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Baculoviruses have been extensively studied for their potential in microbial pest control, but the mechanisms behind their mode of action still need to be addressed. Here we report differential expression of a cellular miRNA, Sfr-miR-184, from Sf9 cells in response to Autographa californica multicapsid Nucleopolyhedrovirus (AcMNPV) infection. Our results showed that Sfr-miR-184 is down-regulated in AcMNPV-infected cells but not with UV-inactivated virus. Prohibitin gene was determined as a target of the miRNA, which was up-regulated following AcMNPV infection. Using synthetic miRNA mimic, we found that oversupply of the miRNA resulted in decreased transcript levels of the target gene. Results suggest that Sfr-miR-184 negatively regulate prohibitin transcripts in the host cells. Antibody-mediated inhibition and silencing of the prohibitin gene revealed significant reductions in virus DNA replication suggesting a possible role for prohibitin in the virus-host interaction. These findings highlight another molecular mechanism used by baculovirus to manipulate host cells for its replication.
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MicroRNAs , Nucleopoliedrovírus , Proibitinas , Spodoptera , Animais , MicroRNAs/genética , MicroRNAs/metabolismo , Spodoptera/virologia , Células Sf9 , Nucleopoliedrovírus/fisiologia , Replicação Viral , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Baculoviridae/genética , Baculoviridae/fisiologia , Interações Hospedeiro-PatógenoRESUMO
BACKGROUND: Wolbachia are widespread intracellular bacteria in insects that often have high rates of spread due to their impact on insect reproduction. These bacteria may also affect the mating behavior of their host with impacts on the fitness of host progeny. In this study, we investigated the impact of Wolbachia on a preference for mating with young or old males in the parasitoid wasp Habrobracon hebetor. RESULTS: Our results showed that uninfected females from a tetracycline-treated line preferred to mate with young males, whereas Wolbachia-infected females had no preference. Time to mating was relatively shorter in the infected lines. Regardless of Wolbachia infection status, progeny resulting from matings with young males showed higher fitness than those from crosses with old males, and infected females crossed with infected young males showed the highest performance. CONCLUSION: These results suggest an impact of Wolbachia on female mate preference and offspring fitness although it is unclear how this phenomenon increases Wolbachia transmission of infected wasps. © 2024 Society of Chemical Industry.
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DNA methylation is an epigenetic process that involves the chemical modification of DNA, leading to the regulation of its transcriptional activity. It is primarily known for the addition of methyl groups to cytosine in DNA. The whitefly Bemisia tabaci is a polyphagous pest insect and a vector that is responsible for transmitting numerous plant viruses, resulting in significant economic losses in agricultural crops globally. In our study, we characterized the expression of two key DNA methylation genes, the DNA methyltransferases Dnmt1 and Dnmt3, in B. tabaci. Additionally, we explored the impact of inhibiting DNMTs on the miRNA pathway and fitness of whitefly. To investigate the role of the DNA methylation pathway in B. tabaci, we found that the expression of Dnmt1 and Dnmt3 varied across different tissues and developmental stages of B. tabaci. We employed azacytidine (5-AZA) treatment of adults to inhibit DNMTs (DNMT1 and DNMT3). Administration of 5-AZA affected the survival and reproduction of this pest. Moreover, inhibition of DNMTs led to a decrease in the expression of the miRNA pathway core genes Dicer1 and Argonaute1, which subsequently resulted in reduced expression of Let-7 and miR-184 which are essential microRNAs in the physiology and biology of insects. The study suggests that DNA methyltransferases could be targeted for developing an inhibition strategy to control this pest and vector insect.
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Metilação de DNA , Hemípteros , MicroRNAs , Animais , Hemípteros/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Azacitidina/farmacologia , DNA (Citosina-5-)-Metiltransferases/metabolismo , DNA (Citosina-5-)-Metiltransferases/genética , Proteínas de Insetos/metabolismo , Proteínas de Insetos/genética , FemininoRESUMO
BACKGROUND AND AIM: Different Salmonella serotypes are considered one of the most important food pathogens in the world. Poultry meat and eggs are the primary carriers of Salmonella in human populations. This study aimed to estimate the Salmonella enteritidis and Salmonella typhimurium contamination rates of retail hen and quail eggs in Karaj, Iran. Moreover, the antimicrobial resistance patterns of the strains were evaluated, and the efficiency of the standard culture method and multiplex polymerase chain reaction (m-PCR) were compared. MATERIALS AND METHODS: In this descriptive cross-sectional study over 1 year (Jan-Dec 2022), 150 commercial and 150 backyard hen eggs and 300 commercial quail eggs, without cracks and fractures, were collected randomly from best selling groceries in Karaj city. All samples were examined for Salmonella contamination independently by standard culture and m-PCR approaches. A standard disc diffusion method was employed to assess the antimicrobial susceptibility of the strains against 18 antimicrobial agents. RESULTS: Out of 300 examined eggs, 2 S. enteritidis strains were isolated from the shell of backyard hen eggs. The same serotype was also detected in the contents of one of these two eggs. One S. typhimurium was isolated from the shell of a commercial hen egg. Overall, the Salmonella contamination of the shell and contents was 1% and 0.3%, respectively. Salmonella was not isolated from the eggshells or the contents of the quail eggs. There was complete agreement between the results of m-PCR and the standard culture methods. Among the 18 tested antibiotics, the highest resistance was recorded for colistin (100%), followed by nalidixic acid (75%). CONCLUSION: As most Salmonella spp. are associated with human food poisoning, continuous surveillance is required to effectively reduce the risk posed by contaminated poultry eggs. Furthermore, mandatory monitoring of antimicrobial use on Iranian poultry farms is recommended.
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Galinhas , Ovos , Salmonella enteritidis , Salmonella typhimurium , Animais , Irã (Geográfico)/epidemiologia , Salmonella enteritidis/efeitos dos fármacos , Salmonella enteritidis/isolamento & purificação , Ovos/microbiologia , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/isolamento & purificação , Estudos Transversais , Prevalência , Antibacterianos/farmacologia , Codorniz/microbiologia , Farmacorresistência Bacteriana , Doenças das Aves Domésticas/microbiologia , Doenças das Aves Domésticas/epidemiologia , Salmonelose Animal/microbiologia , Salmonelose Animal/epidemiologiaRESUMO
Background: We conducted a phase III, non-inferiority trial comparing safety and efficacy of RCP recombinant spike protein Covid-19 vaccine to BBIBP (Sinopharm). Methods: Adult Iranian population received RCP or BBIBP in a randomized, double blind and an additional non-randomized open labeled trial arms. Eligible participants signed a written informed consent and received two intramuscular injections three weeks apart. In the randomized arm, an intranasal dose of vaccine or adjuvant-only preparation were given to the RCP and BBIBP recipients at day 51 respectively. Participants were actively followed for up to 4 months for safety and efficacy outcomes. Primary outcome was PCR + symptomatic Covid-19 disease two weeks after the second dose. The non-inferiority margin was 10% of reported BBIBP vaccine efficacy (HR = 1.36). Results: We recruited 23,110 participants (7224 in the randomized and 15,886 in the non-randomized arm). We observed 604 primary outcome events during 4 months of active follow-up including 121 and 133 in the randomized and 157 and 193 cases in the non-randomized arms among recipients of RCP and BBIBP respectively. Adjusted hazard ratios for the primary outcome in those receiving RCP compared with BBIBP interval were 0.91 (0.71-1.16) and 0.62 (0.49-0.77) in the randomized and non-randomized arms respectively. The upper boundary of 99.1% confidence interval of HR = 0.91 (0.67-1.22) remained below the margin of non-inferiority in the randomized arm after observing the early stopping rules using O'Brien Fleming method. Conclusion: Our study showed that the RCP efficacy is non-inferior and its safety profile is comparable to the BBIBP.
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BACKGROUND: The immunity induced by primary vaccination is effective against COVID-19; however, booster vaccines are needed to maintain vaccine-induced immunity and improve protection against emerging variants. Heterologous boosting is believed to result in more robust immune responses. This study investigated the safety and immunogenicity of the Razi Cov Pars vaccine (RCP) as a heterologous booster dose in people primed with Beijing Bio-Institute of Biological Products Coronavirus Vaccine (BBIBP-CorV). METHODS: We conducted a randomized, double-blind, active-controlled trial in adults aged 18 and over primarily vaccinated with BBIBP-CorV, an inactivated SARS-CoV-2 vaccine. Eligible participants were randomly assigned (1:1) to receive a booster dose of RCP or BBIBP-CorV vaccines. The primary outcome was neutralizing antibody activity measured by a conventional virus neutralization test (cVNT). The secondary efficacy outcomes included specific IgG antibodies against SARS-CoV-2 spike (S1 and receptor-binding domain, RBD) antigens and cell-mediated immunity. We measured humoral antibody responses at 2 weeks (in all participants) and 3 and 6 months (a subgroup of 101 participants) after the booster dose injection. The secondary safety outcomes were solicited and unsolicited immediate, local, and systemic adverse reactions. RESULTS: We recruited 483 eligible participants between December 7, 2021, and January 13, 2022. The mean age was 51.9 years, and 68.1% were men. Neutralizing antibody titers increased about 3 (geometric mean fold increase, GMFI = 2.77, 95% CI 2.26-3.39) and 21 (GMFI = 21.51, 95% CI 16.35-28.32) times compared to the baseline in the BBIBP-CorV and the RCP vaccine groups. Geometric mean ratios (GMR) and 95% CI for serum neutralizing antibody titers for RCP compared with BBIBP-CorV on days 14, 90, and 180 were 6.81 (5.32-8.72), 1.77 (1.15-2.72), and 2.37 (1.62-3.47) respectively. We observed a similar pattern for specific antibody responses against S1 and RBD. We detected a rise in gamma interferon (IFN-γ), tumor necrosis factor (TNF-α), and interleukin 2 (IL-2) following stimulation with S antigen, particularly in the RCP group, and the flow cytometry examination showed an increase in the percentage of CD3 + /CD8 + lymphocytes. RCP and BBIBP-CorV had similar safety profiles; we identified no vaccine-related or unrelated deaths. CONCLUSIONS: BBIBP-CorV and RCP vaccines as booster doses are safe and provide a strong immune response that is more robust when the RCP vaccine is used. Heterologous vaccines are preferred as booster doses. TRIAL REGISTRATION: This study was registered with the Iranian Registry of Clinical Trial at www.irct.ir , IRCT20201214049709N4. Registered 29 November 2021.
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Vacinas contra COVID-19 , Glicoproteína da Espícula de Coronavírus , Vacinas de Produtos Inativados , Adulto , Masculino , Humanos , Adolescente , Pessoa de Meia-Idade , Feminino , Vacinas contra COVID-19/efeitos adversos , Irã (Geográfico) , Anticorpos Neutralizantes , Anticorpos AntiviraisRESUMO
Following pathogen infection in a host, extensive changes occur in the host's gene expression pattern to suppress infection and increase the chance of host survival. Likewise, many pathogens have evolved to evade/suppress host immunity and increase their survival within the host. In this study, we assessed the NF-κB (Imd and Toll) essential gene expression response of Helicoverpa armigera to an entomopathogenic Serratia marcescens and non-pathogenic Escherichia coli. Bacterial cells of S. marcescens or E. coli were injected into the haemocoel of fifth-instar larvae of H. armigera, whereas distilled water was injected into control insects. Our results showed that the expression levels of the Imd and Toll pathway genes (i.e., Relish, imd, spätzle and dif) and the antimicrobial peptides (i.e., gloverin, transferin, gallerimycin, and galiomicin) were differentially expressed following the bacterial injections while control larvae showed no differences. The E. coli injection induced higher and longer-lasted gene expression than the S. marcescens injected larvae, in which the gene expressions were diminished from 24 h post injection. Transcript Knockdown of Relish increased the replication rates of S. marcescens and E. coli, and lowered the infected larvae survival rates. These results showed that H. armigera NF-κB immunity pathways (particularly Imd pathway) play a vital role in immunity against bacterial infections, and S. marcescens might modulate these pathways to survive and replicate in the host.
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Helicoverpa armigera , NF-kappa B , Animais , NF-kappa B/genética , NF-kappa B/metabolismo , Escherichia coli/fisiologia , Larva/microbiologia , Imunidade , Imunidade InataRESUMO
BACKGROUND: This study explores the safety and immunogenicity of the Razi-Cov-Pars (RCP) SARS Cov-2 recombinant spike protein vaccine. METHOD: In a randomized, double-blind, placebo-controlled trial, adults aged 18-70 were randomly allocated to receive selected 10 µg/200 µl vaccine strengths or placebo (adjuvant). It included two intramuscular injections at days 0 and 21, followed by an intranasal dose at day 51. Immediate and delayed solicited local and systemic adverse reactions after each dose up to a week, and specific IgG antibodies against SARS Cov-2 spike antigens two weeks after the 2nd dose were assessed as primary outcomes. Secondary safety outcomes were abnormal laboratory findings and medically attended adverse events (MAAE) over six months follow up. Secondary immunogenicity outcomes were neutralizing antibody activity and cell-mediated immune response. RESULT: Between May 27th and July 15th, 2021, 500 participants were enrolled. Participants' mean (SD) age was 37.8 (9.0), and 67.0 % were male. No immediate adverse reaction was observed following the intervention. All solicited local and systemic adverse events were moderate (Grade I-II). Specific IgG antibody response against S antigen in the vaccine group was 5.28 times (95 %CI: 4.02-6.94) the placebo group with a 75 % seroconversion rate. During six months of follow-up, 8 SAEs were reported, unrelated to the study intervention. The participants sustained their acquired humoral responses at the end of the sixth month. The vaccine predominantly resulted in T-helper 1 cell-mediated immunity, CD8+ cytotoxic T-cell increase, and no increase in inflammatory IL-6 cytokine. CONCLUSION: RCP vaccine is safe and creates strong and durable humoral and cellular immunity. TRIAL REGISTRATION: (IRCT20201214049709N2).
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COVID-19 , Síndrome Respiratória Aguda Grave , Vacinas , Adulto , Humanos , Masculino , Feminino , Vacinas contra COVID-19/efeitos adversos , COVID-19/prevenção & controle , Anticorpos Neutralizantes , Imunoglobulina G , Método Duplo-Cego , Imunogenicidade da Vacina , Anticorpos AntiviraisRESUMO
Newcastle disease virus (NDV) is considered one of the most devastating avian viral patho-gens affecting the avian population, and it causes a significant economic burden on the poultry industry worldwide. The study aimed to gain deeper understanding of the molecular and phylogenetic analyses of the complete hemagglutinin-neuraminidase (HN) coding region among NDV isolates. The samples were obtained from different parts of Iran from July 2017 to February 2020, were used for phylogenic analysis in this study. The results confirmed the predominance of sub-genotype VII.1.1, previously known as sub-genotype VIIL, which is circulating in commercial broiler farms of Iran. Identification of (a) an additional N-glycosylation site (NIS) at position 144; (b) mutations S315P and I369V which are related to increasing the viral thermostability; (C) cysteine residues at positions 123; (d) amino acid substitutions in the HN antigenic sites, especially the mutations I514V and E347Q, as well as the other mutant within HN binding sites of the VII.1.1 sub-genotype, suggests the idea that this new sub-genotype of NDV may possess a high level of pathogenicity and virulence compared to other NDV sub-genotypes. In conclusion, the results indicate the presence of an additional NIS at position 144, which may alter the virulence of the isolates. Furthermore, the presence of the thermostable mutations (S315P and I369V) and the other amino acid substitutions among the VII.1.1 sub-genotype isolates may have an impact on the vaccine immunity against this new NDV sub-genotype.
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Objectives: This study aimed to determine the safety and immunogenicity of a combined intramuscular/intranasal recombinant spike protein COVID-19 vaccine (RCP). Methods: We conducted a randomized, double-blind, placebo-controlled, phase I trial. Three vaccine strengths were compared with an adjuvant-only preparation. It included two intramuscular and a third intranasal dose. Eligible participants were followed for adverse reactions. Specific IgG, secretory IgA, neutralizing antibodies, and cell-mediated immunity were assessed. Results: A total of 153 participants were enrolled (13 sentinels, 120 randomized, 20 non-randomized open-labeled for IgA assessment). No related serious adverse event was observed. The geometric mean ratios (GMRs) and 95% CI for serum neutralizing antibodies compared with placebo two weeks after the second injection were 5.82 (1.46-23.13), 11.12 (2.74-45.09), and 20.70 (5.05-84.76) in 5, 10, and 20 µg vaccine groups, respectively. The GMR for anti-RBD IgA in mucosal fluid two weeks after the intranasal dose was 23.27 (21.27-25.45) in the 10 µg vaccine group. The humoral responses were sustained for up to five months. All vaccine strengths indicated a strong T-helper 1 response. Conclusion: RCP is safe and creates strong and durable humoral and cellular immunity and good mucosal immune response in its 10 µg /200 µL vaccine strengths. Trial registration: IRCT20201214049709N1.
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BACKGROUND: Application of insect growth regulators (IGR) is a good option for insect pest management because of their fewer adverse effects on humans and domestic animals. These compounds are capable of interfering with normal growth and development by mimicking the actions of hormones such as juvenile hormone (JH) or ecdysone. The effect of JH and its analogs on some aspects of insect immunity has been determined, yet their possible effects on antiviral immunity response has not been investigated yet. Considering the importance of antiviral response in viral replication, in this study the effects of the JH analog (JHA), fenoxycarb on the antiviral immunity pathway core genes [i.e. micro (mi)RNA, small interfering (si)RNA and apoptosis] of Helicoverpa armigera (Hubner) larvae were investigated. The effect of fenoxycarb on the susceptibility of the larvae to H. armigera nuclear polyhedrosis virus (HaNPV) also was assessed. RESULTS: The results showed that the transcription level of miRNA (Dicer1, Ago1), siRNA (Dicer2, Ago2) and apoptosis (Caspase1, Caspase5) core genes in H. armigera larvae were decreased significantly after 24, 48 and 96 h feeding on a diet containing lethal and sublethal doses of fenoxycarb. Moreover, the mortality rate to HaNPV in the larvae treated with fenoxycarb increased compared to the control, leading to an increased replication of HaNPV. CONCLUSION: Together, our results suggest that the antiviral immune system could be modulated by JHA and facilitate HaNPV replication in the larvae, increasing the mortality rate of the insect larvae. Understanding the effect of JHA on antiviral immunity is an important step toward the process of exploiting JHAs and viral pathogens to control insect pests. © 2022 Society of Chemical Industry.
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MicroRNAs , Mariposas , Nucleopoliedrovírus , Fenilcarbamatos , Animais , RNA Helicases DEAD-box/metabolismo , Insetos/genética , Hormônios Juvenis/farmacologia , Larva , MicroRNAs/metabolismo , Fenilcarbamatos/farmacologia , Ribonuclease III/metabolismoRESUMO
The endocrine system modulates several physiological functions such as development and metamorphosis in insects. The normal growth and development of insects is interfered with insect growth regulators (IGRs), which act as mimics of insect hormones like juvenile hormone (JH) and ecdysone hormone. The effects of JH and its analogs on systemic immunity have been identified. However the effect of these compounds on local gut immunity is largely unknown. In this study, the effects of JH analog fenoxycarb on the local gut immunity of Helicoverpa armigera, gut bacteria population, and their role in the pathogenicity of Bacillus thuringiensis (Bt) were analyzed. The results showed that feeding fenoxycarb causes a decrease in the transcription level of IMD (Relish and PGPR-LC), ROS (DUOX and SOD) related genes and antimicrobial peptides (AMPs), followed by an overpopulation of gut bacteria. The fenoxycarb-treated larvae showed higher susceptibility to Bt compared to the control larvae. Overall, these findings collectively suggest that JH analog affects local gut immunity and gut bacteria titer.
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Bacillus thuringiensis , Disruptores Endócrinos , Mariposas , Animais , Disruptores Endócrinos/toxicidade , Mariposas/fisiologia , Larva , Bacillus thuringiensis/genética , Hormônios Juvenis/farmacologiaRESUMO
The highly pathogenic avian influenza (HPAI) H5N1 virus has received considerable attention during the past 2 decades due to its zoonotic and mutative features. This Virus is of special importance due to to the possibility of causing infection in human populations. According to it's geographical location, Iran hosts a large number of aquatic migratory birds every year, and since these birds can be considered as the host of the H5 HPAI, the country is significantly at risk of this virus. the In this study, the molecular characteristics of hemagglutinin (HA) and neuraminidase (NA) genes of the H5N8 strain were identified in Malard county of Tehran province and Meighan wetland of Arak city, Markazi province were investigated. Based on the analysis of the amino acid sequence of the HA genes, the cleavage site of the gene includes the PLREKRRKR/GLF polybasic amino acid motif, which is a characteristic of highly pathogenic influenza viruses. The HA gene of two viruses had T156A, S123P, S133A mutations associated with the increased mammalian sialic acid-binding, and the NA gene of two viruses had H253Y mutations associated with the resistance to antiviral drugs. Phylogenetic analysis of the HA genes indicated the classification of these viruses in the 2.3.4.4 b subclade. Although the A/Goose/Iran/180/2016 virus was also an H5N8 2.3.4.4 b virus, its cluster was separated from the A/Chicken/Iran/162/2016 virus. This means that the entry of these viruses in to the country happened through more than one window. Furthermore, it seems that the introduction of these H5N8 HPAI strains in Iran probably occurred through the West Asia-East African flyway by wild migratory aquatic birds.
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Virus da Influenza A Subtipo H5N1 , Vírus da Influenza A Subtipo H5N8 , Vírus da Influenza A , Influenza Aviária , Animais , Humanos , Vírus da Influenza A Subtipo H5N8/genética , Virus da Influenza A Subtipo H5N1/genética , Filogenia , Irã (Geográfico) , Animais Selvagens , Neuraminidase/genética , Hemaglutininas , Galinhas , MamíferosRESUMO
Several vaccine candidates for COVID-19 have been developed, and few vaccines received emergency approval with an acceptable level of efficacy and safety. We herein report the development of the first recombinant protein-based vaccine in Iran based on the recombinant SARS-CoV-2 spike protein in its monomeric (encompassing amino acid 1-674 for S1 and 685-1211 for S2 subunits) and trimer form (S-Trimer) formulated in the oil-in-water adjuvant system RAS-01 (Razi Adjuvant System-01). The safety and immunity of the candidate vaccine, referred to as RAZI-COV PARS, were evaluated in Syrian hamster, BALB/c mice, Pirbright guinea pig, and New Zeeland white (NZW) rabbit. All vaccinated animals received two intramuscular (IM) and one intranasal (IN) candidate vaccine at 3-week intervals (days 0, 21, and 51). The challenge study was performed intranasally with 5×106 pfu of SARS-CoV-2 35 days post-vaccination. None of the vaccinated mice, hamsters, guinea pigs, or rabbits showed any changes in general clinical observations; body weight and food intake, clinical indicators, hematology examination, blood chemistry, and pathological examination of vital organs. Safety of vaccine after the administration of single and repeated dose was also established. Three different doses of candidate vaccine stimulated remarkable titers of neutralizing antibodies, S1, Receptor-Binding Domain (RBD), and N-terminal domain (NTD) specific IgG antibodies as well as IgA antibodies compared to placebo and control groups (P<0.01). Middle and high doses of RAZI-COV PARS vaccine significantly induced a robust and quick immune response from the third-week post-immunization. Histopathological studies on vaccinated hamsters showed that the challenge with SARS-CoV-2 did not induce any modifications in the lungs. The protection of the hamster was documented by the absence of lung pathology, the decreased virus load in the lung, rapid clearance of the virus from the lung, and strong humoral and cellular immune response. These findings confirm the immunogenicity and efficacy of the RAZI-COV PARS vaccine. Of the three tested vaccine regimens, the middle dose of the vaccine showed the best protective immune parameters. This vaccine with heterologous prime-boost vaccination method can be a good candidate to control the viral infection and its spread by stimulating central and mucosal immunity.
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Vacinas contra COVID-19 , COVID-19 , Animais , Anticorpos Antivirais , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Cricetinae , Cobaias , Humanos , Camundongos , Modelos Animais , Coelhos , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Vacinas Combinadas , Vacinas SintéticasRESUMO
Foot and mouth disease (FMD) is a highly contagious transboundary disease of cloven-hoofed animals. In Iran, the disease is endemic with outbreaks occurring throughout the year. Mass vaccination of domestic ruminants has been adopted as a preventive strategy. A study was conducted to evaluate the effectiveness of currently in use FMD vaccines using official disease surveillance data. Surveillance data of FMD outbreaks and vaccination in cattle farms from January 2017 to March 2019 was obtained from the Iranian Veterinary Organization (IVO). A case-control study comprising 190 laboratory-confirmed cases and 380 randomly selected controls, frequency-matched by location and production type, was performed to estimate vaccine effectiveness (VE) of vaccines in industrial and semi-industrial farms. Multivariable logistic regression was used to estimate odds ratios based on brand of vaccine, time since vaccination, and within-farm vaccination coverage. A total of 2297 outbreaks occurred during the study period with majority (75%) reported from village epi-units. Only 38% of industrial and semi-industrial farms recorded vaccination during the studied period. Vaccination was effective against clinical disease with the highest VE observed in farms vaccinated with commercial vaccine brand A (VE = 0.90%, 95% CI 0.79-0.96), vaccinating > 94% of herd population (VE = 0.77%, 95%CI 0.54-0.98) and in < 35 days after vaccination (VE = 0.56%, 95% CI 0.04-0.8). The current high-potency vaccines confer medium protection in investigated cattle farms. The high occurrence of the disease in village epi-units and low coverage of vaccination in industrial and semi-industrial farms will contribute to maintenance and circulation of the virus in the susceptible population.
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Doenças dos Bovinos , Vírus da Febre Aftosa , Febre Aftosa , Vacinas Virais , Animais , Estudos de Casos e Controles , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/prevenção & controle , Surtos de Doenças/prevenção & controle , Surtos de Doenças/veterinária , Febre Aftosa/epidemiologia , Febre Aftosa/prevenção & controle , Irã (Geográfico)/epidemiologia , Vacinação/veterináriaRESUMO
BACKGROUND: MicroRNAs (miRNAs) are small regulatory non-coding RNAs that are involved in a variety of biological processes such as immunity, cell signaling and development by regulating gene expression. The whitefly Bemisia tabaci is a polyphagous vector that transmits many plant viruses causing economic damage to crops worldwide. In this study, we characterized and analyzed the expression of the miRNA core genes Argonaute-1 (Ago1) and Dicer-1 (Dcr1) in B. tabaci and explored the effect of their silencing on the insect's fitness. RESULTS: Our results showed that Ago1 and Dcr1 are differentially expressed in different tissues and developmental stages of B. tabaci. To determine the function of the miRNA pathway in B. tabaci, we silenced Ago1 and Dcr1 using specific double-stranded RNAs to the genes. RNA interference (RNAi) of Ago1 and Dcr1 decreased the expression level of the core genes and reduced the abundance of Let-7 and miR-184 miRNAs. Silencing of the miRNA pathway core gene also negatively affected the biology of B. tabaci by reducing fertility, fecundity and survival of this insect pest. CONCLUSIONS: Together, our results showed that silencing the miRNA pathway core genes reduced the miRNA levels followed by reduced fecundity and survival of B. tabaci, which highlighted the importance of the miRNA pathway in this insect. The miRNA core genes are attractive targets for developing an RNAi-based strategy for targeting this notorious insect pest. © 2022 Society of Chemical Industry.
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Hemípteros , MicroRNAs , Animais , Fertilidade/genética , Hemípteros/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Interferência de RNA , RNA de Cadeia DuplaRESUMO
Neoscytalidium novaehollandiae is one of the most important pathogens on woody plants which has increasingly been reported as a pathogen in different hosts in recent years. The pine trees are widely cultured in many cities of Iran. In recent years, dieback symptoms were observed on Pinus eldarica trees in Tehran and Qazvin provinces. The aim of this study was to investigate the dieback causal agent on P. eldarica trees in Iran. The branches and cones of P. eldarica trees were sampled for fungal isolation. The morphological and molecular characterizations (ITS, LSU, and TEF1-α regions) identified N. novaehollandiae as a dieback causal agent. This is the first report of N. novaehollandiae disease of P. eldarica trees in Iran. Furthermore, disease severity was assayed on 19 urban forest trees under three different temperature and relative humidity (RHs) regimes. C regime (29 °C and 15% RH) displayed more disease severity on detached branches than B (24 °C and 80% RH) and A (19 °C and 35% RH) ones. This study presents the host range of this pathogen, and showed that these potential hosts are prone to this pathogen under high temperature and low humidity which urban forest trees experienced in recent decades.
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Pinus , Árvores , Ascomicetos , Florestas , Irã (Geográfico)RESUMO
BACKGROUND: Avian influenza type A viruses (AIV) can infect a broad range of hosts including human and birds, making them an important viral pathogen with zoonotic potential. Ducks are a known reservoir for many avian viruses including the AIV. OBJECTIVES: To sequence the entire genome of duck-derived H3N2 and ran comprehensive phylogenetic analysis on them to study their origin. METHODS: In this study, 962 cloacal swabs were collected from domestic ducks at several live poultry markets (LPMs) of Gilan, Mazandaran and Golestan provinces of Iran in the year 2017. RESULTS: Preliminary assays such as haemagglutination inhibition assay (HI), Neuraminidase Inhibition assay(NI) and RT-qPCR suggested that 0.5% of the birds were infected by H3 low pathogenic influenza viruses (LPAI). Three isolates were selected for whole genome sequencing. The cleavage site of the HA genes showed a PEKQTR/GLF motif, an indicator of LPAI. Furthermore, BLAST and phylogenetic analyses of the HA gene showed high homology to the Eurasian lineage of H3N8 AIV (95.5%-97.1% to several European and East Asian isolates). However, the NA genes showed high homology (at most 96.5-96.9%) to those belonging to AIV N2 subtype. Furthermore, internal genes showed high homology (96%-98%) to a variety of duck-origin subtypes and glycoprotein combinations, which were different for each segment. This showed a complex reassortment between different subtypes. DISCUSSION: This report is the first whole genome sequencing and complete characterisation of H3N2 AIV from Iran. CONCLUSION: Such surveillance should continue to study the evolution and possible emergence of viruses with pandemic potential.
Assuntos
Vírus da Influenza A Subtipo H3N8 , Vírus da Influenza A , Influenza Aviária , Animais , Aves , Patos/genética , Humanos , Vírus da Influenza A Subtipo H3N2/genética , Influenza Aviária/epidemiologia , Irã (Geográfico)/epidemiologia , Filogenia , Aves Domésticas/genética , Sequenciamento Completo do Genoma/veterináriaRESUMO
In September 2017, an outbreak with high mortality, which showed the typical signs of ND, occurred among a flock of more than 2000 Eurasian collared doves in Konarak, southeast of Iran. A confirmed pigeon paramyxovirus type 1 strain was isolated from the brain tissues of the dead doves. The isolate, which was called Pigeon/Iran/Konarak/Barin/2017, was classified as a highly velogenic NDV. Complete genome sequencing and phylogenetic analysis showed that the isolate belonged to subgenotype XXI.2, which has never been reported from Iran before. The isolate had the highest homology (96.15%) with early 2010s Italian isolates. Further studies will be required to understand the diversity better.