1,403 research outputs found

    Ex vivo and In vivo Evaluation of Chitosan Coated Nanostructured Lipid Carriers for Ocular Delivery of Acyclovir

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    Background: Herpes keratitis is the most common infectious cause of blindness in the developed world. It may be treated by acyclovir (ACV), however this antiviral drug is poorly soluble with low ocular bioavailability requiring high and frequent dosing. Nanostructured lipid carriers (NLCs) were investigated to improve the ocular bioavailability of ACV by enhancing corneal penetration as well as prolonging the exposure of infected cells to the antiviral agent. Methods: Cell uptake studies, ex vivo tolerance and cell uptake efficacy as well as in vivo corneal permeation of the developed lipid based formulations were investigated. NLCs were fabricated by the hot microemulsion technique and coated with 0.5% w/v chitosan. NLCs were capable of increasing the cell uptake of encapsulated fluorescein and ACV as examined by fluorescence microscopy and high performance liquid chromatography (HPLC) respectively. Results: When entrapped in NLCs, the antiviral efficacy of ACV was increased by 3.5 fold after 24 hrs of exposure. The in vivo corneal permeation of the formulation was studied on Albino rabbits with NLCs capable of increasing the corneal bioavailability by 4.5 fold when compared to a commercially available ACV ophthalmic ointment. Conclusion: NLCs enhanced the ocular bioavailability and antiviral properties of ACV through cell internalisation, sustained release, and increased corneal permeation

    Promising New Inhibitors of Tyrosyl-DNA Phosphodiesterase I (Tdp 1) Combining 4-Arylcoumarin and Monoterpenoid Moieties as Components of Complex Antitumor Therapy

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    Tyrosyl-DNA phosphodiesterase 1 (Tdp1) is an important DNA repair enzyme in humans, and a current and promising inhibition target for the development of new chemosensitizing agents due to its ability to remove DNA damage caused by topoisomerase 1 (Top1) poisons such as topotecan and irinotecan. Herein, we report our work on the synthesis and characterization of new Tdp1 inhibitors that combine the arylcoumarin (neoflavonoid) and monoterpenoid moieties. Our results showed that they are potent Tdp1 inhibitors with IC50 values in the submicromolar range. In vivo experiments with mice revealed that compound 3ba (IC50 0.62 µM) induced a significant increase in the antitumor effect of topotecan on the Krebs-2 ascites tumor model. Our results further strengthen the argument that Tdp1 is a druggable target with the potential to be developed into a clinically-potent adjunct therapy in conjunction with Top1 poisons

    Enteral lactoferrin to prevent infection for very preterm infants: the ELFIN RCT.

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    BACKGROUND: Infections acquired in hospital are an important cause of morbidity and mortality in very preterm infants. Several small trials have suggested that supplementing the enteral diet of very preterm infants with lactoferrin, an antimicrobial protein processed from cow's milk, prevents infections and associated complications. OBJECTIVE: To determine whether or not enteral supplementation with bovine lactoferrin (The Tatua Cooperative Dairy Company Ltd, Morrinsville, New Zealand) reduces the risk of late-onset infection (acquired > 72 hours after birth) and other morbidity and mortality in very preterm infants. DESIGN: Randomised, placebo-controlled, parallel-group trial. Randomisation was via a web-based portal and used an algorithm that minimised for recruitment site, weeks of gestation, sex and single versus multiple births. SETTING: UK neonatal units between May 2014 and September 2017. PARTICIPANTS: Infants born at < 32 weeks' gestation and aged < 72 hours at trial enrolment. INTERVENTIONS: Eligible infants were allocated individually (1 : 1 ratio) to receive enteral bovine lactoferrin (150 mg/kg/day; maximum 300 mg/day) or sucrose (British Sugar, Peterborough, UK) placebo (same dose) once daily from trial entry until a postmenstrual age of 34 weeks. Parents, caregivers and outcome assessors were unaware of group assignment. OUTCOMES: Primary outcome - microbiologically confirmed or clinically suspected late-onset infection. Secondary outcomes - microbiologically confirmed infection; all-cause mortality; severe necrotising enterocolitis (NEC); retinopathy of prematurity (ROP); bronchopulmonary dysplasia (BPD); a composite of infection, NEC, ROP, BPD and mortality; days of receipt of antimicrobials until 34 weeks' postmenstrual age; length of stay in hospital; and length of stay in intensive care, high-dependency and special-care settings. RESULTS: Of 2203 enrolled infants, primary outcome data were available for 2182 infants (99%). In the intervention group, 316 out of 1093 (28.9%) infants acquired a late-onset infection versus 334 out of 1089 (30.7%) infants in the control group [adjusted risk ratio (RR) 0.95, 95% confidence interval (CI) 0.86 to 1.04]. There were no significant differences in any secondary outcomes: microbiologically confirmed infection (RR 1.05, 99% CI 0.87 to 1.26), mortality (RR 1.05, 99% CI 0.66 to 1.68), NEC (RR 1.13, 99% CI 0.68 to 1.89), ROP (RR 0.89, 99% CI 0.62 to 1.28), BPD (RR 1.01, 99% CI 0.90 to 1.13), or a composite of infection, NEC, ROP, BPD and mortality (RR 1.01, 99% CI 0.94 to 1.08). There were no differences in the number of days of receipt of antimicrobials, length of stay in hospital, or length of stay in intensive care, high-dependency or special-care settings. There were 16 reports of serious adverse events for infants in the lactoferrin group and 10 for infants in the sucrose group. CONCLUSIONS: Enteral supplementation with bovine lactoferrin does not reduce the incidence of infection, mortality or other morbidity in very preterm infants. FUTURE WORK: Increase the precision of the estimates of effect on rarer secondary outcomes by combining the data in a meta-analysis with data from other trials. A mechanistic study is being conducted in a subgroup of trial participants to explore whether or not lactoferrin supplementation affects the intestinal microbiome and metabolite profile of very preterm infants. TRIAL REGISTRATION: Current Controlled Trials ISRCTN88261002. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 22, No. 74. See the NIHR Journals Library website for further project information. This trial was also sponsored by the University of Oxford, Oxford, UK. The funder provided advice and support and monitored study progress but did not have a role in study design or data collection, analysis and interpretation

    STK295900, a Dual Inhibitor of Topoisomerase 1 and 2, Induces G<inf>2</inf> Arrest in the Absence of DNA Damage

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    STK295900, a small synthetic molecule belonging to a class of symmetric bibenzimidazoles, exhibits antiproliferative activity against various human cancer cell lines from different origins. Examining the effect of STK295900 in HeLa cells indicates that it induces G2 phase arrest without invoking DNA damage. Further analysis shows that STK295900 inhibits DNA relaxation that is mediated by topoisomerase 1 (Top 1) and topoisomerase 2 (Top 2) in vitro. In addition, STK295900 also exhibits protective effect against DNA damage induced by camptothecin. However, STK295900 does not affect etoposide-induced DNA damage. Moreover, STK295900 preferentially exerts cytotoxic effect on cancer cell lines while camptothecin, etoposide, and Hoechst 33342 affected both cancer and normal cells. Therefore, STK295900 has a potential to be developed as an anticancer chemotherapeutic agent. © 2013 Kim et al

    Phase III study of 5FU, etoposide and leucovorin (FELV) compared to epirubicin, cisplatin and 5FU (ECF) in previously untreated patients with advanced biliary cancer

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    The purpose of this study was to determine whether epirubicin, cisplatin and infused 5FU (ECF) improves overall survival (OS) compared to 5FU, etoposide and leucovorin (FELV) in patients with previously untreated advanced biliary cancer in a prospective randomised study. Patients were randomly assigned to receive epirubicin, cisplatin and infused 5FU ECF or bolus 5FU etoposide and leucovorin (FELV). The primary end point was OS with secondary end points of objective response rate (ORR), failure-free survival (FFS), quality of life (QOL) and toxicity. In all, 54 patients were recruited with 27 randomly assigned to each arm. The median OS for ECF was 9.02 months (95% confidence interval (CI): 6.46–11.51) and FELV 12.03 months (95% CI: 9.3–14.7), P=0.2059. Objective response rates were similar for both arms: ECF 19.2% (95% CI: 6.55–39.3); FELV 15% (95% CI: 3.2–37.9), P=0.72. There was significantly increased grade 3/4 neutropenia with FELV vs ECF (53.8 vs 29.5%, respectively, P=0.020). Symptom resolution was impressive for both regimens. This is the largest reported randomised study to date in this setting. ECF did not improve OS compared to FELV, but was associated with less acute toxicity. These data suggest that chemotherapy can prolong OS and achieve good symptomatic relief in advanced biliary cancer

    Global prospective case series of ERCPs using a single-use duodenoscope

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    Background The first commercialized single-use duodenoscope was cleared by the US Food and Drug Administration in December 2019. Data regarding endoscopic retrograde cholangiopancreatography (ERCP) using a single-use duodenoscope are needed on a broader range of cases conducted by endoscopists with varying levels of experience in a wide range of geographic areas. Methods 61 endoscopists at 22 academic centers in 11 countries performed ERCP procedures in adult patients aged ? 18. Outcomes included ERCP completion for the intended indication, rate of crossover to a reusable endoscope, device performance ratings, and serious adverse events (SAEs). Results Among 551 patients, 236 (42.8 %) were aged &gt;65, 281 (51.0 %) were men, and 256 (46.5 %) had their procedure as an inpatient. ERCPs included 196 (35.6 %) with American Society for Gastrointestinal Endoscopy complexity of grades 3 4. A total of 529 ERCPs (96.0 %) were completed: 503 (91.3 %) using only the single-use duodenoscope, and 26 (4.7 %) with crossover to a reusable endoscope. There were 22 ERCPs (4.0 %) that were not completed, of which 11 (2.0 %) included a crossover and 11 (2.0 %) were aborted cases (no crossover). Median ERCP completion time was 24.0 minutes. Median overall satisfaction with the single-use duodenoscope was 8.0 (scale of 1 to 10 [best]). SAEs were reported in 43 patients (7.8 %), including 17 (3.1 %) who developed post-ERCP pancreatitis. Conclusions In academic medical centers over a wide geographic distribution, endoscopists with varying levels of experience using the first marketed single-use duodenoscope had good ERCP procedural success and reported high performance ratings for this device.</p

    Lactic acid production from lime-treated wheat straw by Bacillus coagulans: neutralization of acid by fed-batch addition of alkaline substrate

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    Conventional processes for lignocellulose-to-organic acid conversion requires pretreatment, enzymatic hydrolysis, and microbial fermentation. In this study, lime-treated wheat straw was hydrolyzed and fermented simultaneously to lactic acid by an enzyme preparation and Bacillus coagulans DSM 2314. Decrease in pH because of lactic acid formation was partially adjusted by automatic addition of the alkaline substrate. After 55 h of incubation, the polymeric glucan, xylan, and arabinan present in the lime-treated straw were hydrolyzed for 55%, 75%, and 80%, respectively. Lactic acid (40.7 g/l) indicated a fermentation efficiency of 81% and a chiral l(+)-lactic acid purity of 97.2%. In total, 711 g lactic acid was produced out of 2,706 g lime-treated straw, representing 43% of the overall theoretical maximum yield. Approximately half of the lactic acid produced was neutralized by fed-batch feeding of lime-treated straw, whereas the remaining half was neutralized during the batch phase with a Ca(OH)2 suspension. Of the lime added during the pretreatment of straw, 61% was used for the neutralization of lactic acid. This is the first demonstration of a process having a combined alkaline pretreatment of lignocellulosic biomass and pH control in fermentation resulting in a significant saving of lime consumption and avoiding the necessity to recycle lime
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