Global mapping of antibiotic resistance rates among clinical isolates of Stenotrophomonas maltophilia: a systematic review and meta-analysis.

INTRODUCTION: Infections caused by Stenotrophomonas maltophilia are clinically important due to its intrinsic resistance to a broad range of antibiotics. Therefore, selecting the most appropriate antibiotic to treat S. maltophilia infection is a major challenge. AIM: The current meta-analysis aimed to investigate the global prevalence of antibiotic resistance among S. maltophilia isolates to the develop more effective therapeutic strategies. METHOD: A systematic literature search was performed using the appropriate search syntax after searching Pubmed, Embase, Web of Science and Scopus databases (May 2023). Statistical analysis was performed using Pooled and the random effects model in R and the metafor package. A total of 11,438 articles were retrieved. After a thorough evaluation, 289 studies were finally eligible for inclusion in this systematic review and meta-analysis. RESULT: Present analysis indicated that the highest incidences of resistance were associated with doripenem (97%), cefoxitin (96%), imipenem and cefuroxime (95%), ampicillin (94%), ceftriaxone (92%), aztreonam (91%) and meropenem (90%) which resistance to Carbapenems is intrinsic. The lowest resistance rates were documented for minocycline (3%), cefiderocol (4%). The global resistance rate to TMP-SMX remained constant in two periods before and after 2010 (14.4% vs. 14.6%). A significant increase in resistance to tigecycline and ceftolozane/tazobactam was observed before and after 2010. CONCLUSIONS: Minocycline and cefiderocol can be considered the preferred treatment options due to low resistance rates, although regional differences in resistance rates to other antibiotics should be considered. The low global prevalence of resistance to TMP-SMX as a first-line treatment for S. maltophilia suggests that it remains an effective treatment option.

Prevalence of colistin resistance in clinical isolates of Acinetobacter baumannii: a systematic review and meta-analysis.

INTRODUCTION: The development of colistin resistance in Acinetobacter baumannii during treatment has been identified in certain patients, often leading to prolonged or recurrent infections. As colistin, is the last line of therapy for A. baumannii infections that are resistant to almost all other antibiotics, colistin-resistant A. baumannii strains currently represent a significant public health threat, particularly in healthcare settings where there is significant selective pressure. AIM: The aim of this study was to comprehensively determine the prevalence of colistin resistance in A. baumannii from clinical samples. Regional differences in these rates were also investigated using subgroup analyses. METHOD: The comprehensive search was conducted using "Acinetobacter baumannii", "Colistin resistant" and all relevant keywords. A systematic literature search was performed after searching in PubMed, Embase, Web of Science, and Scopus databases up to April 25, 2023. Statistical analysis was performed using Stata software version 17 and sources of heterogeneity were evaluated using I2. The potential for publication bias was explored using Egger's tests. A total of 30,307 articles were retrieved. After a thorough evaluation, 734 studies were finally eligible for inclusion in the present systematic review and meta-analysis. RESULT: According to the results, the prevalence of resistance to colistin among A. baumannii isolates was 4% (95% CI 3-5%), which has increased significantly from 2% before 2011 to 5% after 2012. South America had the highest resistance rate to this antibiotic. The broth microdilution method had the highest level of resistance, while the agar dilution showed the lowest level. CONCLUSIONS: This meta-analysis found a low prevalence of colistin resistance among A. baumannii isolates responsible for infections worldwide from 2000 to 2023. However, there is a high prevalence of colistin-resistant isolates in certain countries. This implies an urgent public health threat, as colistin is one of the last antibiotics available for the treatment of infections caused by XDR strains of A. baumannii.

Potential antibacterial activity and healing effect of topical administration of bone marrow and adipose mesenchymal stem cells encapsulated in collagen-fibrin hydrogel scaffold on full-thickness burn wound infection caused by Pseudomonas aeruginosa.

Burns injuries are prone to hospital-acquired infections, and Pseudomonas aeruginosa is one of the most common causes of mortality and morbidity in patients with burn injuries. Thus, this study aimed to analyze the effects of topical treatment with bone marrow (BM-MSC) and adipose mesenchymal stem cells (AD-MSC) encapsulated in collagen and fibrin scaffolds in a Balb/c model of burn wound infection. Extraction of stem cells from adipose and bone marrow tissue of rats was performed and cells were characterized using standard methods. Then, collagen, fibrin and collagen-fibrin scaffolds were constructed and the extracted cells were encapsulated in all three scaffolds. Then, 3rd degree burn was induced in mice and 1.5 × 108 (CFU/ml) of P. aeruginosa was introduced to the burn wound. Subsequently, after 24 h of inducing wound infection, encapsulated MSCs were introduced as dressings to burn wound infection and microbial load as well as rate of wound infection healing was measured. The results of this study showed that the use of BM-MSC and AD-MSC encapsulated in collagen-fibrin scaffold reduced the bacteria load down to 54 and 21 CFU/gr, respectively (P < 0.05). Moreover, BM-MSC and AD-MSC encapsulated in collagen-fibrin showed 80% and 75% wound healing, respectively (P < 0.05). Also, we found no significant between cell origin and healing. Encapsulation of MSCs into collagen-fibrin scaffolds could be effective not only against P. aeruginosa infection, but also healing and regeneration of burn wound.

Exploring the interplay between Fusobacterium nucleatum with the expression of microRNA, and inflammatory mediators in colorectal cancer.

Background: Fusobacterium nucleatum has been recognized as an important key bacterium in the cause and spread of colorectal carcinogenesis. Nevertheless, the clinical relevance of F. nucleatum in colorectal cancer (CRC) and its effect on immune factors and the tumor microenvironment have not been fully elucidated. Materials and methods: The frequency of F. nucleatum was measured in 100 paired tumor and normal tissue specimens by TaqMan quantification Real-Time Polymerase Chain Reaction (qPCR). The mRNA expression levels of cytokines (IL-6, IL-10, IL-12ß, IL-17, TNF-α, TLR-2, and TLR-4), and miRNAs (miR-21, miR-31) were examined. Eventually, any potential correlations between the molecular and clinicopathological features of the neoplastic samples and the abundance of F. nucleatum were analyzed. Results: The relative frequency of F. nucleatum was significantly increased in cancerous tissue compared to adjacent non-tumor tissues. Furthermore, the high level of F. nucleatum was significantly associated with histological grade III and IV CRC tissues (P = 0.027 and P = 0.022, respectively) and perineural invasion-positive patients (P = 0.037). In addition, the expression levels of IL-6, IL-17, TNF-α,IL-12ß, TLR-2, and TLR-4 as well as miR-21 and miR-31 showed a significant increase in the cancer group. A notable correlation was also observed between the high status of F. nucleatum and the expression of IL-6, TNF-α and miR-21. Conclusion: Our results emphasize the importance of F. nucleatum and changes in the expression of genes involved in CRC. Studying the microbial profile and gene expression changes in CRC patients may be a promising approach to improve screening methods and provide therapeutic strategies.

Association of Lactobacillus, Firmicutes, Bifidobacterium, Clostridium, and Enterococcus with colorectal cancer in Iranian patients.

Background: Colorectal cancer (CRC) is one of the primary causes of cancer-associated deaths worldwide, and growing evidence shows that alteration in the gut microbiota may be a contributing factor to the development and progression of the disease. This study investigates the correlation between CRC and specific intestinal microbiota abundance, including Firmicutes, Lactobacillus, Enterococcus, Clostridium, and Bifidobacterium. Material and methods: In this study, 100 CRC samples and adjacent normal tissues were obtained from Iranian patients. Afterward, we assessed the abundance of the mentioned bacteria in matched tumor and normal tissue samples from 100 CRC patients, by TaqMan quantitative real-time polymerase chain reaction (qPCR). Results: Most of the patients (55 %) had grade II cancer (moderately differentiated), followed by grade III (poorly Differentiated) in 19 %, and the distribution of the tumor location was 65 % in the colon and 35 % in the rectum. Our research showed a substantial difference in the relative abundance of specific bacteria in tumors and healthy tissues. To this end, four genera of bacteria, including Bifidobacterium, Lactobacillus, Clostridium, and Firmicutes, exhibited statistically significant reductions in tumor tissues compared to adjacent normal tissue (p < 0.05). Conversely, Enterococcus demonstrated a statistically significant increase in tumor tissue samples (p < 0.05). Noteworthy, statistical analysis revealed a significant relationship between Enterococcus and prior cancer (p < 0.05). Conclusions: These findings provide significant insight into the complex association between the gut microbiota and CRC and may pave the way for future research on novel screening methods, preventive measures, and therapeutic strategies targeting the gut microbiota in CRC patients.

COVID-19: An Overview of SARS-CoV-2 Variants-The Current Vaccines and Drug Development.

The world is presently in crisis facing an outbreak of a health-threatening microorganism known as COVID-19, responsible for causing uncommon viral pneumonia in humans. The virus was first reported in Wuhan, China, in early December 2019, and it quickly became a global concern due to the pandemic. Challenges in this regard have been compounded by the emergence of several variants such as B.1.1.7, B.1.351, P1, and B.1.617, which show an increase in transmission power and resistance to therapies and vaccines. Ongoing researches are focused on developing and manufacturing standard treatment strategies and effective vaccines to control the pandemic. Despite developing several vaccines such as Pfizer/BioNTech and Moderna approved by the U.S. Food and Drug Administration (FDA) and other vaccines in phase 4 clinical trials, preventive measures are mandatory to control the COVID-19 pandemic. In this review, based on the latest findings, we will discuss different types of drugs as therapeutic options and confirmed or developing vaccine candidates against SARS-CoV-2. We also discuss in detail the challenges posed by the variants and their effect on therapeutic and preventive interventions.

Evaluation of enterotoxigenic Bacteroides fragilis correlation with the expression of cellular signaling pathway genes in Iranian patients with colorectal cancer.

BACKGROUND: Colorectal cancer (CRC) is one of the most common cancers all over the world, and dysbiosis in the gut microbiota may play a role in colorectal carcinogenesis. Bacteroides fragilis can lead to tumorigenesis by changing signaling pathways, including the WNT/ß-catenin pathway. Therefore, in the present study, we investigated the correlation between the enterotoxigenic B. fragilis amount and the expression of signaling pathway genes involved in CRC. MATERIALS AND METHODS: B. fragilis was determined in 30 tumors and adjacent healthy tissues by the qPCR method. Next, the relationship between enterotoxigenic B. fragilis and the expression of signaling pathway genes, including CCND1, TP53, BCL2, BAX, WNT, TCF, AXIN, APC, and CTNNB1 was investigated. Additionally, possible correlations between clinicopathological features of the tumor samples and the abundance of B. fragilis were analyzed. RESULTS: The results showed that B. fragilis was detected in 100% of tumor samples and 86% of healthy tissues. Additionally, enterotoxigenic B. fragilis colonized 47% of all samples, and bft-1 toxin was the most frequently found isotype among the samples. The analysis showed that the high level of B. fragilis has a significant relationship with the high expression of AXIN, CTNNB1, and BCL2 genes. On the other hand, our results did not show any possible correlation between this bacterium and the clinicopathological features of the tumor sample. CONCLUSION: B. fragilis had a higher abundance in the tumor samples than in healthy tissues, and this bacterium may lead to CRC by making changes in cellular signaling pathways and genes. Therefore, to better understand the physiological effects of B. fragilis on the inflammatory response and CRC, future research should focus on dissecting the molecular mechanisms by which this bacterium regulates cellular signaling pathways.

Investigation of drug regimens and treatment outcome in patients with Mycobacterium Simiae: a systematic review.

INTRODUCTION: Mycobacterium simiae (M.simiae), a non-tuberculous mycobacterium (NTM), rare causes infection including localized pulmonary to disseminated disease in immunocompromised patients. An optimal pharmacological management practice has not yet been defined for this infection. This study investigates drug regimens and treatment outcomes in patients with M. simiae to describe different drug regimen with the therapeutic response. AREAS COVERED: The three databases PubMed, Scopus, and Web of science were systematically searched from June 1994 to June 2021 to retrieve relevant articles. The inclusion criterion included studies, which reported treatment outcomes in patients with M. simiae infections. Treatment success was defined as the achievement of culture conversion, and the improvement of the symptoms and radiologic signs among the patients. EXPERT OPINION: Data of 223 patients were retrieved from 40 studies. Duration of the treatment regimens used in different studies ranged from 2 to 12 months. The most common treatment regimens administered for M. simiae infection were as follows: clarithromycin, rifampin, ethambutol, moxifloxacin, or ciprofloxacin and amikacin plus cotrimoxazole or pyrazinamide in some regimens. Macrolides, such as clarithromycin, combined with quinolones (such as moxifloxacin) and TMP/SMX, which are used in combination, had the most significant effect on eliminating the pulmonary signs of M. simiae.

Mutation in mgrB is the major colistin resistance mechanism in Klebsiella pneumoniae clinical isolates in Tehran, Iran.

Colistin is considered as one of a last resort antimicrobial agent against multidrug-resistant Gram-negative bacteria including Escherichia coli and Klebsiella pneumoniae. However, the recent emergence of colistin resistance (ColR) worldwide that severely restricts therapeutic options is a serious threat to global public health. In this study we have investigated the molecular determinants in ColR K. pneumoniae isolates collected from clinical specimens. A total of 98 E. coli and 195 K. pneumoniae clinical isolates were collected from two hospitals from August 2018 to December 2019 in Tehran, Iran. Colistin susceptibility and minimum inhibitory concentrations (MIC) were determined according to the Clinical and Laboratory Standards Institute by disk diffusion method, and microdilution method, respectively. For isolates with colistin MIC ≥4 µg mL-1, PCR was performed for the detection of mcr-1 to mcr-4 genes. Moreover, nucleotide sequences of mgrB, phoP, phoQ, pmrA, and pmrB genes were determined by sequencing. Finally, the transcriptional level of pmrK and pmrC genes was evaluated by quantitative reverse transcription PCR (RT-qPCR). None of the E. coli isolates were resistant to colistin while 21 out 195 K. pneumoniae isolates were identified as resistant, 19 of which carried mutation in the mgrB gene. Three different mutations were observed in the pmrB gene in 3 K. pneumoniae isolates. None of the ColR isolates showed alternations in pmrA, phoP, and phoQ genes. Furthermore, none of the plasmid-encoding genes were detected. Transcriptional level of the pmrK gene increased in all ColR isolates meanwhile, pmrC overexpression was detected in 16 out 21 (76.19%) isolates. Eventually, all ColR isolates were susceptible to tigecycline. Our results demonstrated that the alternation of mgrB gene is the main mechanism related to colistin resistance among ColR K. pneumoniae isolates in this study.

The application of selenium nanoparticles for enhancing the efficacy of photodynamic inactivation of planktonic communities and the biofilm of Streptococcus mutans.

OBJECTIVE: Streptococcus mutans is one of the principal causative agents of dental caries (tooth decay) found in the oral cavity. Therefore, this study investigates whether selenium nanoparticles (SeNPs) enhance the efficacy of photodynamic therapy (PDT) against both planktonic communities and the one-day-old biofilm of S. mutans. In this study, the planktonic and 24-h biofilm of S. mutans have been prepared in 96-cell microplates. These forms were treated by methylene blue (MB) and SeNPs and then were exposed to light-emitting diode (LED) lighting. Finally, the results have been reported as CFU/ml. RESULTS: The outcomes demonstrated that MB-induced PDT and SeNPs significantly reduced the number of planktonic bacteria (P-value < 0.001). The comparison between the treated and untreated groups showed that combining therapy with SeNPs and PDT remarkably decreased colony-forming units of one-day-old S. mutans biofilm (P-value < 0.05). The findings revealed that PDT modified by SeNPs had a high potential to destroy S. mutans biofilm. This combination therapy showed promising results to overcome oral infection in dental science.

Novel strategies for inhibition of bacterial biofilm in chronic rhinosinusitis.

An important role has been recently reported for bacterial biofilm in the pathophysiology of chronic diseases, such as chronic rhinosinusitis (CRS). CRS, affecting sinonasal mucosa, is a persistent inflammatory condition with a high prevalence around the world. Although the exact pathological mechanism of this disease has not been elicited yet, biofilm formation is known to lead to a more significant symptom burden and major objective clinical indicators. The high prevalence of multidrug-resistant bacteria has severely restricted the application of antibiotics in recent years. Furthermore, systemic antibiotic therapy, on top of its insufficient concentration to eradicate bacteria in the sinonasal biofilm, often causes toxicity, antibiotic resistance, and an effect on the natural microbiota, in patients. Thus, coming up with alternative therapeutic options instead of systemic antibiotic therapy is emphasized in the treatment of bacterial biofilm in CRS patients. The use of topical antibiotic therapy and antibiotic eluting sinus stents that induce higher antibiotic concentration, and decrease side effects could be helpful. Besides, recent research recognized that various natural products, nitric oxide, and bacteriophage therapy, in addition to the hindered biofilm formation, could degrade the established bacterial biofilm. However, despite these improvements, new antibacterial agents and CRS biofilm interactions are complicated and need extensive research. Finally, most studies were performed in vitro, and more preclinical animal models and human studies are required to confirm the collected data. The present review is specifically discussing potential therapeutic strategies for the treatment of bacterial biofilm in CRS patients.

The controversial association of gut and urinary microbiota with kidney stone formation.

Nephrolithiasis (kidney stones) is one of the most common chronic kidney diseases that are typically more common among adult men comparing to adult women. The prevalence of this disease is increasing which is influenced by genetic and environmental factors. Kidney stones are mainly composed of calcium oxalate and urinary oxalate which is considered a dangerous factor in their formation. Besides diverse leading reasons in the progression of nephrolithiasis, the gut and urinary microbiome has been recognized as a major player in the development or prevention of it. These microbes produce metabolites that have diverse effects on host biological functions. Therefore, Changes in the composition and structure of the microbiome (dysbiosis) have been implicated in various diseases. The present review focuses on the roles of gut and urinary in kidney stone formation.

The Global Prevalence of Daptomycin, Tigecycline, and Linezolid-Resistant Enterococcus faecalis and Enterococcus faecium Strains From Human Clinical Samples: A Systematic Review and Meta-Analysis.

Background and Aim: The predominant species of the Enterococcus, Enterococcus faecalis (E. faecalis) and Enterococcus faecium (E. faecium) cause great variety of infections. Therefore, the expansion of antimicrobial resistance in the Enterococcus is one of the most important global concerns. This study was conducted to investigate the prevalence of resistance to linezolid, tigecycline, and daptomycin among enterococcal strains isolated from human clinical specimens worldwide. Methods: Several databases including Web of Science, EMBASE, and Medline (via PubMed), were carefully searched and reviewed for original research articles available in databases and published between 2000 and 2020. A total of 114 studies worldwide that address E. faecalis and E. faecium resistance to linezolid, tigecycline, and daptomycin were analyzed by STATA software. Results: The overall prevalence of antibiotic-resistant E. faecalis and E. faecium was reported to be 0.9 and 0.6%, respectively. E. faecalis and E. faecium were more resistant to the linezolid (2.2%) and daptomycin (9%), respectively. The prevalence of tigecyline-resistant E. facium (1%) strains was higher than E. faecalis strains (0.3%). Accordingly, the prevalence of linezolid-resistant E. faecalis was higher in Asia (2.8%), while linezolid-resistant E. faecium was higher in the America (3.4%). Regarding tigecycline-resistance, a higher prevalence of E. faecalis (0.4%) and E. faecium (3.9%) was reported in Europe. Conclusion: In conclusion, this meta-analysis shows that there is an emerging resistance in Enterococcus strains. Despite the rising resistance of enterococci to antibiotics, our results demonstrate that tigecycline, daptomycin, and linezolid can still be used for the treatment of enterococcal infections worldwide.

Prevalence and molecular mechanisms of colistin resistance in Acinetobacter baumannii clinical isolates in Tehran, Iran.

Colistin is one of the last remaining active antibiotics against multidrug resistant Gram-negative bacteria. However, several recent studies reported colistin-resistant (ColR) Acinetobacter baumannii from different countries. In the current study, we investigated molecular mechanisms involved in colistin resistance in A. baumannii isolates from different clinical samples.A total of 110 clinical A. baumannii isolates were collected from two hospitals in Tehran. Minimum inhibitory concentrations (MICs) were determined by broth microdilution according to the Clinical and Laboratory Standards Institute. For the ColR isolates, mutation was detected in pmrA, pmrB, lpxA, lpxC, and lpxD genes using the polymerase chain reaction (PCR) and sequencing. Moreover, the relative expression of the pmrC gene was calculated using quantitative reverse transcription PCR. Three colistin resistant isolates were identified with MIC between 8 and 16 µg/mL and were resistant to all the tested antimicrobial agents. All the three isolates had a mutation in the pmrB, pmrA, lpxA, lpxD, and lpxC genes. Moreover, the overexpression of pmrC gene was observed in all isolates. Our results showed that the upregulation of the PmrAB two component system was the primary mechanism linked to colistin resistance among the studied colistin resistant A. baumannii isolates.

Antimicrobial effects of selenium nanoparticles in combination with photodynamic therapy against Enterococcus faecalis biofilm.

BACKGROUND: Selenium Nanoparticles (SeNPs) were reported as an agent that may enhance the effectiveness of Photodynamic Antimicrobial Chemotherapy (PACT). This in vitro study evaluates the effect of SeNPs on the efficacy of Methylene Blue (MB)-induced PACT against the biofilm formated in 96-well plates and the dentine tubule biofilm of Enterococcus faecalis. METHODS: Chitosan coated SeNPs were synthesized using chemical reduction method and were characterized by Transmission Electron Microscope (TEM) and Dynamic Light Scattering (DLS). Twenty-four-hour biofilms of E. faecalis were developed on 96-well plates and treated with SeNPs, MB, and Light-Emitting Diode (LED). Also, three-week biofilms of E. faecalis were formed on 67 specimens of dentinal tubules, and the antibacterial effects of MB+SeNPs on these biofilms were studied. RESULTS: The average hydrodynamic diameter of SeNPs was 80/3 nm according to DLS measurement. The combined use of MB and SeNPs significantly reduced Colony-Forming Units (CFUs) of one-day-old E. faecalis biofilms in comparison with the control group (P value < 0.05). Besides, combination therapy had the most antibacterial effect on root canal E. faecalis biofilms at both 200 and 400 µm depths of dentine tubules (P value < 0.001). Of note, about 50% of human fibroblast cells survived at a concentration of 128 µg/ml of SeNPs, compared to the control group. CONCLUSION: The results demonstrated that the photodynamic therapy modified by SeNPs could be an effective disinfection alternative to the destruction of E. faecalis biofilms and root canal treatment.

Association between colorectal cancer and Fusobacterium nucleatum and Bacteroides fragilis bacteria in Iranian patients: a preliminary study.

BACKGROUND AND AIM: Recent studies have proposed that commensal bacteria might be involved in the development and progression of gastrointestinal disorders such as colorectal cancer (CRC). Therefore, in this study, the relative abundance of Fusobacterium nucleatum, Bacteroides fragilis, Streptococcus bovis/gallolyticus, and Enteropathogenic Escherichia coli (EPEC) in CRC tissues, and their association with clinicopathologic characteristics of CRC was investigated in Iranian patients. Moreover, the role of these bacteria in the CRC-associated mutations including PIK3CA, KRAS, and BRAF was studied. METHOD: To these ends, the noted bacteria were quantified in paired tumors and normal tissue specimens of 30 CRC patients, by TaqMan quantitative Real-Time Polymerase Chain Reaction (qPCR). Next, possible correlations between clinicopathologic factors and mutations in PIK3CA, KRAS, and BRAF genes were analyzed. RESULTS: In studied samples, B. fragilis was the most abundant bacteria that was detected in 66 and 60% of paired tumor and normal samples, respectively. Furthermore, 15% of the B. fragilis-positive patients were infected with Enterotoxigenic B. fragilis (ETBF) in both adenocarcinoma and matched adjacent normal samples. F. nucleatum was also identified in 23% of tumors and 13% of adjacent normal tissue samples. Moreover, the relative abundance of these bacteria determined by 2-ΔCT was significantly higher in CRC samples than in adjacent normal mucosa (p < 0.05). On the other hand, our findings indicated that S. gallolyticus and EPEC, compared to adjacent normal mucosa, were not prevalent in CRC tissues. Finally, our results revealed a correlation between F. nucleatum-positive patients and the KRAS mutation (p = 0.02), while analyses did not show any association between bacteria and mutation in PIK3CA and BRAF genes. CONCLUSION: The present study is the first report on the analysis of different bacteria in CRC tissue samples of Iranian patients. Our findings revealed that F. nucleatum and B. fragilis might be linked to CRC. However, any link between gut microbiome dysbiosis and CRC remains unknown.

An overview of possible pathogenesis mechanisms of Alternaria alternata in chronic rhinosinusitis and nasal polyposis.

Chronic Rhinosinusitis (CRS) is a multifactorial disease, and different etiologies like metabolism and immunity disorders, bacterial superantigens, biofilms, and fungal allergens are known to develop this disease, especially the CRS with nasal polyps. Alternaria alternata (Alternaria) is one of the most prevalent airborne fungal species in the nasal discharge, which might have vigorous immunologic activities in nasal epithelial cells and play an essential role in the pathogenesis of CRS. Moreover, the interaction between this fungus and the innate and adaptive immune systems leads to the development of chronic inflammation. This inflammation may consequently instigate the CRS and nasal polyposis. The attenuation of surfactant protein synthesis or intracellular reserves and mucus hypersecretion could prevent the clearance of Alternaria from sinuses and may be correlated with colonization and re-infection of airborne fungi. Furthermore, higher expression of cathelicidin, thymic stromal lymphopoietin, toll-like receptors, and T helper 2-dominant immune responses can result in an IgE-mediated pathway activation and eosinophils degranulation. Moreover, higher local Alternaria-specific IgE was shown to be correlated with eosinophilic cationic proteins and might relate to nasal polyps. However, the role of genetic and environmental factors affecting CRS and nasal polyposis is not well studied. Likewise, further animal and clinical studies are required to better understand the role of Alternaria in CRS disease. The current article reviews the recent findings around the Alternaria-induced CRS and nasal polyposis.

The Effects of Antioxidant Vitamins on Proinflammatory Cytokines and Some Biochemical Parameters of Power Plant Workers: A Double-Blind Randomized Controlled Clinical Trial.

Some epidemiological studies have suggested that exposure to extremely low-frequency magnetic fields (ELF-MFs) can affect the immune system. This study aimed to investigate the effects of antioxidant vitamin consumption on proinflammatory cytokines and biochemical parameters changes. In this randomized, controlled double-blinded trial study, power plant workers exposed to ELF-MFs were enrolled based on inclusion criteria. Ninety-one eligible subjects were randomly divided into four groups: the first group (400 units of vitamin E/day), second group (1,000 mg of vitamin C/day), third group (400 units of vitamin E and 1,000 mg of vitamin C/day), and control group. The intervention was conducted for 3 months. Proinflammatory cytokines interleukin-1ß (IL-1ß), IL-6, and tumor necrosis factor-α (TNF-α), and biochemical parameters (fasting blood sugar, total cholesterol, triglyceride, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol [HDL-c], total protein, and albumin) were measured among the participants' serums, before and after the intervention. The mean level of IL-6 in all vitamin-receiving groups, the mean level of IL-1ß in vitamin C and E&C groups, and the mean level of TNF-α in the vitamin C group, decreased significantly after intervention. The arithmetic means of the effect sizes for IL-1ß, IL-6, and TNF-α were 0.71, 0.57, and 0.2, respectively. The level of HDL-c in the vitamin E and vitamin E&C groups and the level of triglyceride in the vitamin C group significantly increased after the intervention. Taking antioxidant vitamins can prevent an increase of proinflammatory cytokines induced by prolonged exposure to ELF-MFs. Bioelectromagnetics. 2021;42:18-26. © 2020 Bioelectromagnetics Society.

Mycobacterium tuberculosis and SARS-CoV-2 Coinfections: A Review.

BACKGROUND: Tuberculosis (TB) is still one of the most important causes of death worldwide. The lack of timely attention on TB diagnosis and treatment during the coronavirus disease 2019 (COVID-19) pandemic is a potential threat to health issues and may have severe consequences for patients and health systems. There is not much information on the management of TB during this period. Here, we reviewed the current literature to evaluate the rate of Mycobacterium tuberculosis and severe acute respiratory syndrome coronavirus 2 coinfections and interactions between these infectious agents. METHODS: Several databases, including Web of Science, Scopus, and MEDLINE (via PubMed), were searched for original articles addressing TB and COVID-19 diseases published from December 2019 to April 2021. RESULTS: Of 3,879 articles, 57 articles were included in this study, and among 106,033 patients affected by COVID-19, 891 also had TB. Overall, investigators found a consistent increase in C-reactive protein, D-dimer (especially in patients with severe clinical manifestation), erythrocyte sedimentation rate, lactate dehydrogenase, alanine aminotransferase, and a reduction of lymphocytes. The respiratory symptoms of TB/COVID-19 patients were similar to those of TB patients, but the risk of developing pulmonary TB increased in COVID-19 patients. Also, the mortality rate in TB/COVID-19 patients was higher than that in patients affected only by COVID-19 or TB. CONCLUSION: Some reports indicated worsening respiratory symptoms and even activation of latent TB after COVID-19 or vice versa. It seems that both active and previously treated TB constituted a risk factor for COVID-19 in terms of severity and mortality, regardless of other underlying diseases and patient status. Health systems should not neglect TB during this era of the ongoing COVID-19 pandemic by setting up appropriate diagnostic and clinical management algorithms.