Different gastrointestinal pathogens cause diarrhea which is a very common problem in children ag... more Different gastrointestinal pathogens cause diarrhea which is a very common problem in children aged under 5 years. Among bacterial pathogens, Shigella is one of the main causes of diarrhea among children, and it accounts for approximately 11% of all deaths among children aged under 5 years. The case-fatality rates for Shigella among the infants and children aged 1 to 4 years are 13.9% and 9.4%, respectively. Shigella uses unique effector proteins to modulate intracellular pathways. Shigella cannot invade epithelial cells on the apical site; therefore, it needs to pass epithelium through other cells rather than the epithelial cell. After passing epithelium, macrophage swallows Shigella, and the latter should prepare itself to exhibit at least two types of responses: (I) escaping phagocyte and (II) mediating invasion of and injury to the recurrent PMN. The presence of PMN and invitation to a greater degree resulted in gut membrane injuries and greater bacterial penetration. Infiltrati...
: Formation of Staphylococcus aureus biofilm causes significant infections in the human body. Bio... more : Formation of Staphylococcus aureus biofilm causes significant infections in the human body. Biofilm forms through the aggregation of bacterial species and brings about many complications. It mediates drug resistance and persistence and facilitates the recurrence of infection at the end of antimicrobial therapy. Biofilm formation is completed in a series of steps, and any interference in these steps can disrupt its formation. Such interference may occur at any stage of biofilm production, including attachment, monolayer formation, and accumulation. Interfering agents can act as quorum sensing inhibitors and interfere in the functionality of quorum sensing receptors, attachment inhibitors, and affect cell hydrophobicity. Among these inhibiting strategies, attachment inhibitors could serve as the best agents against biofilm formation, because in case pathogens abort the attachment, the next stages of biofilm formation, e.g., accumulation and dispersion, will fail to materialize. Inhibition at this stage leads to suppression of virulence factors and invasion. One of the best knowing inhibitors is a chelator that collects metal, Fe+, Zn+, and magnesium critical for biofilm formation. These effective factors in the binding and formation of biofilm are investigated, and the coping strategy is discussed. This review examines the stages of biofilm formation and determines what factors interfere in the continuity of these steps. Finally, the inhibition strategies are investigated, reviewed, and discussed.
Background: Since the introduction of NICE glaucoma guidelines 2009, the number of referrals from... more Background: Since the introduction of NICE glaucoma guidelines 2009, the number of referrals from the community optometrists to secondary hospital services(HES) have increased across the UK, resulting in increase in first visit discharge rates(FVDR). Aim: To assess the impact of SIGN 144 on quality of referrals from community optometrists. Methodology: A retrospective case study of 256 electronic records from (TRAK) of patients who attended the new glaucoma clinics in Princess Alexander Eye Pavillion(PAEP) was carried out across Oct-Nov 2014 and Sept-Oct 2016.Patients included were aged from 18 years and above, referred to the PAEP glaucoma outpatients clinic for new glaucoma diagnosis. Primary outcome of this study is FVDR. Secondary outcome is the extent of compliance to recommendations by SIGN guidelines. Results: 104 and 152 patients were included in group 1 and 2 respectively. Our study showed that there is a significant decline in FVDR between these 2 periods.(odds ratio 0.43,...
Coagulase-negative staphylococci (CoNS) are recognized as comprising the main part of human norma... more Coagulase-negative staphylococci (CoNS) are recognized as comprising the main part of human normal microbiota and are rarely associated with severe and intensive infections. However, these organisms can cause a number of infections in humans, especially immunocompromised patients and neonates. Bacterial meningitis, as an important and acute infection in the central nervous system, is still a major global health challenge and a serious infectious disease, causing a high rate of mortality and morbidity. CoNS as causative agents of meningitis are generally related to trauma or direct implantation of foreign bodies and the presence of a cerebrospinal fluid shunt. Numerous epidemiologic and clinical studies have shown that different CoNS isolates such as Staphylococcus capitis, Staphylococcus lugdunensis, Staphylococcus hominis, Staphylococcus epidermidis, Staphylococcus schleiferi, Staphylococcus saprophyticus, Staphylococcus warneri and Staphylococcus haemolyticus are more frequently associated with meningitis. This study attempts to determine the role of CoNS in meningitis and reviews the reported cases of meningitis induced by CoNS from the year 2000 to 2020 in the literature.
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Celiac Disease (CD) is an immune-mediated enteropathy, generally of the proximal intestine, that ... more Celiac Disease (CD) is an immune-mediated enteropathy, generally of the proximal intestine, that occurs in genetically susceptible individuals triggered by the ingestion of gluten. The incidence and frequency of CD are increasing, and it is predicted that CD affects approximately 1% of the people worldwide. The common clinical manifestations of CD are divided in two sections, including classic and non-classic symptoms that can be created in childhood and adulthood. The relationship between pathogenic and non-pathogenic bacteria with CD is complex and multidirectional. In previous published studies, results demonstrated the triggering impact of bacteria, viruses, and parasites on initiation and development of Inflammatory Bowel Disease (IBD) and Irritable Bowel Syndrome (IBS). Different studies revealed the inducing effect of pathogenic and non-pathogenic bacteria on CD. However, increasing evidence proposes that some of these microorganisms can also play several positive roles in CD...
Salmonella can be categorized into many serotypes, which are specific to known hosts or broadhost... more Salmonella can be categorized into many serotypes, which are specific to known hosts or broadhosts. It makes no difference which one of the serotypes would penetrate the gastrointestinal tract because they all face similar obstacles such as mucus and microbiome. However, following their penetration, some species remain in the gastrointestinal tract; yet, others spread to another organ like gallbladder. Salmonella is required to alter the immune response to sustain its intracellular life. Changing the host response requires particular effector proteins and vehicles to translocate them. To this end, a categorized gene called Salmonella pathogenicity island (SPI) was developed; genes like Salmonella pathogenicity island encode aggressive or modulating proteins. Initially, Salmonella needs to be attached and stabilized via adhesin factor, without which no further steps can be taken. In this review, an attempt has been made to elaborate on each factor attached to the host cell or to modulating and aggressive proteins that evade immune systems. This review includes four sections: (A) attachment factors or T3SS-independent entrance, (B) effector proteins or T3SS-dependent entrance, (c) regulation of invasive genes, and (D) regulation of immune responses.
Mycobacterial infections are considered to a serious challenge of medicine, and the emergence of ... more Mycobacterial infections are considered to a serious challenge of medicine, and the emergence of MDR and XDR tuberculosis is a serious public health problem. Tuberculosis can cause high morbidity and mortality around the world, particularly in developing countries. The emergence of drug-resistant Mycobacterium infection following limited therapeutic technologies coupled with the serious worldwide tuberculosis epidemic has adversely affected control programs, thus necessitating the study of the role bacteriophages in the treatment of mycobacterial infection. Bacteriophages are viruses that are isolated from several ecological specimens and do not exert adverse effects on patients. Phage therapy can be considered as a significant alternative to antibiotics for treating MDR and XDR mycobacterial infections. The useful ability of bacteriophages to kill Mycobacterium spp has been explored by numerous research studies that have attempted to investigate the phage therapy as a novel therapeutic/diagnosis approach to mycobacterial infections. However, there are restricted data about phage therapy for treating mycobacterial infections. This review presents comprehensive data about phage therapy in the treatment of mycobacterial infection, specifically tuberculosis disease.
Celiac Disease (CD) is a complex autoimmune enteropathy of the small intestine that commonly occu... more Celiac Disease (CD) is a complex autoimmune enteropathy of the small intestine that commonly occurs in genetically predisposed individuals due to intake of gluten and related proteins. Gluten consumption, duration of breast-feeding, various infections, especially frequent intestinal infections, vaccinations and use of antibiotics can be linked to CD. It is predicted that it affects 1% of the global population and its incidence rate is increasing. Most of the people with the HLA-DQ2 or HLADQ8 are at a higher risk of developing this disease. The link between infections and autoimmune diseases has been very much considered in recent years. In several studies, we explained that pathogenic and non-pathogenic microorganisms might have multiple roles in initiation, exacerbation, and development of Irritable Bowel Syndrome (IBS) and Inflammatory Bowel Disease (IBD). In various studies, the relationship between infections caused by viruses, such as Epstein-Barr Virus (EBV), Rotavirus, Hepati...
Staphylococcus aureus (S.aureus) is a Gram-positive bacterium that causes many infections and dis... more Staphylococcus aureus (S.aureus) is a Gram-positive bacterium that causes many infections and diseases. This pathogen can cause many types of infections such as impetigo, toxic shock syndrome toxin (TSST1), pneumonia, endocarditis, and autoimmune diseases like lupus erythematosus and can infect other healthy individuals. In the pathogenic process, colonization is a main risk factor for invasive diseases. Various factors including the cell wall-associated factors and receptors of the epithelial cells facilitate adhesion and colonization of this pathogen. S. aureus has many enzymes, toxins, and strategies to evade from the immune system either by an enzyme that lyses cellular component or by hiding from the immune system via surface antigens like protein A and second immunoglobulin-binding protein (Sbi). The strategies of this bacterium can be divided into five groups: A: Inhibit neutrophil recruitment B: Inhibit phagocytosis C: Inhibit killing by ROS, D: Neutrophil killing, and E: Resistance to antimicrobial peptide. On the other hand, innate immune system via neutrophils, the most important polymorphonuclear leukocytes, fights against bacterial cells by neutrophil extracellular trap (NET). In this review, we try to explain the role of each factor in immune evasion.
The British journal of ophthalmology, Jan 18, 2018
Since the introduction of National Institute for Health and Care Excellence glaucoma guidelines 2... more Since the introduction of National Institute for Health and Care Excellence glaucoma guidelines 2009, the number of referrals from community optometrists to hospital eye services has increased across the UK, resulting in increase in first visit discharge rates (FVDRs). To assess the impact of Scottish Intercollegiate Guidelines Network (SIGN) 144 on quality of referrals from community optometrists. A retrospective study of patient records who attended as new adult glaucoma referrals to clinics in Princess Alexandra Eye Pavilion, Edinburgh, and in Greater Glasgow and Clyde, was carried out across October-November 2014 (group 1) and September-October 2016 (group 2), before and after the introduction of SIGN 144. The primary outcome of this study is FVDRs. A secondary outcome is the extent of compliance to referral recommendations by SIGN guidelines. Three hundred and twelve and 325 patients were included in groups 1 and 2, respectively. There was a significant decline in FVDRs between...
Different gastrointestinal pathogens cause diarrhea which is a very common problem in children ag... more Different gastrointestinal pathogens cause diarrhea which is a very common problem in children aged under 5 years. Among bacterial pathogens, Shigella is one of the main causes of diarrhea among children, and it accounts for approximately 11% of all deaths among children aged under 5 years. The case-fatality rates for Shigella among the infants and children aged 1 to 4 years are 13.9% and 9.4%, respectively. Shigella uses unique effector proteins to modulate intracellular pathways. Shigella cannot invade epithelial cells on the apical site; therefore, it needs to pass epithelium through other cells rather than the epithelial cell. After passing epithelium, macrophage swallows Shigella, and the latter should prepare itself to exhibit at least two types of responses: (I) escaping phagocyte and (II) mediating invasion of and injury to the recurrent PMN. The presence of PMN and invitation to a greater degree resulted in gut membrane injuries and greater bacterial penetration. Infiltrati...
: Formation of Staphylococcus aureus biofilm causes significant infections in the human body. Bio... more : Formation of Staphylococcus aureus biofilm causes significant infections in the human body. Biofilm forms through the aggregation of bacterial species and brings about many complications. It mediates drug resistance and persistence and facilitates the recurrence of infection at the end of antimicrobial therapy. Biofilm formation is completed in a series of steps, and any interference in these steps can disrupt its formation. Such interference may occur at any stage of biofilm production, including attachment, monolayer formation, and accumulation. Interfering agents can act as quorum sensing inhibitors and interfere in the functionality of quorum sensing receptors, attachment inhibitors, and affect cell hydrophobicity. Among these inhibiting strategies, attachment inhibitors could serve as the best agents against biofilm formation, because in case pathogens abort the attachment, the next stages of biofilm formation, e.g., accumulation and dispersion, will fail to materialize. Inhibition at this stage leads to suppression of virulence factors and invasion. One of the best knowing inhibitors is a chelator that collects metal, Fe+, Zn+, and magnesium critical for biofilm formation. These effective factors in the binding and formation of biofilm are investigated, and the coping strategy is discussed. This review examines the stages of biofilm formation and determines what factors interfere in the continuity of these steps. Finally, the inhibition strategies are investigated, reviewed, and discussed.
Background: Since the introduction of NICE glaucoma guidelines 2009, the number of referrals from... more Background: Since the introduction of NICE glaucoma guidelines 2009, the number of referrals from the community optometrists to secondary hospital services(HES) have increased across the UK, resulting in increase in first visit discharge rates(FVDR). Aim: To assess the impact of SIGN 144 on quality of referrals from community optometrists. Methodology: A retrospective case study of 256 electronic records from (TRAK) of patients who attended the new glaucoma clinics in Princess Alexander Eye Pavillion(PAEP) was carried out across Oct-Nov 2014 and Sept-Oct 2016.Patients included were aged from 18 years and above, referred to the PAEP glaucoma outpatients clinic for new glaucoma diagnosis. Primary outcome of this study is FVDR. Secondary outcome is the extent of compliance to recommendations by SIGN guidelines. Results: 104 and 152 patients were included in group 1 and 2 respectively. Our study showed that there is a significant decline in FVDR between these 2 periods.(odds ratio 0.43,...
Coagulase-negative staphylococci (CoNS) are recognized as comprising the main part of human norma... more Coagulase-negative staphylococci (CoNS) are recognized as comprising the main part of human normal microbiota and are rarely associated with severe and intensive infections. However, these organisms can cause a number of infections in humans, especially immunocompromised patients and neonates. Bacterial meningitis, as an important and acute infection in the central nervous system, is still a major global health challenge and a serious infectious disease, causing a high rate of mortality and morbidity. CoNS as causative agents of meningitis are generally related to trauma or direct implantation of foreign bodies and the presence of a cerebrospinal fluid shunt. Numerous epidemiologic and clinical studies have shown that different CoNS isolates such as Staphylococcus capitis, Staphylococcus lugdunensis, Staphylococcus hominis, Staphylococcus epidermidis, Staphylococcus schleiferi, Staphylococcus saprophyticus, Staphylococcus warneri and Staphylococcus haemolyticus are more frequently associated with meningitis. This study attempts to determine the role of CoNS in meningitis and reviews the reported cases of meningitis induced by CoNS from the year 2000 to 2020 in the literature.
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Celiac Disease (CD) is an immune-mediated enteropathy, generally of the proximal intestine, that ... more Celiac Disease (CD) is an immune-mediated enteropathy, generally of the proximal intestine, that occurs in genetically susceptible individuals triggered by the ingestion of gluten. The incidence and frequency of CD are increasing, and it is predicted that CD affects approximately 1% of the people worldwide. The common clinical manifestations of CD are divided in two sections, including classic and non-classic symptoms that can be created in childhood and adulthood. The relationship between pathogenic and non-pathogenic bacteria with CD is complex and multidirectional. In previous published studies, results demonstrated the triggering impact of bacteria, viruses, and parasites on initiation and development of Inflammatory Bowel Disease (IBD) and Irritable Bowel Syndrome (IBS). Different studies revealed the inducing effect of pathogenic and non-pathogenic bacteria on CD. However, increasing evidence proposes that some of these microorganisms can also play several positive roles in CD...
Salmonella can be categorized into many serotypes, which are specific to known hosts or broadhost... more Salmonella can be categorized into many serotypes, which are specific to known hosts or broadhosts. It makes no difference which one of the serotypes would penetrate the gastrointestinal tract because they all face similar obstacles such as mucus and microbiome. However, following their penetration, some species remain in the gastrointestinal tract; yet, others spread to another organ like gallbladder. Salmonella is required to alter the immune response to sustain its intracellular life. Changing the host response requires particular effector proteins and vehicles to translocate them. To this end, a categorized gene called Salmonella pathogenicity island (SPI) was developed; genes like Salmonella pathogenicity island encode aggressive or modulating proteins. Initially, Salmonella needs to be attached and stabilized via adhesin factor, without which no further steps can be taken. In this review, an attempt has been made to elaborate on each factor attached to the host cell or to modulating and aggressive proteins that evade immune systems. This review includes four sections: (A) attachment factors or T3SS-independent entrance, (B) effector proteins or T3SS-dependent entrance, (c) regulation of invasive genes, and (D) regulation of immune responses.
Mycobacterial infections are considered to a serious challenge of medicine, and the emergence of ... more Mycobacterial infections are considered to a serious challenge of medicine, and the emergence of MDR and XDR tuberculosis is a serious public health problem. Tuberculosis can cause high morbidity and mortality around the world, particularly in developing countries. The emergence of drug-resistant Mycobacterium infection following limited therapeutic technologies coupled with the serious worldwide tuberculosis epidemic has adversely affected control programs, thus necessitating the study of the role bacteriophages in the treatment of mycobacterial infection. Bacteriophages are viruses that are isolated from several ecological specimens and do not exert adverse effects on patients. Phage therapy can be considered as a significant alternative to antibiotics for treating MDR and XDR mycobacterial infections. The useful ability of bacteriophages to kill Mycobacterium spp has been explored by numerous research studies that have attempted to investigate the phage therapy as a novel therapeutic/diagnosis approach to mycobacterial infections. However, there are restricted data about phage therapy for treating mycobacterial infections. This review presents comprehensive data about phage therapy in the treatment of mycobacterial infection, specifically tuberculosis disease.
Celiac Disease (CD) is a complex autoimmune enteropathy of the small intestine that commonly occu... more Celiac Disease (CD) is a complex autoimmune enteropathy of the small intestine that commonly occurs in genetically predisposed individuals due to intake of gluten and related proteins. Gluten consumption, duration of breast-feeding, various infections, especially frequent intestinal infections, vaccinations and use of antibiotics can be linked to CD. It is predicted that it affects 1% of the global population and its incidence rate is increasing. Most of the people with the HLA-DQ2 or HLADQ8 are at a higher risk of developing this disease. The link between infections and autoimmune diseases has been very much considered in recent years. In several studies, we explained that pathogenic and non-pathogenic microorganisms might have multiple roles in initiation, exacerbation, and development of Irritable Bowel Syndrome (IBS) and Inflammatory Bowel Disease (IBD). In various studies, the relationship between infections caused by viruses, such as Epstein-Barr Virus (EBV), Rotavirus, Hepati...
Staphylococcus aureus (S.aureus) is a Gram-positive bacterium that causes many infections and dis... more Staphylococcus aureus (S.aureus) is a Gram-positive bacterium that causes many infections and diseases. This pathogen can cause many types of infections such as impetigo, toxic shock syndrome toxin (TSST1), pneumonia, endocarditis, and autoimmune diseases like lupus erythematosus and can infect other healthy individuals. In the pathogenic process, colonization is a main risk factor for invasive diseases. Various factors including the cell wall-associated factors and receptors of the epithelial cells facilitate adhesion and colonization of this pathogen. S. aureus has many enzymes, toxins, and strategies to evade from the immune system either by an enzyme that lyses cellular component or by hiding from the immune system via surface antigens like protein A and second immunoglobulin-binding protein (Sbi). The strategies of this bacterium can be divided into five groups: A: Inhibit neutrophil recruitment B: Inhibit phagocytosis C: Inhibit killing by ROS, D: Neutrophil killing, and E: Resistance to antimicrobial peptide. On the other hand, innate immune system via neutrophils, the most important polymorphonuclear leukocytes, fights against bacterial cells by neutrophil extracellular trap (NET). In this review, we try to explain the role of each factor in immune evasion.
The British journal of ophthalmology, Jan 18, 2018
Since the introduction of National Institute for Health and Care Excellence glaucoma guidelines 2... more Since the introduction of National Institute for Health and Care Excellence glaucoma guidelines 2009, the number of referrals from community optometrists to hospital eye services has increased across the UK, resulting in increase in first visit discharge rates (FVDRs). To assess the impact of Scottish Intercollegiate Guidelines Network (SIGN) 144 on quality of referrals from community optometrists. A retrospective study of patient records who attended as new adult glaucoma referrals to clinics in Princess Alexandra Eye Pavilion, Edinburgh, and in Greater Glasgow and Clyde, was carried out across October-November 2014 (group 1) and September-October 2016 (group 2), before and after the introduction of SIGN 144. The primary outcome of this study is FVDRs. A secondary outcome is the extent of compliance to referral recommendations by SIGN guidelines. Three hundred and twelve and 325 patients were included in groups 1 and 2, respectively. There was a significant decline in FVDRs between...
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