Quantitative Insight into PCA Formation following Different Chlorhexidine Activation Methods in Endodontic Treatment

The aim of the study was a quantitative analysis of p-chloroaniline (PCA) formation during 2% CHX activation with US and MDI methods in a root canal-like environment with the HPLC-DAD method and, thus, a safety assessment of US and MDI agitation of CHX in endodontic treatment. Two percent CHX was activated with the US method using ISO 30 and 35 K-file, and the MDI method using ISO 30.06 and 35.06 GP cones for 15, 30, 60, and 90 s. PCA concentration was assessed with the HPLC-DAD method. PCA concentration was also assessed for 2% CHX after 0, 3, 18, and 21 days of storage in ambient conditions. PCA was detected in all samples in all methods of activation. The concentration of PCA was dependent on time of activation in US ISO 30 and ISO 35 group (p < 0.05). In the MDI ISO 30.06 and ISO 35.06 groups, a similar trend was observed but without statistical significance (p > 0.05). PCA was detected in shelf-stored 2% CHX and the concentration was related to the time of storage. PCA is released after CHX activation with US and MDI, but mean concentrations are not higher than those observed from self-degradation of shelf-stored 2% CHX.

The Importance of Nutritional Aspects in the Assessment of Inflammation and Intestinal Barrier in Patients with Inflammatory Bowel Disease

Intestinal inflammation in inflammatory bowel disease (IBD) is closely linked to nutrition. This study aimed to evaluate associations between nutritional, inflammatory, and intestinal barrier parameters in patients with IBD. We assessed nutritional status, fecal short-chain fatty acid profile, serum cytokine levels, and mRNA expression of enzymes and tight junction proteins in intestinal biopsies obtained from 35 patients, including 11 patients with inactive IBD, 18 patients with active IBD, and six controls. Patients with active IBD were characterized by hypoalbuminemia, fluctuations in body weight, and restriction of fiber-containing foods. In addition, they had significantly reduced levels of isovaleric acid and tended to have lower levels of butyric, acetic, and propionic acids. Patients with active IBD had higher mRNA expression of peroxisome proliferator-activated receptor γ and inducible nitric oxide synthase, and lower mRNA expression of claudin-2 and zonula occludens-1, compared with patients with inactive IBD. Moreover, patients with a body mass index (BMI) of ≥25 kg/m2 had higher median tumor necrosis factor-α levels that those with a lower BMI. We comprehensively evaluated inflammatory parameters in relation to IBD activity and nutritional status. The discrepancies between proinflammatory and anti-inflammatory parameters depending on IBD activity may be related to nutritional factors, including diet and abnormal body weight.

Association between fecal levels of Short-Chain Fatty Acids and serum Pro- and Anti-Inflammatory Cytokines in patients with Inflammatory Bowel Disease

INTRODUCTION

Inflammatory bowel disease (IBD) represents a group of chronic inflammatory disorders characterized by dysbiosis and altered short-chain fatty acid (SCFA) level. The association between individual SCFA levels and cytokine levels is unknown.

OBJECTIVES

We aimed to determine the fecal SCFA levels in patients with IBD in relation to disease severity and the serum levels of pro- and anti-inflammatory cytokines.

PATIENTS AND METHODS

The study included 61 patients with IBD (inactive, 22; active, 39) and 16 controls. Fecal levels of organic acids (acetic, lactic, propionic, butyric, isovaleric, isobutyric, and valeric), serum levels of tumor necrosis factor-alpha (TNF-α), interleukin-10 (IL-10), IL-17, and IL-22, complete blood count and C-reactive protein (CRP) were measured.

RESULTS

Patients with active IBD had reduced butyric, acetic, valeric, and isovaleric acid levels and elevated lactic acid levels in stool. Hemoglobin levels were positively correlated with the levels of acetic and butyric acids (R = 0.266 and R = 0.346, respectively; P <0.05). In addition, CRP levels were inversely correlated with butyric acid levels (R = -0.573; P <0.05). Higher serum TNF-α levels were observed in patients with active IBD compared with controls (6.64 pg/ml vs 2.05 pg/ml, P <0.05). No relationship was noted between the SCFA profile and cytokine levels.

CONCLUSIONS

The study showed that determination of SCFA levels can be used to evaluate the activity of IBD. The relationship between individual SCFA and cytokine levels seems to be complex and requires further studies.

Association between Fecal Short-Chain Fatty Acid Levels, Diet, and Body Mass Index in Patients with Inflammatory Bowel Disease

Simple Summary

Inflammatory bowel disease (IBD) is a chronic disorder of the gastrointestinal tract associated with gut inflammation and a disturbance in the amount of bacteria living in the human intestines. As a result, there is a reduction in the production of bacterial metabolites, especially short-chain fatty acids (SCFAs), which are formed from dietary fiber. The aim of our study was to assess the relationship between body mass index (BMI), the type of diet used, and changes in fecal SCFA levels in patients with IBD. We enrolled 61 patients with IBD and 16 patients as a control group. We asked all participants about their daily diet, using the simplified FF questionnaire, and measured the levels of SCFA in their stool samples. Our results revealed that underweight subjects had higher levels of isobutyric acid, whereas those with excessive weight had lower level of butyric, isovaleric, and propionic acids. Furthermore, we observed higher levels of valeric acid in controls than in IBD patients. However, we did not observe a relationship between diet habits and fecal SCFA levels. In conclusion, we demonstrated that BMI is associated with SCFA levels in patients with IBD.

Abstract

Disturbances in the production of bacterial metabolites in the intestine have been reported in diseases associated with dysbiosis, such as inflammatory bowel diseases (IBDs) that include two conditions: Crohn disease (CD) and ulcerative colitis (UC). Short-chain fatty acids (SCFAs) are the main dietary-fiber-derived bacterial metabolites associated with the course of intestinal inflammation. In this study, we assessed the relationship between body mass index (BMI), the type of diet used, and changes in fecal SCFA levels in patients with IBD. We performed nutritional assessments using a nutritional questionnaire and determined fecal SCFA levels in 43 patients with UC, 18 patients with CD, and 16 controls. Our results revealed that subjects with a BMI > 24.99 kg/m² had higher levels of isobutyric acid, whereas those with a BMI < 18.5 kg/m² had lower level of butyric, isovaleric, and propionic acids. Furthermore, we observed higher levels of valeric acid in controls than in IBD patients. We did not reveal a relationship between a specific SCFA and the type of diet, but eating habits appear to be related to the observed changes in the SCFA profile depending on BMI. In conclusion, we demonstrated that BMI is associated with SCFA levels in patients with IBD.

A Perspective of the Comprehensive and Objective Assessment of Analytical Methods Including the Greenness and Functionality Criteria: Application to the Determination of Zinc in Aqueous Samples

The recently proposed concept of White Analytical Chemistry (WAC), referring to the Red-Green-Blue color model, combines ecological aspects (green) with functionality (red and blue criteria), presenting the complete method as “white”. However, it is not easy to carry out an overall quantitative evaluation of the analytical method in line with the WAC idea in an objective manner. This paper outlines the perspective of the future development of such a possibility by attempting to answer selected questions about the evaluation process. Based on the study consisting in the evaluation of selected model methods by a group of 12 independent analysts, it was shown how well individual criteria are assessed, whether the variability of assessments by different people is comparable for each criterion, how large it is, and whether averaging the scores from different researchers can help to choose the best method more objectively.

The chemistry and histology of sexually dimorphic mental glands in the freshwater turtle, Mauremys leprosa

Despite evidence from anatomy, behavior and genomics indicating that the sense of smell in turtles is important, our understanding of chemical communication in this group is still rudimentary. Our aim was to describe the microanatomy of mental glands (MGs) in a freshwater turtle, Mauremys leprosa (Geoemydidae), and to assess the chemical composition of their secretions with respect to variation among individuals and between sexes. MGs are paired sac-like organs on the gular region of the neck and are dimorphic in this species with males having fully functional holocrine glands while those of females appear non-secretory and vestigial. In adult males, the glandular epithelium of the inner portion of the gland provides exocytotic products as well as cellular debris into the lumen of the gland. The contents of the lumen can be secreted through the narrow duct portion of the gland ending in an orifice on the surface of the skin. Females have invaginated structures similar in general outline to male glands, but lack a glandular epithelium. Using gas chromatography coupled to mass spectrometry, we identified a total of 61 compounds in mental gland secretions, the most numerous being carboxylic acids, carbohydrates, alkanes, steroids and alcohols. The number of compounds per individual varied widely (mean (median) ± SD = 14.54 (13) ± 8.44; min = 3; max = 40), but only cholesterol was found in all samples. We found that the relative abundances of only six chemicals were different between the sexes, although males tended to have larger amounts of particular compounds. Although the lipid fraction of mental gland secretions is rich in chemical compounds, most occur in both sexes suggesting that they are metabolic byproducts with no role in chemical signaling. However, the relative amounts of some compounds tended to be higher in males, with significantly larger amounts of two carboxylic acids and one steroid, suggesting their putative involvement in chemical communication.

New approach to H-point standard addition method for detection and elimination of unspecific interferences in samples with unknown matrix

A novel method for correction of unknown unspecific (additive) interferences was developed in sequential injection analysis (SIA) using a Lab on Valve module (LOV) with spectrophotometric detection. The method implements a novel idea to calibrate by the standard addition method in several different chemical conditions created in such a way to measure different signal for an analyte and unchanged signal for interferents causing additive effect. This approach, being an enhancement of the H-point standard addition method (HPSAM), enables to quantify unbiased concentration of an analyte in the presence of unknown interferences. The method was tested on the example of the determination of ascorbic acid in soft drinks and juices basing on reduction of Fe(III) to Fe(II) and reaction of the latter with o-phenanthroline to the ferroin complex absorbing at 512.0nm. The analytical utility of the method has been verified and confirmed by the spectrophotometric determination of total acidity in rose and red wines in the presence of bromothymol blue absorbing at 616.0nm. Calibration solutions were prepared automatically in the designed flow system. Ascorbic acid was determined with LOD of 1.4mgL^-1 and LOQ of 4.2mgL^-1 within linear working range up to 80mgL^-1, while in case of the determination of total acidity the values of 4.2, 11.8 and 100, respectively, were obtained. A sample was consumed in volumes of 400 and 1000µL in both cases. The analyses are simple, "green", and non-expensive. The developed method is readily applicable to analysis of real samples of complex unknown matrices and adaptable to different analytical methods.

Development of potential candidate reference materials for drugs in bottom sediment, cod and herring tissues

Regular use of a reference material and participation in a proficiency testing program can improve the reliability of analytical data. This paper presents the preparation of candidate reference materials for the drugs metoprolol, propranolol, carbamazepine, naproxen, and acenocoumarol in freshwater bottom sediment and cod and herring tissues. These reference materials are not available commercially. Drugs (between 7 ng/g and 32 ng/g) were added to the samples, and the spiked samples were freeze-dried, pulverized, sieved, homogenized, bottled, and sterilized by γ-irradiation to prepare the candidate materials. Procedures for extraction and liquid chromatography coupled with tandem mass spectrometry were developed to determine the drugs of interest in the studied material. Each target drug was quantified using two analytical procedures, and the results obtained from these two procedures were in good agreement with each other. Stability and homogeneity assessments were performed, and the relative uncertainties due to instability (for an expiration date of 12 months) and inhomogeneity were 10-25% and 4.0-6.8%, respectively. These procedures will be useful in the future production of reference materials.

Procedure optimization for extracting short-chain fatty acids from human faeces

Short-chain fatty acids play an important role in the physiology and metabolism of the colon. Disturbed balance of such compounds in human gut can significantly contribute to etiological factors of various gastrointestinal disorders and it may also increase the risk of developing cancer or cardiovascular diseases. The aim of the study was to select the optimal parameters for acetic, propionic and butyric acids extraction from stool samples. The experimental conditions were optimized with respect to the solvent sample shacking time, sample ultrasounds (Ultrasound-Assisted Extraction, UAE) exposure time and the number of extractions from the particulate stool samples. The screening of experimental parameters was conducted with fractional factorial design of experiments, namely 3(3-1). The optimal conditions for UAE were found, namely ultrasound digestion time of 40 min (at 35°C), shaking time of 4 min, and the three subsequent extractions.

n-3 Fatty acids regulate the inflammatory-state related genes in the lung epithelial cells exposed to polycyclic aromatic hydrocarbons

BACKGROUND

Chronic airway inflammation is coordinated by a complex of inflammatory mediators, including eicosanoids. The aim of this study was to evaluate the impact of polycyclic aromatic hydrocarbons (PAHs) on the human lung epithelial carcinoma A549 cells supplemented with docosahexaenoic (DHA) and eicosapentaenoic (EPA) acids.

METHODS

We analyzed the influence of DHA, EPA and/or benzo(a)pyrene (BaP), chrysene (Chr), fluoranthene (Flu) and benzo(a)anthracene (Baa) treatment on the fatty acids (FAs) profile and the formation of isoprostanes. We studied the cyclooxygenase-2, FP-receptor, peroxisome proliferator-activated receptors PPARδ and PPARγ, transcription factor NF-кB p50 and p65 expression by Western blot, phospholipase A2 (cPLA2) activity, as well as aryl hydrocarbon receptor (AHR), cytochrome P450 (CYP1A1), phospholipase A2 (PLA2G4A) and prostaglandin synthase 2 (PTGS2) gene expression by qRT-PCR.

RESULTS

DHA or EPA supplementation and BaP or Baa treatment resulted in a higher level of PGF3α. COX-2 expression was decreased while PPARδ expression and cPLA2 activity was increased after fatty acid supplementation and PAHs treatment. DHA and EPA up-regulated AHR and PLA2G4A genes.

CONCLUSIONS

Supplementation with n-3 FAs resulted in changes of inflammatory-state related genes in the lung epithelial cells exposed to PAHs. The altered profile of lipid mediators from n-3 FA as well as repression of the COX-2 protein by n-3 PUFAs in A549 cells incubated with PAHs suggests anti-inflammatory and pro-resolving properties of DHA and EPA. It remains to be shown whether these pleiotropic and protective actions of n-3 FAs contribute to fish oil's therapeutic effect in asthma.