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1.
Arch Microbiol ; 206(7): 287, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38833010

RESUMO

Hepcidin is a crucial regulator of iron homeostasis with protective effects on liver fibrosis. Additionally, gut microbiota can also affect liver fibrosis and iron metabolism. Although the hepatoprotective potential of Akkermansia muciniphila and Faecalibacterium duncaniae, formerly known as F. prausnitzii, has been reported, however, their effects on hepcidin expression remain unknown. We investigated the direct and macrophage stimulation-mediated effects of active, heat-inactivated, and cell-free supernatant (CFS) forms of A. muciniphila and F. duncaniae on hepcidin expression in HepG2 cells by RT-qPCR analysis. Following stimulation of phorbol-12-myristate-13-acetate (PMA) -differentiated THP-1 cells with A. muciniphila and F. duncaniae, IL-6 concentration was assessed via ELISA. Additionally, the resulting supernatant was treated with HepG2 cells to evaluate the effect of macrophage stimulation on hepcidin gene expression. The expression of genes mediating iron absorption and export was also examined in HepG2 and Caco-2 cells via RT-qPCR. All forms of F. duncaniae increased hepcidin expression while active and heat-inactivated/CFS forms of A. muciniphila upregulated and downregulated its expression, respectively. Active, heat-inactivated, and CFS forms of A. muciniphila and F. duncaniae upregulated hepcidin expression, consistent with the elevation of IL-6 released from THP-1-stimulated cells as a macrophage stimulation effect in HepG2 cells. A. muciniphila and F. duncaniae in active, inactive, and CFS forms altered the expression of hepatocyte and intestinal iron-mediated absorption /exporter genes, namely dcytb and dmt1, and fpn in HepG2 and Caco-2 cells, respectively. In conclusion, A. muciniphila and F. duncaniae affect not only directly but also through macrophage stimulation the expression of hepcidin gene in HepG2 cells. These findings underscore the potential of A. muciniphila and F. duncaniae as a potential therapeutic target for liver fibrosis by modulating hepcidin and intestinal and hepatocyte iron metabolism mediated gene expression.


Assuntos
Akkermansia , Hepcidinas , Macrófagos , Humanos , Hepcidinas/genética , Hepcidinas/metabolismo , Células Hep G2 , Células CACO-2 , Macrófagos/imunologia , Macrófagos/microbiologia , Macrófagos/metabolismo , Células THP-1 , Ferro/metabolismo , Interleucina-6/metabolismo , Interleucina-6/genética , Ativação de Macrófagos , Microbioma Gastrointestinal
2.
Ann Clin Microbiol Antimicrob ; 23(1): 36, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38664815

RESUMO

BACKGROUND: Tuberculosis (TB) continues to pose a threat to communities worldwide and remains a significant public health issue in several countries. We assessed the role of heteroresistance and efflux pumps in bedaquiline (BDQ)-resistant Mycobacterium tuberculosis isolates. METHODS: Nineteen clinical isolates were included in the study, of which fifteen isolates were classified as MDR or XDR, while four isolates were fully susceptible. To evaluate BDQ heteroresistance, the Microplate Alamar Blue Assay (MABA) method was employed. For screening mixed infections, MIRU-VNTR was performed on clinical isolates. Mutations in the atpE and Rv0678 genes were determined based on next-generation sequencing data. Additionally, real-time PCR was applied to assess the expression of efflux pump genes in the absence and presence of verapamil (VP). RESULTS: All 15 drug-resistant isolates displayed resistance to BDQ. Among the 19 total isolates, 21.05% (4/19) exhibited a heteroresistance pattern to BDQ. None of the isolates carried a mutation of the atpE and Rv0678 genes associated with BDQ resistance. Regarding the MIRU-VNTR analysis, most isolates (94.73%) showed the Beijing genotype. Fifteen (78.9%) isolates showed a significant reduction in BDQ MIC after VP treatment. The efflux pump genes of Rv0676c, Rv1258c, Rv1410c, Rv1634, Rv1819, Rv2459, Rv2846, and Rv3065 were overexpressed in the presence of BDQ. CONCLUSIONS: Our results clearly demonstrated the crucial role of heteroresistance and efflux pumps in BDQ resistance. Additionally, we established a direct link between the Rv0676c gene and BDQ resistance. The inclusion of VP significantly reduced the MIC of BDQ in both drug-susceptible and drug-resistant clinical isolates.


Assuntos
Antituberculosos , Diarilquinolinas , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/efeitos dos fármacos , Diarilquinolinas/farmacologia , Humanos , Antituberculosos/farmacologia , Irã (Geográfico) , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Mutação , Proteínas de Membrana Transportadoras/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Farmacorresistência Bacteriana Múltipla/genética , Verapamil/farmacologia
3.
Cost Eff Resour Alloc ; 21(1): 68, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37726829

RESUMO

BACKGROUND: Tuberculosis (TB) is a communicable disease that is a major cause of death and one of the leading causes of death worldwide. Currently, there is no analyzed data to examine the financial profile of TB by country, continent, and year; this article analyzed TB prevention, diagnosis, and treatment financial profile during the last two decades. METHODS: Original research, reviews, and governmental databases are analyzed to present the financial profile of TB. RESULTS: Analyzed data showed Europe (23137.133), Asia (20137.073), and Africa (15237.973) had the most allocated funds (US $ million), and Oceania (236.702), and America (4745.043) had the lowest allocated fund (US $ million) during 2006-2021. Additionally, the allocation of funds (domestic funds, global funds, and grants [excluding global funds]) in different countries and proper planning for TB eradication has caused that in the last two decades, the slope of the confirmed cases and deaths graph line is negative. CONCLUSION: The number of confirmed cases and deaths reported globally is decreasing. The trend lines showed that the assigned funds are increasing, indicating that the TB eradication plan can be apprehended soon.

4.
Ann Clin Microbiol Antimicrob ; 22(1): 18, 2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36829156

RESUMO

BACKGROUND: Carbapenem-resistant Klebsiella pneumoniae (CRKP) is a significant clinical problem, given the lack of therapeutic options. The CRKP strains have emerged as an essential worldwide healthcare issue during the last 10 years. Global expansion of the CRKP has made it a significant public health hazard. We must consider to novel therapeutic techniques. Bacteriophages are potent restorative cases against infections with multiple drug-resistant bacteria. The Phages offer promising prospects for the treatment of CRKP infections. OBJECTIVE: In this study, a novel K. pneumoniae phage vB_KshKPC-M was isolated, characterized, and sequenced, which was able to infect and lyse Carbapenem-resistant K. pneumoniae host specifically. METHODS: One hundred clinical isolates of K. pneumoniae were collected from patients with COVID-19 associated with ventilator-associated acute pneumonia hospitalized at Shahid Beheshti Hospital, Kashan, Iran, from 2020 to 2021. Initially, all samples were cultured, and bacterial isolates identified by conventional biochemical tests, and then the ureD gene was used by PCR to confirm the isolates. The Antibiotic susceptibility test in the disc diffusion method and Minimum inhibitory concentrations for Colistin was done and interpreted according to guidelines. Phenotypic and molecular methods determined the Carbapenem resistance of isolates. The blaKPC, blaNDM, and blaOXA-23 genes were amplified for this detection. Biofilm determination of CRKP isolates was performed using a quantitative microtiter plate (MTP) method. The phage was isolated from wastewater during the summer season at a specific position from Beheshti Hospital (Kashan, Iran). The sample was processed and purified against the bacterial host, a CRKP strain isolated from a patient suffering from COVID-19 pneumoniae and resistance to Colistin with high potency for biofilm production. This isolate is called Kp100. The separated phages were diluted and titration by the double overlay agar plaque assay. The separate Phage is concentrated with 10% PEG and stored at -80 °C until use. The phage host range was identified by the spot test method. The purified phage morphology was determined using a transmission electron microscope. The phage stability tests (pH and temperature) were analyzed. The effect of cationic ions on phage adsorption was evaluated. The optimal titer of bacteriophage was determined to reduce the concentration of the CRKP strain. One-step growth assays were performed to identify the purified phage burst's latent cycle and size. The SDS-PAGE was used for phage proteins analysis. Phage DNA was extracted by chloroform technique, and the whole genome of lytic phage was sequenced using Illumina HiSeq technology (Illumina, San Diego, CA). For quality assurance and preprocessing, such as trimming, Geneious Prime 2021.2.2 and Spades 3.9.0. The whole genome sequence of the lytic phage is linked to the GenBank database accession number. RASTtk-v1.073 was used to predict and annotate the ORFs. Prediction of ORF was performed using PHASTER software. ResFinder is used to assess the presence of antimicrobial resistance and virulence genes in the genome. The tRNAs can-SE v2.0.6 is used to determine the presence of tRNA in the genome. Linear genome comparisons of phages and visualization of coding regions were performed using Easyfig 2.2.3 and Mauve 2.4.0. Phage lifestyles were predicted using the program PHACTS. Phylogenetic analysis and amino acid sequences of phage core proteins, such as the major capsid protein. Phylogenies were reconstructed using the Neighbor-Joining method with 1000 bootstrap repeat. HHpred software was used to predict depolymerase. In this study, GraphPad Prism version 9.1 was used for the statistical analysis. Student's t-test was used to compare the sets and the control sets, and the significance level was set at P ≤ 0.05. RESULTS: Phage vB_KshKPC-M is assigned to the Siphoviridae, order Caudovirales. It was identified as a linear double-stranded DNA phage of 54,378 bp with 50.08% G + C content, had a relatively broad host range (97.7%), a short latency of 20 min, and a high burst size of 260 PFU/cell, and was maintained stable at different pH (3-11) and temperature (45-65 °C). The vB_KshKPC-M genome contains 91 open-reading frames. No tRNA, antibiotic resistance, toxin, virulence-related genes, or lysogen-forming gene clusters were detected in the phage genome. Comparative genomic analysis revealed that phage vB_KshKPC-M has sequence similarity to the Klebsiella phages, phage 13 (NC_049844.1), phage Sushi (NC_028774.1), phage vB_KpnD_PeteCarol (OL539448.1) and phage PWKp14 (MZ634345.1). CONCLUSION: The broad host range and antibacterial activity make it a promising candidate for future phage therapy applications. The isolated phage was able to lyse most of the antibiotic-resistant clinical isolates. Therefore, this phage can be used alone or as a phage mixture in future studies to control and inhibit respiratory infections caused by these bacteria, especially in treating respiratory infections caused by resistant strains in sick patients.


Assuntos
Bacteriófagos , COVID-19 , Infecções por Klebsiella , Klebsiella pneumoniae , Humanos , Antibacterianos/farmacologia , Carbapenêmicos/farmacologia , Colistina/farmacologia , COVID-19/complicações , Genômica , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/virologia , Filogenia , Ventiladores Mecânicos
5.
Anaerobe ; 83: 102786, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37797929

RESUMO

OBJECTIVES: A better understanding of host-microbe interactions as a cross-talk between the gastrointestinal (GI) tract and the gut microbiota can help treat and prevent GI disorders by improving the maintenance of GI homeostasis. The gut microbiota can affect signaling molecules, such as serotonin, which regulates endocrine systems through the GI tract. Moreover, studying the effects of gut microbiota in the small intestine on the human GI tract health is pivotal. METHODS: Male C57BL/6J mice (n = 30, 10 mice per group) were orally gavaged with 200 µL of PBS (control group); mice in group II were orally gavaged with 109 colony-forming units (CFU)/200 µL of viable A. muciniphila, suspended in PBS (A. muciniphila group); and mice in group III were orally gavaged with 10 µg of protein/200 µL of EVs (A. muciniphila-EV group) once daily for four weeks. The gene expression of serotonin system-related genes (Slc6a4, Tph1, Mao, Htr3, Htr4, and Htr7) was examined by quantitative real-time PCR (qPCR) method. RESULTS: Based on the results, A. muciniphila significantly affected the mRNA expression of genes related to the serotonin system (Tph1, Mao, Htr3B, and Htr7) in the duodenum and (Htr3B, Htr4 and Htr7) in the ileum of mice (P < 0.05). Moreover, A. muciniphila-derived EVs affected the expression of major genes related to the serotonin system (Tph1, slc6a4a, Mao, Htr3B, Htr4, and Htr7) in the duodenum and ileum of mice (P < 0.05). CONCLUSIONS: The present findings may pave the way for further investigation of the effects of strain-specific probiotics on the serotonergic system, which is currently in its infancy.


Assuntos
Vesículas Extracelulares , Serotonina , Camundongos , Masculino , Humanos , Animais , Serotonina/metabolismo , Camundongos Endogâmicos C57BL , Verrucomicrobia/fisiologia , Intestino Delgado , Expressão Gênica , Monoaminoxidase/genética , Monoaminoxidase/metabolismo
6.
BMC Biotechnol ; 22(1): 31, 2022 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-36307814

RESUMO

BACKGROUND: Staphylococcal superantigens are virulence factors that help the pathogen escape the immune system and develop an infection. Toxic shock syndrome toxin (TSST)-1 is one of the most studied superantigens whose role in toxic shock syndrome and some particular disorders have been demonstrated. Inhibiting TSST-1 production with antibiotics and targeting TSST-1 with monoclonal antibodies might be one of the best strategies to prevent TSST-1-induced cytokines storm followed by lethality. RESULTS: A novel single-chain variable fragment (scFv), MS473, against TSST-1 was identified by selecting an scFv phage library on the TSST-1 protein. The MS473 scFv showed high affinity and specificity for TSST-1. Moreover, MS473 could significantly prevent TSST-1-induced mitogenicity (the IC50 value: 1.5 µM) and cytokine production. CONCLUSION: Using traditional antibiotics with an anti-TSST-1 scFv as a safe and effective agent leads to deleting the infection source and preventing the detrimental effects of the toxin disseminated into the whole body.


Assuntos
Anticorpos de Cadeia Única , Humanos , Anticorpos de Cadeia Única/farmacologia , Anticorpos de Cadeia Única/metabolismo , Staphylococcus aureus , Superantígenos/metabolismo , Superantígenos/farmacologia , Enterotoxinas , Citocinas/metabolismo , Antibacterianos/farmacologia
7.
BMC Microbiol ; 22(1): 96, 2022 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-35410123

RESUMO

BACKGROUND: Mycobacterium fortuitum (M. fortuitum) is a bacterium, which can cause infections in many anatomical regions of the body, including the skin, lymph nodes, and joints. This bacterium, which belongs to a group of bacteria known as nontuberculous mycobacteria, is regarded as an important nosocomial pathogen worldwide owing to its increasing antibiotic resistance. Recently, the antimicrobial effects of carbon nanotubes have been reported in numerous studies. These nanotubes can be very useful in drug delivery; besides, they exhibit unique properties against multidrug-resistant bacterial infections. This study aimed to investigate the antimicrobial effects of carboxyl-functionalized multi-walled carbon nanotubes (MWCNT-COOH) to reduce antibiotic resistance. METHODS: In this study, antibacterial effects of nanofluids containing functionalized MWCNTs at initial concentration of 2 mg/mL and serial dilutions of 54, 28.5, 14.25, 7.12, 3.5 µg/mL, antibiotics alone and combination of nanofluids with antibiotics were investigated. Standard and resistant strains of M. fortuitum were obtained from the microbial bank of the Department of Mycobacteriology and Pulmonary Research, Pasteur Institute of Iran. RESULTS: It was observed that nanofluid containing MWCNT-COOH can exert antimicrobial effects on M. fortuitum and significantly reduce bacterial resistance to antibiotics including kanamycin and streptomycin. In the presence of antibiotics and nanofluids containing MWCNT-COOH at a dose of 28.5 µg/mL, no growth was observed. CONCLUSION: One of the main antimicrobial mechanisms of MWCNT-COOH is penetration into the bacterial cell wall. In this study, by using the nanofluid containing MWCNT-COOH with increased stability, the antibiotic resistance of M. fortuitum was significantly reduced at lower dilutions compared to the antibiotic alone.


Assuntos
Anti-Infecciosos , Mycobacterium fortuitum , Nanotubos de Carbono , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Bactérias , Resistência Microbiana a Medicamentos , Nanotubos de Carbono/química
8.
BMC Microbiol ; 22(1): 261, 2022 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-36309645

RESUMO

PURPOSE: Nontuberculous mycobacteria (NTM) are ubiquitous bacteria that are naturally resistant to disinfectants and antibiotics and can colonize systems for supplying drinking water. Therefore, this study aimed to evaluate the prevalence of NTM in the drinking water of six hospitals in Tehran, Iran. METHODS: Totally, 198 water samples were collected. Each water sample was filtered via a membrane filter with a pore size of 0.45 µm and then decontaminated by 0.005% cetylpyridinium chloride. The membrane filters were incubated on two Lowenstein-Jensen media at 25 °C and 37 °C for 8 weeks. The positive cultures were identified with phenotypic tests, and then NTM species were detected according to the hsp65, rpoB, and 16S rDNA genes. Drug susceptibility testing (DST) was also carried out. RESULTS: Overall, 76 (40.4%) of the isolates were slowly growing mycobacteria (SGM) and 112 (59.6%) of the ones were rapidly growing mycobacteria (RGM). The most common NTM were Mycobacterium aurum, M. gordonae, M. phocaicum, M. mucogenicum, M. kansasii, M. simiae, M. gadium, M. lentiflavum, M. fortuitum, and M. porcinum. Among these 188 samples, NTM ranged from 1 to > 300 colony-forming unit (CFU) /500 mL, with a median of 182 CFU/500 mL. In the infectious department of all hospitals, the amount of CFU was higher than in other parts of the hospitals. The DST findings in this study indicated the diversity of resistance to different drugs. Among RGM, M. mucogenicum was the most susceptible isolate; however, M. fortuitum showed a different resistance pattern. Also, among SGM isolates, M. kansasii and M. simiae, the diversity of DST indicated. CONCLUSIONS: The current study showed NTM strains could be an important component of hospital water supplies and a possible source of nosocomial infections according to the CFU reported in this study. The obtained findings also help clarify the dynamics of NTM variety and distribution in the water systems of hospitals in the research area.


Assuntos
Água Potável , Infecções por Mycobacterium não Tuberculosas , Mycobacterium tuberculosis , Humanos , Micobactérias não Tuberculosas , Infecções por Mycobacterium não Tuberculosas/epidemiologia , Infecções por Mycobacterium não Tuberculosas/microbiologia , Testes de Sensibilidade Microbiana , Irã (Geográfico)/epidemiologia , RNA Ribossômico 16S/genética , Mycobacterium tuberculosis/genética , Hospitais
9.
J Med Virol ; 94(12): 6023-6027, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35927225

RESUMO

BK polyomavirus (BKPyV) is a well-known cause of nephropathy in renal transplant recipients. It has recently received much attention from researchers as a major predisposing factor for various cancers. This study aimed to investigate how BKPyV affected the advancement of papillary thyroid carcinoma (PTC). A total of 1057 samples were tested for BKPyV DNA and RNA, comprising 645 paraffin-embedded PTC biopsy samples (PEBS), 412 fresh biopsy samples (FBS), and 1057 adjacent noncancerous samples. The BKPyV DNA was found in 511 (48.3%) of the specimens, including 347 (84.2%) FBS and 164 (25.4%) PEBS. The mean BKPyV copy number was significantly lower in patients with PEBS (0.5 × 10-4 ± 0.1 × 10-4 copies/cell) than in FBS (1.3 × 10-1 ± 0.2 × 10-1 copies/cell) and non-PTC normal samples (0.3 × 10-5 ± 0.04 × 10-5 copies/cell). The PEBS had lower LT-Ag RNA expression than FBS, and no VP1 gene transcript expression was detected. In conclusion, although our findings indicated the presence of BKPyV in some Iranian PTC patients, more research is needed to corroborate these findings.


Assuntos
Vírus BK , Transplante de Rim , Infecções por Polyomavirus , Neoplasias da Glândula Tireoide , Infecções Tumorais por Vírus , Vírus BK/genética , Humanos , Irã (Geográfico)/epidemiologia , Transplante de Rim/efeitos adversos , RNA , Câncer Papilífero da Tireoide/complicações , Neoplasias da Glândula Tireoide/complicações , Neoplasias da Glândula Tireoide/epidemiologia , Transplantados , Infecções Tumorais por Vírus/complicações , Infecções Tumorais por Vírus/epidemiologia
10.
Microb Pathog ; 173(Pt A): 105798, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36174833

RESUMO

INTRODUCTION: Coronavirus disease-2019 (COVID-19) is a complex infection caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that can cause also gastrointestinal symptoms. There are various factors that determine the host susceptibility and severity of infection, including the renin-angiotensin system, the immune response, and the gut microbiota. In this regard, we aimed to investigate the gene expression of ACE, AGTR1, ACE2, and TMPRSS2, which mediate SARS-CoV-2 pathogenesis by Akkermansia muciniphila, Faecalibacterium prausnitzii, Bacteroides thetaiotaomicron, and Bacteroides fragilis on Caco-2 cells. Also, the enrichment analysis considering the studied genes was analyzed on raw data from the microarray analysis of COVID-19 patients. MATERIALS AND METHODS: Caco-2 cells were treated with live, heat-inactivated form and cell free supernatants of A. muciniphila, F. prausnitzii, B. thetaiotaomicron and B. fragilis for overnight. After RNA extraction and cDNA synthesis, the expression of studied genes was assessed by RT-qPCR. DNA methylation of studied genes was analyzed by Partek® Genomics Suite® software on the GSE174818 dataset. We used GSE164805 and GSE166552 datasets from COVID-19 patients to perform enrichment analysis by considering the mentioned genes via GEO2R, DAVID. Finally, the related microRNAs to GO terms concerned on the studied genes were identified by miRPath. RESULTS: The downregulation of ACE, AGTR1, and ACE2 genes by A. muciniphila, F. prausnitzii, B. thetaiotaomicron, and B. fragilis in live, heat-inactivated, and cell-free supernatants was reported for the first time. These genes had hypomethylated DNA status in COVID-19 patients' raw data. The highest fold enrichment in upregulated RAS pathways and immune responses belonged to ACE, AGTR1, and ACE2 by considering the protein-protein interaction network. The common miRNAs targeting the studied genes were reported as miR-124-3p and miR-26b-5p. CONCLUSION: In combination with our experimental data and bioinformatic analysis, we showed the potential of A. muciniphila, F. prausnitzii, B. thetaiotaomicron, and B. fragilis and their postbiotics to reduce ACE, ATR1, and ACE2 expression, which are essential genes that drive upregulated biological processes in COVID-19 patients. Accordingly, due to the potential of studied bacteria on the alteration of ACE, AGTR1, ACE2 genes expression, understanding their correlation with demonstrated miRNAs expression could be valuable. These findings suggest the importance of considering targeted gut microbiota intervention when designing the possible therapeutic strategy for controlling the COVID-19.


Assuntos
Enzima de Conversão de Angiotensina 2 , COVID-19 , Microbioma Gastrointestinal , MicroRNAs , Peptidil Dipeptidase A , Receptor Tipo 1 de Angiotensina , Humanos , Enzima de Conversão de Angiotensina 2/genética , Células CACO-2 , COVID-19/genética , Regulação para Baixo , Microbioma Gastrointestinal/genética , MicroRNAs/genética , Receptor Tipo 1 de Angiotensina/genética , SARS-CoV-2 , Peptidil Dipeptidase A/genética
11.
Virol J ; 19(1): 153, 2022 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-36163265

RESUMO

BACKGROUND: JC polyomavirus (JCPyV) is known to induce solid tumors such as astrocytomas, glioblastomas, and neuroblastomas in experimental animals, and recent studies have shown that the virus may be correlated with carcinogenesis. This study aimed to evaluate the impact of JCPyV on the progression of papillary thyroid cancer (PTC). METHODS: A total of 1057 samples, including 645 paraffin-embedded PTC biopsy samples (PEBS) and 412 fresh biopsy samples (FBS), and 1057 adjacent non-cancerous samples were evaluated for the presence of JCPyV DNA and RNA. RESULTS: We observed that 10.8% (114/1057) samples, including 17.5% (72/412) FBS and 6.5% (42/645) PEBS were positive for the JCPyV DNA. Among the JCPyV-positive samples, the mean JCPyV copy number was lower in patients with PEBS (0.3 × 10-4 ± 0.1 × 10-4 copies/cell) compared to FBS (1.8 × 10-1 ± 0.4 × 10-1 copies/cell) and non-PTC normal samples (0.2 × 10-5 ± 0.01 × 10-5 copies/cell), with a statistically significant difference (P < 0.001). The LT-Ag RNA expression was lower in PEBS than in FBS, while no VP1 gene transcript expression was found. CONCLUSIONS: Although our results confirmed the presence of JCPyV in some Iranian patients with PTC, more research is needed to verify these results.


Assuntos
Vírus JC , Infecções por Polyomavirus , Neoplasias da Glândula Tireoide , Humanos , Irã (Geográfico) , Vírus JC/genética , RNA , Câncer Papilífero da Tireoide
12.
Gerontology ; 68(11): 1201-1213, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35263739

RESUMO

BACKGROUND: Symptoms of cognitive impairments vary from mild without clinical manifestation to severe with advanced signs of dementia or Alzheimer's disease (AD). Growing evidence in recent years has indicated the association between the brain and gut microbiota, which has been described as the "gut-brain axis." This systematic review seeks to summarize the primary results from recent human and animal studies regarding the alteration of gut microbiota composition in cognitive disorders. METHODS: A systematic literature search was conducted on PubMed, Scopus, and Web of Science databases up to August 2020. The full texts of the papers were analyzed to retrieve the relevant information. RESULTS: Totally, 24 observational studies (14 animal and 13 human studies) were included. Most of the animal studies were performed on mouse models of AD. Human studies were conducted on patients with Parkinson's disease (3 studies), AD (4 studies), poststroke cognitive impairment patients (1 study), and patients with mild to severe cognitive impairment without mention to the cause of disease (5 studies). More recent evidence suggests that throughout aging Firmicutes and Bifidobacteria decrease but Proteobacteria increases. CONCLUSIONS: The gut microbiota may alter brain function or trigger various psychiatric conditions through the gut-brain axis. Prospective studies are needed in order to explore the role of the gut microbiota in the etiology of dementia and to achieve clinical recommendations.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Microbioma Gastrointestinal , Humanos , Animais , Camundongos , Disfunção Cognitiva/etiologia , Doença de Alzheimer/diagnóstico , Encéfalo , Envelhecimento
13.
Artigo em Inglês | MEDLINE | ID: mdl-35397157

RESUMO

Gut microbiota can interact with the immune system through direct or indirect pathways. In the indirect pathway, gut microbiota produces metabolites such as short chain fatty acids (SCFAs), which may modulate the immune response. SCFAs reduce inflammation, repair intestinal barrier, and induce propagation of specific immune cells, e.g., T regulatory cells (Treg), which can suppress reactive cells such as macrophage and dendritic cells (DCs). As one of the most dominant members of microbiota, Clostridium produces SCFAs. As one of SCFA members, butyrate plays an important role in the modulation of immune cells. Through butyrate production, Clostridium helps to generate aryl hydrocarbon receptor (AhR). AhR interacts with many proteins inside the cytoplasm including Heat Shock Protein 90 (HSP 90), HSP 23, and chaperone. Activation of AhR leads to its translocation inside the nucleus and gene expression, which yields cell differentiation, energy metabolism, microbial defense, and immune cell propagation. Moreover, it may interact with other cells like B-cell and epithelial cell, which are responsible for modulation and maturation, respectively. AhR causes upregulation in the co-stimulatory marker in the DCs and interacts with nuclear factor KB (NF-ĸB) to modulate cell function. Butyrate induces Treg (iTreg) propagation and upregulates the Forkhead box p3 (FOXP3) as a special marker of Treg cell. It may also yield signaling through G-protein coupled receptors (GPRs) which, in turn, facilitates polymorphonuclear (PMN) chemotaxis.The interaction between microbiota and non-immune cells, such as Paneth cells, leads to the secretion of antimicrobial substance, erection of barriers against bacterial pathogens, and regulation of microbiota composition via feedback effect. In addition, the components released from microbiota, such as peptidoglycan, reinforce the maturation of both the immune system and non-immune tissue development. Moreover, microbiota can directly activate the effector cells, e.g., macrophage, to secrete cytokines and propagate Treg cells.

14.
BMC Bioinformatics ; 22(1): 154, 2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33765916

RESUMO

BACKGROUND: A growing body of evidence has shown the association between tuberculosis (TB) infection and lung cancer. However, the possible effect of strain-specific behavior of Mycobacterium tuberculosis (M.tb) population, the etiological agent of TB infection in this association has been neglected. In this context, this study was conducted to investigate this association with consideration of the genetic background of strains in the M.tb population. RESULTS: We employed the elastic net penalized logistic regression model, as a statistical-learning algorithm for gene selection, to evaluate this association in 129 genes involved in TLRs and NF-κB signaling pathways in response to two different M.tb sub-lineage strains (L3-CAS1and L 4.5). Of the 129 genes, 21 were found to be associated with the two studied M.tb sub-lineages. In addition, MAPK8IP3 gene was identified as a novel gene, which has not been reported in previous lung cancer studies and may have the potential to be recognized as a novel biomarker in lung cancer investigation. CONCLUSIONS: This preliminary study provides new insights into the mechanistic association between TB infection and lung cancer. Further mechanistic investigations of this association with a large number of M.tb strains, encompassing the other main M.tb lineages and using the whole transcriptome of the host cell are inevitable.


Assuntos
Neoplasias Pulmonares , Mycobacterium tuberculosis , Tuberculose , Células A549 , Humanos , Neoplasias Pulmonares/genética , Mycobacterium tuberculosis/genética , Transdução de Sinais
15.
Virol J ; 18(1): 221, 2021 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-34775984

RESUMO

BACKGROUND: The recent pandemic caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has elevated several clinical and scientific questions. These include how host genetic factors influence the pathogenesis and disease susceptibility. Therefore, the aim of this study was to evaluate the impact of interferon lambda 3 and 4 (IFNL3/4) gene polymorphisms and clinical parameters on the resistance and susceptibility to coronavirus disease 2019 (COVID-19) infection. METHODS: A total of 750 SARS-CoV-2 positive patients (375 survivors and 375 nonsurvivors) were included in this study. All single-nucleotide polymorphisms (SNPs) on IFNL3 (rs12979860, rs8099917, and rs12980275) and IFNL4 rs368234815 were genotyped by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. RESULTS: In this study, a higher viral load (low PCR Ct value) was shown in nonsurvivor patients. In survivor patients, the frequency of the favorable genotypes of IFNL3/4 SNPs (rs12979860 CC, rs12980275 AA, rs8099917 TT, and rs368234815 TT/TT) was significantly higher than in nonsurvivor patients. Multivariate logistic regression analysis has shown that a higher low-density lipoprotein (LDL), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and PCR Ct value, and lower 25-hydroxyvitamin D, and also IFNL3 rs12979860 TT, IFNL3 rs8099917 GG, IFNL3 rs12980275 GG, and IFNL4 rs368234815 ∆G/∆G genotypes were associated with the severity of COVID-19 infection. CONCLUSIONS: The results of this study proved that the severity of COVID-19 infection was associated with clinical parameters and unfavorable genotypes of IFNL3/IFNL4 SNPs. Further studies in different parts of the world are needed to show the relationship between severity of COVID-19 infection and host genetic factors.


Assuntos
COVID-19/diagnóstico , Interferons/genética , Interleucinas/genética , SARS-CoV-2/isolamento & purificação , Adulto , Idoso , Antivirais/uso terapêutico , COVID-19/epidemiologia , Suscetibilidade a Doenças , Feminino , Genótipo , Humanos , Irã (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Polimorfismo de Fragmento de Restrição , Polimorfismo de Nucleotídeo Único , SARS-CoV-2/genética , Índice de Gravidade de Doença
16.
Microb Cell Fact ; 20(1): 219, 2021 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-34863163

RESUMO

BACKGROUND: Several studies have shown that probiotics have beneficial effects on weight control and metabolic health. In addition to probiotics, recent studies have investigated the effects of paraprobiotics and postbiotics. Therefore, we evaluated the preventive effects of live and pasteurized Akkermansia muciniphila MucT (A. muciniphila) and its extracellular vesicles (EVs) on HFD-induced obesity. RESULTS: The results showed that body weight, metabolic tissues weight, food consumption, and plasma metabolic parameters were increased in the HFD group, whereas A. muciniphila preventive treatments inhibited these HFD. The effects of pasteurized A. muciniphila and its extracellular vesicles were more noticeable than its active form. The HFD led to an increase in the colonic, adipose tissue, and liver inflammations and increased the expression of genes involved in lipid metabolism and homeostasis. Nevertheless, these effects were inhibited in mice that were administered A. muciniphila and its EVs. The assessment of the gut microbiota revealed significant differences in the microbiota composition after feeding with HFD. However, all treatments restored the alterations in some bacterial genera and closely resemble the control group. Also, the correlation analysis indicated that some gut microbiota might be associated with obesity-related indices. CONCLUSIONS: Pasteurized A. muciniphila and its EVs, as paraprobiotic and postbiotic agents, were found to play a key role in the regulation of metabolic functions to prevent obesity, probably by affecting the gut-adipose-liver axis.


Assuntos
Tecido Adiposo/metabolismo , Vesículas Extracelulares , Obesidade/prevenção & controle , Probióticos/administração & dosagem , Akkermansia/citologia , Akkermansia/fisiologia , Animais , Homeostase/genética , Metabolismo dos Lipídeos/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pasteurização
17.
BMC Infect Dis ; 21(1): 2, 2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33397308

RESUMO

BACKGROUND: Acquiring comprehensive insight into the dynamics of Mycobacterium tuberculosis (Mtb) population structure is an essential step to adopt effective tuberculosis (TB) control strategies and improve therapeutic methods and vaccines. Accordingly, we performed this systematic review and meta-analysis to determine the overall prevalence of Mtb genotypes/ sublineages in Iran. METHODS: We carried out a comprehensive literature search using the international databases of MEDLINE and Scopus as well as Iranian databases. Articles published until April 2020 were selected based on the PRISMA flow diagram. The overall prevalence of the Mtb genotypes/sublineage in Iran was determined using the random effects or fixed effect model. The metafor R package and MedCalc software were employed for performing this meta-analysis. RESULTS: We identified 34 studies for inclusion in this study, containing 8329 clinical samples. Based on the pooled prevalence of the Mtb genotypes, NEW1 (21.94, 95% CI: 16.41-28.05%), CAS (19.21, 95% CI: 14.95-23.86%), EAI (12.95, 95% CI: 7.58-19.47%), and T (12.16, 95% CI: 9.18-15.50%) were characterized as the dominant circulating genotypes in Iran. West African (L 5/6), Cameroon, TUR and H37Rv were identified as genotypes with the lowest prevalence in Iran (< 2%). The highest pooled prevalence rates of multidrug-resistant strains were related to Beijing (2.52, 95% CI) and CAS (1.21, 95% CI). CONCLUSIONS: This systematic review showed that Mtb populations are genetically diverse in Iran, and further studies are needed to gain a better insight into the national diversity of Mtb populations and their drug resistance pattern.


Assuntos
Variação Genética , Genótipo , Mycobacterium tuberculosis/genética , Tuberculose Pulmonar/epidemiologia , Humanos , Irã (Geográfico)/epidemiologia , Prevalência , Tuberculose Pulmonar/microbiologia
18.
Mediators Inflamm ; 2021: 6611222, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33953641

RESUMO

Severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) is responsible for the outbreak of a new viral respiratory infection. It has been demonstrated that the microbiota has a crucial role in establishing immune responses against respiratory infections, which are controlled by a bidirectional cross-talk, known as the "gut-lung axis." The effects of microbiota on antiviral immune responses, including dendritic cell (DC) function and lymphocyte homing in the gut-lung axis, have been reported in the recent literature. Additionally, the gut microbiota composition affects (and is affected by) the expression of angiotensin-converting enzyme-2 (ACE2), which is the main receptor for SARS-CoV-2 and contributes to regulate inflammation. Several studies demonstrated an altered microbiota composition in patients infected with SARS-CoV-2, compared to healthy individuals. Furthermore, it has been shown that vaccine efficacy against viral respiratory infection is influenced by probiotics pretreatment. Therefore, the importance of the gut microbiota composition in the lung immune system and ACE2 expression could be valuable to provide optimal therapeutic approaches for SARS-CoV-2 and to preserve the symbiotic relationship of the microbiota with the host.


Assuntos
Microbioma Gastrointestinal/fisiologia , Microbiota/fisiologia , COVID-19/microbiologia , Humanos , Probióticos/uso terapêutico , SARS-CoV-2/patogenicidade
19.
Emerg Infect Dis ; 26(10): 2524-2526, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32946733

RESUMO

Primary ciliary dyskinesia is a rare autosomal recessive disorder that causes oto-sino-pulmonary disease. We report a case of pulmonary infection related to mimivirus in a 10-year-old boy with primary ciliary dyskinesia that was identified using molecular techniques. Our findings indicate that the lineage C of mimivirus may cause pneumonia in humans.


Assuntos
Transtornos da Motilidade Ciliar , Mimiviridae , Pneumonia , Criança , Humanos , Masculino
20.
Microb Pathog ; 144: 104200, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32289465

RESUMO

The human gut harbors diverse microbes that play a fundamental role in the well-being of their host. Microbiota disruption affects the immune function, metabolism, and causes several diseases. Therefore, understanding how the microbiome is adjusted, and identifying methods for manipulating it is critical. Studies have found that there is an inverse association between MicroRNAs (miRNAs) abundance and microbe abundance. miRNAs are known to be engaged in post-transcription regulation of cell-autonomous gene expression. Recently, they have gained great attention for their proposed roles in cell-to-cell communication, and as biomarkers for human disease. Here, we review recent studies on the role of miRNAs as a component of outer membrane vesicles (OMVs) in the composition of gut microbiota and their significance in the human situation of health and diseases and discuss their effect on inflammatory responses and dysbiosis. Further, we explain how probiotics exert influence on the expression of miRNAs.


Assuntos
Microbioma Gastrointestinal/fisiologia , MicroRNAs/metabolismo , Animais , Biomarcadores , Disbiose/imunologia , Microbioma Gastrointestinal/imunologia , Expressão Gênica , Interações entre Hospedeiro e Microrganismos/imunologia , Interações entre Hospedeiro e Microrganismos/fisiologia , Humanos , Probióticos
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