid-19: From potential therapeutic effects to unanswered questions.

Evidence suggests that vitamin D supplementation could potentially be effective either in treatment or prevention of coronavirus disease 2019 (Covid-19). Indeed, several studies and trials have begun to investigate the impact of vitamin D supplementation on patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. In this review, we focus on the potential mechanisms of vitamin D in the pathogenesis of Covid-19. We consider whether deficiency of vitamin D may be one of the underlying biological factors that could explain the excess mortality seen among non-Caucasians. We also raise several important questions which need to be addressed to provide a clear picture of the extent to which vitamin D supplementation may benefit patients with Covid-19, particularly those with underlying risk factors.

Illuminating the in vitro effects of Epstein-Barr virus and vitamin D on immune response in multiple sclerosis patients.

Given the complexity of immune complex diseases including multiple sclerosis (MS) and the plausible interactions between different risk factors, delineating the interplay between them would be imperative. The current study aimed to evaluate the in vitro effects of Epstein-Barr virus (EBV) and vitamin D on immune response in MS patients and healthy controls. The status of vitamin D and EBV load was evaluated using multiple techniques. In vitro EBV-infected peripheral blood mononuclear cells (PBMCs), in the presence or absence of vitamin D, were checked for IL-10, IFN-γ, and vitamin D receptor. MS patients showed significantly higher plasma levels of 1,25-(OH)2D but not 25-OHD, increased EBV load, and lower levels of vitamin D receptor (VDR) expression compared with healthy controls. Interestingly, an inverse correlation was observed between VDR expression and EBV load in PBMCs. Indeed, the levels of IFN-γ and IL-10 production were significantly higher in supernatant collected from in vitro EBV-infected PBMCs in MS patients compared with controls. While all vitamin D-treated PBMCs showed reduced levels of IFN-γ production, in vitro treatment of vitamin D showed no influence in IL-10 production. EBV and vitamin D were found to exert opposite in vitro effects on immune dysregulation in these patients. Our results highlight the complex interactions of different risk factors with immune system.

Combined use of lactic-acid-producing bacteria as probiotics and rotavirus vaccine candidates expressing virus-specific proteins.

Due to the lower efficacy of currently approved live attenuated rotavirus (RV) vaccines in developing countries, a new approach to the development of safe mucosally administered live bacterial vectors is being considered, using probiotic bacteria as an efficient delivery platform for heterologous RV antigens. Lactic acid bacteria (LAB), which are considered food-grade bacteria and normal microbiota, have been utilized throughout history as probiotics and developed since the 1990s as a delivery system for recombinant heterologous proteins. Over the last decade, LAB have frequently been used as a platform for the delivery of various RV antigens to the mucosa. Given the appropriate safety profile for neonates and providing the benefits of probiotics, recombinant LAB-based vaccines could potentially address the need for a subunit RV vaccine. The present review focuses mainly on different recombinant LAB vaccine constructs for RV and their potential as an alternative recombinant vaccine against RV disease.

The interplay between vitamin D and viral infections.

The pleiotropic role of vitamin D has been explored over the past decades and there is compelling evidence for an epidemiological association between poor vitamin D status and a variety of diseases. While the potential anti-viral effect of vitamin D has recently been described, the underlying mechanisms by which vitamin D deficiency could contribute to viral disease development remain poorly understood. The possible interactions between viral infections and vitamin D appear to be more complex than previously thought. Recent findings indicate a complex interplay between viral infections and vitamin D, including the induction of anti-viral state, functional immunoregulatory features, interaction with cellular and viral factors, induction of autophagy and apoptosis, and genetic and epigenetic alterations. While crosstalk between vitamin D and intracellular signalling pathways may provide an essential modulatory effect on viral gene transcription, the immunomodulatory effect of vitamin D on viral infections appears to be transient. The interplay between viral infections and vitamin D remains an intriguing concept, and the global imprint that vitamin D can have on the immune signature in the context of viral infections is an area of growing interest.

Rotavirus VP6 as a potential vaccine candidate.

By the age of 5 years, virtually all children have been infected by group A rotavirus (RVA), which is responsible for around half million mortality annually prior to vaccination. Relatively high rate of the morbidity and mortality highlights the necessity of applying preventive procedures particularly in developing countries. Two live attenuated RVA vaccines (Rotarix and RotaTeq) are licensed and now being used in many countries worldwide. Although these vaccines are shown to reduce the mortality up to 50%, several key questions yet remained to answer. Indeed, the licensed RV vaccines were found to be less effective in countries of sub-Saharan Africa and Southeast Asia. Therefore, developing next generation RVA vaccines is warranted. VP6 is highly abundant and conserved protein that forms the middle layer of RV particles and was shown to be both antigenic and immunogenic. Although it does not induce neutralizing antibodies, different VP6 preparations were found to induce homologous and cross-reactive immune responses with partial protection from RVA replication. Although the molecular mechanisms are not fully elucidated, VP6-based RVA vaccine candidates are worthy of further consideration. This review aims to focus on different aspects of VP6 protein and its potentiality for an alternative RV vaccine against RV disease.

Ameliorative role of aspirin in paraquat-induced lung toxicity via mitochondrial mechanisms.

Paraquat (PQ) has accounted for numerous suicide attempts in developing countries. Aspirin (ASA) as an adjuvant treatment in PQ poisoning has an ameliorative role. And, it's uncoupling of mitochondrial oxidative phosphorylation role has been well established. The current study aimed at examining the aspirin mechanism on lung mitochondria of rats exposed to PQ. Male rats were randomly allocated in five groups: Control group, PQ group (50 mg/kg; orally, only on the first day), and PQ + ASA (100, 200, and 400 mg/kg; i.p.) groups for 3 weeks. Mitochondrial indices and respiratory chain-complex activities were determined. PQ induced lung interstitial fibrosis; however, ASA (400 mg/kg) led to decrease in this abnormal alteration. In comparison with PQ group, complex II and IV activity, and adenosine triphosphate content in ASA groups had significantly increased; however, reactive oxygen species production, mitochondrial membrane permeabilization, and mitochondrial swelling were significantly reduced. In conclusion, aspirin can alleviate lung injury induced by PQ poisoning by improving mitochondrial dynamics.

Will Nanotechnology Bring New Hope for Stem Cell Therapy?

The potential of stem cell therapy has been shown in preclinical trials for the treatment of damage and replacement of organs and degenerative diseases. After many years of research, its clinical application is limited. Currently there is not a single stem cell therapy product or procedure. Nanotechnology is an emerging field in medicine and has huge potential due to its unique characteristics such as its size, surface effects, tunnel effects, and quantum size effect. The importance of application of nanotechnology in stem cell technology and cell-based therapies has been recognized. In particular, the effects of nanotopography on stem cell differentiation, proliferation, and adhesion have become an area of intense research in tissue engineering and regenerative medicine. Despite the many opportunities that nanotechnology can create to change the fate of stem cell technology and cell therapies, it poses several risks since some nanomaterials are cytotoxic and can affect the differentiation program of stem cells and their viability. Here we review some of the advances and the prospects of nanotechnology in stem cell research and cell-based therapies and discuss the issues, obstacles, applications, and approaches with the aim of opening new avenues for further research.

Prevalence and genetic diversity of norovirus genogroup II in children less than 5 years of age with acute gastroenteritis in Tehran, Iran.

Viral gastroenteritis is a major public health problem worldwide. In Iran, very limited studies have been performed with regard to the epidemiology of noroviruses. This study aimed to evaluate the prevalence and molecular epidemiology of GII noroviruses in hospitalized children less than 5 years of age with acute gastroenteritis (AGE). A total of 210 stool specimens were collected from Ali Asghar Children's Hospital and Bahrami Children's Hospital in Tehran, from June 2015 to June 2016. The samples were screened by real-time RT-PCR for genogroup II (GII). Positive samples were genotyped by semi-nested PCR followed by Sanger sequencing and phylogenetic analysis. Norovirus was identified in 36 (17.1%) of 210 specimens. Based on genetic analysis of RdRp and capsid sequences, the strains were clustered into eight RdRp-capsid genotypes: GII.P4-GII.4 Sydney_2012 (41.7%), GII.Pe-GII.4 Sydney_2012 (30.6%), GII.P21-GII.3 (13.9%), GII.P16-GII.4 Sydney_2012 (2.8%), GII.P16-GII.12 (2.8%), GII.P2-GII.4 Sydney_2012 (2.8%), GII.P7-GII.7 (2.8%) and GII.P2-GII.2 (2.8%). We determined several different co-circulating norovirus genotypes in children < 5 years of age with AGE in our hospital in Tehran, Iran. Continued molecular surveillance of noroviruses, including typing of both RdRp and capsid genes, is important for monitoring emerging strains in our continued efforts to reduce the overall burden of norovirus disease.

Molecular typing of human herpesvirus 8 among HIV positive in comparison to HIV-negative individuals in Iran.

It is still unclear whether different HHV-8 genotypes may have different pathogenic and tumorigenic properties associated with a diverse rate of disease progression. In some areas where genotype C was found to be prominent among classic KS patients, genotype A was shown to be more frequent among AIDS-associated KS patients. Genotype C was previously reported to be widespread in Iran, with genotype A being less frequent among patients with classic KS although no data are available with regards to the HHV-8 genotyping among Iranian HIV-infected patients. In order to analyze HHV-8 genotypes (ORF K1), six HIV-infected patients (with or without KS), and 22 HIV-negative subjects (classic/iatrogenic KS patients and IVDUs) were investigated using nested PCR. Genotype A was detected more frequently among HIV-infected patients with or without KS (three out of six) whereas genotype C was found more common among HIV-negative subjects including classic/iatrogenic KS patients and IVDSs (21 out of 22), and this difference was statistically significant (P = 0.044). In conclusion, our data further support the dominancy of HHV-8 genotype C in Iranian general population. Moreover, genotype A was more common among HIV-infected patients with or without KS. J. Med. Virol. 89:703-709, 2017. © 2016 Wiley Periodicals, Inc.

Multiple sclerosis-associated retrovirus, Epstein-Barr virus, and vitamin D status in patients with relapsing remitting multiple sclerosis.

The relationship between infections and autoimmune diseases is complex and there are several reports highlighting the role of human endogenous retroviruses (HERVs) in these patients. The levels of multiple sclerosis-associated retrovirus (MSRV)-type DNA of Env gene was measured in peripheral blood mononuclear cells from 52 patients with relapsing-remitting multiple sclerosis (RRMS) and 40 healthy controls using specific quantitative PCR (qPCR) analysis. Furthermore, we analyzed the status of HERV-W/MSRV in these patients with regards to both EBV (DNA load and anti-EBNA1 IgG antibody) and vitamin D concentration. MSRV DNA copy number were significantly higher in RRMS patients than healthy controls (P < 0.0001). Interestingly, an inverse correlation was found between MSRV DNA copy number and serum vitamin D concentration (P < 0.01), but not for EBV load or anti-EBNA-1 IgG antibody.

MDM2 gene polymorphisms and risk of classic Kaposi's sarcoma among Iranian patients.

A single-nucleotide polymorphism (SNP) in the promoter region of MDM2 (SNP309T>G, rs2279744) has been shown to increase the expression of the MDM2 protein in various cancer types. However, only one study has analyzed the role of the MDM2 polymorphism in the development of Kaposi's sarcoma (KS). The association of MDM2 SNP309 with classic KS risk was evaluated in 79 Iranian patients with classic KS and 123 healthy controls. The MDM2 SNP309 was genotyped using PCR and restriction fragment length polymorphism methods. No significant correlation was found between the SNP309 polymorphism in MDM2 promoter and classic KS risk. There was no significant correlation between gender and disease stage. However, a significant association was found between SNP309 GG genotype and younger age (≤50 years) (odds ratio 9.5, 95% confidence intervals 1.5-60, p = 0.03). Our findings support no major role for the MDM2 SNP309 in KS development although it might influence the clinical outcome of KS in younger patients.

Epidemiological and clinical characteristics of scorpionism in Shiraz (2012-2016); development of a clinical severity grading for Iranian scorpion envenomation.

Background: Scorpionism is a public health problem in some provinces in Iran. The present study aimed to assess the clinical manifestations of scorpion envenomation in Shiraz and determine a clinical severity grading for Iranian scorpion envenomation in order to suggest a treatment guideline for emergency physicians. Methods: In this analytic retrospective study, all medical charts of patients with scorpion sting admitted in the adult medical toxicology center in Shiraz during July 2012 to July 2016 were assessed. Data regarding the patient's age, gender, sting site, month of envenomation, time of sting, clinical manifestations, vital signs, presence of blood or hemoglobin in urine analysis, duration of admission, color of scorpion, received treatments, and administration of scorpion antivenin were recorded. Results: The scorpions in Shiraz and its suburban area were classified into two groups: yellow scorpions ( Mesobuthus eupeus, Mesobuthus caucasicus , and Compsobuthus matthiesseni) and Hottentotta scorpions (Hottentotta jayakari and Hottentotta zagrosensis). A total of 126 cases of scorpion stings were assessed. About 59% (n=74) were males. The patients aged 8-63 years (mean age, 33.8±11.5 years). About 38.4% (n=48) of the stings occurred during summer. More than 40% of patients (n=51) referred to the emergency department (ED) at night. Localized pain was the most frequent presenting complaint (76.2%). The most frequent general symptom was nausea (6.3%). The most prevalent envenomation site was the lower extremities followed by upper extremities (43.5% and 41.9%, respectively). Based on the clinical severity grading for Iranian scorpion envenomation, 65, 43, and 18 patients (51.6%, 34.1%, and 14.3%) were classified in the grades I, II, and III, respectively. Eighty-one (73%) patients stayed in the ED from 1 to 6 hours, and 30 (27%) patients stayed for >6 hours for observation. Severe localized pain was more prevalent in stings with Hottentotta scorpions than yellow scorpions (P=0.01). The season of envenomation with Hottentotta scorpions was summer in all cases, but envenomation with yellow scorpions was seen throughout the year. All patients received symptomatic treatment, and five were given scorpion antivenin. No death was reported. Conclusion:Hottentotta jayakari is recommended to be listed among the medically important scorpions in Iran. Moreover, scorpion-stung patients in geographical regions where Hemiscorpius lepturus and Androctonus crassicauda are not prevalent may be treated in outpatient departments. The presented grading system can be used for treating patients with scorpion envenomation.

First report of human parvovirus 4 detection in Iran.

Parvovirus 4 (PARV4) is an emerging and intriguing virus that currently received many attentions. High prevalence of PARV4 infection in high-risk groups such as HIV infected patients highlights the potential clinical outcomes that this virus might have. Molecular techniques were used to determine both the presence and the genotype of circulating PARV4 on previously collected serum samples from 133 HIV infected patients and 120 healthy blood donors. Nested PCR was applied to assess the presence of PARV4 DNA genome in both groups. PARV4 DNA was detected in 35.3% of HIV infected patients compared to 16.6% healthy donors. To genetically characterize the PARV4 genotype in these groups, positive samples were randomly selected and subjected for sequencing and phylogenetic analysis. All PARV4 sequences were found to be genotype 1 and clustered with the reference sequences of PARV4 genotype 1. J. Med. Virol. 88:1314-1318, 2016. © 2016 Wiley Periodicals, Inc.

EBV and vitamin D status in relapsing-remitting multiple sclerosis patients with a unique cytokine signature.

Multiple sclerosis, a debilitating autoimmune and inflammatory disease of the central nervous system, is associated with both infectious and non-infectious factors. We investigated the role of EBV infection, vitamin D level, and cytokine signature in MS patients. Molecular and serological assays were used to investigate immune biomarkers, vitamin D level, and EBV status in 83 patients with relapsing-remitting multiple sclerosis and 62 healthy controls. In total, 98.8 % of MS patients showed a history of EBV exposure compared to 88.6 % in the healthy group (p = 0.005). EBV DNA load was significantly higher in MS patients than healthy subjects (p < 0.0001). Using a panel of biomarkers, we found a distinct transcriptional signature in MS patients compared to the healthy group with mRNA levels of CD73, IL-6, IL-23, IFN-γ, TNF-α, IL-15, IL-28, and IL-17 significantly elevated in MS patients (p < 0.0001). In contrast, the mRNA levels for TGF-ß, IDO, S1PR1, IL-10, and CCL-3 were significantly lower in MS patients compared to healthy controls (p < 0.0001). No significant differences were found with the mRNA levels of IL-13, CCL-5, and FOXP3. Interestingly, in MS patients we found an inverse correlation between vitamin D concentration and EBV load, but not EBNA-1 IgG antibody levels. Our data highlight biomarker correlates in MS patients together with a complex interplay between EBV replication and vitamin D levels.

Thoughts on the current management of acute aluminum phosphide toxicity and proposals for therapy: An Evidence-based review.

The majority of aluminum phosphide (ALP) toxicity cases are suicidal attempts. Despite advances in critical care medicine, the mortality rate of ALP remains very high. Unfortunately, knowledge on the toxicokinetics of ALP is very low. An obsolete idea was proposed that inhibition of complex IV of cytochrome C oxidase is responsible for multiorgan dysfunction. However, based on human studies, this effect might be insignificant. Thus, a novel idea proposes that the main mechanism might be vascular wall integrity disruption. The low frequency of acute toxicity and unanswered questions about the toxicokinetics and toxicodynamics has led to leaden advances of novel treatments. The aim of this review was to evaluate problems regarding current treatment protocols and propose new ideas based on updated information. For this purpose, we reviewed all available articles on the management of ALP poisoning published to date. Considering failure of conventional therapies on maintaining systolic blood pressure, correcting acid-base disturbances, and support cardiac function, the previous treatment protocols have been overruled. However, repudiate of conventional treatments in this deadly condition is not without penalties for the health-care provider. The introduction of new therapies including refuse of gastric lavage with water-soluble compounds, administration of a high molecular weight colloidal solution for fluid resuscitation and termination using sodium bicarbonate, and vasoactive agents has been prospected to improve patient survival. This protocol is in early clinical evaluation; nevertheless, it appears to improve patient's survival; hence, future randomized trials should be performed to support their effectiveness.

Successful management of zinc phosphide poisoning.

Zinc phosphide (Zn2P3) rodenticide, is generally misused intentionally for suicidal purpose in Iran. For many years, scientists believe that liberation of phosphine (PH3) on contact with acidic content of the stomach is responsible for clinical presentations. However, relatively long time interval between ingestion of Zn2P3 and presentation of its systemic toxicity, and progression of acute liver failure could not be explained by the current opinion. Hence, an innovative theory intended that phosphonium, as an intermediate product will create and pass through the stomach, which then will reduce to produce PH3in the luminal tract. Here, we present a case of massive Zn2P3 poisoning. In our case, we used repeated doses of castor oil to induce bowel movement with an aim of removing unabsorbed toxin, which was proved by radiography. Interestingly, the patient presents only mild symptoms of toxicity such as transient metabolic acidosis and hepatic dysfunction.

Mitochondrial haplogroups and control region polymorphisms in Kaposi's sarcoma patients.

Inflammation and reactive oxygen species (ROS) production have recently considered as key mechanisms in the pathogenesis of Kaposi's sarcoma (KS). Since mitochondria are the major source of ROS production, this organelle may play a main role in KS development. However, there are no studies on mtDNA variations and haplogroups in this area. The focus of this study was to investigate the mtDNA variants and haplogroups in KS patients and their relationship to tumor development. To address this, we have genotyped mtDNA in 45 Iranian KS patients and 48 age and sex-matched Iranian controls. A strong positive correlation was observed between UK cluster and decreased risk of KS. Our results suggest that the UK cluster might be a protective haplogroup for KS development. It is probably superhaplogroup UK, with lower ATP and ROS production, may prevent KSHV reactivation from latent to lytic phase that is essential for KS development.

Intra-peritoneal and intra-rectal immunogenicity induced by rotavirus virus like particles 2/6/7 in mice.

We previously developed virus like particles of rotavirus (RV) with VP2, VP6, and VP7 proteins (VLP2/6/7) using stable High-five cell line. To evaluate the immunogenicity of our construct, we assessed the humoral and cytokine responses induced by VLP2/6/7 in BALB/c mice immunized intra-peritoneally and intra-rectally. Enzyme-linked immunosorbent assay (ELISA) and Relative quantitative (RQ) Real-time PCR were used to evaluate the antibody (IgG and IgA) levels in serum and mRNA levels of IL-6, IL-10 and IFN-γ in spleen cells, respectively. Our results showed that VLP2/6/7 is capable of intra-peritoneal (I.P.) and intra-rectal (I.R.) induction of serum IgG and IgA responses. IgA was detected in fecal samples of immunization groups by I.P. and I.R. routes. Interestingly, I.R. route induced higher IgA titer compared with I.P. route which was statistically significant. Moreover, mRNA levels of IL-6 and IFN-γ were significantly elevated in mice immunized intra-peritoneally with VLP2/6/7 compared to control group. As such, the mean change was 7.4 (P < 0.05) and 14.8 (P < 0.001) for IFN-γ and IL-6, respectively. Likewise, the same pattern was found when mice were immunized intra-rectally. Although elevated, the difference in the mean change for IL-10 was not statistically significant when compared to control group. Our findings indicated that VLPs constructed via a stable insect cell line are able to induce both humoral and cellular responses, a similar pattern as observed after immunization with live RVs.