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1.
BMC Infect Dis ; 24(1): 429, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649818

RESUMO

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a highly contagious virus that uses angiotensin converting enzyme 2 (ACE2), a pivotal member of the renin-angiotensin system (RAS), as its cell-entry receptor. Another member of the RAS, angiotensin II (Ang II), is the major biologically active component in this system. There is growing evidence suggesting that serum miRNAs could serve as prognostic biomarkers for SARS-CoV-2 infection and regulate ACE2 expression. Therefore, the aim of this study is to evaluate the changes in the serum levels of sACE2 and Ang II, as well as the expression level of miR-141-3p and miR-421 in SARS-CoV-2 positive and negative subjects. METHODS: In the present study, the serum levels of sACE2 and Ang II were measured in 94 SARS-CoV-2 positive patients and 94 SARS-CoV-2 negative subjects with some symptoms similar to those of SARS-CoV-2 positive patients using the ELISA method. In addition, the expression level of miR-141-3p and miR-421 as ACE2 regulators and biomarkers was evaluated using quantitative real-time PCR (qRT-PCR) method. RESULTS: The mean serum sACE2 concentration in the SARS-CoV-2-positive group was 3.268 ± 0.410 ng/ml, whereas in the SARS-CoV-2 negative group, it was 3.564 ± 0.437 ng/ml. Additionally, the mean serum Ang II level in the SARS-CoV-2 positive and negative groups were 60.67 ± 6.192 ng/L and 67.97 ± 6.837 ng/L, respectively. However, there was no significant difference in the serum levels of sACE2 (P value: 0.516) and Ang II (P value: 0.134) between the SARS-CoV-2 positive and negative groups. Meanwhile, our findings indicated that the expression levels of miR-141-3p and miR-421 in SARS-CoV-2 positive group were significantly lower and higher than SARS-CoV-2 negative group, respectively (P value < 0.001). CONCLUSIONS: Taken together, the results of this study showed that the serum levels of sACE2 and Ang II in SARS-CoV-2 positive and negative subjects were not significantly different, but the expression levels of miR-141-3p and miR-421 were altered in SARS-CoV-2 positive patients which need more investigation to be used as biomarkers for COVID-19 diagnosis.


Assuntos
Angiotensina II , Enzima de Conversão de Angiotensina 2 , COVID-19 , MicroRNAs , SARS-CoV-2 , Humanos , MicroRNAs/sangue , COVID-19/diagnóstico , COVID-19/sangue , COVID-19/virologia , Enzima de Conversão de Angiotensina 2/sangue , Enzima de Conversão de Angiotensina 2/genética , Angiotensina II/sangue , Masculino , Feminino , Estudos de Casos e Controles , Pessoa de Meia-Idade , Adulto , Biomarcadores/sangue , Idoso
2.
BMC Pediatr ; 24(1): 31, 2024 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-38200453

RESUMO

BACKGROUND: Following rubella virus control, the most important cause of congenital infections is human cytomegalovirus (HCMV). Congenital CMV (cCMV) may happen both in primary and non-primary maternal infections. The present study aimed to screen cCMV in symptomatic newborns suspected of congenital rubella syndrome (CRS) in Iran. METHODS: Out of 1629 collected infants' serum samples suspected of CRS but negative for rubella IgM, 524 samples were selected regarding cCMV complications. These samples were divided into two age groups: 1- one month and younger, 2- older than 1 month up to one year. Anti-HCMV IgM detection was performed on these serums. Then HCMV IgG avidity assay and HCMV DNA detection were carried out on all samples with positive and borderline results in IgM detection. RESULTS: Herein, 3.67% of symptomatic infants aged one month and younger had positive and borderline HCMV IgM, 12.5% of which had a low avidity index (AI). HCMV IgM detection rate among symptomatic infants older than one month to one year was 14.5%. Identified genotypes in this study were gB-1(63.63%), gB2 (18.18%), and gB3 (18.18%), respectively. CONCLUSIONS: This comprehensive study was performed on serum samples of symptomatic infants clinically suspected of cCMV from all over Iran. There was a good correlation between serology findings and PCR.


Assuntos
Infecções por Citomegalovirus , Síndrome da Rubéola Congênita , Recém-Nascido , Lactente , Humanos , Síndrome da Rubéola Congênita/diagnóstico , Estudos Transversais , Irã (Geográfico)/epidemiologia , Infecções por Citomegalovirus/diagnóstico , Anticorpos Antivirais , Imunoglobulina M
3.
Trop Dis Travel Med Vaccines ; 9(1): 23, 2023 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-38143281

RESUMO

Poxviruses are large and diversified viruses that cause an emerging zoonotic disease known as monkeypox (mpox). In the past, mpox predominated primarily in the rural rainforests of Central and West Africa. Recently, the exportation of mpoxv from Africa to other continents has been progressively reported. However, the lack of travel history to Africa in most of the currently reported cases in 2022 promotes the sign of changing epidemiology of this disease. Concerns over the geographic distribution and continued resurgence of mpox is growing. In this review, we addressed the geographic distribution, transmission, reasons for the resurgence of mpox, and vaccination. Although the precise cause of the resurgence in mpox cases is mostly unknown, several suggested factors are believed to be waning immunity, accumulation of unvaccinated people, ecological conditions, risk behaviors of men who have sex with men, and genetic evolution.

4.
Clin Case Rep ; 11(10): e8030, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37850062

RESUMO

In SARS-CoV-2 pandemic different disorders in coagulation pathways in COVID-19 patients were reported. We described a 44-year-old female with COVID-19 and protein C deficiency history. She did not show any coagulation disorder during her disease course. Complete genome sequencing of SARS-CoV-2 was performed and some mutations identified and compared with Wuhan strain. Besides hospitalized patients, in COVID-19 outpatients with low concentration of protein C, early prescription of an anticoagulant such as heparin could be helpful in prevention of venous thromboembolism or pulmonary embolism.

5.
BMC Infect Dis ; 23(1): 591, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37697227

RESUMO

BACKGROUND: Human orthopneumovirus (HOPV) or respiratory syncytial virus (RSV) is one of the important causes of acute respiratory infections (ARIs) during the cold months of the year worldwide. Many countries have reported an absence of ARIs due to HOPV during the winter of 2020-2021 associated with preventive measures to reduce the spread of SARS-CoV2. However, with the reduction of COVID-19 public health restrictions and the absence of immunity in the community due to the lack of exposure in the previous season, many countries had a delayed HOPV outbreak. Here we reported the impact of COVID-19 on the changing pattern of HOPV infection in Iran. METHODS: Throat and nasopharyngeal swab samples were collected from patients (children and adults) with ARIs and sent to the Iran National Influenza Center. After RNA extraction, Real time RT-PCR was performed for HOPV detection. RESULTS: In 260 samples collected from patients with ARIs in three different groups, which included children in March 2021, pilgrims in July 2022, and outpatients during November and December 2022, no HOPV was detected in any group. CONCLUSIONS: The lack of HOPV activity in Iran during the winter of 2020-2021 and then the resurgence in spring 2022 and again the absence of activity in summer and autumn 2022 was extraordinary in the HOPV epidemiology, and probably due to the implementation of public health non-pharmaceutical interventions to reduce the spread of SARS-CoV2. Although it is not possible to keep such restrictions, similar methods can be taken to control outbreaks caused by respiratory viruses.


Assuntos
COVID-19 , Vírus Sincicial Respiratório Humano , Infecções Respiratórias , Adulto , Criança , Humanos , Irã (Geográfico)/epidemiologia , RNA Viral , COVID-19/epidemiologia , SARS-CoV-2 , Vírus Sincicial Respiratório Humano/genética
6.
Health Sci Rep ; 6(9): e1538, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37662536

RESUMO

Background and Aims: Real-time reverse-transcriptase polymerase chain reaction (real-time RT-PCR) is the gold standard test for diagnosis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, when the test result is near the detection limit of the assay the possibility of getting false positive or negative results is high. In addition, it might result in single target gene positive (STGP) results which should be interpreted with caution. Methods: This study was performed on 29,962 nasal swabs from July 1 to August 31, 2020. Ct values less than 40 for each or both of N and RdRp genes were recommended to be selected as positive. Positive samples for one gene with the Cts more than 35 were rechecked by adding more templates. Results: The results showed that 1016 (3.39%) samples were positive just for one gene with high Ct values. The results of the second reactions showed that 325 (31.99%) samples were positive for both N and RdRp which were reported positive, 301 (29.65%) were positive only for one gene which were considered as suspicious cases and resampling was suggested for them. Finally, 390 (38.385%) samples were negative for both genes. Conclusion: In conclusion, tracking weak positive results of SARS-CoV-2 real-time RT-PCR revealed that most of the individuals who were STGP clean the infection completely in less than a week which showed they were in the convalescent phase of infection. However, some of them who were in the beginning of infection showed a decrease in Ct value during a week, so they could spread the virus in the society.

7.
Influenza Other Respir Viruses ; 17(8): e13184, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37565071

RESUMO

Introduction: This study is the first study in which demographic, laboratory data, and outcomes of coronavirus disease-2019 (COVID-19) patients due to the circulating SARS-CoV-2 infections caused by different variants (Alpha, Delta, and Omicron) are compared in Iran. Methods: We conducted a retrospective study of confirmed hospitalized COVID-19 cases from April 9, 2021, to May 22, 2022. Demographic data and laboratory findings were extracted from patients' electronic medical records on the first day of admission to the hospital. All patients were followed up for outcomes related to COVID-19 including intensive care unit (ICU) admission and mortality rate. Results: Of 760 confirmed hospitalized COVID-19 cases, 362, 298, and 100 represented patients during waves 4-6, respectively. During the Omicron wave, hospitalized patients were older than the other two waves and had a lower median level of C-reactive protein (CRP), alanine transaminase (ALT), aspartate transaminase (AST), and erythrocyte sedimentation rate (ESR). The median length of hospital stay during waves 4-6 was 5 days (interquartile range [IQR]: 4.0-8.0), 7 days (IQR: 6.0-11), and 6 days (IQR: 5.0-9.0), respectively (p < 0.001). The rate of ICU admission during waves 4-6 significantly increased. Conclusions: Although the Omicron variant caused less severe disease, in older patients who were hospitalized due to Omicron infection, longer hospital and ICU stays were reported, which could be attributed to their old age. In particular, elderly patients are more vulnerable to severe COVID-19; otherwise, as expected, other laboratory parameters and clinical outcomes were in accordance with differences in pathogenicity and infectivity of these variants.

8.
Iran J Microbiol ; 15(1): 155-162, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37069918

RESUMO

Background and Objectives: Human rhinoviruses (HRVs) and human adenoviruses (HAdVs) are among the most prevalent viruses in hospitalized patients with severe acute respiratory infection (SARI). This study aimed to evaluate the molecular characterization of HRV and HAdV in hospitalized patients with SARI, who aged ≤ 18 years in Tehran, Iran. Materials and Methods: To detect these two viruses, a conventional nested RT-PCR (Reverse transcription-polymerase chain reaction) assay was performed on 264 throat swabs collected from December 2018 to March 2019. The epidemiological data were analyzed and phylogenetic trees were constructed. Results: Of 264 cases with SARI, 36 (13.6%) and 28 (10.6%) were positive for HAdV and HRV respectively. Of 21 HRV sequenced samples, HRV-A (42.9%), HRV-B (9.5%) and HRV-C (47.6%) and of 36 HAdV sequenced samples, HAdV-C6 (38.9%), HAdV-B7 (22.2%), HAdV-B3 (11.1%), HAdV-B16 (5.6%), HAdV-C5 (13.9%), HAdV-C57 (5.6%), HAdV-E4 (2.8%); were detected in children with SARI. Some viral genotypes appeared to cause more severe disease, which may lead to hospitalization. Conclusion: Large-scale studies are recommended to investigate the epidemiology and molecular characterizations through surveillance networks to provide useful information on etiology, seasonality, and demographic associations in patients with SARI.

9.
Eur J Med Res ; 28(1): 94, 2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36823532

RESUMO

SARS-COV-2 is responsible for the current worldwide pandemic, which started on December 2019 in Wuhan, China. On March 2020 World Health Organization announced COVID-19 as the new pandemic. Some SARS-COV-2 variants have increased transmissibility, cause more severe disease (e.g., increased hospitalizations or deaths), are resistant to antibodies produced by the previous infection or vaccination, and there is more difficulty in treatment and diagnosis of them. World Health Organization considered them as SARS-CoV-2 variants of concern. The introductory reproduction rate (R0) is an epidemiologic index of the transmissibility of the virus, defined as the average number of persons infected by the virus after known contact with an infectious person in a susceptible population. An R0 > 1 means that the virus is spreading exponentially, and R0 < 1, means that the outbreak is subsiding. In various studies, the estimated R and VOC growth rates were reported to be greater than the ancestral strains. However, it was also a low level of concordance between the estimated Rt of the same variant in different studies. It is because the R of a variant not only dependent on the biological and intrinsic factors of the virus but also several parameters can affect the R0, including the duration of contagiousness and the likelihood of infection per contact. Evaluation of changes in SARS-CoV-2 has shown that the rate of human-to-human transmission of this virus has increased. Like other viruses with non-human sources which succeeded in surviving in the human population, SARS-CoV-2 has gradually adapted to the human population, and its ability to transmit from human to human has increased. Of course, due to the continuous changes in this virus, it is crucial to survey the rate of transmission of the virus over time.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/epidemiologia , Pandemias , Reprodução
10.
Iran J Public Health ; 52(12): 2621-2629, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38435775

RESUMO

Background: Whole viral genome sequencing with next generation sequencing (NGS) technique is useful tool for determining the diversity of variants and mutations of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In this study we have attempted to characterize the mutations and circulating variants of the SARSCoV-2 genome during the 4th wave of COVID-19 pandemic in Tehran, Iran in 2021. Methods: We performed complete genome sequencing of 15 SARS-CoV-2 detected from 15 COVID-19 patients during the 4th wave of COVID-19 pandemic with NGS. Three groups of the patients at the beginning, middle and the end of the 4th wave were compared together. Results: We detected alpha and delta variants during the 4th wave of the pandemic. The results illustrated a dominance of amino acid substitution D614G in spike, and the most frequent mutants were N-R203K, G204R, S235F, nsp12-P323L, nsp6-G106del, G107del and F108del. Conclusion: The detection of the virus mutations is a useful procedure for identifying the virus behavior and its genetic evolution in order to improve the efficacy of the monitoring strategies and therapeutic measures.

11.
BMC Pediatr ; 22(1): 583, 2022 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-36207696

RESUMO

BACKGROUND: Human adenovirus (HAdV) is an important viral agent in children which can lead to severe acute respiratory infection (SARI). Reports on molecular epidemiology of HAdVs in Iran are limited. This case-control study is conducted to compare the HAdV infection rate and molecular epidemiology among two groups of children with and without respiratory symptoms in Tehran, Iran during 2018-2019. METHODS: Nested PCR was performed on 120 oropharyngeal swabs taken from children aged five and younger with SARI who were hospitalized as the case group, and 120 oropharyngeal swabs were collected from children of the same age without respiratory symptoms as the control group. For positive samples Sanger sequencing was done and a phylogenetic tree was drawn afterward. RESULTS: Out of 120 cases, 8 (6.6%) tested positive for eachHAdV types including 6 (75%) HAdV-B7, 1 (12.5%) HAdV-C2, and 1 (12.5%) HAdV-C6. Among the control group, out of 120 samples, 8 (6.6%) were positive comprising 5 (62.5%) HAdV-C5, 2 (25%) HAdV-F41, and 1 (12.5%) HAdV-C6. CONCLUSION: The present study indicated a different viewpoint of HAdV molecular epidemiology in which the genotypes were compared in children with and without respiratory symptoms. HAdV prevalence was equally common in cases and controls but different genotypes were detected in these two groups. HAdV-B7 was the main type among children with SARI, dissimilar to children with no respiratory symptoms where HAdV-C5 was the predominant type. Detecting HAdV-F in oropharyngeal swabs was a rare finding, which requires further investigation.


Assuntos
Infecções por Adenovirus Humanos , Adenovírus Humanos , Infecções Respiratórias , Infecções por Adenovirus Humanos/diagnóstico , Infecções por Adenovirus Humanos/epidemiologia , Adenovírus Humanos/genética , Estudos de Casos e Controles , Criança , Genótipo , Humanos , Lactente , Irã (Geográfico)/epidemiologia , Epidemiologia Molecular , Filogenia , Infecções Respiratórias/epidemiologia , Análise de Sequência de DNA
12.
Intervirology ; 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35858540

RESUMO

INTRODUCTION: Human Cytomegalovirus (HCMV) infection is one of the most common viral complications in kidney transplant recipients. Although there are effective treatments strategies for the HCMV infection, this infection is still one of the causes of kidney transplant rejection. METHODS: A total of 246 kidney transplant recipients participated in this cross-sectional study. Viral DNA was extracted from these plasma samples and the presence of HCMV genome was determined by Semi-nested PCR with specific primers for HCMV B glycoprotein gene. Sanger sequencing analyses were carried out to determine HCMV genotypes and Mega x software was used for nucleotide alignment and construction of a phylogenetic tree. RESULTS: Human cytomegalovirus DNA was detected in 11 (4.47%) recipients. According to the phylogenetic analysis, HCMV gB3 was 50% among kidney transplant recipients, followed by gB4 30% and gB1 20% however, the gB2 genotype was not detected. CONCLUSIONS: This study demonstrated that the HCMV infection in our patients is relatively low because all transplant recipients received appropriate prophylaxis, thereby antiviral prophylaxis is recommended for all patients at risk of HCMV infection after kidney transplantation. Also, gB3 was the most predominant genotype among our kidney transplant recipients that was related to the higher rate of prevalence of severe HCMV infections. Moreover, elevated serum creatinine level was detected in patients at the time of detection of HCMV infection.

13.
PLoS One ; 17(5): e0267847, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35499994

RESUMO

PURPOSE: Whole genome sequencing of SARS-CoV2 is important to find useful information about the viral lineages, variants of interests and variants of concern. As there are not enough data about the circulating SARS-CoV2 variants in Iran, we sequenced 54 SARS-CoV2 genomes during the 5 waves of pandemic in Iran. METHODS: After viral RNA extraction from clinical samples collected during the COVID-19 pandemic, next generation sequencing was performed using the Nextseq platform. The sequencing data were analyzed and compared with reference sequences. RESULTS: During the 1st wave, V and L clades were detected. The second wave was recognized by G, GH and GR clades. Circulating clades during the 3rd wave were GH and GR. In the fourth wave GRY (alpha variant), GK (delta variant) and one GH clade (beta variant) were detected. All viruses in the fifth wave were in clade GK (delta variant). There were different mutations in all parts of the genomes but Spike-D614G, NSP12-P323L, N-R203K and N-G204R were the most frequent mutants in these studied viruses. CONCLUSIONS: These findings display the significance of SARS-CoV2 monitoring to help on time detection of possible variants for pandemic control and vaccination plans.


Assuntos
COVID-19 , Influenza Humana , COVID-19/epidemiologia , Humanos , Influenza Humana/epidemiologia , Irã (Geográfico)/epidemiologia , Pandemias , RNA Viral/genética , SARS-CoV-2/genética , Sequenciamento Completo do Genoma
14.
Future Virol ; 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35586148

RESUMO

Objective: To evaluate SARS-CoV-2 genome detection using pooled samples by RT-qPCR assay, compared to individual samples. Method: At first all samples were tested individually using two commercial methods targeting ORF1ab, NP and E genes. Then, four experimental groups of samples were pooled and evaluated using the same detection methods. Findings: Compared to the individual sample testing, the sample pooling conserved the sensitivity of the detection in all groups of pooled samples when the Ct value in single test was lower than 33. Conclusion: Specimen pooling may fail to detect positive samples with high Ct values. However, in scarcity of reagents or in population surveys, it could be considered as an alternative method in low prevalence settings.

15.
Infect Disord Drug Targets ; 22(6): e230222201383, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35209824

RESUMO

BACKGROUND: In late December 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV2), the causative agent of coronavirus disease 2019 (COVID-19), spread to almost all countries worldwide. The outbreak of this virus has been confirmed on 19th February, 2020, in Iran. OBJECTIVE: The aim of this study was to investigate the time of viral RNA clearance in swab and serum samples of COVID-19 patients having received different medications. We also evaluated different factors that may affect viral RNA persistence in patients infected by SARS-CoV-2. METHODS: In March 2020, twenty-one hospitalized COVID-19 patients participated in this prospective study. All patients received antiviral agents in their routine care. Throat swabs and blood samples were obtained from all patients in different intervals, including day 3 or 5, day 7, day 10, and finally, 14 days after the first positive real-time RT-PCR (rRT-PCT) test. RESULTS: The median time from the symptom onset (SO) to the first negative rRT-PCR results for throat swabs and serum samples of COVID-19 patients was 18 and 14 days, respectively. These times were more significant in patients with lymphopenia, oxygen saturation ≤ 90%, and comorbidity. CONCLUSION: This preliminary study highlights that SASR-CoV-2 RNA was not detectable in the upper respiratory tract for longer than three weeks. In addition, SARS-CoV-2 may persist for a long period of time in the respiratory than in the serum samples. This study supports the idea that in limited resource settings, the patients should be tested earlier than three weeks for discharge management.


Assuntos
COVID-19 , Humanos , Estudos Prospectivos , RNA Viral , SARS-CoV-2 , Testes Sorológicos
16.
Congenit Anom (Kyoto) ; 62(2): 54-67, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34961973

RESUMO

Intrauterine viruses can infect the decidua and placenta and cause adverse effects on the fetus during gestation. This review discusses the contribution of various viral infections to miscarriage and the molecular mechanisms by which viruses can cause devastating effects on healthy fetuses and induce miscarriage. Severe acute respiratory syndrome coronavirus 2 as newly emerged coronavirus was considered here, due to the concerns about its role during pregnancy and inducing miscarriage, as well. In this narrative review, an extensive literature search was conducted to find all studies investigating viral infections in miscarriage and their molecular mechanisms published over the past 20 years. The results of various studies investigating the roles of 20 viral infections in miscarriage are presented. Then, the mechanisms of pregnancy loss in viral infections were addressed, including alteration of trophoblast invasion and placental dysfunction, inducing excessive maternal immune response, and inducing apoptosis in the placental tissue. Viruses may cause pregnancy loss through different mechanisms and our knowledge about these mechanisms can be helpful for controlling or preventing viral infections and achieving a successful pregnancy.


Assuntos
Aborto Espontâneo , COVID-19 , Complicações Infecciosas na Gravidez , Viroses , Feminino , Humanos , Transmissão Vertical de Doenças Infecciosas , Placenta , Gravidez , SARS-CoV-2 , Viroses/complicações
17.
Tanaffos ; 21(4): 448-454, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37583781

RESUMO

Background: Hajj is one of the main challenges of public health and infection control. Hajj-associated respiratory tract infections are very common during the pilgrimage. Studies have shown that human rhinovirus (HRV) is one of the most common causes of respiratory illnesses among pilgrims. The aim of this study was to investigate the prevalence and genotypes of HRV among Iranian pilgrims with severe acute respiratory infection (SARI) during the 2017 Hajj season. Materials and Methods: Throat swabs or washes were collected from 104 pilgrims with SARI and transported to the National Influenza Center, School of Public Health, Tehran University of Medical Sciences. Specimens were screened for HRV by Nested PCR with primers for 5'UTR, and virus genotypes were determined using PCR with VP4-VP2 primers and sequencing method. Results: Twenty-one cases were positive for HRV (20.19 %). The HRV species and types of 8 positive samples were: HRV-A21 (1/8, 12.5%), followed by HRV-B91 (3/8, 37.5%) and HRV-C (4/8, 50%) un-typed. Conclusion: This study showed that HRV has a high prevalence in Iranian Hajj pilgrims. As there is no vaccine or antiviral therapy for HRV, prevention methods are the best way for infection control.

18.
Biotechnol Appl Biochem ; 69(1): 124-128, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33347649

RESUMO

Coronaviruses recognize a variety of host receptors to infect many humans and animals. Newly emerged severe acute respiratory syndrome coronavirus2 (SARS-CoV-2) recognizes angiotensin-converting enzyme 2 (ACE2) to gain entry into different cells. Interestingly, besides SARS-CoV2, four other human coronaviruses (HCoVs) use three different ectopeptidases (ACE2, dipeptidyl peptidase 4, and aminopeptidase N) as receptors independent of their common peptidase activity. This issue has led to the important question "why do several HCoVs rely on peptidases as their receptors?." In this paper, we discussed to answer this question. Mostly, it seems that the use of peptidases by HCoVs may be more related to their widespread presence on target cells and also viruses prefer to take advantage of molecules with relatively low affinity for their natural ligands through evolving a stronger binding affinity to the surface receptors for entry and endocytosis. Meanwhile evolutionary conservation of these receptors may allow HCoVs to switch between different host species. Finally, the choice of peptidases by HCoVs may reflect the "trial and error" nature of evolution. In conclusion, substantial efforts are needed to get a strong picture of this fascinating question and poorly explored area. Detailed understanding of the entry mechanisms offers opportunities for the development of refined strategies to stop viruses.


Assuntos
SARS-CoV-2 , COVID-19 , Especificidade de Hospedeiro , Humanos , Peptídeo Hidrolases
19.
Iran J Microbiol ; 14(4): 545-553, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36721506

RESUMO

Background and Objectives: Neuraminidase inhibitors (NAIs) as an imperative antiviral for influenza prophylaxis and treatment are being consumed worldwide. Increasing use of these antivirals might be associated with drug resistance. Regarding the significance of these variations, this study aimed to investigate the mutations occurring in the NA gene of influenza A viruses leading to oseltamivir resistance during 2017-2019 in Iran. Materials and Methods: In this cross-sectional study, 40 influenza A (H1N1, H3N2) strains, isolated in National Influenza Center (NIC) from patients with Severe Acute Respiratory Infection (SARI) during 2017-2019 were subjected to RT-PCR and sequencing of NA complete gene. The frequency of oseltamivir resistance and variation of NA amino acids in these strains were investigated. Results: No significant mutation conferring oseltamivir resistance was detected. However, NA antigenic sites in these strains depicted minor changes compared to the vaccine strains. Among H3N2 isolates, mutations at 329, 344, 346 and 385 and among H1N1 isolates mutations at 143 and 188 residues occurred in NA antigenic regions. Conclusion: Evaluation of NA gene sequences, showed no resistant viruses to oseltamivir. Given that the viruses in the present study were the last viruses circulating in Iran before COVID-19 pandemic, the results will be beneficial to have a worthy comparison with the strains circulating after the pandemic. Constant monitoring for the emergence of drug-resistant variants and antigenic changes are crucial for all countries.

20.
Clin Case Rep ; 9(10): e05009, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34745621

RESUMO

Patients with underlying health conditions are vulnerable to invasive fungal infection following COVID-19. It seems that uncontrolled diabetes mellitus makes patients susceptible to both severe COVID-19 and mucormycosis.

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