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Potential Carriers (potential + carrier)
Selected AbstractsSelf-Assembling Peptide as a Potential Carrier for Hydrophobic Anticancer Drug Ellipticine: Complexation, Release and In Vitro DeliveryADVANCED FUNCTIONAL MATERIALS, Issue 1 2009Shan Yu Fung Abstract The self-assembling peptide EAK16-II is capable of stabilizing hydrophobic compounds to form microcrystal suspensions in aqueous solution. Here, the ability of this peptide to stabilize the hydrophobic anticancer agent ellipticine is investigated. The formation of peptide-ellipticine suspensions is monitored with time until equilibrium is reached. The equilibration time is found to be dependent on the peptide concentration. When the peptide concentration is close to its critical aggregation concentration, the equilibration time is minimal at 5,h. With different combinations of EAK16-II and ellipticine concentrations, two molecular states (protonated or cyrstalline) of ellipticine could be stabilized. These different states of ellipticine significantly affect the release kinetics of ellipticine from the peptide-ellipticine complex into the egg phosphatidylcholine vesicles, which are used to mimic cell membranes. The transfer rate of protonated ellipticine from the complex to the vesicles is much faster than that of crystalline ellipticine. This observation may also be related to the size of the resulting complexes as revealed from the scanning electron micrographs. In addition, the complexes with protonated ellipticine are found to have a better anticancer activity against two cancer cell lines, A549 and MCF-7. This work forms the basis for studies of the peptide-ellipticine suspensions in vitro and in vivo leading to future development of self-assembling peptide-based delivery of hydrophobic anticancer drugs. [source] Surface Activation of a Ferrimagnetic Glass,Ceramic for Antineoplastic Drugs GraftingADVANCED ENGINEERING MATERIALS, Issue 7 2010Enrica Vernè A ferrimagnetic glass,ceramic, belonging to the system SiO2,Na2O,CaO,P2O5,FeO,Fe2O3, has been studied as potential carrier for antineoplastic agents, in order to exploit the combination of hyperthermia and chemotherapy. Different material pre-treatments, such as ultrasonic washing, water, or simulated body fluid dipping, were evaluated to promote the surface activation of the glass,ceramic, i.e., the hydroxyl groups formation on it. X-ray photoelectron spectroscopy, scanning electron microscopy, energy dispersion spectrometry, and wettability measurements were performed to observe the samples surface modification. The best results in terms of free hydroxyl groups exposition were obtained by dipping the samples in distilled water for 7 days at 37,°C. Two different anticancer drugs were selected in order to test the reactivity of the activated surface: cisplatinum and doxorubicin. The uptake and release of doxorubicin and cisplatinum were evaluated on glass,ceramic powders, by using UV,Visible spectrometry and graphite furnace atomic absorption spectroscopy, respectively. After 1 day of uptake at 37,°C, the quantity of doxorubicin incorporated into the glass,ceramic is 77,±,7 wt%, while only 42,±,9.6 wt% of cisplatinum is grafted onto the material surface. For both antitumoral agents, the maximum drug release after soaking in aqueous solutions at 37,°C was obtained in few hours, with a randomly distributed kinetics trend. [source] Injectable and thermosensitive poly(organophosphazene) hydrogels for a 5-fluorouracil deliveryJOURNAL OF APPLIED POLYMER SCIENCE, Issue 6 2009Sun Mi Lee Abstract The drug solubility and its release profiles of an anticancer drug from an injectable thermosensitive poly(organophosphazene) hydrogel bearing hydrophobic L -isoleucine ethyl ester and hydrophilic ,-amino-,-methoxy-poly(ethylene glycol) with and without hydrolysis-sensitive glycyl lactate ethyl ester or functional glycyl glycine have been investigated. 5-Fluorouracil (5-FU) was used as a model anticancer drug. The aqueous solutions of 5-FU incorporated poly(organophosphazenes) were an injectable fluid state at room temperature and formed a transparent gel at body temperature. The poly(organophosphazene) solution could enhance the solubility of 5-FU and its solubility (34.26 mg/mL) was increased up to 10-fold compared to that in phosphate-buffered saline (3.39 mg/mL, pH 7.4, 4°C). The in vitro drug release profiles from poly(organophosphazene) hydrogels were established in phosphate-buffered saline at pH 7.4 at 37°C and the release of 5-FU was significantly affected by the diffusion-controlled stage. The results suggest that the injectable and thermosensitive poly(organophosphazene) hydrogel is a potential carrier for 5-FU to increase its solubility, control a relatively sustained and localized release at target sites and thus decrease systemic side effects. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 [source] An intelligent logistics support system for enhancing the airfreight forwarding businessEXPERT SYSTEMS, Issue 5 2004H.C.W. Lau Abstract: Recent research related to the aircraft container loading and scheduling problem for airfreight forwarding business has seen significant advances in terms of load plan optimization, taking into account the cost and volume of packed boxes. In today's competitive industrial environment, it is essential that freight forwarders are able to collaborate with carriers (airline companies) to achieve the best possible selection of logistics workflow. However, study of contemporary research publications indicates that there is a dearth of articles related to the design and implementation of an intelligent logistics system to support decision-making on carrier selection, aircraft container loading plans as well as carrier benchmarking. This paper presents an intelligent logistics support system (ILSS) which is able to provide expert advice related to the airfreight forwarding business, enhancing the logistics operations in relevant activities within the value chain of tasks. ILSS comprises a heuristics-based intelligent expert system which supports carrier searching and cargo trading planning as well as load plan generation. The proposed approach is meant to enhance various operations in the airfreight forwarding business, adopting computational intelligence technologies such as rule-based reasoning to provide domain advice and heuristics to support the generation of load plans. After potential outcomes are generated by the heuristics-based intelligent expert system, a neural network engine is applied to support prediction of unexpected events. To validate the viability of this approach, a production system using the ILSS has been developed and subsequently applied in an emulated airfreight forwarding environment. The application results indicate that the operation time from searching for potential carriers to the execution of the order is greatly reduced. In this paper, details related to the structure, design and implementation of the ILSS are also covered with the inclusion of the actual program codes for building the prototype. [source] Carrier testing in haemophilia A and B: adult carriers' and their partners' experiences and their views on the testing of young femalesHAEMOPHILIA, Issue 3 2008N. F. DUNN Summary., This is a descriptive study, which aims to report adult carriers' and their husbands/partners' experiences of carrier diagnosis and their views as to how these issues should be handled for the next generation. Following an initial pilot, 105 carriers and husbands/partners responded to a postal questionnaire. Most of the adult carriers had been tested because either they or their parents wanted to know their carrier status or they had a son diagnosed with haemophilia. The respondents agreed that the main reasons for testing young potential carriers should be either a family history of severe haemophilia or that the young person or her parents wanted to know her status. Forty per cent (35/87) believed the earliest age for carrier testing should be 0,9 years, 44% (38/87) 10,15 years and 16% (14/87) ,16 years. Respondents aged 18,39 years were more likely to be in favour of testing <2 years. If parents and teenagers disagreed, the majority of parents thought that a test should not be forced, consent refused or results withheld. Genetic counselling provides an important opportunity for parents, who want a very early genetic test, to explore their motivations and balance their desire to prepare and protect their daughter with her right to decide as a teenager. [source] Novel high-throughput SNP genotyping cosegregation analysis for genetic diagnosis of autosomal recessive retinitis pigmentosa and Leber congenital amaurosis,HUMAN MUTATION, Issue 5 2007Esther Pomares Abstract Retinitis pigmentosa (RP), the major cause of blindness in adults, is an extremely heterogeneous monogenic disorder. More than 32 causative genes have been identified, 18 of which are involved in autosomal recessive RP (arRP); however, more than 50% of the cases remain unassigned. There are no major causative genes identified for arRP nor any prevalent mutations, which make mutational screening of the already reported RP genes extremely time consuming and costly. Nonetheless, this step is unavoidable for genetic diagnosis of patients and potential carriers, and it is a prerequisite before approaching the identification of new RP genes and loci. We have designed an innovative high-throughput time- and cost-effective strategy for cosegregation analysis of 22 genes of arRP and Leber congenital amaurosis (LCA; an autosomal recessive retinal dystrophy that shares some of the RP genes and traits) by SNP genotyping. This novel indirect method has been validated in a panel of 54 consanguineous and nonconsanguineous arRP families. In a single and fast genotyping step: 1) we discarded all the 22 candidate genes in 13% of the pedigrees, highlighting the families of choice to search for novel arRP genes/loci; 2) we excluded an average of 18,19 genes per family, thus diminishing the number of genes to screen for pathogenic mutations; and 3) we identified CERKL as the causative RP gene in a family in which this candidate had been previously discarded by microsatellite cosegregation analysis. This type of approach can also be applied to other nonretinal diseases with high genetic heterogeneity, such as hereditary deafness or Parkinson disease. Hum Mutat 28(5), 511,516, 2007. © 2007 Wiley-Liss, Inc. [source] Investigation of wild caught whitefish, Coregonus lavaretus (L.), for infection with viral haemorrhagic septicaemia virus (VHSV) and experimental challenge of whitefish with VHSVJOURNAL OF FISH DISEASES, Issue 7 2004H F Skall Abstract One hundred and forty-eight wild whitefish, Coregonus lavaretus (L.), were caught by electrofishing and sampled for virological examination in December 1999 and 2000, during migration from the brackish water feeding grounds to the freshwater spawning grounds, where the whitefish may come into contact with farmed rainbow trout. All samples were examined on cell cultures. No viruses were isolated. Three viral haemorrhagic septicaemia virus (VHSV) isolates of different origin were tested in infection trials by immersion and intraperitoneal (IP) injection, using 1.5 g farmed whitefish: an isolate from wild caught marine fish, a farmed rainbow trout isolate with a suspected marine origin and a classical freshwater isolate. The isolates were highly pathogenic by IP injection where 99,100% of the whitefish died. Using an immersion challenge the rainbow trout isolates were moderately pathogenic with approximately 20% mortality, whereas the marine isolate was virtually non-pathogenic. At the end of the experiment it was possible to isolate VHSV from survivors infected with the marine and suspected marine isolates. Because of the low infection rate in wild whitefish in Denmark, the role of whitefish in the spread of VHSV in Denmark is probably not significant. The experimental studies, however, showed that whitefish are potential carriers of VHSV as they suffer only low mortality after infection but continue to carry virus. [source] Review: doxorubicin delivery systems based on chitosan for cancer therapyJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 2 2009Mei Lin Tan Abstract Objectives This review sheds insight into an increasingly popular polymer that has been widely explored as a potential drug delivery system. The abundant, biodegradable and biocompatible polysaccharide chitosan, with many other favourable properties, has been favoured as a drug delivery system for the purposes of encapsulating and delivery of doxorubicin with reduced side-effects. Key findings Doxorubicin is frequently used as a frontline chemotherapeutic agent against a variety of cancers. It has largely been able to demonstrate anti-tumour effects, though there are major shortfalls of doxorubicin, which include serious side-effects such as cardiomyopathy and myelosuppression, and also an ever-present danger of extravasation during drug administration. In view of this, drug delivery systems are currently being explored as alternative methods of drug delivery in a bid to more effectively direct doxorubicin to the specific lesion site and reduce its systemic side-effects. Liposomes and dendrimers have been tested as potential carriers for doxorubicin; however they are not the focus of this review. Summary Recent advancements in doxorubicin and chitosan technology have shown some preliminary though promising results for cancer therapy. [source] Synthesis and Biological Evaluation of Distamycin Analogues , New Potential Anticancer AgentsARCHIV DER PHARMAZIE, Issue 2 2009Danuta Drozdowska Abstract Eight of analogues of distamycin, potential minor-groove binders, were synthesized and tested for in-vitro cytotoxicity towards human breast cancer cells MCF-7 and MDA-MB-231. The method of synthesis is simple and convenient. All of the compounds 1,8 showed antiproliferative and cytotoxic effects against both cell lines in the range 3.47 to 12.53 ,M for MDA-MB-231 and 4.35 to 12.66 ,M for MCF-7. All compounds demonstrated activity against DNA topoisomerases I and II at a concentration of 50 ,M. The ethidium bromide assay showed that these compounds bind to plasmid pBR322, yet weaker than distamycin. Further investigations concerning the mechanism of cytotoxicity are now in progress, but the IC50 values suggest that synthetic distamycin analogues with a free amino group, 3,4 and 7,8, can serve as potential carriers of strong acting elements, e. g. alkylating groups. [source] | |||||||||||||