Methanol extract of Iraqi Kurdistan Region Daphne mucronata as a potent source of antioxidant, antimicrobial, and anticancer agents for the synthesis of novel and bioactive polyvinylpyrrolidone nanofibers.

In this study, aqueous, ethanol, methanol, and hexane extracts from Iraqi Kurdistan Region Daphne mucronata were prepared due to the numerous applications and development of nanofibers in biological and medical fields, including food packaging, enzyme stabilization, and wound dressing. In the initial evaluation of the extracts, the antioxidant properties against DPPH, antimicrobial properties against 3-gram-positive bacterial species, 3-gram negative bacterial species, 3-common bacterial species between aquatic and human, and 3-fungal species, and anticancer properties against breast cancer cells were performed. The results proved that the methanol extract has the highest antimicrobial, antifungal, antioxidant, and anticancer properties. After identifying the compounds of prepared methanol extract using GC/MS, polyvinylpyrrolidone nanofibers containing methanol extract of Daphne mucronata were prepared. The structure and characteristics of prepared nanofibers were confirmed and determined using FTIR, TGA, BET, SEM, flexural strength, compressive strength, and hydrophilicity. Synthesized polyvinylpyrrolidone nanofibers containing methanol extract of D. mucronata were subjected to antimicrobial properties on the strains studied in methanol extract of D. mucronata. The antimicrobial properties of synthesized polyvinylpyrrolidone nanofibers containing methanol extract of D. mucronata were compared. The results showed that synthesized polyvinylpyrrolidone nanofibers containing methanol extract of D. mucronata have the potential to introduction bioactive natural synthesis nanoparticles.

Severe efavirenz associated neurotoxicity: A retrospective cohort study.

Background: Efavirenz (EFV) is associated with neuropsychiatric symptoms. Severe neurotoxicity has been reported but the clinical phenotype and risk factors are poorly defined. Objectives: To characterise clinical presentations, risk factors and outcomes to help clinicians recognise severe neurotoxicity earlier. Method: The authors retrospectively identified adults with supratherapeutic EFV concentrations (> 4 mg/L) obtained during routine clinical care in Cape Town, South Africa. Clinical and laboratory data at the time of EFV quantification were extracted from medical records. Logistic regression was performed to identify associations with neuropsychiatric symptoms, and with severe neurotoxicity. Results: Eighty one patients were included; 62 with neuropsychiatric manifestations (most frequently ataxia [n = 20] and psychomotor slowing [n = 24]); and 19 with hepatotoxicity. Overall, 28 (34.6%) were male, 49 (60.5%) had concomitant isoniazid exposure, and median EFV concentration was 12.1 mg/L (interquartile range [IQR]: 6.6-20.0). Neuropsychiatric symptoms were associated with longer duration of EFV therapy, adjusted odds ratio (aOR) 1.3/180-day increment (95% confidence interval [CI]: 1.0-1.7); higher EFV concentrations, aOR 1.2/1 mg/L increase (95% CI: 1.0-1.4) and isoniazid exposure, aOR 8.2 (95% CI: 2.5-26.7). Severe neuropsychiatric symptoms occurred in 47 (75%) patients at a median of 5.9 months (IQR: 2.1-40.8) after EFV initiation. Severe symptoms odds were 1.2-fold higher (95% CI: 1.1-1.4) per 1 mg/L increase in EFV concentration. Symptoms resolved completely within 1 month in 25 (76%) patients with severe neurotoxicity who discontinued EFV. Conclusion: A concentration-effect relationship for severe neurotoxicity exists, which occurred late and resolved in most patients after EFV discontinuation. Contribution: The authors highlighted clinical heterogeneity and morbidity of EFV-associated neurotoxicity.

IL-33 priming and antigenic stimulation synergistically promote the transcription of proinflammatory cytokine and chemokine genes in human skin mast cells.

BACKGROUND: Antigenic stimulation through cross-linking the IgE receptor and epithelial cell-derived cytokine IL-33 are potent stimuli of mast cell (MC) activation. Moreover, IL-33 primes a variety of cell types, including MCs to respond more vigorously to external stimuli. However, target genes induced by the combined IL-33 priming and antigenic stimulation have not been investigated in human skin mast cells (HSMCs) in a genome-wide manner. Furthermore, epigenetic changes induced by the combined IL-33 priming and antigenic stimulation have not been evaluated. RESULTS: We found that IL-33 priming of HSMCs enhanced their capacity to promote transcriptional synergy of the IL1B and CXCL8 genes by 16- and 3-fold, respectively, in response to combined IL-33 and antigen stimulation compared to without IL-33 priming. We identified the target genes in IL-33-primed HSMCs in response to the combined IL-33 and antigenic stimulation using RNA sequencing (RNA-seq). We found that the majority of genes synergistically upregulated in the IL-33-primed HSMCs in response to the combined IL-33 and antigenic stimulation were predominantly proinflammatory cytokine and chemokine genes. Moreover, the combined IL-33 priming and antigenic stimulation increase chromatin accessibility in the synergy target genes but not synergistically. Transcription factor binding motif analysis revealed more binding sites for NF-κB, AP-1, GABPA, and RAP1 in the induced or increased chromatin accessible regions of the synergy target genes. CONCLUSIONS: Our study demonstrates that IL-33 priming greatly potentiates MCs' ability to transcribe proinflammatory cytokine and chemokine genes in response to antigenic stimulation, shining light on how epithelial cell-derived cytokine IL-33 can cause exacerbation of skin MC-mediated allergic inflammation.

Novel through-the-scope suture closure of colonic EMR defects (with video).

BACKGROUND AND AIMS: Large colon polyps removed by EMR can be complicated by delayed bleeding. Prophylactic defect clip closure can reduce post-EMR bleeding. Larger defects can be challenging to close using through-the-scope clips (TTSCs), and proximal defects are difficult to reach using over-the-scope techniques. A novel, through-the-scope suturing (TTSS) device allows direct closure of mucosal defects without scope withdrawal. The goal of this study was to evaluate the rate of delayed bleeding after the closure of large colon polyp EMR sites with TTSS. METHODS: A multicenter retrospective cohort study was performed involving 13 centers. All defect closure by TTSS after EMR of colon polyps ≥2 cm from January 2021 to February 2022 were included. The primary outcome was rate of delayed bleeding. RESULTS: A total of 94 patients (52% female; mean age, 65 years) underwent EMR of predominantly right-sided (n = 62 [66%]) colon polyps (median size, 35 mm; interquartile range, 30-40 mm) followed by defect closure with TTSS during the study period. All defects were successfully closed with TTSS alone (n = 62 [66%]) or with TTSS and TTSCs (n = 32 [34%]), using a median of 1 (interquartile range, 1-1) TTSS system. Delayed bleeding occurred in 3 patients (3.2%), with 2 requiring repeated endoscopic evaluation/treatment (moderate). CONCLUSION: TTSS alone or with TTSCs was effective in achieving complete closure of all post-EMR defects, despite a large lesion size. After TTSS closure with or without adjunctive devices, delayed bleeding was seen in 3.2% of cases. Further prospective studies are needed to validate these findings before wider adoption of TTSS for large polypectomy closure.

miR-155 Is a Positive Regulator of FcεRI-Induced Cyclooxygenase-2 Expression and Cytokine Production in Mast Cells.

MicroRNA-155 (miR-155) has been implicated in IgE-dependent allergic disease including asthma and atopic dermatitis. A few roles for miR-155 have been described in mast cells and some specifically related to IgE receptor signaling, but it is not completely understood. Here, we demonstrate by miRNA seq profiling and quantitative RT-PCR that miR-155 expression is significantly increased in human skin-derived mast cells (SMCs) and mouse bone marrow-derived mast cells (BMMCs) following FcεRI crosslinking with antigen. We demonstrate that FcεRI-induced expression of cyclooxygenase-2 (COX-2) was significantly inhibited in miR-155 knockout (KO) BMMCs whereas arachidonate-5-lipoxygenase (ALOX-5) expression and leukotriene C4 (LTC4) biosynthesis, and degranulation were unaffected. FcεRI-induced cytokine production (TNF, IL-6, and IL-13) from miR-155 KO BMMCs was also significantly diminished. Correspondingly, Akt phosphorylation, but not protein expression, was inhibited in the absence of miR-155 whereas p38 and p42/44 were unaffected. Interesting, lipopolysaccharide (LPS)-induced cytokine production was increased in miR-155 KO BMMCs. Together, these data demonstrate that miR-155 specifically targets the FcεRI-induced prostaglandin and cytokine pathways, but not the leukotriene or degranulation pathways, in mast cells. The data further suggest that miR-155 acts indirectly by targeting a repressor of COX-2 expression and a phosphatase that normally blocks Akt phosphorylation. Overall, this study reveals the role of miR-155 as a positive regulator of mast cell function.

Defective humoral immunity disrupts bile acid homeostasis which promotes inflammatory disease of the small bowel.

Mucosal antibodies maintain gut homeostasis by promoting spatial segregation between host tissues and luminal microbes. Whether and how mucosal antibody responses influence gut health through modulation of microbiota composition is unclear. Here, we use a CD19-/- mouse model of antibody-deficiency to demonstrate that a relationship exists between dysbiosis, defects in bile acid homeostasis, and gluten-sensitive enteropathy of the small intestine. The gluten-sensitive small intestine enteropathy that develops in CD19-/- mice is associated with alterations to luminal bile acid composition in the SI, marked by significant reductions in the abundance of conjugated bile acids. Manipulation of bile acid availability, adoptive transfer of functional B cells, and ablation of bacterial bile salt hydrolase activity all influence the severity of small intestine enteropathy in CD19-/- mice. Collectively, results from our experiments support a model whereby mucosal humoral immune responses limit inflammatory disease of the small bowel by regulating bacterial BA metabolism.

Antibiotics Use and Subsequent Risk of Colorectal Cancer: A Swedish Nationwide Population-Based Study.

BACKGROUND: Antibiotics use may increase colorectal cancer (CRC) risk by altering the gut microbiota, with suggestive evidence reported. Our study aims to investigate antibiotics use in relation to subsequent CRC risk. METHODS: This is a nationwide, population-based study with a matched case-control design (first primary CRC cases and 5 matched, cancer-free controls). Complete-population data, extracted from Swedish national registers for the period 2005-2016, were used to calculate odds ratios and 95% confidence intervals. RESULTS: We included 40 545 CRC cases and 202 720 controls. Using the full dataset, we found a positive association between more frequent antibiotics use and CRC, excluding antibiotics prescribed within 2 years of diagnosis attenuated results toward the null. In site-specific analyses, excluding the 2-year washout, the positive association was confined to the proximal colon (adjusted odds ratio for very high use vs no use = 1.17, 95% confidence interval = 1.05 to 1.31). For rectal cancer, an inverse association, which appears to be driven by women, was observed. Quinolones and sulfonamides and/or trimethoprims were positively associated with proximal colon cancer, whereas a more general inverse association, across antibiotics classes, was observed for rectal cancer. We found no association between methenamine hippurate, a urinary tract antiseptic not affecting the gut microbiota, and CRC risk. CONCLUSIONS: This register-based study covering the entire population of Sweden found a robust association between antibiotics use and higher risk of proximal colon cancer and an inverse association with rectal cancer in women. This study strengthens the evidence from previous investigations and adds important insight into site-specific colorectal carcinogenesis.

Human Skin-Derived Mast Cells Spontaneously Secrete Several Angiogenesis-Related Factors.

Mast cells are classically recognized as cells that cause IgE-mediated allergic reactions. However, their ability to store and secrete vascular endothelial growth factor (VEGF) suggests a role in vascular development and tumorigenesis. The current study sought to determine if other angiogenesis-related factors, in addition to VEGF, were also secreted by human tissue-derived mast cells. Using proteome array analysis and ELISA, we found that human skin-derived mast cells spontaneously secrete CXCL16, DPPIV, Endothelin-1, GM-CSF, IL-8, MCP-1, Pentraxin 3, Serpin E1, Serpin F1, TIMP-1, Thrombospondin-1, and uPA. We identified three groups based on their dependency for stem cell factor (SCF), which is required for mast cell survival: Endothelin-1, GM-CSF, IL-8, MCP-1, and VEGF (dependent); Pentraxin 3, Serpin E1, Serpin F1, TIMP-1, and Thrombospondin-1 (partly dependent); and CXCL16, DPPIV, and uPA (independent). Crosslinking of FcεRI with multivalent antigen enhanced the secretion of GM-CSF, Serpin E1, IL-8, and VEGF, and induced Amphiregulin and MMP-8 expression. Interestingly, FcεRI signals inhibited the spontaneous secretion of CXCL16, Endothelin-1, Serpin F1, Thrombospondin-1, MCP-1 and Pentraxin-3. Furthermore, IL-6, which we previously showed could induce VEGF, significantly enhanced MCP-1 secretion. Overall, this study identified several angiogenesis-related proteins that, in addition to VEGF, are spontaneously secreted at high concentrations from human skin-derived mast cells. These findings provide further evidence supporting an intrinsic role for mast cells in blood vessel formation.

Interleukin-6 potentiates FcεRI-induced PGD2 biosynthesis and induces VEGF from human in situ-matured skin mast cells.

BACKGROUND: Interleukin-6 is a gp130 utilizing cytokine that is consistently associated with allergic diseases like asthma and urticaria in humans where mast cells are known to play a critical role. However, the role of IL-6 in allergic disease in not known. IL-6 was reported to enhance degranulation of in vitro-derived mast cells, but the effect of IL-6 on mediator release from human in situ-matured tissue-isolated mast cells had not been reported. METHODS: Human mature mast cells were isolated and purified from normal skin tissue from different donors. The expression of surface-expressed IL-6 receptors was demonstrated by flow cytometry. The effect of IL-6 on FcεRI-induced degranulation, PGD2 biosynthesis, and cytokine production was determined with ß­hexosaminidase release assay, Western blotting, quantitative real-time PCR, and ELISA. The small molecule inhibitor of STAT-3, C188-9, was used to demonstrate STAT3 dependency. RESULTS: IL-6 significantly potentiated FcεRI-induced PGD2 biosynthesis, but had no effect on degranulation. IL-6 also induced VEGF gene expression and protein secretion, and enhanced FcεRI-induced IL-8 production. Mechanistically, IL-6 enhanced FcεRI-induced COX­2 expression, PGD2 biosynthesis, and VEGF production in a STAT3 dependent manner. CONCLUSION: Here, we demonstrate that IL-6 is a potentiator of FcεRI-induced PGD2 biosynthesis, and can induce or enhance production of pro-angiogenesis factors VEGF and IL-8 from human in situ-matured skin mast cells. GENERAL SIGNIFICANCE: These findings from this study indicate that IL-6 contributes to human allergic disease by enhancing the production of inflammatory PGD2 from tissue-resident mast cells. Moreover, the data suggest a novel role for IL-6 in mast cell-mediated angiogenesis.