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Colon cancer is one of the most common cancer around the world. Exopolysaccharides (EPSs) produced by lactobacilli as potential prebiotics have been found to have an anti-tumor effect. In this study, lyophilized EPSs of four Lactobacillus spp. for their impact on apoptosis in colon cancer cells (HT-29) was evaluated using flow cytometry. The relationship between capability of a lactobacilli-EPS to induce apoptosis and their monosaccharide composition, molecular weight (MW), and linkage type was investigated by HPLC, SEC, and NMR, respectively. Changes in apoptotic-markers were examined by qPCR and Western Blotting. EPSs were capable of inhibiting proliferation in a time-dependent manner and induced apoptosis via increasing the expression of Bax, Caspase 3 and 9 while decreasing Bcl-2 and Survivin. All EPSs contained mannose, glucose, and N-acetylglucosamine with different relative proportions. Some contained arabinose or fructose. MW ranged from 10 2 –10 4 Da with two or three fractions. EPS of L. delbrueckii ssp. bulgaricus B3 having the highest amount of mannose and the lowest amount of glucose, showed the highest apoptosis induction. In conclusion, lactobacilli-EPSs inhibit cell proliferation in HT-29 via apoptosis. Results suggest that a relationship exists between the ability of EPS to induce apoptosis and its mannose and glucose composition.

Surface-initiated reversible addition-fragmentation chain transfer (SI-RAFT) polymerization of N-[3-(dimethylamino)propyl]methacrylamide (DMAPMA) on the silicon wafer was conducted in attempt to create controllable cationic polymer films. The RAFT agent-immobilized substrate was prepared by the silanization of hydroxyl groups on silicon wafer with 3-aminopropylthriethoxysilane (APTS) and by the amide reaction of amine groups of APTS with ester groups of 4-cyano-4-((thiobenzoyl) sulfanyl) pentanoic succinimide ester (CPSE); followed by the RAFT polymerization of DMAPMA using a ''free'' RAFT agent, that is, 4-cyanopentanoic acid dithiobenzoate (CPAD) and an initiator, that is, 4,4 0 -azobis-4-cyanopentanoic acid (CPA). The formation of homogeneous tethered poly(N-[3-(dimethylamino)propyl]methacrylamide) [poly(DMAPMA)] brushes, whose thick-ness can be tuned by reaction time varying, is evidenced by using the combination of grazing angle attenuated total reflectance-Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, atomic force microscopy, and water contactangle measurements. The calculation of grafting parameters from the number-average molecular weight, M n (g/mol) and ellipsometric thickness, h (nm) values indicated the synthesis of densely grafted poly(DMAPMA) films and allowed us to predict a polymerization time for forming a ''brush-like'' conformation for the chains.

Background Coronavirus disease 2019 (COVID-19) continues to cause major mortality and morbidity worldwide even after a year of its emergence. In its early days, hypertension, diabetes, and cardiovascular diseases were noted as poor prognostic factors, while obesity gained attention at a later stage. In the present study, unfavorable clinical outcomes (transfer to the intensive care unit, invasive mechanical ventilation, and mortality) were investigated in obese patients with COVID-19. Materials and Methods In this retrospective study we analyzed patients with positive polymerase chain reaction test in tertiary care hospital between March-May 2020. They were divided into 3 groups according to body mass index (BMI) as normal, overweight, and obese (BMI: 18.5 - 24.99 kg/m 2 , 25 - 29.99 kg/m 2 , and ≥ 30 kg/m 2 , respectively). We compared clinical features and laboratory findings of these groups and recorded adverse clinical outcomes. Multivariate logistic analysis was performed for unfavorable outcomes. Results There were 99 patients (35%), 116 (41%), and 69 patients (24%) in the normal-weight, overweight, and obese group, respectively. Among all patients, 52 (18%) patients were transferred to the intensive care unit (ICU), 30 (11%) patients received invasive mechanical ventilation (IMV), and 22 patients (8%) died. Obese patients had minimum 1 more comorbidity than normal BMI patients (73% vs. 50%, P = 0.002), and a longer median (interquartile range [IQR]) duration of hospitalization (8 [5 - 12] vs. 6 [5 - 9]) days, P = 0.006). Obese participants had higher concentrations of serum C-reactive protein, procalcitonin, ferritin than non-obese patients ( P <0.05 in all). In a multivariate analysis, obesity was associated with ICU admission (adjusted odds ratio [aOR]: 2.99, 95% confidence interval [CI]: 1.26 - 7.04, P = 0.012). Moreover, IMV requirement was associated with obesity (aOR: 8.73, 95% CI: 2.44 - 31.20, P = 0.001). Mortality occurred in 16%, 9%, and 1% of the obese group, overweight group, and normal-weight group, respectively (Chi-square trend analysis, P = 0.002). Conclusion Obesity is a risk factor for adverse outcomes and caused increased mortality, hence requiring close follow-up.

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