20 research outputs found
A Review on Relationship Between Human Endogenous Retrovirus Groups and Human Diseases
Various factors are involved in the incidence of some diseases like autoimmune, psychiatric and cancerous ones. One of these probable factors is considered as the endogenous retroviruses, for example, proviruses that have been introduced in previous generations in some organisms' genome, and make up over 8% of the human genome. Recent studies have indicated that these factors and their related products (including RNA, cytosolic DNA, and proteins) may affect and also change the host cell function and immune system. This review summarizes the detailed information about the structure, classification, and pathogenesis mechanism of human endogenous retroviruses and their relationship with the autoimmune diseases and some kinds of cancers.
Relation between parvovirus B19 infection and fetal mortality and spontaneous abortion
Background: Infection with parvovirus B19 may cause fetal losses including spontaneous abortion,
intrauterine fetal death and non-immune hydrops fetalis. The aim of this study is to determine the
frequency of parvovirus B19 in formalin fixed placental tissues in lost fetuses using real-time PCR
method.
Methods: In this cross-sectional study, 100 formalin fixed placental tissues with unknown cause of
fetal death were determined using real-time PCR method after DNA extraction.
Results: Six out of 100 cases (6%) were positive for parvovirus B19 using real-time PCR. Gestational
age of all positive cases was less than 20 weeks with a mean of 12.3 weeks. Three cases have a
history of abortion and all of positive cases were collected in spring. Mean age of positive cases were
28 years.
Conclusion: Parvovirus B19 during pregnancy can infect red precursor cells and induces apoptosis
or lyses these cells that resulting in anemia and congestive heart failure leading to fetal death. Management
of parvovirus B19 infection in pregnant women is important because immediate diagnosis
and transfusion in hydropsic fetuses can decrease the risk of fetal death
Congenital rubella infection in neonatal cord blood samples of newborns in hospitals affiliated to Tehran University of Medical Sciences
Rubella is a disease caused by the rubella virus and it is usually mild and self-limiting. Infection
of a developing fetus is serious and important because the child may be born with congenital
rubella syndrome. Its symptoms include mental retardation, heart defects, cataract, etc.
In 2003, mass vaccination against measles and rubella in individuals 5-25 years old was done.
One of the main objectives of this study was to survey congenital rubella infection status with the
presence of IgM antibodies against rubella virus in cord blood samples and also the immunity
assessment of maternal IgG antibodies against rubella virus in the above samples.
Methods:
The cross-sectional study was to determine the transfer of congenital rubella in 358 cord blood
samples collected in hospitals affiliated to the Tehran University of Medical
Sciences that was done in 2008-2009
The collected samples were analyzed by two ELISA methods for detection of IgG and IgM
antibodies, RT-Nested PCR tests was applied on samples of IgG–negative and IgM-positive and
also some of randomly IgG-positive samples for identifying the presence of the virus genome.
In this study two groups of mothers were tested, one consisted above 29 years of age (at the time
of vaccination) with the frequency of 73.4% and the other one below 29 years of age with the
frequency of 26.6%.Results:
Of the 358 samples, 91.1% IgG and 2.8% were found to be positive. None of the 31 samples
were positive according to the presence of the virus genome via the method of RT-Nested PCR.
Conclusion:
According to high immunity of mothers, the probability of congenital rubella transmission was
low, but because of low immunity of mothers of >29 years of age, it is much better to upgrade
the age of vaccination to 28 years old
Signal transduction pathway mutations in gastrointestinal (GI) cancers : a systematic review and meta-analysis
The present study was conducted to evaluate the prevalence of the signaling pathways mutation rate in the Gastrointestinal (GI) tract cancers in a systematic review and meta-analysis study. The study was performed based on the PRISMA criteria. Random models by confidence interval (CI: 95%) were used to calculate the pooled estimate of prevalence via Metaprop command. The pooled prevalence indices of signal transduction pathway mutations in gastric cancer, liver cancer, colorectal cancer, and pancreatic cancer were 5% (95% CI: 3–8%), 12% (95% CI: 8–18%), 17% (95% CI: 14–20%), and 20% (95% CI: 5–41%), respectively. Also, the mutation rates for Wnt pathway and MAPK pathway were calculated to be 23% (95% CI, 14–33%) and 20% (95% CI, 17–24%), respectively. Moreover, the most popular genes were APC (in Wnt pathway), KRAS (in MAPK pathway) and PIK3CA (in PI3K pathway) in the colorectal cancer, pancreatic cancer, and gastric cancer while they were beta-catenin and CTNNB1 in liver cancer. The most altered pathway was Wnt pathway followed by the MAPK pathway. In addition, pancreatic cancer was found to be higher under the pressure of mutation compared with others based on pooled prevalence analysis. Finally, APC mutations in colorectal cancer, KRAS in gastric cancer, and pancreatic cancer were mostly associated gene alterations
Forecasting influenza hemagglutinin mutations through the lens of anomaly detection
Abstract The influenza virus hemagglutinin is an important part of the virus attachment to the host cells. The hemagglutinin proteins are one of the genetic regions of the virus with a high potential for mutations. Due to the importance of predicting mutations in producing effective and low-cost vaccines, solutions that attempt to approach this problem have recently gained significant attention. A historical record of mutations has been used to train predictive models in such solutions. However, the imbalance between mutations and preserved proteins is a big challenge for the development of such models that need to be addressed. Here, we propose to tackle this challenge through anomaly detection (AD). AD is a well-established field in Machine Learning (ML) that tries to distinguish unseen anomalies from normal patterns using only normal training samples. By considering mutations as anomalous behavior, we could benefit existing rich solutions in this field that have emerged recently. Such methods also fit the problem setup of extreme imbalance between the number of unmutated vs. mutated training samples. Motivated by this formulation, our method tries to find a compact representation for unmutated samples while forcing anomalies to be separated from the normal ones. This helps the model to learn a shared unique representation between normal training samples as much as possible, which improves the discernibility and detectability of mutated samples from the unmutated ones at the test time. We conduct a large number of experiments on four publicly available datasets, consisting of three different hemagglutinin protein datasets, and one SARS-CoV-2 dataset, and show the effectiveness of our method through different standard criteria
Differentiation of Penicillin Susceptible and Nonsusceptible Streptococcus pneumoniae
Introduction: Streptococcus pneumoniae cause morbidity and mortality in infants and younger children. Because of high prevalence of penicillin resistance, rapid and reliable diagnostic techniques for penicillin non-susceptible S. pneumoniae (PNSSP) are important for prevention and treatment. We investigated the association of the restriction length polymorphism (RFLP) patterns for pbp2b to distinguish between penicillin susceptible and resistant S. pneumoniae isolates.Methods: In this study, a total of 70 pneumococcal isolates were collected from different clinical sources. MIC of these isolates was determined and pbp2b gene was amplified by PCR and they were digested by HaeІІІ enzyme.Results: Of the 70 isolates, 86% (60) and 14% (10) pneumococcal isolates were found to be PNSSP (penicillin intermediate S. pneumoniae (PISP) and penicillin resistant S. pneumoniae (PRSP)) and penicillin susceptible S. pneumoniae (PSSP). In addition, 10 RFLP patterns (A-J) which were based on the HaeІІІ digestion of pbp2b gene were observed. All PSSP isolates showed that they belonged to pattern D, whereas, all PNSSP showed 10 different patterns.Conclusion: In general, the present study suggests that RFLP can be a powerful tool in differentiation between the penicillin resistant and susceptible strains.</p
Anti-cancer effects of Bifidobacterium species in colon cancer cells and a mouse model of carcinogenesis.
INTRODUCTION:Probiotics are suggested to prevent colorectal cancer (CRC). This study aimed to investigate the anticancer properties of some potential probiotics in vitro and in vivo. MATERIALS AND METHODS:Anticancer effects of the following potential probiotic groups were investigated in LS174T cancer cells compared to IEC-18 normal cells. 1. a single strain of Bifidobacterium. breve, 2. a single strain of Lactobacillus. reuteri, 3. a cocktail of 5 strains of Lactobacilli (LC), 4. a cocktail of 5 strains of Bifidobacteria (BC), 5. a cocktail of 10 strains from Lactobacillus and Bifidobacterium (L+B). Apoptosis rate, EGFR, HER-2 and PTGS-2 (COX-2 protein) expression levels were assessed as metrics of evaluating anticancer properties. Effect of BC, as the most effective group in vitro, was further assessed in mice models. RESULTS:BC induced ~21% and only ~3% apoptosis among LS174T and IEC-18 cells respectively. BC decreased the expression of EGFR by 4.4 folds, HER-2 by 6.7 folds, and PTGS-2 by 20 folds among the LS174T cells. In all these cases, BC did not interfere significantly with the expression of the genes in IEC-18 cells. This cocktail has caused only 1.1 folds decrease, 1.8 folds increase and 1.7 folds decrease in EGFR, HER-2 and PTGS-2 expression, respectively. Western blot analysis confirmed these results in the protein level. BC significantly ameliorated the disease activity index, restored colon length, inhibited the increase in incidence and progress of tumors to higher stages and grades. CONCLUSIONS:BC was the most efficient treatment in this study. It had considerable "protective" anti-cancer properties and concomitantly down regulated EGFR, HER-2 and PTGS-2 (COX-2), while having significant anti-CRC effects on CRC mice models. In general, this potential probiotic could be considered as a suitable nutritional supplement to treat and prevent CRC
Correction: Anti-cancer effects of Bifidobacterium species in colon cancer cells and a mouse model of carcinogenesis.
[This corrects the article DOI: 10.1371/journal.pone.0232930.]
Mechanisms Involved in Immunopathogenesis of influenza virus infection
Influenza epidemics and pandemics cause notable morbidity and mortality. Mortality cases are mostly associated with immunopathogenic mechanisms, although still poorly understood. Human studies help to understand the immunopathogenesis of influenza. However, there is limited information in this regard. Recent studies using experimental animal models have significantly improved our knowledge on complex mechanisms involved in the immunopathogenesis during influenza infections including acute inflammatory responses of neutrophils, dendritic cells, macrophages, toll-like receptors, chemokines, cytokines, CD4+ and CD8+ T cells. Due to influenza infection, elevated levels of cytokines and chemokines are produced during influenza-induced inflammation which are known as cytokine storm which is a severe immune response characterized by the recruitment of inflammatory leukocytes and increased levels of cytokines and chemokines at the site of infection. This review aimed to discuss the most recent findings on mechanisms of influenza immunopathogenesis.
 
Roles of Integrin and Its Application for Anti-viral Drug Development
Integrins are a large family of adhesion molecules under cellular control that could act bilabially in different situations; on the other hand, they play a significant role in adsorption and entry of immune system cells or other helper cells. Furthermore, they could be good targets for entry, localization and replication of infectious viruses into cells. As viruses apply various strategies for entry and infiltration to cells, comparison of these ways (especially integrin mediated), elucidates effective mechanisms in the inception of viral infection and the host cells interactions. At this point, the present study reviewed the relationships between common viruses such as Adenovirus, Papillomavirus, Herpesvirus, Hantavirus, Rotavirus, Echovirus, foot-and-mouth disease virus, Coxsackievirus type 9, Parechovirus type 1 and Human immunodeficiency virus type 1 with integrins and their viable interactions for therapeutical issues and better recognition of the commencement process of the infection by these viruses