Fabrication of anisotropic polymer colloid particles

The fabrication of complex colloidal particles with anisotropic "patchy" e.g. Januslike, morphology will be studied. Known approaches towards "Janus particles" focus mostly on the micron-sized domain, with common fabrication routes based on monolayer modification or microfluidic production (restricts scale-up). We operate in the submicron regime (typically 100-500 nm) and use scalable emulsion polymerization strategies, in combination with entropic phase separation of swollen cross-linked latex particles and living radical polymerization, i.e. SET-LRP, to prepare our "patchy" amphiphilic particles. In this research, various Cross-linked densities (typically from 1 - 8wt%) poly(styrene) latexes (typically 100-500 nm) functionalized with tert-bromine functional groups, by batch or shot addition of (2-methacryloxyethyl -2- bromoisobutyrate) made via soap-free emulsion polymerization used as the precursor particles. Two synthetic pathways were investigated to make the targeted hairy Janus Particles. Approach one: in which we carried out the domain formation step prior to the fabrication of the polymer brushes, We found out that the effective synthetic way to make Janus hairy dumbbell particles in a reproducible manner is to start the synthesis with light cross-linked density of (1.9 to 3.0 wt% DVB) precursor poly(styrene) latex particles (150-250 nm diameter) made by shot addition method. The direct entropic phase separation from these latex particles leads to the formation of only one new domain with dumbbell shape morphology, when the swelling ratio used between monomer and latex is between 2.0 and 4.0, and with low DVB concentration in the swelling monomer (between 0.15-1.0wt%) using AIBN as initiator. Formation of hydrophilic polymer brushes by SET-LRP resulted in targeted hairy Janus particles with sub-micrometer diameter, in a reproducible manner. The length of the polymer brushes can be controlled by addition of water soluble ATRP initiator to produce shorter polymer brushes. The rate of SET-LRP was ultrafast and the rate can be reduced by addition of deactivator CuBr2. The second approach: water-soluble polymer brushes were grafted onto the surface of latex particles by SET-LRP. These “hairy” cross-linked colloids were swollen with additional monomers and initiator. Elevation of temperature causes entropic phase separation inducing new domains, which were polymerized. This approach leads to mainly popcorn and raspberry particles with some limited cases that are able to make hairy Janus Particles with non reproducible manner. The obtained complex particles show some interesting application such as a stabilization agent for Carbon Nanotubes (CNTs) in aqueous medium, Pickering emulsion stabilizer, and they self assembled upon addition of dilute electrolyte solution.EThOS - Electronic Theses Online ServiceSharikah al-Saʻūdīyah lil-Ṣināʻāt al-AsāsīyahGBUnited Kingdo

Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study

Background Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide.Methods A multimethods analysis was performed as part of the GlobalSurg 3 study-a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital.Findings Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3.85 [95% CI 2.58-5.75]; p<0.0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63.0% vs 82.7%; OR 0.35 [0.23-0.53]; p<0.0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer.Interpretation Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised

Fabrication of anisotropic polymer colloid particles

The fabrication of complex colloidal particles with anisotropic "patchy" e.g. Januslike, morphology will be studied. Known approaches towards "Janus particles" focus mostly on the micron-sized domain, with common fabrication routes based on monolayer modification or microfluidic production (restricts scale-up). We operate in the submicron regime (typically 100-500 nm) and use scalable emulsion polymerization strategies, in combination with entropic phase separation of swollen cross-linked latex particles and living radical polymerization, i.e. SET-LRP, to prepare our "patchy" amphiphilic particles. In this research, various Cross-linked densities (typically from 1 - 8wt%) poly(styrene) latexes (typically 100-500 nm) functionalized with tert-bromine functional groups, by batch or shot addition of (2-methacryloxyethyl -2- bromoisobutyrate) made via soap-free emulsion polymerization used as the precursor particles. Two synthetic pathways were investigated to make the targeted hairy Janus Particles. Approach one: in which we carried out the domain formation step prior to the fabrication of the polymer brushes, We found out that the effective synthetic way to make Janus hairy dumbbell particles in a reproducible manner is to start the synthesis with light cross-linked density of (1.9 to 3.0 wt% DVB) precursor poly(styrene) latex particles (150-250 nm diameter) made by shot addition method. The direct entropic phase separation from these latex particles leads to the formation of only one new domain with dumbbell shape morphology, when the swelling ratio used between monomer and latex is between 2.0 and 4.0, and with low DVB concentration in the swelling monomer (between 0.15-1.0wt%) using AIBN as initiator. Formation of hydrophilic polymer brushes by SET-LRP resulted in targeted hairy Janus particles with sub-micrometer diameter, in a reproducible manner. The length of the polymer brushes can be controlled by addition of water soluble ATRP initiator to produce shorter polymer brushes. The rate of SET-LRP was ultrafast and the rate can be reduced by addition of deactivator CuBr2. The second approach: water-soluble polymer brushes were grafted onto the surface of latex particles by SET-LRP. These “hairy” cross-linked colloids were swollen with additional monomers and initiator. Elevation of temperature causes entropic phase separation inducing new domains, which were polymerized. This approach leads to mainly popcorn and raspberry particles with some limited cases that are able to make hairy Janus Particles with non reproducible manner. The obtained complex particles show some interesting application such as a stabilization agent for Carbon Nanotubes (CNTs) in aqueous medium, Pickering emulsion stabilizer, and they self assembled upon addition of dilute electrolyte solution

Kvalitet av generika

Bakgrunn: Forskning har vist at det er betydelig skepsis i befolkningen til generiske legemidler, selv om disse per definisjon er bioekvivalente. Dette har også blitt vist i flere bioekvivalensstudier. Det rapporteres bivirkninger som er knyttet til generisk bytte, men det er ikke nok informasjon i disse bivirkningsmeldingene for å fastslå om disse bivirkninger skyldes kvaliteten av legemidler eller generisk bytte. Hensikt: Hensikten med denne studien var å studere om den objektive kvaliteten til generiske legemidler er annerledes enn for originalproduktet og eventuelt om disse forskjellene kan forklare noen av de meldte bivirkningene og pasienters opplevde svakheter ved generiske legemidler. Metode: Fem virkestoffer ble studert ved å bruke tilgjengelige databaser ved Statens legemiddelverk. Det ble sett på fem ulike parametere for å se på kvaliteten av generiske legemidler. Det ble valgt ut kvalitetsparametere som lett kunne forklare de observerte problemene knyttet til generisk bytte Innsamling av materiell fra disse databasene ble gjort i perioden fra og med august-13 til og med mai-14. Resultater: Resultatene viste at grensene for hvert enkelt produkt både for original og generika var forskjellig, men at det var små forskjeller mellom produktene. Resultatene for bioekvivalens viste at det bare var Cmax verdien som var utenfor de angitte grensene ved to av tilfellene. Alle resultater for dosevariasjon var innenfor grensen på AV 15, men enkelte produsenter hadde høye resultater på 10 og 15. I tillegg viser resultatene for urenheter at enkelte urenheter for kjente og ukjente urenheter ligger utenfor grensen som er angitt i retningslinjer for urenhter, men samtidig er alle urenheter er innenfor de grensene som er angitt av produsenten selv. Disse urenhetene har i tillegg blitt godkjent av legemiddelmyndighetene. Konklusjon: Selv om det ble funnet små forskjeller i den objektive kvaliteten på de undersøkte generiske legemidler sammenlignet med originalpreparater og med hverandre, er ikke forskjellene tilstrekkelig store til å konkludere om det virkelig er forskjell mellom originalprodukt og generiske legemidler. Derfor er det ikke mulig å si at disse bekymringer for bivirkninger kan knyttes til målbare forskjeller mellom preparatene for disse fem virkestoffer. De rapporterte bivirkningene skyldes da sannsynligvis ikke dårlig kvalitet av generika men heller andre ting som for eksempel pasient usikkerhet. Dårlig kvalitet og ubehag knyttet til generika er en problemstilling som mange er opptatt av, både blant pasienter og helsepersonell. Med flere studier kan det kanskje etterhvert konkluderes om det er virkelig forskjell mellom originalproduktet og generika

Protective Effect of Ginger Extract Against Cisplatin-Induced Hepatotoxicity and Cardiotoxicity in Rats.

The protective effect of ginger extract against cisplatin-induced hepatotoxicity and cardiotoxicity was evaluated in 30 albino white rats(weighing 200-300 gm ) classified into 5groups (6 rats per each group). The rats were treated with 0.5g/kg/day or         1g/kg/day ginger extract orally 5 successive days before and 5 successive days after induction of toxicity with intraperitoneal (IP) injection of (10mg/kg ) cisplatin, resulted in a significant reduction in the levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT) , total serum  billirubin(TSB) , lactate dehydrogenase (LDH) and creatine kinase(CK) enzymes in comparison with the cisplatin treated animals; ginger extract also improves the histological changes produced by cisplatin in the liver cells and cardiac muscle fiber cells  in comparison with the control .  It is  concluded that , ginger extract when used concomitantly with cisplatin protects the liver and heart against the toxicity induced by this cytotoxic drug.                                         Key wards :Ginger, Cisplatin,Oxidative Stress