Inflammatory bowel disease : determinants related to gut microbiota

Inflammatory bowel disease (IBD) is a chronic and idiopathic disorder that causes inflammation in the gastrointestinal tract. Overall, it can be classified into two types: ulcerative colitis (UC) and Crohn's disease (CD). The causes of IBD have been extensively studied, with heredity, lifestyle, and environmental factors being identified as possible contributors. These factors can trigger an imbalance in the bacterial flora in the colon, which is increasingly thought to play a crucial role in the development of IBD. As dysbiosis in the gut microbiota has been frequently reported in inflammatory bowel disease, it has been proposed that both UC and CD may be caused by an auto-immune response to gut bacteria in genetically susceptible individuals. However, the exact aetiology of these diseases is still largely unknown. The aim of this thesis was to investigate epidemiological aspects of surgical abdominal procedures and possible biochemical markers associated with gut microbiota, in relation to IBD. In Paper I, we investigated the association between juvenile appendicitis, treated with appendectomy or conservatively treated without surgery, and adult risk of IBD. This, nation-wide, population-based retrospective cohort study, based on Swedish national registers, included all individuals with a diagnosed appendicitis before the age of 16, during the time-period 1973-1996, and matched controls. The study population was followed until 2017 for any development of UC and CD. We found that childhood appendicitis with appendectomy was associated with lower risk of UC (aHR 0.30 95% CI 0.25-0.36) and CD (aHR 0.82 95% CI 0.68-0.97), whereas conservative treatment was associated with lower risk of adult UC (aHR 0.29 95% CI 0.12-0.69), only, compared to unexposed individuals. Our findings warrant further research of the appendix in relation to gut microbiota and IBD pathogenesis. In Paper II, we investigated the association between bariatric surgery and new onset of IBD. This population-based retrospective cohort study included Swedish individuals registered in the Scandinavian Obesity Surgery Registry who underwent primary Roux-en-Y gastric bypass (RYGB) or sleeve gastrectomy (SG) during 2007 – 2018 and matched controls. The study population was followed up until 2019 to determine the development of CD and UC. We found that individuals operated on with RYGB had an increased risk of later development of CD (HR 1.8 95% CI 1.5 - 2.2) whereas individuals who underwent SG had an increased risk of UC (HR 1.8 95% CI 1.1-3.1). The findings should encourage further studies on surgical procedures for obesity and their effect on gut microbiota and development of IBD. In Paper III, the aim was to analyse plasma concentrations of short chain fatty acids (SCFA) in relation to CD and UC and to evaluate SCFA as a potential biomarker for IBD. This cross-sectional study included 132 and 119 individuals with CD and UC respectively and 205 controls. Although we found lower plasma concentrations of succinic acid among individuals with CD and UC in comparison to controls in univariate analysis, the difference did not remain after adjusting for sex, age and dietary factors. For all other SCFA, no differences could be found between the groups. In conclusion, CD and UC were not associated with alterations in plasma SCFA concentration. In Paper IV, we aimed to assess alterations of plasma bile acid (BA) profiles in association to CD. This cross-sectional study included 88 individuals with CD and 88 controls. CD was found to be associated with lower concentrations of most secondary BA, particularly derivatives of deoxycholic acid and lithocholic acid. Moreover, plasma concentration of secondary BA among participants with active CD was lower in comparison to participants with CD in remission. We concluded that the immune dysfunction in CD may be associated with altered bile acid composition in blood plasma

Phosphosulfonic acid, an efficient solid acid catalyst for the one-pot preparation of 14-aryl-14H-dibenzo[a,j]xanthenes and 1,8-dioxo-octahydro-xanthenes under solvent-free conditions

An expeditious procedure for the synthesis of 14- aryl-14H-dibenzo[a,j]xanthenes and 1,8-dioxo-octahydro-xanthenes through one-pot pseudo three component condensation of β-naphthol or dimedone with various aryl aldehydes is described. This greener protocol is catalyzed by phosphosulfonic acid, and proceeds efficiently in the absence of any organic solvent under optimized, mild, green and environmentally benign reaction conditions in high yields within 20-55 minutes

Polyvinyl Sulfuric Acid: A Novel Solid Acid Catalyst for Preparation of Symmetrical Ethers and Theoretical Calculation

In this paper, polyvinyl sulfuric acid as a novel solid acid was easily prepared by simple mixing of polyvinyl alcohol with chlorosulfonic acid at room temperature. The facile procedure for conversion of benzylic alcohols to the corresponding symmetrical ethers in the presence of this solid acid under solvent free conditions was investigated. Results showed that the solid acid was an appropriate catalytic agent for this condensation reaction. It also showed its ability to produce the products in short reaction times while having high isolated yields.Also theoretical calculation by DFT method with B3LYP using 6-31G** basis sets was done. Based on the calculation, Transition state is a primary carbocation that the positive charge is dispersed by the benzene ring. The dipole moment of transition state is 0.2226D and the total energy of produced carbonation is more than symmetrical ether and alcohol, as the results the produced carbocation via SN1 is an appropriate transition state

B(HSO4)3: a novel and efficient solid acid catalyst for the regioselective conversion of epoxides to thiocyanohydrins under solvent-free conditions

B(HSO4)3 was easily prepared and used as a novel and efficient solid acid catalyst for conversion of epoxides to the corresponding thiocyanohydrins under solvent-free conditions with high isolated yields. The salient features of this methodology are cheaper process, easy availability of the catalyst, versatility, and high regioselectivity of the procedure

A Population-Based Study of Unfavorable Prognostic Factors Associated With Pyogenic Liver Abscess

BackgroundPyogenic liver abscess (PLA) is a rare entity that is associated with substantial mortality and morbidity. Our objective was to investigate variables associated with mortality and subsequent PLA in patients diagnosed with PLA in southern Sweden.MethodsWe conducted a population-based observational study comprising all episodes of PLA that occurred between 2011 and 2020 in the county of Skåne, southern Sweden. The primary outcome was defined as all-cause 90-day mortality and the secondary outcome was defined as the occurrence of a subsequent PLA.ResultsA total of 452 episodes of PLA occurred in 360 patients during the study period. The 90-day mortality rate was 16% (n = 58) and the subsequent PLA rate was 20% (n = 92). In a multivariable logistic regression model, female sex (odds ratio [OR], 2.0 [95% confidence interval {CI}, 1.1–3.9]), malignancy (OR, 3.7 [95% CI, 1.9–7.1]), liver failure (OR, 6.3 [95% CI, 2.7–14.5]), and polymicrobial findings (OR, 3.8 [95% CI, 2.2–6.9]) were associated with death within 90 days (P < .05). Male sex (OR, 2.1 [95% CI, 1.2–3.6]), malignancy (OR, 2.1 [95% CI, 1.3–3.6]), age (64–74 years: OR, 2.5 [95% CI, 1.3–4.8]), and chronic liver disease (OR, 3.0 [95% CI, 1.4–6.5]) were associated with the risk of subsequent PLA (P ≤ .01).ConclusionsIdentifying different clinical variables associated with an unfavorable outcome may improve the management and treatment of patients with PLA and thus prevent the risk of death and subsequent PLA

Synthesis and Characterization of a Novel Nanosilica Supported Bipyridinium Chloride Nanocomposite and its Application as a Basic Catalyst in the One-pot Preparation of Tetrahydrobenzo[b]pyran, Dihydropyrano[3,2-c]chromene and Dihydropyrano[4,3-b]pyran Derivatives

A novel rice-husk-silica supported n-propyl bipyridinium chloride (RHPrBPCl) has been prepared. Due to the basicity of RHPrBPCl, it was decided to evaluate its catalytic activity in the one-pot preparation of tetrahydrobenzo[b]pyran, dihydropyrano[3,2-c]chromene and dihydropyrano[4,3-b]pyran derivatives. The catalyst was characterized by FT-IR, SEM and TGA analyses. This methodology offers several advantages including easy work-up procedure, high yields of the products, short reaction times, recyclable catalyst and green reaction medium

Validity of bioconjugated silica nanoparticles in comparison with direct smear, culture, and polymerase chain reaction for detection of Mycobacterium tuberculosis in sputum specimens

Alireza Ekrami1, Ali Reza Samarbaf-Zadeh2, Azar Khosravi1, Behrooz Zargar3, Mohamad Alavi1, Mansor Amin2, Alireza Kiasat3 1Infectious and Tropical Diseases Research Center, Ahvaz Jundishapur University of Medical Sciences, 2Department of Microbiology, School of Medicine, Ahvaz Jundishapur University of Medical Sciences, 3Department of Chemistry, School of Science, Shahid Chamran University, Ahvaz, Iran Background: Tuberculosis is a public health problem worldwide, and new easy to perform diagnostic methods with high accuracy are necessary for optimal control of the disease. Recently, fluorescent silica nanoparticles (FSNP) has attracted immense interest for the detection of pathogenic microorganisms. The aim of this study was to detect Mycobacterium tuberculosis in clinical samples using bioconjugated FSNP compared with microscopic examination, polymerase chain reaction (PCR), nested PCR, and culture as the gold standard. Methods: In total, 152 sputum specimens were obtained from patients who were suspected to have pulmonary tuberculosis. All samples were examined by the four techniques described. Results: The assay showed 97.1% sensitivity (95% confidence interval [CI] 91&amp;ndash;99.2) and 91.35% specificity (CI 78.3&amp;ndash;97.1). Furthermore, assays using variable bacterial concentrations indicated that 100 colony forming units/mL of M. tuberculosis could be detected. There were no differences between the results obtained from two types of mouse monoclonal antibody against Hsp-65 and 16 KDa antigens. Conclusion: We performed this assay in a large number of clinical samples to confirm the diagnostic specificity and sensitivity of the test and can recommend its application for diagnosis of M. tuberculosis. We believe that this method is more convenient for routine diagnosis of M. tuberculosis in sputum and will be more easily applicable in the field, and with sufficient sensitivity. Keywords: Mycobacterium tuberculosis, fluorescent silica nanoparticles, bioconjugation, IS611

Polyvinyl Sulfuric Acid: A Novel Solid Acid Catalyst for Preparation of Symmetrical Ethers and Theoretical Calculation

In this paper, polyvinyl sulfuric acid as a novel solid acid was easily prepared by simple mixing of polyvinyl alcohol with chlorosulfonic acid at room temperature. The facile procedure for conversion of benzylic alcohols to the corresponding symmetrical ethers in the presence of this solid acid under solvent free conditions was investigated. Results showed that the solid acid was an appropriate catalytic agent for this condensation reaction. It also showed its ability to produce the products in short reaction times while having high isolated yields.Also theoretical calculation by DFT method with B3LYP using 6-31G** basis sets was done. Based on the calculation, Transition state is a primary carbocation that the positive charge is dispersed by the benzene ring. The dipole moment of transition state is 0.2226D and the total energy of produced carbonation is more than symmetrical ether and alcohol, as the results the produced carbocation via SN1 is an appropriate transition state

Port implantation-related bloodstream infection caused by Wickerhamomyces myanmarensis: A case report

Background and Purpose: Wickerhamomyces myanmarensis is a new opportunistic yeast previously named Pichai myanmarensis, which belongs to the order Saccharomycetales. Since its discovery, one environmental isolate of W. myanmarensis has been reported from Myanmar, and one clinical sample from Iran.Case Report:We report a case of bloodstream infection related to an implantable venous access port. W. myanmarensis was isolated from patient's blood after chemotherapy, which was meant to control and heal T-cell lymphoblastic lymphoma. Broth dilution minimum inhibitory concentrations were performed according to the CLSI M27-A3 document. The patient recovered with intravenous voriconazole and was discharged with the recommended prescription of oral voriconazole as a maintenance drug.Conclusion: So far, only one case of W. myanmarensis fungemia has been reported in the world in 2019. This is the second case of bloodstream infection with this yeast from a patient undergoing chemotherapy in Iran

Laparoscopy in management of appendicitis in high-, middle-, and low-income countries: a multicenter, prospective, cohort study.

BACKGROUND: Appendicitis is the most common abdominal surgical emergency worldwide. Differences between high- and low-income settings in the availability of laparoscopic appendectomy, alternative management choices, and outcomes are poorly described. The aim was to identify variation in surgical management and outcomes of appendicitis within low-, middle-, and high-Human Development Index (HDI) countries worldwide. METHODS: This is a multicenter, international prospective cohort study. Consecutive sampling of patients undergoing emergency appendectomy over 6 months was conducted. Follow-up lasted 30 days. RESULTS: 4546 patients from 52 countries underwent appendectomy (2499 high-, 1540 middle-, and 507 low-HDI groups). Surgical site infection (SSI) rates were higher in low-HDI (OR 2.57, 95% CI 1.33-4.99, p = 0.005) but not middle-HDI countries (OR 1.38, 95% CI 0.76-2.52, p = 0.291), compared with high-HDI countries after adjustment. A laparoscopic approach was common in high-HDI countries (1693/2499, 67.7%), but infrequent in low-HDI (41/507, 8.1%) and middle-HDI (132/1540, 8.6%) groups. After accounting for case-mix, laparoscopy was still associated with fewer overall complications (OR 0.55, 95% CI 0.42-0.71, p < 0.001) and SSIs (OR 0.22, 95% CI 0.14-0.33, p < 0.001). In propensity-score matched groups within low-/middle-HDI countries, laparoscopy was still associated with fewer overall complications (OR 0.23 95% CI 0.11-0.44) and SSI (OR 0.21 95% CI 0.09-0.45). CONCLUSION: A laparoscopic approach is associated with better outcomes and availability appears to differ by country HDI. Despite the profound clinical, operational, and financial barriers to its widespread introduction, laparoscopy could significantly improve outcomes for patients in low-resource environments. TRIAL REGISTRATION: NCT02179112