Ahmad Fayaz
Pasteur Institute of Iran
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Featured researches published by Ahmad Fayaz.
Epidemiology and Infection | 2003
Susan A. Nadin-Davis; S. Simani; Janet Armstrong; Ahmad Fayaz; Alexander I. Wandeler
A molecular epidemiological study of 48 recent rabies isolates recovered from cases reported throughout Iran identified three distinct viral variants, the evolutionary origins of which were identified by phylogenetic comparison with rabies viruses originating from Europe and Asia. Members of group 1 (15 isolates) were recovered from the northern half of the country only, while those of group 2 (31 isolates) were widely dispersed; both groups clustered within the widely disseminated cosmopolitan lineage. The two isolates of group 3 were detected in the northeastern tip of the country only and belonged to the Arctic strain. Rapid variant discrimination tools, employing restriction fragment length polymorphisms applied to amplified fragments of the viral genome, were devised whilst antigenic characterization of representative viruses identified a small panel of monoclonal antibodies that were also discriminatory. The future application of such methods should provide valuable epidemiological information on rabies incidence in Iran.
Proteomics | 2009
Fatemeh Zandi; Naser Eslami; Masoomeh Soheili; Ahmad Fayaz; Alireza Gholami; Behrouz Vaziri
Rabies is a neurotropic virus that causes a life threatening acute viral encephalitis. The complex relationship of rabies virus (RV) with the host leads to its replication and spreading toward the neural network, where viral pathogenic effects appeared as neuronal dysfunction. In order to better understand the molecular basis of this relationship, a proteomics study on baby hamster kidney cells infected with challenge virus standard strain of RV was performed. This cell line is an in vitro model for rabies infection and is commonly used for viral seed preparation. The direct effect of the virus on cellular protein machinery was investigated by 2‐DE proteome mapping of infected versus control cells followed by LC‐MS/MS identification. This analysis revealed significant changes in expression of 14 proteins, seven of these proteins were viral and the remaining were host proteins with different known functions: cytoskeletal (capping protein, vimentin), anti‐oxidative stress (superoxide dismutase), regulatory (Stathmin), and protein synthesis (P0). Despite of limited changes appeared upon rabies infection, they present a set of interesting biochemical pathways for further investigation on viral‐host interaction.
Epidemiology and Infection | 2007
F. Farahtaj; Christopher Gallimore; Miren Iturriza-Gomara; Mahnaz Taremi; M. R. Zali; H. Edalatkhah; Ahmad Fayaz; Jim Gray
Rotaviruses were detected by enzyme-linked immunosorbent assay (ELISA) in 92 out of 374 faecal samples collected between November 2003 and October 2004 at the Markaz Tebbi Koudakan Hospital, Tehran, Iran, from children aged 6 months to 5 years. Analysis of clinical and disease severity data showed a significant association between rotavirus infection and diarrhoea, vomiting and severe dehydration. Ninety-two samples (64 rotavirus ELISA-positive and 28 ELISA-negative samples) were sent to the Enteric Virus Unit, Virus Reference Department, Centre for Infection, Health Protection Agency, UK for rotavirus characterization by G-typing, P-typing and subgrouping (SG) using reverse transcriptase (RT)-PCR, semi-nested PCR and sequencing methods. In this study, both common and uncommon rotavirus genotypes were detected. The most prevalent types were G1P[8], SGII (59.2%) followed by G9P[8] SGII (15.5%) which has not been previously reported from Iran. Unusual genotypes G1P[10] SGI (2.8%) and G12P[8] SGII (1.4%) and strains derived from reassortment between common co-circulating genotypes such as G1P[4] SGII represented 5.6% of strains. Mixed infections with combinations of G1+G4P[8] SGII and G1+G9P[8] SGII were also found. This contrasts with previous reports from Iran in which a small number of common rotavirus strains (G1 and G4) were found. This study highlights the need for continued surveillance and characterization of rotaviruses to take account of the rapid evolution and introduction of novel rotaviruses into the human population.
Journal of Medical Virology | 2013
Fatemeh Zandi; Naser Eslami; Fatemeh Torkashvand; Ahmad Fayaz; Vahid Khalaj; Behrouz Vaziri
Rabies virus invades the nervous system, induces neuronal dysfunction and causes death of the host. The disruption of the cytoskeletal integrity and synaptic structures of the neurons by rabies virus has been postulated as a possible basis for neuronal dysfunction. In the present study, a two‐dimensional electrophoresis/mass spectrometry proteomics analysis of neuroblastoma cells revealed a significant effect of a virulent strain of rabies virus on the host cytoskeleton related proteins which was quite different from that of an attenuated strain. Vimentin, actin cytoplasmic 1 isoform, profilin I, and Rho‐GDP dissociation inhibitor were host cell cytoskeletal related proteins changed by the virulent strain. The proteomics data indicated that the virulent strain of rabies virus induces significant expression changes in the vimentin and actin cytoskeleton networks of neurons which could be a strong clue for the relation of cytoskeletal integrity distraction and rabies virus pathogenesis. In addition, the expression alteration of other host proteins, particularly some structural and regulatory proteins may have potential roles in rabies virus pathogenesis. J. Med. Virol. 85:336–347, 2013.
Molecular Biology Reports | 2013
Firouzeh Farahtaj; Fatemeh Zandi; Vahid Khalaj; Peyvand Biglari; Ahmad Fayaz; Behrouz Vaziri
In order to extend the knowledge of rabies pathogenesis, a two-dimensional electrophoresis/mass spectrometry based postmortem comparative proteomics analysis was carried out on human brain samples. Alteration in expression profile of several proteins was detected. Proteins related to cytoskeleton, metabolism, proteasome and immune regulatory systems showed the most changes in expression levels. Among these groups, the cytoskeleton related proteins (dynein light chain, β-centractin, tubulin alpha-1C chain and destrin) and metabolism associated proteins (fatty acid-binding protein, macrophage migration inhibitory factor, glutamine synthetase and alpha enolase) were the main altered proteins. These alterations may be considered as an evidence of disturbances in neuronal key processes including axonal transport, synaptic activity, signaling and metabolic pathways in rabies virus infected human brain.
Vaccine | 2011
Ahmad Fayaz; S. Simani; Alireza Janani; Firouzeh Farahtaj; Peyvand Biglari; Nader Howeizi; Nasser Eslami
In 1975-1976 forty-five persons severely bitten by rabid wolves and dogs in Iran were treated successfully against rabies with HDCV. In this study contact was made with 26 of 45 above persons, 32 years after their initial treatment and all had rabies neutralizing antibody ranging from 0.3 to 2.69 IU/ml of serum. Of the 26 persons, 17 had received a booster dose of HDCV, 28 years ago and the remaining 9 persons, who had not received any booster since the initial treatment, were given one booster dose of HDCV. All 9 of these patients developed an anamnestic response after their booster inoculation. This study confirms the persistence of rabies neutralizing antibody in persons that received post-exposure vaccination with HDCV, 32 years previously. Furthermore, a single booster inoculation with HDCV resulted in anamnestic response in all individuals.
Tropical Doctor | 2014
Firouzeh Farahtaj; Ahmad Fayaz; Nader Howaizi; Peyvand Biglari; Alirez Gholami
Background Like most Asian and African countries, Iran is highly endemic for rabies, which is a preventable disease with the timely utilisation of post-exposure prophylaxis (PEP). With the availability of affordable vaccination in Iran, there are still several rabies deaths which are assumed misdiagnosed or received ineffective PEP. Methods We reviewed the files of 16 human rabies deaths, consisting of two groups: 1, ineffective treatment; and 2, erroneous PEP. Results Most of the studied cases were male and were from rural areas. Stray dogs were found to be the common biting animal (68.75%). Of the patients, 10/16 (62.5%) who had injuries on their head and/or face demonstrated shorter incubation periods. The incubation period was longer in a 4-year-old boy who sustained injuries in his abdomen and back. All the patients in group 1 received four doses of vaccine and administration of human rabies immune globulin (HRIG), and death occurred with the mean of 49 days after the bite. This mean was 27 days in three patients in group 2, who received vaccine without administration of HRIG. Conclusion In a total of 1,188,579 cases of PEP given in Iran during: 2002–2011, it is not known whether all PEPs were correctly administered by World Health Organization standards. Extending rabies awareness programmes and timely PEP education in the community in accordance with the implementation of rabies control measures might lead to a decrease in these unfortunate scenarios and heavy financial burden of vaccination required due to the prevalence of rabies.
Indian Journal of Virology | 2012
Behrouz Vaziri; Fatemeh Torkashvand; Naser Eslami; Ahmad Fayaz
The CNS immune response to rabies virus has been shown to be influenced by virulence of the virus strains. There is no comprehensive report of the peripheral immune response against different strains of rabies virus. In this report we used a comparative proteome analysis to find the early events in the spleen lymphocytes of mice infected by a street strain and an attenuated strain of the rabies virus. Differentially expressed proteins were identified which play important biological roles such as T and B lymphocyte activation (coronin 1), antiviral activity (peroxiredoxin 1), and cytoskeletal reorganization (cofilin 1). These results could be strong hints of early divergence on peripheral immune response under influence of viral strain and their pathogenicity.
Archives of Iranian Medicine | 2008
Ali Eslamifar; Amitis Ramezani; Mehdi Razzaghi-Abyaneh; Parisa Mashayekhi; Mahboob Hazrati; Tina Askari; Ahmad Fayaz; Arezoo Aghakhani
Developments in biologicals | 2008
A R Janani; Ahmad Fayaz; S. Simani; Firouzeh Farahtaj; N. Eslami; Nader Howaizi; Peyvand Biglari; M. Sabetghadam