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Critical role of Toll-like receptors in pathophysiology of allergic asthma; release assays and the tuberculin skin test

Abstract: Allergic asthma is an airway disease, characterized by reversible bronchoconstriction, chronic inflammation of the airway, and thickness of smooth muscle in the respiratory tract. Asthma is orchestrated by an excessive Th2-adaptive immune response, in which innate immunity plays a key role. Recently TLRs have received more and more attention as they are central to orchestrate the innate immune responses. TLRs are localized as integral membrane or intracellular glycoproteins with those on the cell surface sensing microbial antigens and the ones, localized in intracellular vesicles, sensing microbial nucleic acid species. Having recognized microbial antigens, TLRs conduct the immune response towards a pro- or anti-allergy response. As a double-edged sword, they could initiate either harmful or helpful responses by the immune system in case of allergic asthma. In the current review, we will describe the role of TLRs and their signaling pathways in allergic asthma. © 2016 Elsevier B.V.

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Pattern recognitions receptors in immunodeficiency disorders

Abstract:Objective: Abstract Pattern recognition receptors (PRRs) recognize common microbial or host-derived macromolecules and have important roles in early activation and response of the immune system. Initiation of the innate immune response starts with the recognition of microbial structures called pathogen associated molecular patterns (PAMPs). Recognition of PAMPs is performed by germline-encoded receptors expressed mainly on immune cells termed pattern recognition receptors (PRRs). Several classes of pattern recognition receptors (PRRs) are involved in the pathogenesis of diseases, including Toll-like receptors (TLRs), C-type lectin receptors (CLRs), and Nod-like receptors (NLRs). Patients with primary immune deficiencies (PIDs) affecting TLR signaling can elucidate the importance of these proteins in the human immune system. Defects in interleukin-1 receptor-associated kinase-4 and myeloid differentiation factor 88 (MyD88) lead to susceptibility to infections with bacteria, while mutations in nuclear factor-κB essential modulator (NEMO) and other downstream mediators generally induce broader susceptibility to bacteria, viruses, and fungi. In contrast, TLR3 signaling defects are associated with susceptibility to herpes simplex virus type 1 encephalitis. Other PIDs induce functional alterations of TLR signaling pathways, such as common variable immunodeficiency in which plasmacytoid dendritic cell defects enhance defective responses of B cells to shared TLR agonists. Altered TLR responses to TLR2 and 4 agonists are seen in chronic granulomatous disease (CGD) and X-linked agammaglobulinemia (XLA). Enhanced TLR responses, meanwhile, are seen for TLRs 5 and 9 in CGD, TLRs 4, 7/8, and 9 in XLA, TLRs 2 and 4 in hyper IgE syndrome (HIES), and for most TLRs in adenosine deaminase deficiency. In this review we provide the reader with an update on the role of TLRs and downstream signaling pathways in PID disorders..

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Role of pathogen-associated molecular patterns (PAMPS) in immune responses to fungal infections

Abstract:Background: Abstract Recent years have seen the rise of invasive fungal infections, which are mostly due to the increase in patients. Three major opportunistic fungal species in human are Aspergillus fumigatus, Candida albicans, and Cryptococcus neoformans that pose the biggest concern for these immunocompromised patients mortality. The growing occurrence of opportunistic fungal infections has sparked the interest to understand defense mechanisms against pathogenic fungi. Toll-like receptors (TLRs), as a part of innate immune system, play an important role for recognizing the invading microorganisms and initiating sufficient immune responses. Recent studies have revealed an integrated role for TLR, signaling inactivating immune defense mechanisms against exact fungi. Among TLRs, TLR2 and TLR4 are the major participants in fungi recognition. The present paper highlights the role of TLR participants in fungal recognition as well as their mechanisms.

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Immunoglobulin free light chains in the pathogenesis of lung disorders

Abstract:Background: Abstract Tuberculosis (TB) has usual pattern but challenging diagnosis in pediatric patients. A ten year old girl with chronic dry cough, anorexia and weight loss since 6 month ago was referred to our hospital emergency department with respiratory distress. In physical exam, she was ill with no fever, but had respiratory distress. Patient was intubated and transferred to Intensive care unit (ICU). Her uncle was deceased from unknown pulmonary disease. Patient had respiratory symptoms from 5 years ago and has been misdiagnosed with interstitial lung disease (ILD). Treatment was started by systemic corticosteroids from 6 month ago. Her symptoms were aggravated afterwards. Acid fast staining (AFB) from gastric aspirate was reported to be positive for Mycobacterium tuberculosis (MTB). Combined anti-TB therapy with 4 drugs was started immediately. Unfortunately patient expired after 36 hours. In conclusion, in pediatric patients, the gastric aspirate is the choice samples for diagnosis of TB. Additionally, molecular or other rapid diagnostic test should take into consideration. Reviewing the family history or close contact cases among pediatric patients it looks mandatory.

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Genomic analysis of globally diverse Mycobacterium tuberculosis strains provides insights into the emergence and spread of multidrug resistance

Abstract:Abstract Multidrug-resistant tuberculosis (MDR-TB), caused by drug-resistant strains of Mycobacterium tuberculosis, is an increasingly serious problem worldwide. Here we examined a data set of whole-genome sequences from 5,310 M. tuberculosis isolates from five continents. Despite the great diversity of these isolates with respect to geographical point of isolation, genetic background and drug resistance, the patterns for the emergence of drug resistance were conserved globally. We have identified harbinger mutations that often precede multidrug resistance. In particular, the katG mutation encoding p.Ser315Thr, which confers resistance to isoniazid, overwhelmingly arose before mutations that conferred rifampicin resistance across all of the lineages, geographical regions and time periods. Therefore, molecular diagnostics that include markers for rifampicin resistance alone will be insufficient to identify pre-MDR strains. Incorporating knowledge of polymorphisms that occur before the emergence of multidrug resistance, particularly katG p.Ser315Thr, into molecular diagnostics should enable targeted treatment of patients with pre-MDR-TB to prevent further development of MDR-TB.

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The effects of smoking on treatment outcome in patients newly diagnosed with pulmonary tuberculosis

Abstract: Abstract View references (35) S E T T ING: Smoking is reported to be associated with tuberculosis (TB), but its effect on sputum smear conversion remains a matter for discussion. OBJ E C T I V E : To assess the effects of smoking and smoking cessation on treatment outcomes in patients newly diagnosed with TB in Iran. DESIGN: Newly diagnosed smear-positive TB patients were included in the study. All smokers participated in a smoking cessation programme. Sputum smear status was evaluated at the end of month 2, 5 and 6 of treatment, and smoking status was evaluated at the end of month 2. Differences in smear conversion rates were compared between the three groups, i.e., non-smokers, smokers and quitters. RESULT S : A total of 183 smokers and 151 non-smokers were included. When smoking cessation was assessed after 2 months, 42.6% (78/183) of the smokers were found to have quit. The cure rate at the end of 6 months, precisely compatible with the conversion rate, was significantly higher among non-smokers (P 0.004) and quitters at 2 months (P 0.049) than among persisting smokers (83.4%, 80.8% and 67.6%, respectively). CONCLUS ION: Cure rates in patients newly diagnosed with pulmonary TB were higher in non-smokers and quitters at 2 months than in smokers. Smoking cessation advice should be included in TB control programmes. © 2017 The Union.

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Water-pipe smoke condensate increases the internalization of Mycobacterium Bovis of type II alveolar epithelial cells (A549)

Abstract:Abstract BACKGROUND: Tuberculosis (TB) is a major global health problem, and there is an association between tobacco smoke and TB. Water pipe smoking has become an increasing problem not only in Middle Eastern countries but also globally because users consider it as safer than cigarettes. The presence of high levels of toxic substances in water-pipe smoke may be a predisposing factor that enhances the incidence of pulmonary disorders. For example, uncontrolled macropinocytosis in alveolar epithelial cells following exposure to water-pipe smoke may predispose subjects to pulmonary infection. Here, we studied the effects of water-pipe condense (WPC) on the internalization of Mycobacterium Bovis BCG by macropinocytosis in the alveolar epithelial cell line A549. METHODS: A549 cells were exposed to WPC (4 mg/ml) for 24, 48, 72 and 96 h. Cell viability was studied using the methyl thiazolyldipenyl-tetrazolium bromide (MTT) reduction assay and proliferation by bromodeoxyUridine (BrdU) incorporation. Cells were exposed to FITC-Dextran (1 mg/ml) (as a control) and FITC-BCG (MOI = 10) for 20 min at 37 °C before cells were collected and the uptake of BCG-FITC determined by flow cytometry. Similar experiments were performed at 4 °C as a control. The Rho-associated protein kinase (ROCK) inhibitor Y-27632 (1 μM) was used to assess the mechanism by which WPC enhanced BCG uptake. RESULTS: WPC (4 mg/ml) increased the uptake of BCG-FITC after 72 (1.3 ± 0.1 fold, p < 0.05) and 96 (1.4 ± 0.05 fold, p < 0.05) hours. No effect on BCG-FITC uptake was observed at 24 or 48 h. WPC also significantly increased the uptake of FITC-Dextran (2.9 ± 0.3 fold, p < 0.05) after 24 h. WPC significantly decreased cell viability after 24 (84 ± 2%, p < 0.05), 48 (78±, 3%, p < 0.05), 72 (64 ± 2%, p < 0.05) and 96 h (45 ± 2%, p < 0.05). Y-27632 completely attenuated the increased uptake of BCG by WPC. Cell proliferation showed a decreasing trend in a time-dependent manner with WPC exposure. CONCLUSION: WPC exposure increased epithelial cell endocytosis activity and death as well as enhancing their capacity for macropinocytosis. Our in vitro data indicates possible harmful effects of WPC on the ability of lung epithelial cells to phagocytose mycobacterium.

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Bovis Bacillus Calmette-Guerin (BCG) infection induces exosomal miRNA release by human macrophages

Abstract:Abstract BACKGROUND: Abstract BACKGROUND: Tuberculosis (TB) remains a significant global health concern and its diagnosis is challenging due to the limitations in the specificity and sensitivity of the current diagnostic tests. Exosomes are bioactive 30-100 nm vesicles produced by most cell types and are found in almost all human body fluids. Exosomal microRNAs (miRNAs) can transfer biological information between cells and tissues and may act as potential biomarkers in many diseases. In this pilot study, we assessed the miRNA profile of exosomes released from human monocyte-derived macrophages upon infection with Mycobacterium bovis Bacillus Calmette-Guerin (BCG). METHODS: Human monocytes were obtained from the peripheral blood of three healthy subjects and driven to a monocyte-derived macrophage (MDM) phenotype using standard protocols. MDMs were infected with BCG or left uninfected as control. 72 h post-infection, exosomes were collected from the cell culture medium, RNA was isolated and RNA-seq performed. The raw reads were filtered to eliminate adaptor and primer sequences and the sequences were run against the mature human miRNA sequences available in miRBase. MicroRNAs were identified using an E value <0.01. miRNA network analysis was performed using the DIANA miRNA tool, miRDB and functional KEGG pathway analysis. RESULTS: Infection of MDMs with BCG leads to the release of several exosomal miRNAs. These included miR-1224, -1293, -425, -4467, -4732, -484, -5094, -6848-6849, -4488 and -96 all of which were predicted to target metabolism and energy production-related pathways..

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An Iranian consensus document for nutrition in critically ill patients, recommendations and initial steps toward regional guidelines

Abstract:Background: Obstructive sleep apnea syndrome (OSAS) is a common disorder in which instability of the upper airways leads to a reduction or cessation of airflow during sleep. Sleep disorders such as OSAS increase the risk of occupational accidents and impaired work performance. Sleep deprivation during shift increases the risk of occupational accidents among health care employees. The purpose of this study was to determine the association between occupational injuries in hospital staff and the risk of sleep apnea. Materials and Methods: This cross-sectional study was conducted on hospital staff of Masih Daneshvari Hospital in 2012. In this study, the hospital staff's (715) response to the Berlin questionnaire plus additional information including a history of an occupational accident, night shifts, less than four hours of night sleep, history of smoking, chronic disease and quality of sleep were assessed. Information obtained was analyzed using SPSS 15. Results: In general, 27.6% reported a history of occupational accidents. The incidence of occupational accidents in the high-risk group for sleep apnea was significantly higher than the low-risk group (OR=2.736, CI=1.522-4.917, P=0.001). The results of logistic regression analysis also showed a statistically significant association between occupational accidents and risk of sleep apnea (OR = 2.247, CI = 1.194-4.231, P= 0.012). Conclusion: This study showed that the incidence of occupational accidents in the hospital employees is strongly related to the probability of OSA. Therefore, special attention should be directed to respiratory sleep disorders in order to reduce occupational injuries at hospitals. © 2015 NRITLD, National Research Institute of Tuberculosis and Lung Disease, Iran.

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Distribution scheme of antituberculosis drug resistance among HIV patients in a referral centre over 10 years

Abstract:Middle East respiratory syndrome coronavirus (MERS-CoV) Infection, has caused recurrent outbreaks worldwide. It is associated with severe morbidity and mortality, and is not treatable with the currently available antiviral therapies. We present a case of a 43 year-old male healthcare provider, who admitted with productive cough, dyspnea, myalgia, pleuritic chest pain and fever. Computed tomography (CT) showed bilateral ground glass opacities and consolidation. Sputum polymerase chain reaction (PCR) for MERS-coronavirus was positive. © 2015 NRITLD.

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Cost of tuberculosis treatment: Evidence from Irans health system

Abstract:Acremonium spp. cause human superficial infections including mycetoma, onychomycosis and keratitis. There are a few reports of systemic involvement in immunocompromised patients. However, isolated pulmonary infection in otherwise healthy hosts has never been reported in the literature. Herein, we report a 59 year-old diabetic man with non-resolving pneumonia due to Acremonium spp. and provide a consensus review of the published clinical cases of systemic and respiratory tract infections. © 2015 NRITLD.

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Acute Epstein -Barr virus hepatitis without mononucleosis syndrome: A case report

Abstract:Objective: Patients with chronic physical diseases sometimes show increased loss of function; such patients need more care. Anxiety is a well-known symptom that is prevalent among chronic obstructive pulmonary disease patients that can prolong and increase the risk of hospitalization. The purpose of this study was to evaluate the severity of anxiety in the mentioned patients and to examine the presence of symptoms and appropriate treatment strategies to understand the role of psychological functions in physical patients. Methods: This was a cross sectional study conducted in Masih Daneshvari Hospital. One hundred forty- three patients entered into the project by accessible method and signed the informed consent; they filled demographic information and Hamilton anxiety and depression questionnaires. Data were analyzed by SPSS-16. Results: Of the participants, 68% were above 60 years of age; 78% were male; 89% were married; and 38% were self-employed. Also, among the participants, 51% were illiterate; 72% had history of smoking; 46% had history of substance abuse; and 49% had moderate to severe anxiety disorder. Moreover, of the patients with severe anxiety, 41.3% had severe muscle spasms; and severe sleeplessness was found in 38.5% of those with severe anxiety disorder. Severe anxiety related symptoms were found in 20.3% of the patients with severe anxiety disorder. Depressed mood was found in 27.3% of the patients with severe anxiety disorder. Severe physical and muscular signs were found in 35.7% of those with severe anxiety disorder. Conclusion: According to our findings, many chronic diseases such as chronic obstructive pulmonary disease may contain anxiety and depression which result in vulnerability. Therefore, evaluation of anxiety in such patients is of importance for alleviating the disease.

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Recurrent drug-induced hepatitis in tuberculosis-comparison of two drug regimens

Abstract:Background: Stress-related mucosal disease occurs in many critically ill-patients within 24 h of admission. Proton pump inhibitor therapy has been documented to produce more potent inhibition of gastric acid secretion than histamine 2 receptor antagonists. This study aimed to compare extemporaneous preparations of omeprazole, pantoprazole oral suspension and intravenous (IV) pantoprazole on the gastric pH in intensive care unit patients. Materials and Methods: This was a randomized single-blind-study. Patients of ≥ 16 years of age with a nasogastric tube, who required mechanical ventilation for ≥ 48 h, were eligible for inclusion. The excluded patients were those with active gastrointestinal bleeding, known allergy to omeprazole and pantoprazole and those intolerant to the nasogastric tube. Fifty-six patients were randomized to treatment with omeprazole suspension 2 mg/ml (40 mg every day), pantoprazole suspension 2 mg/ml (40 mg every day) and IV pantoprazole (40 mg every day) for up to 14 days. Gastric aspirates were sampled before and 1-2.5 h after the drug administration for the pH measurement using an external pH meter. Data were analyzed using SPSS (version 21.0). Results: In this study, 56 critically ill-patients (39 male, 17 female, mean age: 61.5 ± 15.65 years) were followed for the control of the gastric pH. On each of the 14 trial days the mean of the gastric pH alteration was significantly higher in omeprazole and pantoprazole suspension-treated patients than in IV pantoprazole-treated patients (P < 0.001). Conclusion: Omeprazole and pantoprazole oral suspension are more effective than IV pantoprazole in increasing the gastric pH.

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Comparison between pulmonary and extrapulmonary tuberculosis in adolescents

Abstract:Multidrug-resistant (MDR) and extensively drug-resistant (XDR) tuberculosis (TB) are increasing globally. Treatment options for these patients are very limited. Although treatment of these patients with standardized regimen is associated with high mortality and morbidity, rational usage of new drugs might be promising. In this study we will review epidemiology of XDR-TB and TDR-TB in Iran and the world. © 2015, Pediatric Infections Research Center.

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Antifungal resistant gastrointestinal basidiobolomycosis without eosinophilia: A case report

Abstract:Tuberculosis (TB) is considered a major worldwide health problem with 10 million new cases diagnosed each year. Our understanding of TB immunology has become greater and more refined since the identification of Mycobacterium tuberculosis (MTB) as an etiologic agent and the recognition of new signaling pathways modulating infection. Understanding the mechanisms through which the cells of the immune system recognize MTB can be an important step in designing novel therapeutic approaches, as well as improving the limited success of current vaccination strategies. A great challenge in chronic disease is to understand the complexities, mechanisms, and consequences of host interactions with pathogens. Innate immune responses along with the involvement of distinct inflammatory mediators and cells play an important role in the host defense against the MTB. Several classes of pattern recognition receptors (PRRs) are involved in the recognition of MTB including Toll-Like Receptors (TLRs), C-type lectin receptors (CLRs) and Nod-like receptors (NLRs) linked to inflammasome activation. Among the TLR family, TLR1, TLR2, TLR4, and TLR9 and their down-stream signaling proteins play critical roles in the initiation of the immune response in the pathogenesis of TB. The inflammasome pathway is associated with the coordinated release of cytokines such as IL-1β and IL-18 which also play a role in the pathogenesis of TB. Understanding the cross-talk between these signaling pathways will impact on the design of novel therapeutic strategies and in the development of vaccines and immunotherapy regimes. Abnormalities in PRR signaling pathways regulated by TB will affect disease pathogenesis and need to be elucidated. In this review we provide an update on PRR signaling during M. tuberculosis infection and indicate how greater knowledge of these pathways may lead to new therapeutic opportunities. © 2014, The Author(s).

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Paecilomyces formosus Infection in an Adult Patient with Undiagnosed Chronic Granulomatous Disease

Abstract:Kaposi's sarcoma (KS) is a malignant proliferation of the endothelial cells. It typically presents with several vascular nodules on the skin and other organs. The penile localization of KS, particularly on the shaft area, is exceptional. We report an HIV-positive 34-year-old man who had multiple purplish-black plaques on his extremities and several small violaceous macules on the glans and shaft of the penis. Kaposi's sarcoma was diagnosed by histopathology. © 2015 Indian Journal of Dermatology.

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Risk factors for readmission to hospital in patients with tuberculosis in Tehran, Iran: three-year surveillance

Abstract:Background: Tuberculosis (TB) is one of the most challenging public health burdens in the world. Recent research demonstrated high prevalence of mental disorders in TB patients and their caregivers. The purpose of this study was to assess mental health of TB patients and their caregivers in Iran before and after a two-week inpatient treatment and to determine the prevalence of psychological problems in these groups. Materials and Methods: A standardized questionnaire (SCL-90) was used to assess psychological symptoms in 146 hospitalized TB patients and their caregivers (n=89). Furthermore, the scores of both target groups were compared with those of a group of healthy individuals (n=85). Results: The mean scores before the start of the initial treatment of the patients were significantly lower for paranoid ideation (P=0.038) and hostility (P= 0.046), and the scores of depression (P=0.046) and somatization (P=0.001) were significantly higher than those of the healthy individuals. The patients scored significantly higher than the caregivers on depression (0.047) and somatization (P< 0.001), whereas the caregivers scored higher than the healthy individuals on paranoid ideation (P= 0.044) and hostility (P= 0.034). Multiple linear regression showed that age, educational level and marital status were factors affecting the mental health of TB patients and their caregivers. The variance in psychological symptoms of the patients was between 10% (paranoid ideation) and 27% (hostility) of the variance in the symptoms of their caregivers. Conclusion: Tuberculosis control and treatment programs should not only address issues like continued respiratory symptoms, but should also focus on mental health in TB patients and their caregivers. © 2015 NRITLD, National Research Institute of Tuberculosis and Lung Disease, Iran.

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