Pharmacogenetic Study of Drugs Affecting Mycobacterium tuberculosis.

BACKGROUND: Pharmacogenetic research has led to significant progress in understanding how genetic factors influence drug response in tuberculosis (TB) treatment. One ongoing challenge is the variable occurrence of adverse drug reactions in some TB patients. Previous studies have indicated that genetic variations in the N-acetyltransferase 2 (NAT2) and solute carrier organic anion transporter family member 1B1 (SLCO1B1) genes can impact the blood concentrations of the first-line anti-TB drugs isoniazid (INH) and rifampicin (RIF), respectively. This study aimed to investigate the influence of pharmacogenetic markers in the NAT2 and SLCO1B1 genes on TB treatment outcomes using whole-exome sequencing (WES) analysis. METHODS: DNA samples were collected from 30 healthy Iranian adults aged 18-40 years. The allelic frequencies of single-nucleotide polymorphisms (SNPs) in the NAT2 and SLCO1B1 genes were determined through WES. RESULTS: Seven frequent SNPs were identified in the NAT2 gene (rs1041983, rs1801280, rs1799929, rs1799930, rs1208, rs1799931, rs2552), along with 16 frequent SNPs in the SLCO1B1 gene (rs2306283, rs11045818, rs11045819, rs4149056, rs4149057, rs2291075, rs201722521, rs11045852, rs11045854, rs756393362, rs11045859, rs74064211, rs201556175, rs34671512, rs71581985, rs4149085). CONCLUSION: Genetic variations in NAT2 and SLCO1B1 can affect the metabolism of INH and RIF, respectively. A better understanding of the pharmacogenetic profile in the study population may facilitate the design of more personalized and effective TB treatment strategies. Further research is needed to directly correlate these genetic markers with clinical outcomes in TB patients.

The Role of Efflux Pumps transporter in Multi-drug Resistant Tuberculosis: Mycobacterial memberane protein(MmpL5).

BACKGROUND: The overexpression of efflux pumps (Eps) was reported to contribute to multidrug resistant tuberculosis (MDR-TB). Increases in Eps that expel structurally unrelated drugs contribute to reduced susceptibility by decreasing the intracellular concentration of antibiotics. In the present study, an association of mycobacterial membrane protein (MmpS5-MmpL5) Ep and its gene regulator (Rv0678) was investigated in MDR-tuberculosis isolates. METHODS: MTB strains were isolated from patients at two different intervals, i.e., once when they had persistent symptoms despite 3-15 ≥ months of treatment and once when they had started new combination therapy ≥2-3 months. Sputum specimens were subjected to Xpert MTB/rifampicin test and then further susceptibility testing using proportional method and multiplex polymerase chain reaction (PCR) were performed on them. The isolates were characterized using both 16S-23S RNA and hsp65 genes spacer (PCR-restriction fragment length polymorphism). Whole-genome sequencing (WGS) was investigated on two isolates from culture-positive specimen per patient. The protein structure was simulated using the SWISS-MODEL. The input format used for this web server was FASTA (amino acid sequence). Protein structure was also analysis using Ramachandran plot. RESULTS: WGS documented deletion, insertion, and substitution in transmembrane transport protein MmpL5 (Rv0676) of Eps. Majority of the studied isolates (n = 12; 92.3%) showed a unique deletion mutation at three positions: (a) from amino acid number 771 (isoleucine) to 776 (valine), (b) from amino acid number 785 (valine) to 793 (histidine), and (c) from amino acid number 798 (leucine) to 806 (glycine)." One isolate (7.6%) had no deletion mutation. In all isolates (n = 13; 100%), a large insertion mutation consisting of 94 amino acid was observed "from amino acid number 846 (isoleucine) to amino acid number 939 (leucine)". Thirty-eight substitutions in Rv0676 were detected, of which 92.3% were identical in the studied isolates. WGS of mycobacterial membrane proteins (MmpS5; Rv0677) and its gene regulator (Rv0678) documented no deletion, insertion, and substitution. No differences were observed between MmpS5-MmpL5 and its gene regulator in isolates that were collected at different intervals. CONCLUSIONS: Significant genetic mutation like insertion, deletion, and substitution within transmembrane transport protein MmpL5 (Rv0676) can change the functional balance of Eps and cause a reduction in drug susceptibility. This is the first report documenting a unique amino acid mutation (insertion and deletion ≥4-94) in Rv0676 among drug-resistant MTB. We suggest the changes in Mmpl5 (Rv0676) might occurred due to in-vivo sub-therapeutic drug stress within the host cell. Changes in MmpL5 are stable and detected through subsequent culture-positive specimens.

Identification of seven types of pili in Mycobacterium tuberculosis: Using atomic force microscopy.

Background: Pili are polymeric, hydrophobic, proteinaceous structures generally composed of a major repeating subunit called pilin and, in some cases, a minor tip-associated adhesin subunit. Pili are involved in many virulence-associated functions, such as biofilm formation, adherence, and colonization of mucosal surfaces. Methods: Mycobacterium tuberculosis (MTB) strains were isolated from clinically and laboratory-confirmed cases of tuberculosis (TB). The TB isolates were subjected to the Xpert MTB/rifampicin test and then, further susceptibility testing was performed on them against first- and second-line drugs using proportional methods. Thereafter, the selected isolates were subculture in Dubos Tween-albumin liquid culture medium, and at their exponential growth phase (OD600 = 0.05 (5 × 106 colony-forming unit/mL), cells were observed under atomic force microscopy (AFM). For each isolate, 15-20 steel sample packs were prepared and observed under AFM. Here, the data presented are the result of average observation. Results: Under AFM, seven different types of pili were detected, out of which four types, i.e., Type III, Type IV secretion pili, and Type IV-like pili, curli-like pili (MTP) were similar to reported pili in Gram-negative and Gram-positive bacteria. Whereas the other three forms, i.e., Type V (relief funnel pili), Type VI (adhesion tapering), and Type VII (adhesion flap pili), were newly identified and named according to their appearance. Both Types of IV pili were detected in all clinical isolates irrespective of their susceptibility patterns, although significant differences were observed from the side of their protruding. Type Curli pili is similar in appearance in all clinical isolates. Types VI and VII were detected only in extensively drug-resistant and totally drug-resistant-TB isolates (100%). The Type III pili (secretion needle pili) was present in both susceptible- and drug-resistant bacilli, although in drug-resistant strains, we found a considerable difference in their length (50 µ ±10 nm in length) and sometimes, they also had tapering at end. The Type V pili was seen in susceptible isolates but it was at the resting stage (100%; lying aside of cell wall) whereas in drug-resistant isolates, they were getting apart from the cell wall of bacilli with a clear tapering or funnel shape structure. Conclusion: The results of this study highlight the importance of new types of pili expressions in respect of susceptibility patterns in TB. The identified new types of pili would be promising approaches for the treatment and prevention of drug-resistant TB, which needs further investigation.

Non-coding RNAs/DNMT3B axis in human cancers: from pathogenesis to clinical significance.

Cancer is a complex disease with many contributing factors, and researchers have gained extensive knowledge that has helped them understand the diverse and varied nature of cancer. The altered patterns of DNA methylation found in numerous types of cancer imply that they may play a part in the disease's progression. The human cancer condition involves dysregulation of the DNA methyltransferase 3 beta (DNMT3B) gene, a prominent de novo DNA methyltransferase, and its abnormal behavior serves as an indicator for tumor prognosis and staging. The expression of non-coding RNAs (ncRNAs), which include microRNAs (miRNA), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), is critical in controlling targeted gene expression and protein translation and their dysregulation correlates with the onset of tumors. NcRNAs dysregulation of is a critical factor that influences the modulation of several cellular characteristics in cancerous cells. These characteristics include but are not limited to, drug responsiveness, angiogenesis, metastasis, apoptosis, proliferation, and properties of tumor stem cell. The reciprocal regulation of ncRNAs and DNMT3B can act in synergy to influence the destiny of tumor cells. Thus, a critical avenue for advancing cancer prevention and treatment is an inquiry into the interplay between DNMT3B and ncRNAs. In this review, we present a comprehensive overview of the ncRNAs/DNMT3B axis in cancer pathogenesis. This brings about valuable insights into the intricate mechanisms of tumorigenesis and provides a foundation for developing effective therapeutic interventions.

The impact of particulate matters on apoptosis in various organs: Mechanistic and therapeutic perspectives.

Ecological air contamination is the non-homogenous suspension of insoluble particles into gas or/and liquid fluids known as particulate matter (PM). It has been discovered that exposure to PM can cause serious cellular defects, followed by tissue damage known as cellular stress. Apoptosis is a homeostatic and regulated phenomenon associated with distinguished physiological actions inclusive of organ and tissue generation, aging, and development. Moreover, it has been proposed that the deregulation of apoptotic performs an active role in the occurrence of many disorders, such as autoimmune disease, neurodegenerative, and malignant, in the human population. Recent studies have shown that PMs mainly modulate multiple signaling pathways involved in apoptosis, including MAPK, PI3K/Akt, JAK/STAT, NFκB, Endoplasmic Stress, and ATM/P53, leading to apoptosis dysregulation and apoptosis-related pathological conditions. Here, the recently published data concerning the effect of PM on the apoptosis of various organs, with a particular focus on the importance of apoptosis as a component in PM-induced toxicity and human disease development, is carefully discussed. Moreover, the review also highlighted the various therapeutic approaches, including small molecules, miRNA replacement therapy, vitamins, and PDRN, for treating diseases caused by PM toxicity. Notably, researchers have considered medicinal herbs a potential treatment for PM-induced toxicity due to their fewer side effects. So, in the final section, we analyzed the performance of some natural products for inhibition and intervention of apoptosis arising from PM-induced toxicity.

MiR-211 plays a dual role in cancer development: From tumor suppressor to tumor enhancer.

Cancer is a general term for more than 100 unique malignancies in different organs of the body. Each cancer type and subtype has its own unique genetic, epigenetic, and cellular factors accountable for malignant progression and metastasis. Small non-coding RNAs called miRNAs target mRNAs and play a vital part in the pathogenesis of human diseases, specifically cancer. Recent investigations provided knowledge of the deregulation of miR-211 in various cancer types and disclosed that miR-211 has an oncogenic or tumor-suppressive impact on tumourigenesis and cancer development. Moreover, recent discoveries which clarify the essential functions of miR-211 might provide proof for its prognosis, diagnostic and therapeutic impact on cancer. Thereby, this review will discuss recent findings regarding miR-211 expression level, target genes, and mechanisms in different cancers. In addition, the most recent results that propose miR-211 usefulness as a noninvasive biomarker and therapeutic factor for the diagnosis and treatment of cancer will be explained.

Effect of COVID-19 pandemic on incidence of mycobacterial diseases among suspected tuberculosis pulmonary patients in Tehran, Iran.

Background: Recent pandemic of coronavirus SARS-CoV-2 (COVID-19) caused limitations in the country's strategies to fight against mycobacterial infections. The aim of this study was to compare the suspected tuberculosis (TB) pulmonary patients before and during the COVID-19 pandemic (January 2018-December 2021) who were referred to the National Reference TB Laboratory (NRL TB), Tehran, Iran. The mycobacterial isolated strains were identified and compared with previous data. Methods: A total of 16,899 clinical samples collected from 7041 suspected pulmonary TB patients were received from 2018 to 2021. Primary isolation of Mycobacterium isolates was done on Löwenstein-Jensen medium. Then, the DNA was extracted from acid-fast bacillus culture-positive samples and identification was performed by IS6110, Hsp65, and 16S-23S rRNA genes using polymerase chain reaction (PCR), PCR-restriction fragment length polymorphism, and nested PCR methods. Results: A total of 11679 specimens (69.1%) from 4866 suspected TB patients were collected in 2018-2019 and 5220 specimens (30.8%; from 2175 patients) in 2020-2021. Out of 11679 specimens, 2046 samples that belong to 852 patients were infected with Mycobacterium tuberculosis, and the remaining were non-TB Mycobacterium (NTM) species (n = 244) isolated from 102 patients. The cultures for 12894 specimens were either negative (76.3%) or contaminated (845/16899; 5%). A comparison of the total number of patients who were referred for diagnosis and treatment (954/666 patients, P > 0.05) showed a 30.1% reduction during the COVID-19 pandemic. Although, with these low number of patients, the significant increases of NTM species (P < 0.05) among suspected TB pulmonary patients were observed. Besides, new species of NTM, for example, Mycobacterium peregrinum and Mycobacterium montefiorense, were detected. For the past 20 years, these two species were not reported from pulmonary patients in Iran. Conclusions: During the pandemic of COVID-19, the TB diagnosis network became irregular, as a consequence, many patients could not reach the treatment center, and this could increase the circulation of mycobacterial diseases (TB and NTM). The study shows the emergence of new opportunistic NTM species also.

Correlation of single-nucleotide polymorphism at interferon-gamma R1 (at Position - 56) in positive purified protein derivative health workers with COVID-19 infection.

Background: The aim of the present study was to investigate the susceptibility of purified protein derivative (PPD) plus health-care workers to SARS-CoV-2 (COVID-19). For this reason, single-nucleotide polymorphism (SNP) of interferon-gamma (IFN-γ) gene at position +2109 and IFN-γ receptor 1 (R1) at position -56 was assessed in PPD plus group before and after COVID-19 infection (2017-2018; 2020-2021). Methods: The selected study cases (n = 100) that were working in tuberculosis (TB) unite (5-10 years) with PPD positivity >15 mm (16-20 mm) were included in this investigation. Sampling was done twice, once before and after the COVID-19 pandemic. Group A contains 50 samples collected from the GenBank TB laboratory that belong to TB staff before the pandemic (2017-2018). The other sample (Group B; 2021) was collected from the same unite during the COVID-19 pandemic. The SNP in the IFN-γ gene (+2109; 670 bp) and IFN-γ R 1 (-56; 366 bp) was performed using a specific primer and the polymerase chain reaction products were digested using restriction enzyme Fau I and Bts I, respectively. Statistical analyses were used to obtain the frequency of alleles among all studied cases. The confidence intervals (CIs) and t-test were calculated using the SPSS and GraphPad Prism software. Results: In overall, the most frequent genotype in Group A was AA (41/50; 82%) and Group B was 76% (38/50) in position + 2109 (odds ratio [OR] = 0.69, 95% CI, 0.26-1.83, and P = 0.46). Although in position -56, the most frequent genotype in Group A was TT (35/50; 70%) which significantly was than Group B TT (15/50; 30%) (OR = 0.184, 95% CI, 0.78-0.43, and P = 0.00). The frequency of allele A was more in both groups at position + 2109 (OR = 0.815, 95% CI, 0.23-2.86, and P = 0.75), whereas the dominate allele at position -56 was T in Group A (OR = 1.37, 95% CI, 0.62-3.02, and P = 0.42). Conclusion: No significant differences were observed in + 2109 in genotype among Group A and B. The main differences were seen in IFN-γ R1 at position (-56) between Group A and B. Hence, the IFN-γ R1 may play important role in COVID-19 infection. However, more study is needed to clear the IFN-γ correlation to COVID-19 infection.

Molecular Dynamic Simulations and Molecular Docking as a Potential Way for Designed New Inhibitor Drug without Resistance.

Mycobacterium tuberculosis is the cause of tuberculosis in humans and is responsible for more than 2 million deaths per year. Despite the development of anti-tuberculosis drugs (Isoniazid, Rifampicin, Ethambutol, pyrazinamide, streptomycin, etc.) and the TB vaccine, this disease has claimed the lives of many people around the world. Drug resistance in this disease is increasing day by day. Conventional methods for discovering and developing drugs are usually time-consuming and expensive. Therefore, a better method is needed to identify, design, and manufacture TB drugs without drug resistance. Bioinformatics applications in obtaining new drugs at the structural level include studies of the mechanism of drug resistance, detection of drug interactions, and prediction of mutant protein structure. In the present study, computer-based approaches including molecular dynamics simulation and molecular docking as a novel and efficient method for the identification and investigation of new cases as well as the investigation of mutated proteins and compounds will be examined .

Non-coding RNA in SARS-CoV-2: Progress toward therapeutic significance.

The recently developed pathogenic virus, SARS-CoV-2, was found in the Hubei Province, China. Giving rise to a broad spectrum of symptoms, SARS-CoV-2 rapidly spread across the globe, causing multi-systemic and dangerous complications, with death in extreme cases. Thereby, the number of research cases increases every day on preventing infection and treating its resulting damage. Accumulating evidence suggests noncoding RNAs (ncRNAs) are necessary for modifying virus infection and antiviral immune reaction, along with biological processes regulating SARS-CoV-2 and subsequent disease states. Therefore, understanding these mechanisms might provide a further understanding of the pathogenesis and feasible therapy alternatives against SARS-CoV2. Consequently, the molecular biology of SARS-CoV-2, ncRNA's role in its infection, and various RNA therapy tactics against the virus have been presented in this review section.

The role of interferon-gamma and interferon-gamma receptor in tuberculosis and nontuberculous mycobacterial infections.

Mycobacterium tuberculosis (Mtb) and nontuberculous mycobacteria (NTM) remain the leading causes of lung disease and mortality worldwide. Interferon-gamma (IFN-γ) and its receptor (IFN-γR) play a key role in mediating immunity against Mtb and NTM. This study was conducted as a systematic review; all information was collected from databases such as: PubMed, Scopus, Medline, SID, and medical databases. Finally, all the collected data were reviewed, and all content was categorized briefly. There is growing evidence that IFN-γ plays an important role in host defense against these two intracellular pathogens by activating macrophages. In addition, IFN-γ has been shown to be an integral part of various antibacterial methods such as granuloma formation and phagosome-lysosome fusion, both of which lead to the death of intracellular Mycobacterium. As a result, its absence is associated with overgrowth of intracellular pathogens and disease caused by Mtb or Mycobacterium nontuberculosis. We also look at the role of IFN-γR in Mtb or NTM because IFN-γ acts through IFN-γR. Finally, we introduce new approaches to the treatment of M. tuberculosis complex (MTC) and NTM disease, such as cell and gene-based therapies that work by modulating IFN-γ and IFN-γR.

Efficient process development for high-level production, purification, formulation, and characterization of recombinant mecasermin in Escherichia coli.

Overproduction of recombinant mecasermin was achieved by investigation of effect of three factors, temperature, inducer amount, and culture media, at three levels according to the Taguchi statistical design in Escherichia coli in a bench-scale bioreactor. In optimal conditions (induction temperature 28 °C, terrific broth with glucose (TB+G) medium, with 0.1 mM IPTG as inducer) 0.84 g/L mecasermin with expression levels of 38% of total protein and 4.13 g/L final dry cell biomass was produced, that is one of the highest values of recombinant protein has been reported in the batch system. The cell disruption was done by lysozyme pretreatment with sonication to the efficient purification of mecasermin. The isolated and washed inclusion bodies were solubilized in Gdn-HCl at pH 5.4 and folded with glutathione and purified with gel filtration. The purified rhIGF-1 (mecasermin) was formulated with arginine. Mecasermin protein remained t stable at 4 °C for up to 2 years. The quantitative and qualitative control indicated that mecasermin is expressed correctly (without the initial methionine by mass spectrometry), pure (without endotoxin and other protein impurities), correct folding (FTIR, RF-HPLC), monomer form (SEC-HPLC), and active (bioactivity test). Also, the purification results revealed that expression at low temperature results in the efficient purification of the overproduced mecasermin with high quantity and quality.

Human genetic background in susceptibility to tuberculosis.

Tuberculosis (TB), especially in developing countries, is a major threat to human health. The pathogenesis of TB remains poorly understood, and <5%-10% of individuals infected with Mycobacterium tuberculosis (MTB) will develop clinical disease. The human genetic factors contributing to susceptibility or resistance to TB pathogenesis have been investigated by high-throughput and low-throughput association studies. Genetic polymorphisms of several genes including TLR, IGRM, VDR, ASAP1, AGMO, FOXP1, and UBLCP1 effect on the disease phenotype and also the outcome of TB treatment. Recently, microRNAs (miRNAs), which negatively regulated gene expression at the posttranscriptionally level, have gained increasing attention due to their altered expression in various human diseases, including some infections. They are crucial posttranscriptional regulators of immune response in both innate and adaptive immunity. It has been established in recent studies that the host immune response against MTB is regulated by many miRNAs, most of which are induced by MTB infection. Moreover, differential expression of miRNAs in TB patients may help distinguish between TB patients and healthy individuals or latent TB. In this review, we summarize and discuss the literature and highlight the role of selected single nucleotide polymorphisms and miRNAs that have been associated with TB infection.

Prevalence of Mycobacterium abscessus among the Patients with Nontuberculous Mycobacteria.

BACKGROUND: Considering the importance of the increasing incidence of non-tuberculous mycobacteria, especially Mycobacterium abscessus worldwide, we conducted a study to evaluate the incidence of these diseases in our area. The aim of this study was to evaluate the prevalence of M. abscessus in patients with non-tuberculous mycobacteria. METHODS: This descriptive study was performed on 18,083 samples isolated from patients with non-tuberculous mycobacteria during 2011-2017 at the Mycobacteriology Research Center (MRC), Tehran, Iran. To identify the Mycobacterium species, a 439 bp fragment of the IS6110 gene was first amplified using primers TB1 and TB2. Samples with a negative polymerase chain reaction (PCR) result were analyzed to investigate non-tuberculosis mycobacteria (NTM), especially M. abscessus using the RFLP method. RESULTS: Of the 18,083 samples, 5513 (30.49%, 95% CI, 12.95) strains of Complex Tuberculosis and 236 (1.31%, 95% CI, 1.84) strains of NTM were identified. The mean age of the patients with NTM was 18 years, and most of them were male. The most commonly identified species in this study were M. abscessus type Ι 32 (13.56%, 95% CI, 18.36) and M. abscessus type II 13 (5.51%, 95%CI, 20.04). CONCLUSION: In this study, we observed a high prevalence of Mycobacterium abscessus type 1 in patients. As the treatment protocol for non-TB mycobacteria is different from M. abscessus complex, the diagnosis of these species as soon as possible will be significant for physicians.

Association of IL-10 gene promoter polymorphisms with susceptibility to pseudoexfoliation syndrome, pseudoexfoliative and primary open-angle glaucoma.

BACKGROUND: The involvement of cytokines in pathogenesis of pseudoexfoliation syndrome and glaucoma has been demonstrated in several studies. The aim of the present study was to explore the association between three promoter polymorphisms -592C/A (rs1800872), - 819C/T (rs1800871) and -1082A/G (rs1800896) of interleukin 10 (IL-10) gene with susceptibility to pseudoexfoliation syndrome (PEX), pseudoexfoliative glaucoma (PEXG), and primary open-angle glaucoma (POAG). METHODS: In this study, 114 PEX, 118 PEXG, 114 POAG patients and 126 healthy individuals from Iranian population were participated. Detailed ophthalmic examinations by an ophthalmologist including slit-lamp bio-microscopic examination, dilated examination of the lens, gonioscopy, and funduscopy were carried out on patients and controls. Genomic DNA was extracted from the blood samples and ARMS-PCR was performed to detect promoter polymorphisms of IL-10. RESULTS: In all three SNPs studied, there was a significant difference in the genotype distribution between patients and control subjects. Results revealed that the AA genotype of IL-10 -592C/A SNP is associated with PEX. However, TT genotype of -819C/T and AA genotype of -1082A/G SNP are significantly associated with susceptibility to either PEX or PEXG and POAG disorders. Furthermore, the ACC haplotype containing the IL-10 -1082A allele was associated with PEX (P = 0.02, OR = 5.76, 95% CI = 5.17-24.49), PEXG (P = 0.006, OR = 7.54, 95% CI = 6.62-30.76) and POAG (P = 0.003, OR = 8.11, 95% CI = 7.13-33.15). CONCLUSIONS: Our results demonstrated that IL-10 gene promoter polymorphisms are associated with susceptibility to PEX, PEXG and POAG in Iranian population. Considering the fact that IL-10 polymorphisms are associated with various IL-10 expressions, further research is needed to explain its involvement in these disorders and the formation of extracellular fibrillar amyloid deposits in PEX and PEXG.

TNFα -857 C/T and TNFR2 +587 T/G polymorphisms are associated with cystic fibrosis in Iranian patients.

Identification of modifier genes influencing phenotype of cystic fibrosis (CF) patients has become a challenge in CF pathophysiology, prognostic estimations and development of new therapeutic strategies. The aim of this study was to explore the association between four genetic polymorphisms of three modifier genes with CF, by comparing their alleles, genotypes and haplotype frequencies in patients and controls. In this favor, two regulatory polymorphic loci in TNFα promoter (-857C/T, rs1799724 and -238A/G, rs361525) and two functional polymorphic loci in TNFR1 (+36A/G, rs767455) and TNFR2 (+587T/G, rs1061622) were genotyped in 70 patients and 79 controls, using PCR-RFLP. Clinical pulmonary data were also recorded from all studied patients. Results indicated that an association was observed between both T allele and CT/TT genotypes of TNFα (P = 0.0005, OR = 7.06, 95% CI = 3.71-13.45) with CF under dominant model of inheritance. GG genotype of TNFR2 +587 (P = 0.0005, OR = 4.92, 95%CI = 2.34-10.34) was significantly associated with CF using recessive model. Consistently, more severe pulmonary disorder was found for patients carrying either T dominant allele of TNFα -857 or GG genotype of TNFR2 +587 polymorphic sites. Despite an association of A-T and G-T haplotypes with CF, no significant association was found between these haplotypes and clinical parameters of CF. Overall, TNFα -857 T allele and GG genotype of TNFR2 +587 were more frequent in CF patients compared to healthy controls and hence, they showed an association with CF and severe pulmonary phenotype in Iranian patients.

Association of Interferon-γ Receptor-1 Gene Polymorphism with Nontuberculous Mycobacterial Lung Infection among Iranian Patients with Pulmonary Disease.

Nontuberculous mycobacteria (NTM) cause significant pulmonary infections in humans. Researchers have reported an association between interferon-gamma receptor-1 (IFN-γR1 or IFNGR1) deficiency and susceptibility to NTM, but the relevance of polymorphism within these genes is not yet clear. In this study, a single nucleotide polymorphism (SNP), T to C, at position-56 in NTM patients with pulmonary disease was investigated. Molecular identification of Mycobacterium isolates was performed with hsp65 genes using polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP). Then, the host genomic DNA from confirmed NTM patients (N = 80) and control subjects (N = 80) were screened for SNPs of IFNGR1 (T-56C) by PCR-RFLP. The results indicated that NTM patients had higher TC (26/80; 32.5%) or CC (46/80; 57.5%) genotypes in comparison with control groups (TC genotypes [22/80, 27.5%]; CC genotypes [6/80, 7.5%]) (P < 0.05). In this regard, all the patients infected with rapid-growing Mycobacterium (RGM, i.e., Mycobacterium chelonae and Mycobacterium fortuitum) had CC genotypes (100%). In contrary, only 50.7% (35/69) of infected patients with slow-growing Mycobacterium (i.e., Mycobacterium simiae, Mycobacterium kansasii, and Mycobacterium avium-intracellulare) had CC genotypes. Thus, patients with CC mutation in IFNGR1 at position-56 are more likely to develop RGM infection. In overall, there is a significant association between SNP of IFNGR1 at position-56 and susceptibility to NTM infection. Based on these data, we propose SNP of IFNGR1 at position-56 as a suitable "biomarker" for identifying populations at higher risk of infection.

Modified rifampin nanoparticles: Increased solubility with slow release Rate.

BACKGROUND: Recent advances in nanotechnology-based drug delivery system have been shown to improve either antibacterial efficacy or pharmacokinetics behavior.The aim of this study was to design a rifampin nanoparticle (RIF-NP) which has a high loading capacity with the slow release profile. MATERIAL AND METHODS: The designed chitosan/gelatin/lecithin (Chg/L) RIF-NPs were prepared by multilamellar vesicle. Thereafter, the particle size, zeta potential, morphology, and release rate were investigated. To optimize the loading capacity and release profiles, different concentrations of lecithin were used. RESULTS: Our results showed a correlation of lecithin concentration with size, zeta potential, and loading capacity of RIF-NPs. Increases in lecithin concentration (0.2-2.0 g) could cause a significant size reduction in NPs (250-150 nm); the amount of zeta potential (from 14 to 49 mV;P < 0.05) and loading capacity increases from 8% to 20% (P < 0.05). Designed NPs had slow drug release profile which was influenced by pH and lecithin concentration. The cumulative percentage of RIF released at pH 7.4 was approximately 93% up to 12 h. In overall, release profile was better than standard drug, even in various pH conditions (pH = 1, 3.4, and 7.4). The Chg/L-RIF NPs may be considered as a promising drug nanocarrier. CONCLUSIONS: These NPs release RIF in slow and constant rate, which effectively might eliminate the bacilli and prevent the formation of RIF-resistant bacilli.

Effect of Heart Valve Decellularization on Xenograft Rejection.

OBJECTIVES: Endothelial cells harbor many antigenic determinants that may be targets for the immune system. The aim of this study was to determine the immunologic effects of decellularization, using 3 different methods, on xenograft rejection. MATERIALS AND METHODS: In a sterile plate containing phosphate-buffered saline, fresh sheep aortic heart valves were decellularized using 3 different enzymatic methods: with 900 µg/mL of collagenase at 40°C (method A), with 450 µg/mL of collagenase at 4°C (method B), and with 900 µg/mL of collagenase at 4°C (method C). Intact and decellularized valves were implanted subdermally into inbred male albino rabbits and extracted after 21 days (extra valve pieces were also extracted after 60 days, as control samples, for assessing chronic rejection). Valves were histologically analyzed for inflammatory cell infiltration. Subendothelial structure integrity was determined using surface electron microscope. RESULTS: No inflammatory cell infiltration was seen around the decellularized valve with method A, and no subendothelial structure change was observed by surface electron microscope. Infiltration of immune cells involved in rejection was not seen around valves decellularized with method B, although the subendothelial structure was relatively preserved and valve stiffness was increased. With method C, we observed a foreign body-type reaction around the intact valve and the decellularized valve. CONCLUSIONS: Method A is considered the optimal method of decellularization in our study, as this method significantly reduced the immune response to xenograft tissue, while maintaining subendothelial tissue.

The importance of single nucleotide polymorphisms in interferon gamma receptor-1 gene in pulmonary patients infected with rapid grower mycobacterium.

OBJECTIVE/BACKGROUND: Interferon gamma (IFN-γ) plays a key role in protective immune response against Mycobacterial infection. IFN-γ excretes its antimycobacterial effectors mechanisms by activation of macrophages and dendritic cells via interaction with its receptor complex, that is, a ligand-binding subunit [IFN-γ receptor (IFNGR)1] and an accessory subunit (IFNGR2) on the cell surface. It has been shown that individuals with complete or partial IFNGR1 receptor deficiency are highly susceptible to infection by nontuberculous mycobacteria (NTM), Mycobacterium tuberculosis, and some Salmonella species. In the present study, we aimed to study the IFNGR1 T-56C single nucleotide polymorphism (SNP) in pulmonary patients that were infected with rapid grower mycobacterium. METHODS: Sputum specimens from suspected nontuberculosis pulmonary patients (n=95) were digested and decontaminated using 4% NaOH method. Molecular identification of mycobacterium was then performed by hsp65 genes using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Finally, the host genomic DNA from confirmed patients with rapid-grower mycobacterium (n=20) and control subjects (n=20) were screened for SNPs of IFNGR1 (T-56C) by PCR-RFLP. RESULTS: Out of 95 NTM patients, 20 (21.0%) were infected with rapid grower mycobacterium (RGM). The frequency of Mycobacterium chelonae (n=12) was more than Mycobacterium fortuitum (n=8), but the differences were not statistically significant. Interestingly, 18 patients (90%) had CC genotypes, whereas the remaining two had TC genotypes. The frequency of CC genotypes in the control group was <10% (p<0.05). CONCLUSION: There is a significant association between SNP of IFNGR1 at -56 and susceptibility to rapid grower infection.