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The impact of zwitterionic graphene oxide (GO-Arg) nanostructures into polyethersulfone (PES) membranes was studied, aiming to perform mixed matrix membranes (MMMs) with combined antibacterial and antifouling properties. For this purpose, 0.25, 0.50, and 1.0 wt% of GO-Arg were incorporated through the phase inversion method. The chemical composition reveals that the electrostatic interactions of PES, polyvinylpyrrolidone, and GO-Arg occur by enhancing the C--H/N-H vibrations associated with the intrinsic MMMs and their combined antibacterial and antifouling performance. Well-defined finger-like morphology was observed, performing the pore distribution and the finger-cavity inclination induced by the electrostatic charge of GO-Arg. As a result, GO-Arg MMM's hydrophobic properties decreased from 77.8[degrees] to 52.3[degrees], inducing a partially hydrophilic surface and improved water flux. The isoelectric point of nanostructured membranes slightly changes by the charge modulation produced by zwitterionic GO-Arg. The antibacterial activity against Gram (--) Escherichia coli was improved, closing the complete bacterial inhibition after 24 h. As a result, antifouling performance was improved, avoiding bacterial adhesion into the membrane surface and the possibility of promoting biofilm formation. Our results demonstrate that zwitterionic nanomaterials in MMMs perform the multifunctional capacity of materials, emerging as an effective alternative with potential application in wastewater treatment. Highlights * The incorporation of zwitterionic GO-Arg improves the mechanical properties of MMMs. * GO-Arg-enhanced well-defined porous finger-like morphology in MMMs. * GO-Arg improves the antibacterial/antifouling performance of PES-based MMMs. KEYWORDS antibacterial, antifouling, graphene oxide, nanostructured membranes, polyethersulfone membranes, zwitterionic, 1 | INTRODUCTION The constant increase in population and the exponential development of the industrial sector worldwide have severely affected the aquifers, resulting in the spread of toxic agents, pollutants, [...]

This study focuses on the surface modification of substrates using a poly (N,N-dimethyl-N-(ethoxycarbonylmethyl)-N-[2'-(methacryloyloxy) ethyl]-ammonium chloride-co-3-(trimethoxysilyl)propylmethacrylate) P(CBMAE-co-TMSPMA) and ethyl orthosilicate (TEOS). By covalently bonding the SiOH pendant of the copolymer with hydroxyl residues on the material's surface, a stable polymer coating is formed. The properties of P(CBMAE-co-TMSPMA) coatings were evaluated using Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), scanning electron microscope (SEM), and contact angle (CA) meter. The addition of TEOS allows for the regulation of surface roughness. With the increase of TEOS content, the contact angle of underwater oil first increased and then decreased. The water contact angles were 8[degrees], the underwater superoleophobic contact angle reached 168[degrees], and the number of adherent platelets and Escherichia coli were significantly reduced to 7.5% and 5% on the surface of the coating, respectively. After undergoing simultaneous hydrolysis, the superoleophobic contact angle of P(CBMAE-co-TMSPMA)/Si[O.sub.2] coating further increased to 174[degrees]. These interesting and robust properties make them promising candidates for biomedical applications. Highlights * The underwater superoleophobic coating (contact angles of 174[degrees]). * The P(CBMAE-co-TMSPMA)/Si[O.sub.2] coating with excellent resistance to oil adhesion. * Solve the hydroxyl residue problem. * The coating resistance to E. coli and platelet adhesion. KEYWORDS anti-biofouling, Polyzwitterionic carboxylate, robust surface, underwater superoleophobic coating, 1 | INTRODUCTION Anti-fouling and anti-adhesion properties are important challenges in several disciplines, such as ship antifouling, marine engineering, (1,2) biomedical materials, (3,4) fluid transport, (5) water purification systems, food [...]

Background Enteric infections are hypothesized to be associated with intussusception in children. A small increase in intussusception following rotavirus vaccination has been seen in some settings. We conducted post-marketing surveillance for intussusception following rotavirus vaccine, Rotavac introduction in India and evaluated association of intussusception with enteric pathogens. Methods In a case-control study nested within a large sentinel hospital-based surveillance program in India, stool samples from 272 children aged less than 2 years admitted for intussusception and 272 age-, gender- and location-matched controls were evaluated with Taqman array card based molecular assays to detect enteric viruses, bacterial enteropathogens and parasites. Matched case-control analysis with conditional logistic regression evaluated association of enteropathogens with intussusception. Population attributable fractions (PAF) were calculated for enteropathogens significantly associated with intussusception. Results The most prevalent enteropathogens in cases and controls were enteroaggregative Escherichia coli, adenovirus 40/41, adenovirus C serotypes and enteroviruses. Children with intussusception were more likely to harbor adenovirus C serotypes (adjusted odds-ratio (aOR) = 1.74; 95% confidence interval (CI) 1.06-2.87) and enteroviruses (aOR = 1.77; 95% CI 1.05-2.97) than controls. Rotavirus was not associated with increased intussusception risk. Adenovirus C (PAF = 16.9%; 95% CI 4.7% - 27.6%) and enteroviruses (PAF = 14.7%; 95% CI 4.2% - 24.1%) had the highest population attributable fraction for intussusception. Conclusion Adenovirus C serotypes and enteroviruses were significantly associated with intussusception in Indian children. Rotavirus was not associated with risk of intussusception. Keywords: Intussusception, Case-control, Adenovirus, Viral pathogens, PAF, Author(s): Ira Praharaj[sup.1,2], Samarasimha Nusi Reddy[sup.1], Nayana Prabhakaran Nair[sup.1], Jacqueline Elizabeth Tate[sup.3], Sidhartha Giri[sup.1,2], Varunkumar Thiyagarajan[sup.1], Venkata Raghava Mohan[sup.4], Rajendiran Revathi[sup.1], Kalaivanan Maheshwari[sup.1], Priya Hemavathy[sup.1], Nirmal Kumar[sup.1], Mohan Digambar Gupte[sup.5], [...]

Background Recently, the oral oncobacterium Fusobacterium nucleatum (F. nucleatum), has been linked with ulcerative colitis (UC). Here, we aim to investigate whether Fecal Microbiota Transplantation (FMT) can alleviate UC by restoring gut microbiota and eliminating oral-derived F. nucleatum and virulence factor fadA. Method C57BL/6J mice were randomly divided into a healthy control group (HC), Dextran Sulfate Sodium group (DSS), oral inoculation group (OR), upper FMT group (UFMT), and lower FMT group (LFMT). Disease activity index, body weight, survival rate, and histopathological scores were used to measure the severity of colitis. The function of the intestinal mucosal barrier was evaluated by performing immunohistochemical staining of the tight junction protein Occludin. Real-time PCR was used to assess the relative abundance of the nusG gene and the virulence gene fadA. Cytokine levels were detected by ELISA. Full-length sequencing of 16S rRNA was used to analyze the changes and composition of gut microbiota. Findings Oral incubation of F. nucleatum further exacerbated the severity of colitis and gut dysbiosis. Peptostreptococcaceae, Enterococcaceae, and Escherichia coli were significantly enriched in OR mice. However, LFMT mice showed an obvious decrease in disease activity and were more effective in restoring gut microbiota and eliminating F. nucleatum than UFMT mice. Bacteroidota, Lachnospiraceae, and Prevotellaceae were mainly enriched bacteria in LFMT mice. In addition, Genera such as Lactobacillus, Allobaculum, and Bacteroidales were found negative correlation with TNF-[alpha], IL-1[beta], and IL-6. Genera like Romboutsia, Escherichia Shigella, Enterococcus, and Clostridium were found positively correlated with TNF-[alpha], IL-1[beta], and IL-6. Conclusions Oral incubation of F. nucleatum further exacerbates the severity and dysbiosis in DSS-induced colitis mice. Besides, lower tract FMT can ameliorate colitis by restoring the gut microbiota diversity and eliminating F. nucleatum and virulence factor fadA. Keywords: Ulcerative colitis, Oral pathogenic bacteria, DSS-induced colitis, Fecal microbiota transplantation, 16S rRNA sequencing, Author(s): Dong-Hao Li[sup.1], Zong-Wei Li[sup.1], Qi Sun[sup.1], Lei Wang[sup.1] and Shou-Bin Ning[sup.1] Introduction Ulcerative colitis (UC) is a chronic, multifactorial, and non-specific inflammatory condition of the colon and rectum, with [...]

Background Gut dysbiosis contributes to the high risk of bloodstream infection (BSI) among premature infants. Most prior studies of the premature infant gut microbiota were conducted in Western countries and prior to development of current tools for strain-resolved analysis. Methods We performed metagenomic sequencing of weekly fecal samples from 75 premature infants at a single hospital in Singapore. We evaluated associations between clinical factors and gut microbiota composition using PERMANOVA and mixed effects linear regression. We used inStrain to perform strain-level analyses evaluating for gut colonization by BSI-causing strains. Results Median (interquartile range) gestation was 27 (25, 29) weeks, and 63% of infants were born via Cesarean section. Antibiotic exposures (PERMANOVA; R.sup.2 = 0.017, p = 0.001) and postnatal age (R.sup.2 = 0.015, p = 0.001) accounted for the largest amount of variability in gut microbiota composition. Increasing postnatal age was associated with higher relative abundances of several common pathogens (Enterococcus faecalis: p < 0.0001; Escherichia coli: p < 0.0001; Klebsiella aerogenes: p < 0.0001; Klebsiella pneumoniae: p < 0.0001). Antibiotic exposures were generally associated with lower relative abundances of both frequently beneficial bacteria (e.g., Bifidobacterium species) and common enteric pathogens (e.g., Enterobacter, Klebsiella species). We identified strains identical to the blood culture isolate in fecal samples from 12 of 16 (75%) infants who developed BSI, including all infections caused by typical enteric bacteria. Conclusions Antibiotic exposures were the dominant modifiable factor affecting gut microbiota composition in a large cohort of premature infants from South-East Asia. Strain-resolved analyses indicate that the gut is an important reservoir for organisms causing BSI among premature infants. Keywords: Preterm neonates, Early-onset sepsis, Late-onset sepsis, Intestinal microbiome, inStrain, Author(s): Sarah M. Heston[sup.1], Charis Shu En Lim[sup.2], Chengsi Ong[sup.2,3,4], Mei Chien Chua[sup.2,3], Matthew S. Kelly[sup.1] and Kee Thai Yeo[sup.2,3] Background Sepsis remains a major cause of mortality and morbidity [...]

Background Formyl peptide receptor 2 (Fpr2) plays a crucial role in colon homeostasis and microbiota balance. Commensal E. coli is known to promote the regeneration of damaged colon epithelial cells. The aim of the study was to investigate the connection between E. coli and Fpr2 in the recovery of colon epithelial cells. Results The deficiency of Fpr2 was associated with impaired integrity of the colon mucosa and an imbalance of microbiota, characterized by the enrichment of Proteobacteria in the colon. Two serotypes of E. coli, O22:H8 and O91:H21, were identified in the mouse colon through complete genome sequencing. E. coli O22:H8 was found to be prevalent in the gut of mice and exhibited lower virulence compared to O91:H21. Germ-free (GF) mice that were pre-orally inoculated with E. coli O22:H8 showed reduced susceptibility to chemically induced colitis, increased proliferation of epithelial cells, and improved mouse survival. Following infection with E. coli O22:H8, the expression of Fpr2 in colon epithelial cells was upregulated, and the products derived from E. coli O22:H8 induced migration and proliferation of colon epithelial cells through Fpr2. Fpr2 deficiency increased susceptibility to chemically induced colitis, delayed the repair of damaged colon epithelial cells, and heightened inflammatory responses. Additionally, the population of E. coli was observed to increase in the colons of Fpr2.sup.-/- mice with colitis. Conclusion Commensal E. coli O22:H8 stimulated the upregulation of Fpr2 expression in colon epithelial cells, and the products from E. coli induced migration and proliferation of colon epithelial cells through Fpr2. Fpr2 deficiency led to an increased E. coli population in the colon and delayed recovery of damaged colon epithelial cells in mice with colitis. Therefore, Fpr2 is essential for the effects of commensal E. coli on colon epithelial cell recovery. Keywords: Commensal E. coli, Fpr2.sup.-/- mice, Germ-free mice, Colitis, Regeneration, Author(s): Keqiang Chen[sup.1], John McCulloch[sup.2], Rodrigo Das Neves[sup.2], Gisele Roderigues[sup.1], Wang-Ting Hsieh[sup.3], Wanghua Gong[sup.4], Teizo Yoshimura[sup.5], Jiaqiang Huang[sup.1,6], Colm O'hUigin[sup.2], Simone Difilippantonio[sup.7], Matthew McCollum[sup.7], Georgette Jones[sup.7], Scott K. Durum[sup.1], Giorgio [...]