Kalhapure, Rahul S; Suleman, Nadia; Mocktar, Chunderika; Seedat, Nasreen; Govender, Thirumala
Formulation scientists are recognizing nanoengineered drug delivery systems as an effective strategy to overcome limitations associated with antibiotic drug therapy. Antibiotics encapsulated into nanodelivery systems will contribute to improved management of patients with various infectious diseases and to overcoming the serious global burden of antibiotic resistance. An extensive review of several antibiotic-loaded nanocarriers that have been formulated to target drugs to infectious sites, achieve controlled drug release profiles, and address formulation challenges, such as low-drug entrapment efficiencies, poor solubility and stability is presented in this paper. The physicochemical properties and the in vitro/in vivo performances of various antibiotic-loaded delivery systems, such as polymeric nanoparticles, micelles, dendrimers, liposomes, solid lipid nanoparticles, lipid-polymer hybrid nanoparticles, nanohybirds, nanofibers/scaffolds, nanosheets, nanoplexes, and nanotubes/horn/rods and nanoemulsions, are highlighted and evaluated. Future studies that will be essential to optimize formulation and commercialization of these antibiotic-loaded nanosystems are also identified. The review presented emphasizes the significant formulation progress achieved and potential that novel nanoengineered antibiotic drug delivery systems have for enhancing the treatment of patients with a range of infections.
Kluin, Otto S.; van der Mei, Henny C.; Busscher, Henk J.; Neut, Danielle
Biodegradable delivery systems that do not produce acidic compounds during degradation are preferred for local antibiotic delivery in bone infections in order to avoid adverse bone reactions. Poly(trimethylene carbonate) (PTMC) has good biocompatibility, and is such a polymer. The objective of this
Patel, Apurv; Dodiya, Hitesh; Shelate, Pragna; Shastri, Divyesh; Dave, Divyang
The objective of this work was design, characterization, and optimization of controlled drug delivery system containing antibiotic drug/s. Osmotic drug delivery system was chosen as controlled drug delivery system. The porous osmotic pump tablets were designed using Plackett-Burman and Box-Behnken factorial design to find out the best formulation. For screening of three categories of polymers, six independent variables were chosen for Plackett-Burman design. Osmotic agent sodium chloride and microcrystalline cellulose, pore forming agent sodium lauryl sulphate and sucrose, and coating agent ethyl cellulose and cellulose acetate were chosen as independent variables. Optimization of osmotic tablets was done by Box-Behnken design by selecting three independent variables. Osmotic agent sodium chloride, pore forming agent sodium lauryl sulphate, and coating agent cellulose acetate were chosen as independent variables. The result of Plackett-Burman and Box-Behnken design and ANOVA studies revealed that osmotic agent and pore former had significant effect on the drug release up to 12 hr. The observed independent variables were found to be very close to predicted values of most satisfactory formulation which demonstrates the feasibility of the optimization procedure in successful development of porous osmotic pump tablets containing antibiotic drug/s by using sodium chloride, sodium lauryl sulphate, and cellulose acetate as key excipients. PMID:27610247
Abed, Nadia; Saïd-Hassane, Fatouma; Zouhiri, Fatima; Mougin, Julie; Nicolas, Valérie; Desmaële, Didier; Gref, Ruxandra; Couvreur, Patrick
The "Golden era" of antibiotics is definitely an old story and this is especially true for intracellular bacterial infections. The poor intracellular bioavailability of antibiotics reduces the efficency of many treatments and thereby promotes resistances. Therefore, the development of nanodevices coupled with antibiotics that are capable of targeting and releasing the drug into the infected-cells appears to be a promising solution to circumvent these complications. Here, we took advantage of two natural terpenes (farnesyl and geranyl) to design nanodevices for an efficient intracellular delivery of penicillin G. The covalent linkage between the terpene moieties and the antibiotic leads to formation of prodrugs that self-assemble to form nanoparticles with a high drug payload between 55-63%. Futhermore, the addition of an environmentally-sensitive bond between the antibiotic and the terpene led to an efficient antibacterial activity against the intracellular pathogen Staphylococcus aureus with reduced intracellular replication of about 99.9% compared to untreated infected cells. Using HPLC analysis, we demonstrated and quantified the intracellular release of PenG when this sensitive-bond (SB) was present on the prodrug, showing the success of this technology to deliver antibiotics directly into cells.
Nadia Abed; Fatouma Saïd-Hassane; Fatima Zouhiri; Julie Mougin; Valérie Nicolas; Didier Desmaële; Ruxandra Gref; Patrick Couvreur
The “Golden era” of antibiotics is definitely an old story and this is especially true for intracellular bacterial infections. The poor intracellular bioavailability of antibiotics reduces the efficency of many treatments and thereby promotes resistances. Therefore, the development of nanodevices coupled with antibiotics that are capable of targeting and releasing the drug into the infected-cells appears to be a promising solution to circumvent these complications. Here, we took advantage of ...
Halpern, Jeffrey M.; Gormley, Catherine A.; Keech, Melissa; von Recum, Horst A.
Various local drug delivery devices and coatings are being developed as slow, sustained release mechanism for drugs, yet the polymers are typically not evaluated after commercial sterilization techniques. We examine the effect that commercial sterilization techniques have on the physical, mechanical, and drug delivery properties of polyurethane polymers. Specifically we tested cyclodextrin-hexamethyl diisocyanate crosslinked polymers before and after autoclave, ethylene oxide, and gamma radia...
Yang, Rong; Sabharwal, Vishakha; Okonkwo, Obiajulu S; Shlykova, Nadya; Tong, Rong; Lin, Lily Yun; Wang, Weiping; Guo, Shutao; Rosowski, John J; Pelton, Stephen I; Kohane, Daniel S
Otitis media is the most common reason U.S. children receive antibiotics. The requisite 7- to 10-day course of oral antibiotics can be challenging to deliver in children, entails potential systemic toxicity, and encourages selection of antimicrobial-resistant bacteria. We developed a drug delivery system that, when applied once to the tympanic membrane through the external auditory canal, delivers an entire course of antimicrobial therapy to the middle ear. A pentablock copolymer poloxamer 407-polybutylphosphoester (P407-PBP) was designed to flow easily during application and then to form a mechanically strong hydrogel on the tympanic membrane. U.S. Food and Drug Administration-approved chemical permeation enhancers within the hydrogel assisted flux of the antibiotic ciprofloxacin across the membrane. This drug delivery system completely eradicated otitis media from nontypable Haemophilus influenzae (NTHi) in 10 of 10 chinchillas, whereas only 62.5% of animals receiving 1% ciprofloxacin alone had cleared the infection by day 7. The hydrogel system was biocompatible in the ear, and ciprofloxacin was undetectable systemically (in blood), confirming local drug delivery and activity. This fast-gelling hydrogel could improve compliance, minimize side effects, and prevent systemic distribution of antibiotics in one of the most common pediatric illnesses, possibly minimizing the development of antibiotic resistance. PMID:27629487
Mumuni Audu Momoh; Charles Okechukwu Esimone
Objective: To formulate gentamicin liposphere by solvent-melting method using lipids and polyethylene glycol 4 000 (PEG-4 000) for oral administration. Methods: Gentamicin lipospheres were prepared by melt-emulsification using 30% w/w Phospholipon® 90H in Beeswax as the lipid matrix containing PEG-4 000. These lipospheres were characterized by evaluating on encapsulation efficiency, loading capacity, change in pH and the release profile. Antimicrobial activities were evaluated against Escherichia coli, Pseudomonas aeruginosa, Salmonella paratyphii and Staphylococcus aureus using the agar diffusion method. Results:Photomicrographs revealed spherical particles within a micrometer range with minimal growth after 1 month. The release of gentamicin in vitro varied widely with the PEG-4 000 contents. Moreover, significant (P>0.05) amount of gentamicin was released in vivo from the formulation. The encapsulation and loading capacity were all high, indicating the ability of the lipids to take up the drug. The antimicrobial activities were very high especially against Pseudomonas compare to other test organisms. This strongly suggested that the formulation retain its bioactive characteristics. Conclusions: This study strongly suggest that the issue of gentamicin stability and poor absorption in oral formulation could be adequately addressed by tactical engineering of lipid drug delivery systems such as lipospheres.
This article provides a critical view of the current state of the development of nanoparticulate and other solid-state carriers for the local delivery of antibiotics in the treatment of osteomyelitis. Mentioned are the downsides of traditional means for treating bone infection, which involve systemic administration of antibiotics and surgical debridement, along with the rather imperfect local delivery options currently available in the clinic. Envisaged are more sophisticated carriers for the local and sustained delivery of antimicrobials, including bioresorbable polymeric, collagenous, liquid crystalline, and bioglass- and nanotube-based carriers, as well as those composed of calcium phosphate, the mineral component of bone and teeth. A special emphasis is placed on composite multifunctional antibiotic carriers of a nanoparticulate nature and on their ability to induce osteogenesis of hard tissues demineralized due to disease. An ideal carrier of this type would prevent the long-term, repetitive, and systemic administration of antibiotics and either minimize or completely eliminate the need for surgical debridement of necrotic tissue. Potential problems faced by even hypothetically "perfect" antibiotic delivery vehicles are mentioned too, including (i) intracellular bacterial colonies involved in recurrent, chronic osteomyelitis; (ii) the need for mechanical and release properties to be adjusted to the area of surgical placement; (iii) different environments in which in vitro and in vivo testings are carried out; (iv) unpredictable synergies between drug delivery system components; and (v) experimental sensitivity issues entailing the increasing subtlety of the design of nanoplatforms for the controlled delivery of therapeutics. PMID:25746204
Full Text Available Systemic antibiotics in conjunction with scaling and root planing (SRP, can offer an additional benefit over SRP alone in the treatment of periodontitis, in terms of clinical attachment loss (CAL and pocket depth change, and reduced risk of additional CAL loss. However, antibiotics are not innocuous drugs. Their use should be justified on the basis of a clearly established need and should not be substituted for adequate local treatment. The aim of this review is to discuss the rationale, proper selection, dosage and duration for antibiotic therapy so as to optimize the usefulness of drug therapy.
Anoop Kapoor; Ranjan Malhotra; Vishakha Grover; Deepak Grover
Systemic antibiotics in conjunction with scaling and root planing (SRP), can offer an additional benefit over SRP alone in the treatment of periodontitis, in terms of clinical attachment loss (CAL) and pocket depth change, and reduced risk of additional CAL loss. However, antibiotics are not innocuous drugs. Their use should be justified on the basis of a clearly established need and should not be substituted for adequate local treatment. The aim of this review is to discuss the rationale, pr...
Full Text Available Objective: To evaluate the activity and sustained release of antibiotics from fibrin sealant against common strains of ocular bacteria. Methods: Vancomycin, ceftazidime, moxifloxacin and lomefloxacin were incorporated into fibrin sealant in the shape of discs. Each antibiotic disc and control fibrin disc without drug was tested in vitro against standard bacterial strains of Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pneumoniae and Pseudomonas aeroginosa. After 24 hours of incubation at 37 °C, the discs were transferred to new plates of bacteria and triplicated for each antibiotic. Results: All antibiotic discs demonstrated detectable activity after 24 hours. Vancomycin had the longest duration of activity (4 days on the S. pneumonia grown plate. The moxifloxacin discs showed a prolonged inhibition of S. aureus and S. pneumonia for 3 days and inhibited the other strains for 2 days. Conclusion: Fibrin sealants provided prolonged drug delivery, which indicates that antibiotic-loaded fibrin clots could be useful for early ocular postoperative care and treatment. J Clin Exp Invest 2014; 5 (2: 194-199
Sarkar Biresh K; Jain Devananda; Banerjee Angshu
Incorporating an existing medicine into a new drug delivery system can significantly improve its performance in terms of efficacy, safety, and improved patient compliance. The need for delivering drugs to patients efficiently and with fewer side effects has prompted pharmaceutical companies to engage in the development of new drug delivery systems. Today, drug delivery companies are engaged in the development of multiple platform technologies for controlled release, delivery of large molecule...
Sarkar Biresh K
Full Text Available Incorporating an existing medicine into a new drug delivery system can significantly improve its performance in terms of efficacy, safety, and improved patient compliance. The need for delivering drugs to patients efficiently and with fewer side effects has prompted pharmaceutical companies to engage in the development of new drug delivery systems. Today, drug delivery companies are engaged in the development of multiple platform technologies for controlled release, delivery of large molecules, liposome, taste-masking, oral fast- dispersing dosage forms, technology for in- soluble drugs, and delivery of drugs through intranasal, pulmonary, transdermal, vaginal, colon, and transmucosal routes.
Stevens, F; Zee, J. van der
A health care delivery system is the organized response of a society to the health problems of its inhabitants. Societies choose from alternative health care delivery models and, in doing so, they organize and set goals and priorities in such a way that the actions of different actors are effective, meaningful, and socially accepted. From a sociological point of view, the analysis of health care delivery systems implies recognition of their distinct history over time, their specific values an...
As business environments become increasingly competitive, companies seek more comprehensive solutions to the delivery of their projects. "Project Delivery System: Fourth Edition" describes the process-driven project delivery systems which incorporates the best practices from Total Quality and is aligned with the Project Management Institute and ISO Quality Standards is the means by which projects are consistently and efficiently planned, executed and completed to the satisfaction of clients and customers.
Inzana, J A; Trombetta, R P; Schwarz, E M; Kates, S L; Awad, H A
Surgical implant-associated bone infections (osteomyelitis) have severe clinical and socioeconomic consequences. Treatment of chronic bone infections often involves antibiotics given systemically and locally to the affected site in poly (methyl methacrylate) (PMMA) bone cement. Given the high antibiotic concentrations required to affect bacteria in biofilm, local delivery is important to achieve high doses at the infection site. PMMA is not suitable to locally-deliver some biofilm-specific antibiotics, including rifampin, due to interference with PMMA polymerisation. To examine the efficacy of localised, combinational antibiotic delivery compared to PMMA standards, we fabricated rifampin- and vancomycin-laden calcium phosphate scaffolds (CPS) by three-dimensional (3D) printing to treat an implant-associated Staphylococcus aureus bone infection in a murine model. All vancomycin- and rifampin-laden CPS treatments significantly reduced the bacterial burden compared with vancomycin-laden PMMA. The bones were bacteria culture negative in 50 % of the mice that received sustained release vancomycin- and rifampin-laden CPS. In contrast, 100 % of the bones treated with vancomycin monotherapy using PMMA or CPS were culture positive. Yet, the monotherapy CPS significantly reduced the bacterial metabolic load following revision compared to PMMA. Biofilm persisted on the fixation hardware, but the infection-induced bone destruction was significantly reduced by local rifampin delivery. These data demonstrate that, despite the challenging implant-retaining infection model, co-delivery of rifampin and vancomycin from 3D printed CPS, which is not possible with PMMA, significantly improved the outcomes of implant-associated osteomyelitis. However, biofilm persistence on the fixation hardware reaffirms the importance of implant exchange or other biofilm eradication strategies to complement local antibiotics.
Benoit, M.-A.; Mousset, B.; Delloye, C.; Bouillet, R.; Gillard, J.
m) of PLA45GA10. This delivery system was implanted into the femoral condyle of rabbits. It was shown that the in vivo release was also closely regulated by the coating depth. In all bone tissues (bone marrow and cortical bone) surrounding the pellets, the drug concentration exceeded the Minimum Inhibitory Concentration for the common causative organisms of bone infections (Staphylococcus aureus) for at least four weeks without inducing serum toxic levels. Due to its cheapness, facility of us...
Stevens, F.; Zee, J. van der
A health care delivery system is the organized response of a society to the health problems of its inhabitants. Societies choose from alternative health care delivery models and, in doing so, they organize and set goals and priorities in such a way that the actions of different actors are effective,
Ravi Kant Upadhyay
Present review highlights various drug delivery systems used for delivery of pharmaceutical agents mainly antibiotics, antineoplastic agents, neuropeptides, and other therapeutic substances through the endothelial capillaries (BBB) for CNS therapeutics. In addition, the use of ultrasound in delivery of therapeutic agents/biomolecules such as proline rich peptides, prodrugs, radiopharmaceuticals, proteins, immunoglobulins, and chimeric peptides to the target sites in deep tissue locations insi...
Vishvakarama Prabhakar; Agarwal Shivendra; Sharma Ritika; Saurabh Sharma
Various new technologies have been developed for the transdermal delivery of some important drugs. Today about 74% of drugs are taken orally and are found not to be as effective as desired. To improve such characters transdermal drug delivery system was emerged. Drug delivery through the skin to achieve a systemic effect of a drug is commonly known as transdermal drug delivery and differs from traditional topical drug delivery. Transdermal drug delivery systems (TDDS) are dosage forms involve...
陈卫; 王永禄; 李学明; 孙小虎
近年来,耐药菌感染率居高不下.细菌主要通过减少药物摄取和增加外排、改变靶位、钝化或酶解药物等机制,对各种抗生素产生耐药.本文综述国内外通过载体系统克服耐药的新技术,如脂质体、纳米粒、无机金属载体等.脂质体和纳米粒由于生物相容性和降解性较好,且能靶向网状内皮系统,应用较多.本文主要是介绍近十年来,国外载体系统在抗生素抗耐药菌方面的研究情况,这些载体能克服部分耐药机制,如改变细菌细胞膜,而增加药物在感染部位的浓度,并且减少毒副作用.%In recent years, drug-resistant bacteria and the incidence of intracellular infection were increasing. Antibiotic resistance is the phenomenon that bacteria exhibit significantly reduced susceptibility to antimicrobials by mechanisms such as altered drug uptake and increase efflux, altered drug target and drug inactivation. The current technologies for increasing the bioavailability by novel delivery systems to overcome resistance of antibiotics were reviewed, such as liposomes, nanoparticles and inorganic metal carrier. Liposomes and nanoparticles have good biocompatibility and degradation ability and can target the reticuloendothelial system, so they are widely used. The purpose of this review is to provide background information in antibiotic delivery systems gathered from papers published over the last ten years. It seems clear that such drug carriers can increase drug concentration at infected sites and reduce drug toxicity by overcome some resistance mechanisms, such as changing the bacterial cell membranes.
Full Text Available Mucoadhesion is commonly defined as the adhesion between two materials, at least one of which is a mucosal surface. Over the past few decades, mucosal drug delivery has received a great deal of attention. Mucoadhesive dosage forms may be designed to enable prolonged retention at the site of application, providing a controlled rate of drug release for improved therapeutic outcome. Application of dosage forms to mucosal surfaces may be of benefit to drug molecules not amenable to the oral route, such as those that undergo acid degradation or extensive first-pass metabolism. The mucoadhesive ability of a dosage form is dependent upon a variety of factors, including the nature of the mucosal tissue and the physicochemical properties of the polymeric formulation. This review article aims to provide an overview of the various aspects of mucoadhesion, mucoadhesive materials, factors affecting mucoadhesion, evaluating methods, and finally various mucoadhesive drug delivery systems (buccal, nasal, ocular, gastro, vaginal, and rectal.
Cobo, Angelica; Sheybani, Roya; Meng, Ellis
Drug delivery systems play a crucial role in the treatment and management of medical conditions. Microelectromechanical systems (MEMS) technologies have allowed the development of advanced miniaturized devices for medical and biological applications. This Review presents the use of MEMS technologies to produce drug delivery devices detailing the delivery mechanisms, device formats employed, and various biomedical applications. The integration of dosing control systems, examples of commercially available microtechnology-enabled drug delivery devices, remaining challenges, and future outlook are also discussed.
Prokop, Ales; Davidson, Jeffrey M
This article provides an overview of principles and barriers relevant to intracellular drug and gene transport, accumulation and retention (collectively called as drug delivery) by means of nanovehicles (NV). The aim is to deliver a cargo to a particular intracellular site, if possible, to exert a local action. Some of the principles discussed in this article apply to noncolloidal drugs that are not permeable to the plasma membrane or to the blood-brain barrier. NV are defined as a wide range of nanosized particles leading to colloidal objects which are capable of entering cells and tissues and delivering a cargo intracelullarly. Different localization and targeting means are discussed. Limited discussion on pharmacokinetics and pharmacodynamics is also presented. NVs are contrasted to micro-delivery and current nanotechnologies which are already in commercial use. Newer developments in NV technologies are outlined and future applications are stressed. We also briefly review the existing modeling tools and approaches to quantitatively describe the behavior of targeted NV within the vascular and tumor compartments, an area of particular importance. While we list "elementary" phenomena related to different level of complexity of delivery to cancer, we also stress importance of multi-scale modeling and bottom-up systems biology approach. PMID:18200527
Westerman, E.M.; Heijerman, H.G.M.; Frijlink, H.W.
Inhalation of antipseudomonal antibiotics is a cornerstone in treating cystic fibrosis patients. It has shown to be effective in slowing down the process of pulmonary deterioration and decreasing the incidence of infectious exacerbations. The focus is now on innovating drug delivery devices, sometim
Antibiotics are powerful medicines that fight bacterial infections. Used properly, antibiotics can save lives. They either kill bacteria or ... natural defenses can usually take it from there. Antibiotics do not fight infections caused by viruses, such ...
Kasner, James H.; Brower, Bernard V.
In this paper we present formats and delivery methods of Large Volume Streaming Data (LVSD) systems. LVSD systems collect TBs of data per mission with aggregate camera sizes in the 100 Mpixel to several Gpixel range at temporal rates of 2 - 60 Hz. We present options and recommendations for the different stages of LVSD data collection and delivery, to include the raw (multi-camera) data, delivery of processed (stabilized mosaic) data, and delivery of user-defined region of interest windows. Many LVSD systems use JPEG 2000 for the compression of raw and processed data. We explore the use of the JPEG 2000 Interactive Protocol (JPIP) for interactive client/server delivery to thick-clients (desktops and laptops) and MPEG-2 and H.264 to handheld thin-clients (tablets, cell phones). We also explore the use of 3D JPEG 2000 compression, defined in ISO 15444-2, for storage and delivery as well. The delivery of raw, processed, and region of interest data requires different metadata delivery techniques and metadata content. Beyond the format and delivery of data and metadata we discuss the requirements for a client/server protocol that provides data discovery and retrieval. Finally, we look into the future as LVSD systems perform automated processing to produce "information" from the original data. This information may include tracks of moving targets, changes of the background, snap shots of targets, fusion of multiple sensors, and information about "events" that have happened.
Full Text Available The human skin is a readily accessible surface for drug delivery. Skin of an average adult body covers a surface of approximately 2 m2 and receives about one-third of the blood circulating through the body. Over the past decades, developing controlled drug delivery has become increasingly important in the pharmaceutical industry. The human skin surface is known to contain, on an average, 10- 70 hair follicles and 200-250 sweat ducts on every square centimeters of the skin area. It is one of the most readily accessible organs of the human body. There is considerable interest in the skin as a site of drug application both for local and systemic effect. However, the skin, in particular the stratum corneum, poses a formidable barrier to drug penetration thereby limiting topical and transdermal bioavailability. Skin penetration enhancement techniques have been developed to improve bioavailability and increase the range of drugs for which topical and transdermal delivery is a viable option. During the past decade, the number of drugs formulated in the patches has hardly increased, and there has been little change in the composition of the patch systems. Modifications have been mostly limited to refinements of the materials used. The present review article explores the overall study on transdermal drug delivery system (TDDS which leads to novel drug delivery system (NDDS.
Stockwell, Jocelyn; Abdi, Nabiha; Lu, Xiaofan; Maheshwari, Oshin; Taghibiglou, Changiz
For decades, biomedical and pharmaceutical researchers have worked to devise new and more effective therapeutics to treat diseases affecting the central nervous system. The blood-brain barrier effectively protects the brain, but poses a profound challenge to drug delivery across this barrier. Many traditional drugs cannot cross the blood-brain barrier in appreciable concentrations, with less than 1% of most drugs reaching the central nervous system, leading to a lack of available treatments for many central nervous system diseases, such as stroke, neurodegenerative disorders, and brain tumors. Due to the ineffective nature of most treatments for central nervous system disorders, the development of novel drug delivery systems is an area of great interest and active research. Multiple novel strategies show promise for effective central nervous system drug delivery, giving potential for more effective and safer therapies in the future. This review outlines several novel drug delivery techniques, including intranasal drug delivery, nanoparticles, drug modifications, convection-enhanced infusion, and ultrasound-mediated drug delivery. It also assesses possible clinical applications, limitations, and examples of current clinical and preclinical research for each of these drug delivery approaches. Improved central nervous system drug delivery is extremely important and will allow for improved treatment of central nervous system diseases, causing improved therapies for those who are affected by central nervous system diseases.
Li, Ping; Tan, Angel; Prestidge, Clive A;
This study aims at evaluating the combination of self-nanoemulsifying drug delivery systems (SNEDDS) and enteric-coated capsules as a potential delivery strategy for oral delivery of insulin. The SNEDDS preconcentrates, loaded with insulin-phospholipid complex at different levels (0, 2.5 and 10% w...
Full Text Available This review highlights the several advantages of buccal drug delivery system (BDDS over the conventional and systemic formulation majorly. It helps to enhance bioavailability through bypassing the first pass metabolism. On this drug delivery system the formulation keeps in contact with the mucosal surface resulting in better absorption and prolonged resident time. Though all drugs are not suitable for this drug delivery system yet is useful for most of the drugs. Bioadhesive polymers roles a major part in this drug delivery system because the extent of Mucoadhesion is a very important phenomena for the buccal drug delivery system. This review covers merits and demerits of buccal drug delivery system, anatomy of oral mucosa, mechanism of drug permeation, polymers and permeation enhancer used in buccal drug delivery system. This review also covers available marketed product as buccal drug delivery system and future aspects of buccal drug delivery system.
Robey, Robert W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
This presentation deals with the hierarchy of software build and delivery systems. One of the goals is to maximize the success rate of new users and developers when first trying your software. First impressions are important. Early successes are important. This also reduces critical documentation costs. This is a presentation focused on computer science and goes into detail about code documentation.
A method for the production of highly stable gold nanoparticles (Au NP) was optimized using sodium borohydride as reducing agent and bovine serum albumin as capping agent. The synthesized nanoparticles were characterized using UV–visible spectroscopy, transmission electron microscopy, X‐ray diffraction (XRD) and dynamic light scattering techniques. The formation of gold nanoparticles was confirmed from the appearance of pink colour and an absorption maximum at 532 nm. These protein capped nanoparticles exhibited excellent stability towards pH modification and electrolyte addition. The produced nanoparticles were found to be spherical in shape, nearly monodispersed and with an average particle size of 7.8 ± 1.7 nm. Crystalline nature of the nanoparticles in face centered cubic structure is confirmed from the selected‐area electron diffraction and XRD patterns. The nanoparticles were functionalized with various amino-glycosidic antibiotics for utilizing them as drug delivery vehicles. Using Fourier transform infrared spectroscopy, the possible functional groups of antibiotics bound to the nanoparticle surface have been examined. These drug loaded nanoparticle solutions were tested for their antibacterial activity against Gram-negative and Gram-positive bacterial strains, by well diffusion assay. The antibiotic conjugated Au NP exhibited enhanced antibacterial activity, compared to pure antibiotic at the same concentration. Being protein capped and highly stable, these gold nanoparticles can act as effective carriers for drugs and might have considerable applications in the field of infection prevention and therapeutics. - Highlights: ► Method for NaBH4 reduced and BSA capped gold nanoparticle was standardized. ► Nanoparticles were spherical and nearly monodispersed with a size of 7.8 nm. ► Nanoparticles are extremely stable towards pH modification and electrolyte addition. ► Antibiotic conjugated nanoparticles exhibited enhanced antibacterial activity
Transdermal drug delivery system (TDDS) are topically administered medicaments in the form of patches that deliver drugs for systemic effects at a predetermined and controlled rate. It works very simply in which drug is applied inside the patch and it is worn on skin for long period of time. By this constant concentration of drug remain in blood for long time. Polymer matrix, drug, permeation enhancers are the main components of TDDS; polymers includes Zein, Shellac (as a natural) to syntheti...
Zhou, Qi Tony; Leung, Sharon Shui Yee; Tang, Patricia; Parumasivam, Thaigarajan; Loh, Zhi Hui; Chan, Hak-Kim
Respiratory infections represent a major global health problem. They are often treated by parenteral administrations of antimicrobials. Unfortunately, systemic therapies of high-dose antimicrobials can lead to severe adverse effects and this calls for a need to develop inhaled formulations that enable targeted drug delivery to the airways with minimal systemic drug exposure. Recent technological advances facilitate the development of inhaled anti-microbial therapies. The newer mesh nebulisers have achieved minimal drug residue, higher aerosolisation efficiencies and rapid administration compared to traditional jet nebulisers. Novel particle engineering and intelligent device design also make dry powder inhalers appealing for the delivery of high-dose antibiotics. In view of the fact that no new antibiotic entities against multi-drug resistant bacteria have come close to commercialisation, advanced formulation strategies are in high demand for combating respiratory 'super bugs'.
Full Text Available There is a growing concern worldwide about the prevalence of antibiotics and antibiotic resistance genes (ARGs on the farm. In this study, we investigated the distribution of seven antibiotics and ten ARGs in fresh and dried pig feces, in biogas slurry, and in grape-planting soil from an ecological farm. Antibiotics including sulfamethazine, norfloxacin, ofloxacin, tetracycline, oxytetracycline, and chlortetracycline were detected in these samples (except for sulfamethoxazole in dried feces. In general, antibiotics levels in samples were in the sequence: biogas slurry > fresh feces > soil or dried feces. Results of ecological risk assessments revealed that among the seven antibiotics chlortetracycline showed the highest ecological risk. Among the ten ARGs, sulI and tetO were the most prevalent on this ecological farm. There were positive correlations between certain ARGs and the corresponding antibiotics on this ecological farm. Therefore, continuous monitoring of antibiotics and their corresponding ARGs should be conducted in the agroecosystem near the concentrated animal farming operation systems.
KALPESH CHHOTALAL ASHARA; Jalpa S. Paun; M. M. Soniwala; J.R.CHAVDA; S. V. NATHAWANI; NITIN M. MORI; Mendapara, Vishal P.
A novel drug delivery system is that delivers drug at predetermined rate decided as per the requirement, pharmacological aspects, drug profile, physiological conditions of body etc. In current conditions not a single novel drug delivery system behaves ideally those high goals with fewer side effects. A Vesicular drug delivery system (VDDS) is the system in which encapsulation of active moieties in vesicular structure, which bridges gap between ideal and available of novel drug delivery system...
Vaginal delivery is an important route of drug administration for both local and systemic diseases. The vaginal route has some advantages due to its large surface area, rich blood supply, avoidance of the first-pass effect, relatively high permeability to many drugs and self-insertion. The traditional commercial preparations, such as creams, foams, gels, irrigations and tablets, are known to reside in the vaginal cavity for a relatively short period of time owing to the self-cleaning action of the vaginal tract, and often require multiple daily doses to ensure the desired therapeutic effect. The vaginal route appears to be highly appropriate for bioadhesive drug delivery systems in order to retain drugs for treating largely local conditions, or for use in contraception. In particular, protection against sexually-transmitted diseases is critical. To prolong the residence time in the vaginal cavity, bioadhesive therapeutic systems have been developed in the form of semi-solid and solid dosage forms. The most commonly used mucoadhesive polymers that are capable of forming hydrogels are synthetic polyacrylates, polycarbophil, chitosan, cellulose derivatives (hydroxyethycellulose, hydroxy-propylcellulose and hydroxypropylmethylcellulose), hyaluronic acid derivatives, pectin, tragacanth, carrageenan and sodium alginate. The present article is a comprehensive review of the patents related to mucoadhesive vaginal drug delivery systems. PMID:19925443
Jorgensen, L; Moeller, E H; van de Weert, M;
From a formulation perspective proteins are complex and therefore challenging molecules to develop drug delivery systems for. The success of a formulation depends on the ability of the protein to maintain the native structure and activity during preparation and delivery as well as during shipping...... and long-term storage of the formulation. Therefore, the development and evaluation of successful and promising drug delivery systems is essential. In the present review, some of the particulate drug delivery systems for parenteral delivery of protein are presented and discussed. The challenge...... for incorporation of protein in particulate delivery systems is exemplified by water-in-oil emulsions....
U.S. Department of Health & Human Services — Explore the Electronic Nicotine Delivery Systems Key Facts Infographic which outlines key facts related to electronic nicotine delivery systems (ENDS), including...
Berger, D; Nastase, S; Mitran, R A; Petrescu, M; Vasile, E; Matei, C; Negreanu-Pirjol, T
Oxytetracycline delivery systems containing various MCM-type silica and aluminosilicate with different antibiotic content were developed in order to establish the influence of the support structural and textural properties and aluminum content on the drug release profile. The antibiotic molecules were loaded into the support mesochannels by incipient wetness impregnation method using a drug concentrated aqueous solution. The carriers and drug-loaded materials were investigated by small- and wide-angle XRD, FTIR spectroscopy, TEM and N2 adsorption-desorption isotherms. Faster release kinetics of oxytetracycline from uncalcined silica and aluminosilicate supports was observed, whereas higher drug content led to lower delivery rate. The presence of aluminum into the silica network also slowed down the release rate. The antimicrobial assays performed on Staphylococcus aureus clinical isolates showed that the oxytetracycline-loaded materials containing MCM-41-type mesoporous silica or aluminosilicate carriers inhibited the bacterial development. PMID:26861688
Full Text Available Helicobacter pylori (H. pylori, the major culprit for peptic ulcer, has a unique way of survival in harsh acidic environment of the stomach by colonizing deep in the gastric mucosal layer. Failure of conventional therapies against H. pylori for complete eradication has major limitations like low residence time of delivery system in stomach, poor penetration of drug in gastric mucosa, acidic degradation of antibiotics, and development of antibiotics resistance. The poor penetration of antibiotics through thick viscoelastic mucosal gel results in incomplete eradication of H. pylori. Various investigators have formulated novel gastro-retentive drug delivery systems such as floating systems, mucoadhesive systems, pH-sensitive gel systems, and muco-penetrating delivery systems for increasing the concentration of antibiotic in close proximity to the site of H. pylori infection. This review summarizes the novel drug delivery approaches investigated during the last few years and suggests that a high eradication rate can be achieved by therapy comprising of muco-penetrating delivery systems of antibiotics against H. pylori.
Full Text Available Conventional oral drug delivery systems supply an instantaneous release of drug, which cannot control the release of the drug and effective concentration at the target site. This kind of dosing pattern may result in constantly changing, unpredictable plasma concentrations. Drugs can be delivered in a controlled pattern over a long period of time by the process of osmosis. Osmotic devices are the most promising strategy based systems for controlled drug delivery. They are the most reliable controlled drug delivery systems and could be employed as oral drug delivery systems. Various patents available for osmotic drug delivery system like Rose-Nelson pump, Higuchi leeper pump, Higuchi Theeuwes pump, Elementary Osmotic pump etc. ODDS are useful for poorly soluble drug, for pulsatile drug release, zero order release. Various techniques available for preparation of ODDS include push pull osmotic Pump, osmotic Brusting osmotic pump, liquid oral osmotic system, sandwiched osmotic tablets , delayed delivery osmotic device, monolithic osmotic System and controlled porosity osmotic Pump. Osmotically controlled oral drug delivery systems utilize osmotic pressure for controlled delivery of active agents. These systems can be utilized for systemic as well as targeted delivery of drugs. The release of drugs from osmotic systems is governed by various formulation factors such as solubility and osmotic pressure of the core components, size of the delivery orifice, and nature of the rate-controlling membrane. In this Paper mainly focused on the Osmotic System with example, the basic component of osmotic system and evaluation parameter of the osmotic drug delivery system.
KALPESH CHHOTALAL ASHARA
Full Text Available A novel drug delivery system is that delivers drug at predetermined rate decided as per the requirement, pharmacological aspects, drug profile, physiological conditions of body etc. In current conditions not a single novel drug delivery system behaves ideally those high goals with fewer side effects. A Vesicular drug delivery system (VDDS is the system in which encapsulation of active moieties in vesicular structure, which bridges gap between ideal and available of novel drug delivery system.Varrious types of vesicular drug delivery system like liposome, niosome, archeosome, transferosome etc. were developed. Advances have since been made in vesicular drug delivery system. Focus of this review is to bring about a brief of vesicular drug delivery system as novel approach.
Raphael M. Ottenbrite; ZHAO Ruifeng; Sam Milstein
An oral drug delivery system using proteinoid microspheres is discussed with respect to its unique dependence on pH. It has been found that certain drugs such as insulin and heparin can be encapsulated in proteinoid spheres at stomach pH's (1-3). These spheres also dissemble at intestinal pH's (6-7) releasing the drug for absorption. Using this technique low molecular weight heparin and human growth hormone have been orally delivered successfully to several animal species. Future work has been proposed to study the interaction and binding of the specific drugs with synthesized oligopeptides.
Full Text Available Transdermal drug delivery system (TDDS are topically administered medicaments in the form of patches that deliver drugs for systemic effects at a predetermined and controlled rate. It works very simply in which drug is applied inside the patch and it is worn on skin for long period of time. By this constant concentration of drug remain in blood for long time. Polymer matrix, drug, permeation enhancers are the main components of TDDS; polymers includes Zein, Shellac (as a natural to synthetic ones (Polybutadiene, Polysiloxane, Polyvinyl chloride, Polyvinyl alcohol etc.. TDDS are of many types varying from single layer drug in adhesive to multi layer drug in adhesive and others are reservoir and the matrix systems. The market value of TDDS products are increasing with rapid rate, more than 35 products have now been approved for sale in US, and approximately 16 active ingredients are approved globally for use as a TDDS. Transdermal drug delivery is a recent technology which promises a great future it has a potential to limit the use of needles for administering wide variety of drugs but cost factor is a important thing to consider since developing nations like INDIA have second highest population, but due to higher cost TDDS are the hidden part of therapy used in general population.
Pathan Maksud; Zikriya Abrar; Quazi Aamer
Today though the oral drug delivery system is dominant still it is found to be need of ideal transdermal drug delivery system. “A micro emulsion is a system of water, oil and an amphiphile which is a single optically isotropic and thermodynamically stable liquid solution”. Microemulsions offer several advantages as drug delivery systems as these are thermodynamically stable and stability allows for self emulsification of the system with microemulsion acting as supersolvent of the drugs which...
S. R. Tajane et al.
The purpose for this review on pulsatile drug delivery systems (PDDS) is to compile the recent literatures with special focus on the different types and approaches involved in the development of the formulation. Pulsatile drug delivery system is the most interesting time and site-specific system. This system is designed for chronopharmacotherapy. Thus, to mimic the function of living systems and in view of emerging chronotherapeutic approaches, pulsatile delivery, which is meant to release a ...
Patel Mitul; Karigar Asif; Savaliya Pratik; Ramana MV; Dubal Ashwini
This review highlights the several advantages of buccal drug delivery system (BDDS) over the conventional and systemic formulation majorly. It helps to enhance bioavailability through bypassing the first pass metabolism. On this drug delivery system the formulation keeps in contact with the mucosal surface resulting in better absorption and prolonged resident time. Though all drugs are not suitable for this drug delivery system yet is useful for most of the drugs. Bioadhesive polymers roles a...
Saahil Arora; Gaurav Bisen; R D Budhiraja
Helicobacter pylori (H. pylori), the major culprit for peptic ulcer, has a unique way of survival in harsh acidic environment of the stomach by colonizing deep in the gastric mucosal layer. Failure of conventional therapies against H. pylori for complete eradication has major limitations like low residence time of delivery system in stomach, poor penetration of drug in gastric mucosa, acidic degradation of antibiotics, and development of antibiotics resistance. The poor penetration of antibio...
Restrepo, Marcos I; Keyt, Holly; Reyes, Luis F
Administration of medications via aerosolization is potentially an ideal strategy to treat airway diseases. This delivery method ensures high concentrations of the medication in the targeted tissues, the airways, with generally lower systemic absorption and systemic adverse effects. Aerosolized antibiotics have been tested as treatment for bacterial infections in patients with cystic fibrosis (CF), non-CF bronchiectasis (NCFB), and ventilator-associated pneumonia (VAP). The most successful application of this to date is treatment of infections in patients with CF. It has been hypothesized that similar success would be seen in NCFB and in difficult-to-treat hospital-acquired infections such as VAP. This review summarizes the available evidence supporting the use of aerosolized antibiotics and addresses the specific considerations that clinicians should recognize when prescribing an aerosolized antibiotic for patients with CF, NCFB, and VAP.
Baelo, Aida; Levato, Riccardo; Julián, Esther; Crespo, Anna; Astola, José; Gavaldà, Joan; Engel, Elisabeth; Mateos-Timoneda, Miguel Angel; Torrents, Eduard
Infections caused by biofilm-forming bacteria are a major threat to hospitalized patients and the main cause of chronic obstructive pulmonary disease and cystic fibrosis. There is an urgent necessity for novel therapeutic approaches, since current antibiotic delivery fails to eliminate biofilm-protected bacteria. In this study, ciprofloxacin-loaded poly(lactic-co-glycolic acid) nanoparticles, which were functionalized with DNase I, were fabricated using a green-solvent based method and their antibiofilm activity was assessed against Pseudomonas aeruginosa biofilms. Such nanoparticles constitute a paradigm shift in biofilm treatment, since, besides releasing ciprofloxacin in a controlled fashion, they are able to target and disassemble the biofilm by degrading the extracellular DNA that stabilize the biofilm matrix. These carriers were compared with free-soluble ciprofloxacin, and ciprofloxacin encapsulated in untreated and poly(lysine)-coated nanoparticles. DNase I-activated nanoparticles were not only able to prevent biofilm formation from planktonic bacteria, but they also successfully reduced established biofilm mass, size and living cell density, as observed in a dynamic environment in a flow cell biofilm assay. Moreover, repeated administration over three days of DNase I-coated nanoparticles encapsulating ciprofloxacin was able to reduce by 95% and then eradicate more than 99.8% of established biofilm, outperforming all the other nanoparticle formulations and the free-drug tested in this study. These promising results, together with minimal cytotoxicity as tested on J774 macrophages, allow obtaining novel antimicrobial nanoparticles, as well as provide clues to design the next generation of drug delivery devices to treat persistent bacterial infections. PMID:25913364
Yalin, Azer; Willson, Bryan; Defoort, Morgan
A spark delivery system for generating a spark using a laser beam is provided, the spark delivery system including a laser light source and a laser delivery assembly. The laser delivery assembly includes a hollow fiber and a launch assembly comprising launch focusing optics to input the laser beam in the hollow fiber. In addition, the laser delivery assembly includes exit focusing optics that demagnify an exit beam of laser light from the hollow fiber, thereby increasing the intensity of the laser beam and creating a spark. In accordance with embodiments of the present invention, the assembly may be used to create a spark in a combustion engine. In accordance with other embodiments of the present invention, a method of using the spark delivery system is provided. In addition, a method of choosing an appropriate fiber for creating a spark using a laser beam is also presented.
Full Text Available Gene therapy is the process of introducing foreign genomic materials into host cells to elicit a therapeutic benefit. Although initially the main focus of gene therapy was on special genetic disorders, now diverse diseases with different patterns of inheritance and acquired diseases are targets of gene therapy. There are 2 major categories of gene therapy, including germline gene therapy and somatic gene therapy. Although germline gene therapy may have great potential, because it is currently ethically forbidden, it cannot be used; however, to date human gene therapy has been limited to somatic cells. Although numerous viral and nonviral gene delivery systems have been developed in the last 3 decades, no delivery system has been designed that can be applied in gene therapy of all kinds of cell types in vitro and in vivo with no limitation and side effects. In this review we explain about the history of gene therapy, all types of gene delivery systems for germline (nuclei, egg cells, embryonic stem cells, pronuclear, microinjection, sperm cells and somatic cells by viral [retroviral, adenoviral, adeno association, helper-dependent adenoviral systems, hybrid adenoviral systems, herpes simplex, pox virus, lentivirus, Epstein-Barr virus] and nonviral systems (physical: Naked DNA, DNA bombardant, electroporation, hydrodynamic, ultrasound, magnetofection and (chemical: Cationic lipids, different cationic polymers, lipid polymers. In addition to the above-mentioned, advantages, disadvantages, and practical use of each system are discussed.
R.R. Bhagwat* and I.S. Vaidhya
Full Text Available ABSTRACT: Evolution of an existing drug molecule from a conventional form to a novel delivery system can significantly improve its performance in terms of patient compliance, safety and efficacy. In the form of a Novel Drug Delivery System an existing drug molecule can get a new life. An appropriately designed Novel Drug Delivery System can be a major advance for solving the problems related towards the release of the drug at specific site with specific rate. The need for delivering drugs to patients efficiently and with fewer side effects has prompted pharmaceutical companies to engage in the development of new drug delivery system. This article covers the basic information regarding Novel Drug Delivery Systems and also different types of the same.
Vidyavati S, Koppisetti
Full Text Available Magnetic drug delivery is a novel approach to delivery drug using engineered ’smart’ micro carriers which appears to overcome a number of limitations facing current methods of delivering medicines. The drug and a suitable ferrofluid are formulated into a pharmaceutically stable formulation which is usually injected through the artery that supplies the target organ or tumor in the presence of an external magnetic field. Depending on the fabrication method, particle size and nature they are named as magnetic microspheres, magnetic nanoparticles, magnetic liposomes etc. This review gives the information regarding the all possible formulations that can be designed using magnetism as the drug delivery mode.
Ravi Kant Upadhyay
Full Text Available Present review highlights various drug delivery systems used for delivery of pharmaceutical agents mainly antibiotics, antineoplastic agents, neuropeptides, and other therapeutic substances through the endothelial capillaries (BBB for CNS therapeutics. In addition, the use of ultrasound in delivery of therapeutic agents/biomolecules such as proline rich peptides, prodrugs, radiopharmaceuticals, proteins, immunoglobulins, and chimeric peptides to the target sites in deep tissue locations inside tumor sites of brain has been explained. In addition, therapeutic applications of various types of nanoparticles such as chitosan based nanomers, dendrimers, carbon nanotubes, niosomes, beta cyclodextrin carriers, cholesterol mediated cationic solid lipid nanoparticles, colloidal drug carriers, liposomes, and micelles have been discussed with their recent advancements. Emphasis has been given on the need of physiological and therapeutic optimization of existing drug delivery methods and their carriers to deliver therapeutic amount of drug into the brain for treatment of various neurological diseases and disorders. Further, strong recommendations are being made to develop nanosized drug carriers/vehicles and noninvasive therapeutic alternatives of conventional methods for better therapeutics of CNS related diseases. Hence, there is an urgent need to design nontoxic biocompatible drugs and develop noninvasive delivery methods to check posttreatment clinical fatalities in neuropatients which occur due to existing highly toxic invasive drugs and treatment methods.
McErlean, Emma M.; McCrudden, Cian M; McCarthy, Helen O.
This chapter examines key concepts with respect to cancer gene therapy and the current issues with respect to non-viral delivery. The biological and molecular barriers that need to be overcome before effective non-viral delivery systems can be appropriately designed for oncology applications are highlighted and ways to overcome these are discussed. Strategies developed to evade the immune response are also described and targeted gene delivery is examined with the most effective strategies hig...
Starch is one of the most abundant and economical renewable biopolymers in nature. Starch molecules are high molecular weight polymers of D-glucose linked by α-(1,4) and α-(1,6) glycosidic bonds, forming linear (amylose) and branched (amylopectin) structures. Octenyl succinic anhydride modified starches (OSA-starch) are designed by carefully choosing a proper starch source, path and degree of modification. This enables emulsion and micro-encapsulation delivery systems for oil based flavors, micronutrients, fragrance, and pharmaceutical actives. A large percentage of flavors are encapsulated by spray drying in today's industry due to its high throughput. However, spray drying encapsulation faces constant challenges with retention of volatile compounds, oxidation of sensitive compound, and manufacturing yield. Specialty OSA-starches were developed suitable for the complex dynamics in spray drying and to provide high encapsulation efficiency and high microcapsule quality. The OSA starch surface activity, low viscosity and film forming capability contribute to high volatile retention and low active oxidation. OSA starches exhibit superior performance, especially in high solids and high oil load encapsulations compared with other hydrocolloids. The submission is based on research and development of Ingredion
Vidyavati S, Koppisetti; Sahiti. B
Magnetic drug delivery is a novel approach to delivery drug using engineered ’smart’ micro carriers which appears to overcome a number of limitations facing current methods of delivering medicines. The drug and a suitable ferrofluid are formulated into a pharmaceutically stable formulation which is usually injected through the artery that supplies the target organ or tumor in the presence of an external magnetic field. Depending on the fabrication method, particle size and nature they are nam...
Joychandra Singh Oinam
Conclusions: Pregnancy is just a natural process (not a disease or a medical condition and external intervention should occur only for sound medical conditions C section delivery cannot replace normal delivery in terms of low maternal mortality and neonatal morbidity and less cost. Prescribing antibiotics to mother of normal delivery may also be avoided if the complete sterilization process during and after the delivery is assured. [Int J Basic Clin Pharmacol 2016; 5(3.000: 794-797
De Pintu Kumar; De, Arnab
Pharmacosome is a potential approach in the vesicular drug delivery system which exhibit several advantages over conventional vesicular drug delivery systems. Pharmacosomes are amphiphilic lipid vesicular system possessing phospholipid complexes of drugs. Drugs bearing active hydrogen atom can be esterified to the lipid. This type of vesicular system improves permeation of drugs across the biomembranes and thus results in an improvement in the bioavailability and can also improve the pharmaco...
Rozenzon, Yan; Trujillo, Robert T.; Beese, Steven C.
One embodiment of the present invention provides a gas-delivery system for delivering reaction gas to a reactor chamber. The gas-delivery system includes a main gas-inlet port for receiving reaction gases and a gas-delivery plate that includes a plurality of gas channels. A gas channel includes a plurality of gas holes for allowing the reaction gases to enter the reactor chamber from the gas channel. The gas-delivery system further includes a plurality of sub-gas lines coupling together the main gas-inlet port and the gas-delivery plate, and a respective sub-gas line is configured to deliver a portion of the received reaction gases to a corresponding gas channel.
Yalin, Azer; Willson, Bryan; Defoort, Morgan; Joshi, Sachin; Reynolds, Adam
A spark delivery system for generating a spark using a laser beam is provided, and includes a laser light source and a laser delivery assembly. The laser delivery assembly includes a hollow fiber and a launch assembly comprising launch focusing optics to input the laser beam in the hollow fiber. The laser delivery assembly further includes exit focusing optics that demagnify an exit beam of laser light from the hollow fiber, thereby increasing the intensity of the laser beam and creating a spark. Other embodiments use a fiber laser to generate a spark. Embodiments of the present invention may be used to create a spark in an engine. Yet other embodiments include collecting light from the spark or a flame resulting from the spark and conveying the light for diagnostics. Methods of using the spark delivery systems and diagnostic systems are provided.
Kidd, Thomas R.; Mendell, Ron
Athletic programs are leisure time delivery systems for the athletes, spectators, and the local community as long as scholarships and extensive media coverage are not involved. College administration should make sure that sports and athletics do not become a delivery sytem for public relations and finance. (CJ)
Dorati, Rossella; DeTrizio, Antonella; Genta, Ida; Grisoli, Pietro; Merelli, Alessia; Tomasi, Corrado; Conti, Bice
The present paper takes into account the DOE application to the preparation process of biodegradable microspheres for osteomyelitis local therapy. With this goal gentamicin loaded polylactide-co-glycolide-copolyethyleneglycol (PLGA-PEG) microspheres were prepared and investigated. Two preparation protocols (o/w and w/o/w) with different process conditions, and three PLGA-PEG block copolymers with different compositions of lactic and glycolic acids and PEG, were tested. A Design Of Experiment (DOE) screening design was applied as an approach to scale up manufacturing step. The results of DOE screening design confirmed that w/o/w technique, the presence of salt and the 15%w/v polymer concentration positively affected the EE% (72.1-97.5%), and span values of particle size distribution (1.03-1.23), while salt addition alone negatively affected the yield process. Process scale up resulted in a decrease of gentamicin EE% that can be attributed to the high volume of water used to remove PVA and NaCl residues. The results of in vitro gentamicin release study show prolonged gentamicin release up to three months from the microspheres prepared with salt addition in the dispersing phase; the behavior being consistent with their highly compact structure highlighted by scanning electron microscopy analysis. The prolonged release of gentamicin is maintained even after embedding the biodegradable microspheres into a thermosetting composite gel made of chitosan and acellular bovine bone matrix (Orthoss® granules), and the microbiologic evaluation demonstrated the efficacy of the gentamicin loaded microspheres on Escherichia coli. The collected results confirm the feasibility of the scale up of microsphere manufacturing process and the high potential of the microparticulate drug delivery system to be used for the local antibiotic delivery to bone. PMID:26478386
Full Text Available Vesicular drug delivery system can be defined as highly ordered assemblies consisting of one or more concentric bilayers formed as a result of self-assembling of amphiphilic building blocks in presence of water. Vesicular drug delivery systems are particularly important for targeted delivery of drugs because of their ability to localize the activity of drug at the site or organ of action thereby lowering its concentration at the other sites in body. Vesicular drug delivery system sustains drug action at a predetermined rate, relatively constant (zero order kinetics, efficient drug level in the body, and simultaneously minimizes the undesirable side effects. It can also localize drug action in the diseased tissue or organ by targeted drug delivery using carriers or chemical derivatization. Different types of pharmaceutical carriers such as polymeric micelles, particulate systems, and macro- and micromolecules are presented in the form of novel drug delivery system for targeted delivery of drugs. Particulate type carrier also known as colloidal carrier system, includes lipid particles, micro- and nanoparticles, micro- and nanospheres, polymeric micelles and vesicular systems like liposomes, sphingosomes, niosomes, transfersomes, aquasomes, ufasomes, and so forth.
Full Text Available The removal of chlorofluorocarbon (CFC propellants from industrial and household products has been agreed to by over 165 countires of which more than 135 are developing countries. The timetable for this process is outlined in the Montreal Protocol on Substances that Deplete the Ozone Layer document and in several subsequent amendments. Pressured metered dose inhalers (pMDIs for medical use have been granted temporary exemptions until replacement formulations, providing the same medication via the same route, and with the same efficacy and safety profiles, are approved for human use. Hydrofluoroalkanes (HFAs are the alternative propellants for CFCs-12 and -114. Their potential for damage to the ozone layer is nonexistent, and while they are greenhouse gases, their global warming potential is a fraction (one-tenth of that of CFCs. Replacement formulations for almost all inhalant respiratory medications have been or are being produced and tested; in Canada, it is anticipated that the transition to these HFA or CFC-free pMDIs will be complete by the year 2005. Initially, an HFA pMDI was to be equivalent to the CFC pMDI being replaced, in terms of aerosol properties and effective clinical dose. However, this will not necessarily be the situation, particularly for some corticosteroid products. Currently, only one CFC-free formulation is available in Canada – Airomir, a HFA salbutamol pMDI. This paper discusses the in vitro aerosol characteristics, in vivo deposition and clinical data for several HFA pMDIs for which there are data available in the literature. Alternative delivery systems to the pMDI, namely, dry powder inhalers and nebulizers, are briefly reviewed.
Cheng, Weixiao; Li, Jianan; Wu, Ying; Xu, Like; Su, Chao; Qian, Yanyun; Zhu, Yong-Guan; Chen, Hong
This study aims to determine abundance and persistence of antibiotics and antibiotic resistance genes (ARGs) in eco-agricultural system (EAS), which starts from swine feces to anaerobic digestion products, then application of anaerobic digestion solid residue (ADSR) and anaerobic digestion liquid residue (ADLR) to the soil to grow ryegrass, one of swine feed. Oxytetracycline had the highest concentration in manure reaching up to 138.7 mg/kg. Most of antibiotics could be effectively eliminated by anaerobic digestion and removal rates ranged from 11% to 86%. ARGs abundance fluctuated within EAS. TetQ had the highest relative abundance and the relative abundance of tetG had the least variation within the system, which indicates that tetG is persistent in the agricultural environment and requires more attention. Compared to the relative abundance in manure, tetC and tetM increased in biogas residue while three ribosomal protection proteins genes (tetO, tetQ, tetW) decreased (p0.05). Most ARGs in downstream components (soils and fishpond) of EAS showed significantly higher relative abundance than the control agricultural system (p<0.05), except for tetG and sulI.
Full Text Available IN recent years several advancement has been made in research and development of Oral Drug Delivery System. Concept of Novel Drug Delivery System arose to overcome the certain aspect related to physicochemical properties of drug molecule and the related formulations. Purpose of this review is to compile the recent literature with special focus on various gastro retentive approaches that have recently become leading methodologies in the field of site-specific orally administered controlled release drug delivery. Technological attempts have been made in the research and development of ratecontrolled oral drug delivery systems to overcome physiological adversities, such as short gastric residence times (GRT and unpredictable gastric emptying times (GET. Therefore, gastro retentive drug delivery systems (GRDDS have been developed, which prolong the gastric emptying time. Several techniques such as floating drug delivery system, low density systems, raft systems, mucoadhesive systems, high density systems, super porous hydro gels and magnetic systems, have been employed. This review on GRDDS attempts to compile the available information with all the possible mechanism used to achieve gastric retention.
Jamil Faraz; Singh Arjun; Kumar Sunil; Sharma Ritika
The purpose for this review on pulsatile drug delivery systems (PDDS) is to compile the recent literatures with special focus on the different types and approaches involved in the development of the formulation. Pulsatile drug delivery system is the most interesting time and site-specific system. Diseases wherein PDDS are promising include asthma, peptic ulcer, cardiovascular diseases, arthritis,attention deficit syndrome in children, and hypercholesterolemia. PDDS can be classified into time...
Full Text Available The recent scientific and patented literature concluded that an increased interest in novel dosage forms which retained in the stomach for prolong and predictable period of time has been shown. Various technological attempts have been made in the research and development of rate-controlled oral drug delivery systems to overcome physiological diversities, as short gastric residence times and unpredictable gastric emptying times using gastro retentive drug delivery system. It is a well known fact that differences in gastric physiology, such as, gastric pH and motility exhibit both intra as well as inter-subject variability demonstrating significant impact on gastric retention time and drug delivery behavior. Various attempts have been made to develop Gastro retentive delivery systems. Several approaches are currently utilized in the prolongation of the GRT, including floating drug delivery systems, swelling and expanding systems, polymeric bio adhesive systems, high-density systems, modified-shape systems and other delayed gastric emptying devices. Floating dosage forms are emerging as a promising dosage forms. Floating dosage form can be prepared as tablets, capsules by adding suitable ingredients as well as by adding gas generating agent. In this review various techniques used in floating dosage forms along with current & recent developments of stomach specific floating drug delivery system for gastro retention are discussed.
Handrock, J.L.; Wally, K.; Raber, T.N. [Sandia National Labs., Livermore, CA (United States)
Hydrogen storage and delivery is an important element in effective hydrogen utilization for energy applications and is an important part of the FY1994-1998 Hydrogen Program Implementation Plan. The purpose of this project is to develop a platform for the engineering evaluation of hydrogen storage and delivery systems with an added focus on lightweight hydride utilization. Hybrid vehicles represent the primary application area of interest, with secondary interests including such items as existing vehicles and stationary uses. The near term goal is the demonstration of an internal combustion engine/storage/delivery subsystem. The long term goal is optimization of storage technologies for both vehicular and industrial stationary uses. In this project an integrated approach is being used to couple system operating characteristics to hardware development. A model has been developed which integrates engine and storage material characteristics into the design of hydride storage and delivery systems. By specifying engine operating parameters, as well as a variety of storage/delivery design features, hydride bed sizing calculations are completed. The model allows engineering trade-off studies to be completed on various hydride material/delivery system configurations. A more generalized model is also being developed to allow the performance characteristics of various hydrogen storage and delivery systems to be compared (liquid, activated carbon, etc.). Many of the features of the hydride storage model are applicable to the development of this more generalized model.
Kim, Y C; Jarrahian, C; Zehrung, D; Mitragotri, S; Prausnitz, M R
Intradermal (ID) vaccination can offer improved immunity and simpler logistics of delivery, but its use in medicine is limited by the need for simple, reliable methods of ID delivery. ID injection by the Mantoux technique requires special training and may not reliably target skin, but is nonetheless used currently for BCG and rabies vaccination. Scarification using a bifurcated needle was extensively used for smallpox eradication, but provides variable and inefficient delivery into the skin. Recently, ID vaccination has been simplified by introduction of a simple-to-use hollow microneedle that has been approved for ID injection of influenza vaccine in Europe. Various designs of hollow microneedles have been studied preclinically and in humans. Vaccines can also be injected into skin using needle-free devices, such as jet injection, which is receiving renewed clinical attention for ID vaccination. Projectile delivery using powder and gold particles (i.e., gene gun) have also been used clinically for ID vaccination. Building off the scarification approach, a number of preclinical studies have examined solid microneedle patches for use with vaccine coated onto metal microneedles, encapsulated within dissolving microneedles or added topically to skin after microneedle pretreatment, as well as adapting tattoo guns for ID vaccination. Finally, technologies designed to increase skin permeability in combination with a vaccine patch have been studied through the use of skin abrasion, ultrasound, electroporation, chemical enhancers, and thermal ablation. The prospects for bringing ID vaccination into more widespread clinical practice are encouraging, given the large number of technologies for ID delivery under development. PMID:21472533
Patel Harshna; Solanki N S
IN recent years several advancement has been made in research and development of Oral Drug Delivery System. Concept of Novel Drug Delivery System arose to overcome the certain aspect related to physicochemical properties of drug molecule and the related formulations. Purpose of this review is to compile the recent literature with special focus on various gastro retentive approaches that have recently become leading methodologies in the field of site-specific orally administered controlled rel...
Kataria Sahil; Middha Akanksha; Bhardwaj Sudeep; Sandhu Premjeet
The recent scientific and patented literature concluded that an increased interest in novel dosage forms which retained in the stomach for prolong and predictable period of time has been shown. Various technological attempts have been made in the research and development of rate-controlled oral drug delivery systems to overcome physiological diversities, as short gastric residence times and unpredictable gastric emptying times using gastro retentive drug delivery system. It is a well known fa...
Bhawandeep Gill; Jatinder Singh; Vikas Sharma; S L Hari Kumar
The oral route is the easiest, cost effective, and most vital method for drug administration. Therefore, improvement of dosage forms mainly for the prolonged release purpose has been a challenge for scientists. Vesicular drug delivery systems are developed with a purpose to overcome problems coupled with the drugs such a poor bioavailability, protection from harsh gastric environment, and from gastric enzymes, which degrade the drug. Vesicular drug delivery systems such as liposomes, emulsion...
Harnish Patel; Upendra Patel; Hiren Kadikar; Bhavin Bhimani; Dhiren Daslaniya; Ghanshyam Patel
Conventional oral drug delivery systems supply an instantaneous release of drug, which cannot control the release of the drug and effective concentration at the target site. This kind of dosing pattern may result in constantly changing, unpredictable plasma concentrations. Drugs can be delivered in a controlled pattern over a long period of time by the process of osmosis. Osmotic devices are the most promising strategy based systems for controlled drug delivery. They are the most reliable con...
Sandhu Premjeet; Kataria Sahil; Bilandi Ajay; Jain Sonam; Rathore Devashish
Conventional drug delivery systems are often not suitable for new protein based and other Therapeutic compounds produced by modern technology. Therefore an alternative Approach to deliver these drugs can be achieved through the skin in the form of transcutaneous drug delivery system. Modern medicine has responded with the development of methods to deliver drug transcutanously (through) the skin for therapeutic use as an alternative to traditional route including oral, intravascular, intramusc...
Full Text Available Cyclodextrins (CDs are a family of cyclic oligosaccharides with a hydrophilic outer surface and a lipophilic central cavity. CD molecules are relatively large with a number of hydrogen donors and acceptors and, thus in general, they do not permeate lipophilic membranes. In the pharmaceutical industry, CDs have mainly been used as complexing agents to increase aqueous solubility of poorly soluble drugs and to increase their bioavailability and stability. CDs are used in pharmaceutical applications for numerous purposes, including improving the bioavailability of drugs. Current CD-based therapeutics is described and possible future applications are discussed. CD-containing polymers are reviewed and their use in drug delivery is presented. Of specific interest is the use of CD-containing polymers to provide unique capabilities for the delivery of nucleic acids. Studies in both humans and animals have shown that CDs can be used to improve drug delivery from almost any type of drug formulation. Currently, there are approximately 30 different pharmaceutical products worldwide containing drug/CD complexes in the market.
Full Text Available The purpose for this review on pulsatile drug delivery systems (PDDS is to compile the recent literatures with special focus on the different types and approaches involved in the development of the formulation. Pulsatile drug delivery system is the most interesting time and site-specific system. Diseases wherein PDDS are promising include asthma, peptic ulcer, cardiovascular diseases, arthritis,attention deficit syndrome in children, and hypercholesterolemia. PDDS can be classified into time controlled systems wherein the drug release is controlled primarily by the delivery system; stimuli induced PDDS in which release is controlled by the stimuli, like the pH or enzymes present in the Intestinal tract or enzymes present in the drug delivery system and externally regulated system where release is programmed by external stimuli like magnetism, ultrasound, electrical effect and irradiation. Marketed product like Pulsicap®, Ritalin® and Pulsys® are based on pulsatile release system. The aim of this review is to describe several types of drug delivery systems. This review also summarizes some current PDDS already available in the market. These systems are useful to several problems encountered during the development of a pharmaceutical dosage form.
Rennig, Maja; Nørholm, Morten
Introduction: Protein overproduction is a major bottleneck for analyses of membrane proteins and for the construction of cell factories. Screening for optimized protein production can be very time consuming. In this study we show that the coupling of antibiotic resistance to poorly produced...... membrane proteins of Escherichia coli can be used as a fast and simple selection system for protein overproduction.Methods: We designed an expression plasmid encoding the gene of interest and an additional, inducible antibiotic resistance marker. Both genes were linked by a hairpin structure...... that translationally couples the genes. Consequently, high expressing gene variants also allow for higher production of the coupled antibiotic resistance marker. Therefore, high expressing gene variants in a library can be determined either by plating the expression library on selection plates or by growing...
Studies on antibiotics, oxytetracycline (OxyTC) in particular, are presented in this thesis with respect to the influence of these drugs on the immune system of carp and chickens. Special attention was paid to the pharmacokinetic behaviour of OxyTC.ImmunologyCarp ( Cyprinusca
Full Text Available In recent years scientific and technological advancements have been made in the research and development of oral drug delivery system. Oral sustained drug delivery system is complicated by limited gastric residence times (GRTs. In order to understand various physiological difficulties to achieve gastric retention, we have summarized important factors controlling gastric retention. To overcome these limitations, various approaches have been proposed to increase gastric residence of drug delivery systems in the upper part of the gastrointestinal tract includes floating drug dosage systems (FDDS, swelling or expanding systems , mucoadhesive systems , magnetic systems, modified-shape systems, high density system and other delayed gastric emptying devices.
Full Text Available The oral route is the easiest, cost effective, and most vital method for drug administration. Therefore, improvement of dosage forms mainly for the prolonged release purpose has been a challenge for scientists. Vesicular drug delivery systems are developed with a purpose to overcome problems coupled with the drugs such a poor bioavailability, protection from harsh gastric environment, and from gastric enzymes, which degrade the drug. Vesicular drug delivery systems such as liposomes, emulsions, niosomes, proniosomes, solid lipid-nano particles, ethosomes, nanoparticles, and pharmacosomes, etc have gained much attention, but emulsomes have rouse as system, which bypasses many disadvantages associated with other systems, developed as novel lipoidal vesicular system with internal solid fat core surrounded by phospholipid bilayer. This technology is designed to act as vehicle for poorly soluble drugs. The drug is enclosed in the emulsomes and provide prolong existence of drug in systemic circulation. Furthermore, emulsomal-based formulations of genetic drugs such as antisense oligonucleotides and plasmids for gene therapy that have clear potential for systemic utility are increasingly available. This review addresses the concept of emulsomal drug delivery system, summarizes the success of emulsomes for the delivery of small molecules, and special attention has been paid to its formulation design, advantages, biopharmaceutical aspects, stability aspects, and various aspects related to drug delivery including future aspects.
Full Text Available Controlled release local drug delivery systems offer advantages compared to systemic dosage forms for many dental diseases like gingivitis, periodontitis. The objective of this literature survey was to gain knowledge about various dental drug delivery systems for targeted delivery of the drug. The polymer ethyl cellulose was used in the formulation of dental films. The dental film was then evaluated for various parameters like thickness, folding endurance and weight variation and content uniformity, in vitro and in vivo study. There has been a great attention in using iontophoretic technique for the transdermal drug delivery of medications, both ionic and non ionic. This technique of facilitated movement of ions across a membrane under the influence of an externally applied electric potential difference is one of the most promising physical skin penetrations enhancing method. Another novel approach is the use of lasers in dentistry. Lasers can be used in both hard and soft tissue applications including laser bleaching, frenectomy, gingivectomy, caries removal etc. Drugs delivery via the buccal routs using bio adhesive dosage forms offers such a novel route of drugs administration. This route has been used successfully for the systematic delivery of number of drugs candidates. Problems such as high first pass metabolisms and drugs degradation in the gastrointestinal tract can be circumvented by administrating the drug buccal routes.
S. R. Tajane et al.
Full Text Available The purpose for this review on pulsatile drug delivery systems (PDDS is to compile the recent literatures with special focus on the different types and approaches involved in the development of the formulation. Pulsatile drug delivery system is the most interesting time and site-specific system. This system is designed for chronopharmacotherapy. Thus, to mimic the function of living systems and in view of emerging chronotherapeutic approaches, pulsatile delivery, which is meant to release a drug following programmed lag phase, has increasing interest in the recent years. Diseases wherein PDDS are promising include asthma, peptic ulcer, cardiovascular diseases, arthritis, and attention deficit syndrome in children, cancer, diabetes, and hypercholesterolemia. Pulsatile drug delivery system divided into 2 types’ preplanned systems and stimulus induced system, preplanned systems based on osmosis, rupturable layers, and erodible barrier coatings. Stimuli induced system based on electrical, temperature and chemically induced systems. This review also summarizes some current PDDS already available in the market. These systems are useful to several problems encountered during the development of a pharmaceutical dosage form.
Knapp, Stuart E.; Valentine, Carol A.
Extrapolating from the trends in postsecondary instructional delivery systems identified by Brown, Lewis and Harcleroad, this report attempts to identify how these trends might be implemented in Oregon. Separating the systems into technology-centered and people-centered, the report proposes future applications of dial access systems, self learning…
Shikha Deshwal et al
Full Text Available Transdermal drug technology specialists are continuing to search for new methods that can effectively and painlessly deliver larger molecules in therapeutic quantities to overcome the difficulties associated with the oral route. Transdermal Drug Delivery System (TDDS is the system in which the delivery of the active ingredients of the drug occurs by the means of skin. Skin is an effective medium from which absorption of the drug takes place and enters in to circulatory system. Various types of transdermal patches are used to incorporate the active ingredients into the circulatory system via skin. The patches have been proved effective because of its large advantages over other controlled drug delivery systems. This review article covers a brief outline of various components of transdermal patch, applications of transdermal patch, their advantages, disadvantages, when the transdermal patch are used and when their use should be avoided, types of transdermal patch, recent techniques for enhancing TDDS
Full Text Available Today though the oral drug delivery system is dominant still it is found to be need of ideal transdermal drug delivery system. “A micro emulsion is a system of water, oil and an amphiphile which is a single optically isotropic and thermodynamically stable liquid solution”. Microemulsions offer several advantages as drug delivery systems as these are thermodynamically stable and stability allows for self emulsification of the system with microemulsion acting as supersolvent of the drugs which are poorly or insoluble in water. They are preferred more as compared to conventional emulsions due stability. The dispersed phase mainly acts as the solvent for the water insoluble drug. Microemulsions have been proved to increase the cutaneous absorption of both lipophilic and hydrophilic API’s when compared to conventional vehicles.
Full Text Available Pulsatile systems are gaining a lot of interest as they deliver the drug at the right site of action at the right time and in the right amount, thus providing spatial and temporal delivery and increasing patient compliance. These systems are designed according to the circadian rhythm of the body. The principle rationale for the use of pulsatile release is for the drugs where a constant drug release, i.e., a zero-order release is not desired. The release of the drug as a pulse after a lag time has to be designed in such a way that a complete and rapid drug release follows the lag time. Various systems like capsular systems, osmotic systems, single- and multiple-unit systems based on the use of soluble or erodible polymer coating and use of rupturable membranes have been dealt with in the article. It summarizes the latest technological developments, formulation parameters, and release profiles of these systems. Products available as once-a-daily formulation based on Pulsatile release like Pulsincap ®, Ritalin ®, and Pulsys ® are also covered in the review. These systems are beneficial for the drugs having chronopharmacological behaviour where night time dosing is required and for the drugs having high first-pass effect and having specific site of absorption in GIT. Drugs used in asthmatic patients and patients suffering from rheumatoid arthritis are also discussed along with many other examples.
Full Text Available The structure of DNA was unraveled by Watson and Crick in 1953, and two decades later Arber, Nathans and Smith discovered DNA restriction enzymes, which led to the rapid growth in the field of recombinant DNA technology. From expressing cloned genes in bacteria to expressing foreign DNA in transgenic animals, DNA is now slated to be used as a therapeutic agent to replace defective genes in patients suffering from genetic disorders or to kill tumor cells in cancer patients. Gene therapy provides modern medicine with new perspectives that were unthinkable two decades ago. Progress in molecular biology and especially, molecular medicine is now changing the basics of clinical medicine. A variety of viral and non-viral possibilities are available for basic and clinical research. This review summarizes the delivery routes and methods for gene transfer used in gene therapy.
Full Text Available Aerial Delivery Research & Development Establishment (ADRDE was started at Kanpur during latter part of 1950's consisting of two Aerial Delivery Sections primarily for the indigenisation of Parachutes and related equipment for Para-dropping of men and materials. Today, the charter of ADRDE includes design & development of parachutes, Aerostat Systems, Aircraft Arrester Barrier Systems and Heavy-Drop Systems for both military and civilian applications. The technological competence built in Aeronautical, Textile, Mechanical and Electronics engineering has imparted ADRDE, a unique combination of know-how and capabilities to evolve new solutions in these fields, with emphasis on quality assurance. This paper highlights the design and development of technologies developed by ADRDE to stengthen the India's aerial delivery system and its future plans.Defence Science Journal, 2010, 60(2, pp.124-136, DOI:http://dx.doi.org/10.14429/dsj.60.326
Brogan, David M; Mossialos, Elias
Over the past decade, there has been a growing recognition of the increasing growth of antibiotic resistant bacteria and a relative decline in the production of novel antibacterial therapies. The combination of these two forces poses a potentially grave threat to global health, in both developed and developing countries. Current market forces do not provide appropriate incentives to stimulate new antibiotic development, thus we propose a new incentive mechanism: the Options Market for Antibiotics. This mechanism, modelled on the principle of financial call options, allows payers to buy the right, in early stages of development, to purchase antibiotics at a discounted price if and when they ever make it to market approval. This paper demonstrates the effect of such a model on the expected Net Present Value of a typical antibacterial project. As part of an integrated strategy to confront the impending antibiotic crisis, the Options Market for Antibiotics may effectively stimulate corporate and public investment into antibiotic research and development. PMID:26808335
Brogan, David M; Mossialos, Elias
Over the past decade, there has been a growing recognition of the increasing growth of antibiotic resistant bacteria and a relative decline in the production of novel antibacterial therapies. The combination of these two forces poses a potentially grave threat to global health, in both developed and developing countries. Current market forces do not provide appropriate incentives to stimulate new antibiotic development, thus we propose a new incentive mechanism: the Options Market for Antibiotics. This mechanism, modelled on the principle of financial call options, allows payers to buy the right, in early stages of development, to purchase antibiotics at a discounted price if and when they ever make it to market approval. This paper demonstrates the effect of such a model on the expected Net Present Value of a typical antibacterial project. As part of an integrated strategy to confront the impending antibiotic crisis, the Options Market for Antibiotics may effectively stimulate corporate and public investment into antibiotic research and development.
D. Nagasamy Venkatesh
Full Text Available Lipid based drug delivery systems have been examined in various studies and exhibited their potential in controlled and targeted drug delivery. Pharmacosomes, a novel vesicular drug delivery system, offering a unique advantage over liposomes and niosomes, and serve as potential alternative to these conventional vesicles. They constitute an amphiphilic phospholipid complex with drug bearing an active hydrogen atom covalently that bind to phospholipids. They provide an efficient delivery of drug required at the site of action, which ultimately reduces the drug toxicity with reduced adverse effects and also reduces the cost of therapy by imparting better biopharmaceutical properties to the drug, resulting in increases bioavailability, especially in case of poorly soluble drugs. As the system is formed by binding the drug (pharmakon to carrier (soma, they are termed as pharmacosomes. Depending upon the chemical structure of the drug lipid complex they may exist as ultrafine vesicular, micellar and hexagonal aggregate. Drug having active hydrogen group such as carboxyl, hydroxyl group can be esterified to lipids, resulting in amphiphilic compound. Pharmacosomes are widely used as carriers for various non-steroidal anti-inflammatory drugs, proteins, cardiovascular and antineoplastic drugs. The release of drug from pharmacosomes is generally governed by the process of enzymatic reaction and acid hydrolysis. Here, in the present review paper we have discussed the potential of pharmacosomes as a controlled and targeted drug delivery system and highlighted the method of preparation and characterization.
SERVIR, an automated document delivery system developed by CIN/CNEN, is described. Parametric procedures for reading bibliographic data bases and requesting documents from libraries through computer are specified. Statistical procedures, accounting system and the on-line fulfillment of requests are presented. (Author)
Full Text Available The purpose of writing this review on the floating drug delivery systems (FDDS was to compile the recent literature with special focus on the principal mechanism of floatation to achieve gastric retention. FDDS is one of the approaches in chronotherapeutic drug delivery. In the past reviews of FDDS the physiological and formulation variables affecting gastric retention, approaches to design single-unit and multiple-unit floating systems, their classification and formulation aspects have been covered. This review summarizes the special focus on chronotherapeutics, diseases affected by biological rhythm, its importance, advantages, various approaches in Chronotherapeutic drug delivery and applications of FDDS. These systems are useful for several problems encountered during the development of a pharmaceutical dosage forms.
Full Text Available Abstract Nanoparticles hold tremendous potential as an effective drug delivery system. In this review we discussed recent developments in nanotechnology for drug delivery. To overcome the problems of gene and drug delivery, nanotechnology has gained interest in recent years. Nanosystems with different compositions and biological properties have been extensively investigated for drug and gene delivery applications. To achieve efficient drug delivery it is important to understand the interactions of nanomaterials with the biological environment, targeting cell-surface receptors, drug release, multiple drug administration, stability of therapeutic agents and molecular mechanisms of cell signalling involved in pathobiology of the disease under consideration. Several anti-cancer drugs including paclitaxel, doxorubicin, 5-fluorouracil and dexamethasone have been successfully formulated using nanomaterials. Quantom dots, chitosan, Polylactic/glycolic acid (PLGA and PLGA-based nanoparticles have also been used for in vitro RNAi delivery. Brain cancer is one of the most difficult malignancies to detect and treat mainly because of the difficulty in getting imaging and therapeutic agents past the blood-brain barrier and into the brain. Anti-cancer drugs such as loperamide and doxorubicin bound to nanomaterials have been shown to cross the intact blood-brain barrier and released at therapeutic concentrations in the brain. The use of nanomaterials including peptide-based nanotubes to target the vascular endothelial growth factor (VEGF receptor and cell adhesion molecules like integrins, cadherins and selectins, is a new approach to control disease progression.
Shyam Sunder Mandava et al.
Full Text Available Transdermal drug delivery system (TDS is not practically for delivery of materials whose final target is skin itself. Application topical agents generally offer many problems such as rashes, skin irritancy and burning sensation etc due to higher percutaneous absorption of drugs on the skin. Some conventional dosage e.g., gels and ointments. Which are often aesthetically unappealing, greasiness and stickiness etc. that often result into lack of patient compliance. For reduce this side effects, microsponge technology offers many advantage over the conventional drug delivery. The microsponge based drug delivery system is a unique technology for controlled release and enhanced drug deposition in the skin while minimizing transdermal penetration of topically active agents. Drug loaded microsponge consist of microporous beads, typically 10-25 μm in diameter. Microsponge delivery system (MDS can provide increased efficacy for topically active agents with enhanced safety, extended product stability, enhanced formulation flexibility, reduced side effects and improved aesthetic properties in an efficient and novel manner. In addition these are non-irritating, non-allergenic, non-mutagenic, and non-toxic. MDS technology is being used currently in cosmetics, over-the-counter skin care, sunscreen and prescription products.
Garbayo, E; Ansorena, E; Blanco-Prieto, M J
Neurodegenerative disorders (NDs) are rapidly increasing as population ages. However, successful treatments for NDs have so far been limited and drug delivery to the brain remains one of the major challenges to overcome. There has recently been growing interest in the development of drug delivery systems (DDS) for local or systemic brain administration. DDS are able to improve the pharmacological and therapeutic properties of conventional drugs and reduce their side effects. The present review provides a concise overview of the recent advances made in the field of brain drug delivery for treating neurodegenerative disorders. Examples include polymeric micro and nanoparticles, lipidic nanoparticles, pegylated liposomes, microemulsions and nanogels that have been tested in experimental models of Parkinson's, Alzheimer's and Huntington's disease. Overall, the results reviewed here show that DDS have great potential for NDs treatment. PMID:23016644
Innocent J. Macha
Full Text Available Hydrothermally converted coralline hydroxyapatite (HAp particles loaded with medically active substances were used to develop polylactic acid (PLA thin film composites for slow drug delivery systems. The effects of HAp particles within PLA matrix on the gentamicin (GM release and release kinetics were studied. The gentamicin release kinetics seemed to follow Power law Korsmeyer Peppas model with mainly diffusional process with a number of different drug transport mechanisms. Statistical analysis shows very significant difference on the release of gentamicin between GM containing PLA (PLAGM and GM containing HAp microspheres within PLA matrix (PLAHApGM devices, which PLAHApGM displays lower release rates. The use of HAp particles improved drug stabilization and higher drug encapsulation efficiency of the carrier. HAp is also the source of Ca2+ for the regeneration and repair of diseased bone tissue. The release profiles, exhibited a steady state release rate with significant antimicrobial activity against Staphylococcus aureus (S. aureus (SH1000 even at high concentration of bacteria. The devices also indicated significant ability to control the growth of bacterial even after four weeks of drug release. Clinical release profiles can be easily tuned from drug-HAp physicochemical interactions and degradation kinetics of polymer matrix. The developed systems could be applied to prevent microbial adhesion to medical implant surfaces and to treat infections mainly caused by S. aureus in surgery.
Patel DS; Patel MV; Patel KN; Patel BA; Patel PA
Today about 70% of drugs are taken orally and are found not to be as effective as desired. To improvesuch characters transdermal drug delivery system was emerged. Transdermal drug delivery system(TDDS) provides a means to sustain drug release as well as reduce the intensity of action and thusreduce the side effects associated with its oral therapy and differs from traditional topical drug delivery.Transdermal Drug Delivery System is the system in which the delivery of the active ingredients o...
Arundhati Bhattacharyya; Meenakshi Bajpai
Amphotericin B is a polyene antifungal antibiotic belonging to Class IV of Biopharmaceutics Classification System which is not absorbed from the gastrointestinal tract after oral administration. The aim of this research work was to develop a self-emulsifying drug delivery system (SEDDS) of amphotericin B and to evaluate the dissolution and permeability of amphotericin B from the formulation. The solubility of amphotericin B in various oils, surfactants and cosurfactants was determined. Variou...
Full Text Available Drug delivered can have significant effect on its efficacy. Some drugs have an optimum concentration range with in which maximum benefit is derived and concentrations above (or below the range can be toxic or produce no therapeutic effect. Various drug delivery and drug targeting systems are currently under development. The main goal for developing such delivery systems is to minimize drug degradation and loss, to prevent harmful side effects and to increase bioavailability. Targeting is the ability to direct the drug loaded system to the site of interest. Among drug carrier one can name soluble polymers, microparticles made of insoluble (or biodegradable natural and synthetic polymers, microcapsules, cells, cell ghosts, lipoproteins, liposomes and micelles. Two major mechanisms can be distinguished for addressing the desired sites for drug release, (a Passive and (b Active targeting. Controlled drug carrier systems such as micellar solutions, vescicles and liquid crystal dispersions, as well as nanoparticle dispersions consisting of small particles of 10 – 400 nm show great promise as drug delivery systems. Hydrogels are three dimensional, hydrophilic, polymer networks capable of imbibing large amounts of water or biological fluids. Buckyballs, a novel delivery system with 60 carbon atoms formed in the shape of hollow ball. They are other type’s namely bucky babies, fuzzy balls, gadofullereness, and giant fullerenes. Nanoparticles can be classified as nano tubes, nano wires, nano cantilever, nanoshells, quantum dots, nano pores. Researchers at north western university using gold particles to develop ultra sensitive detection systems for DNA and protein markers associated with many forms of cancer, including breast and prostrate cancer. Drug loaded erythrocytes is one of the growing and potential systems for delivery of drugs and enzymes.
Kluin, Otto S.; van der Mei, Henny C.; Busscher, Henk J.; Neut, Danielle
Introduction: Chronic osteomyelitis, or bone infection, is a major worldwide cause of morbidity and mortality, as it is exceptionally hard to treat due to patient and pathogen-associated factors. Successful treatment requires surgical debridement together with long-term, high antibiotic concentratio
This document provides a documented basis for the required design pressure rating and pump pressure capacity of the Hanford Site waste-transfer system in support of the waste feed delivery to the privatization contractor for vitrification. The scope of the analysis includes the 200 East Area double-shell tank waste transfer pipeline system and the associated transfer system pumps for a11 Phase 1B and Phase 2 waste transfers from AN, AP, AW, AY, and A2 Tank Farms.
De Pintu Kumar
Full Text Available Pharmacosome is a potential approach in the vesicular drug delivery system which exhibit several advantages over conventional vesicular drug delivery systems. Pharmacosomes are amphiphilic lipid vesicular system possessing phospholipid complexes of drugs. Drugs bearing active hydrogen atom can be esterified to the lipid. This type of vesicular system improves permeation of drugs across the biomembranes and thus results in an improvement in the bioavailability and can also improve the pharmacokinetic and pharmacodynamic properties of various types of drug molecules.This vesicular system can be characterized by surface morphology, solubility study, differential scanning calorimrtry, x-ray powder diffraction, in vitro dissolution study. Pharmacosomes are suitable for incorporating both hydrophilic and lipophilic drugs.Preparations of pharmacosomes are basically performed for various non-steroidal anti-inflammatory drugs, proteins, cardiovascular and antineoplastic drugs.
Deepak Sharma et al
Full Text Available Mucoadhesion is a field of current interest in the design of drug delivery systems. Mucoadhesion is commonly defined as the adhesion between two materials, at least one of which is a mucosal surface. Mucoadhesive drug delivery system may be designed to enable prolonged residence time of the dosage form at the site of application or absorption and facilitate an intimate contact of the dosage form with the underline absorption surface. Extending the residence time of a dosage form at a particular site and controlling the release of drug from the dosage form are useful especially for achieving controlled plasma level of the drug as well as improving bioavailability. Application of these dosage forms to mucosal surfaces may be of benefit to drug molecules not amenable to the oral route, such as those that undergo acid degradation or extensive first-pass metabolism. The present review describes mucoadhesion, mucoadhesive polymers and use of these polymers in designing different types of mucoadhesive gastrointestinal, nasal, ocular, vaginal and rectal drug delivery systems. The research on mucoadhesives, however, is still in its early stage, and further advances need to be made for the successful translation of the concept into practical application in controlled drug delivery.
Qiu, Yuqin; Li, Chun; Zhang, Suohui; Yang, Guozhong; He, Meilin; Gao, Yunhua
Dissolving microneedles (DMNs) based transdermal delivery is an attractive drug delivery approach with minimal invasion. However, it is still challenging to load poorly water-soluble drugs in DMNs for systemic delivery. The aim of the study was to develop DMNs loaded with artemether (ARM) as a model drug, to enable efficient drug penetration through skin for systemic absorption and distribution. The micro-conduits created by microneedles were imaged by confocal laser scanning microscopy (CLSM), and the insertion depth was suggested to be about 270μm. The maximum amount of ARM delivered into skin was 72.67±2.69% of the initial dose loaded on DMNs preparation. Pharmacokinetics study in rats indicated a dose-dependent profile of plasma ARM concentrations, after ARM-loaded DMNs treatment. In contrast to intramuscular injection, DMNs application resulted in lower peak plasma levels, but higher plasma ARM concentration at 8h after administration. There were no significant difference in area under the curve and bioavailability between DMNs group and intramuscular group (P>0.05). Pharmacodynamics studies performed in collagen-induced arthritis (CIA) rats showed that ARM-loaded DMNs could reverse paw edema, similar to ARM intramuscular injection. In conclusion, developed DMNs provided a potential minimally invasive route for systemic delivery of poorly water-soluble drugs. PMID:27150946
Sandoval-Motta, Santiago; Aldana, Maximino
Despite all the major breakthroughs in antibiotic development and treatment procedures, there is still no long-term solution to the bacterial antibiotic resistance problem. Among all the known types of resistance, adaptive resistance (AdR) is particularly inconvenient. This phenotype is known to emerge as a consequence of concentration gradients, as well as contact with subinhibitory concentrations of antibiotics, both known to occur in human patients and livestock. Moreover, AdR has been repeatedly correlated with the appearance of multidrug resistance, although the biological processes behind its emergence and evolution are not well understood. Epigenetic inheritance, population structure and heterogeneity, high mutation rates, gene amplification, efflux pumps, and biofilm formation have all been reported as possible explanations for its development. Nonetheless, these concepts taken independently have not been sufficient to prevent AdR's fast emergence or to predict its low stability. New strains of resistant pathogens continue to appear, and none of the new approaches used to kill them (mixed antibiotics, sequential treatments, and efflux inhibitors) are completely efficient. With the advent of systems biology and its toolsets, integrative models that combine experimentally known features with computational simulations have significantly improved our understanding of the emergence and evolution of the adaptive-resistant phenotype. Apart from outlining these findings, we propose that one of the main cornerstones of AdR in bacteria, is the conjunction of two types of mechanisms: one rapidly responding to transient environmental challenges but not very efficient, and another much more effective and specific, but developing on longer time scales. WIREs Syst Biol Med 2016, 8:253-267. doi: 10.1002/wsbm.1335 For further resources related to this article, please visit the WIREs website. PMID:27103502
Sandoval-Motta, Santiago; Aldana, Maximino
Despite all the major breakthroughs in antibiotic development and treatment procedures, there is still no long-term solution to the bacterial antibiotic resistance problem. Among all the known types of resistance, adaptive resistance (AdR) is particularly inconvenient. This phenotype is known to emerge as a consequence of concentration gradients, as well as contact with subinhibitory concentrations of antibiotics, both known to occur in human patients and livestock. Moreover, AdR has been repeatedly correlated with the appearance of multidrug resistance, although the biological processes behind its emergence and evolution are not well understood. Epigenetic inheritance, population structure and heterogeneity, high mutation rates, gene amplification, efflux pumps, and biofilm formation have all been reported as possible explanations for its development. Nonetheless, these concepts taken independently have not been sufficient to prevent AdR's fast emergence or to predict its low stability. New strains of resistant pathogens continue to appear, and none of the new approaches used to kill them (mixed antibiotics, sequential treatments, and efflux inhibitors) are completely efficient. With the advent of systems biology and its toolsets, integrative models that combine experimentally known features with computational simulations have significantly improved our understanding of the emergence and evolution of the adaptive-resistant phenotype. Apart from outlining these findings, we propose that one of the main cornerstones of AdR in bacteria, is the conjunction of two types of mechanisms: one rapidly responding to transient environmental challenges but not very efficient, and another much more effective and specific, but developing on longer time scales. WIREs Syst Biol Med 2016, 8:253-267. doi: 10.1002/wsbm.1335 For further resources related to this article, please visit the WIREs website.
Jo, Won-Jun; Baek, Seung-Ki; Park, Jung-Hwan
A wireless actuating drug delivery system was devised. The system is based on induction heating for drug delivery. In this study, thermally generated nitrogen gas produced by induction heating of azobisisobutyronitrile (AIBN) was utilized for pressure-driven release of the drug. The delivery device consists of an actuator chamber, a drug reservoir, and a microchannel. A semicircular copper disc (5 and 6 mm in diameter and 100 µm thick), and thermal conductive tape were integrated as the heating element in the actuator chamber. The final device was 2.7 mm thick. 28 µl of drug solution were placed in the reservoir and the device released the drug quickly at the rate of 6 µl s-1 by induction heating at 160 µT of magnetic intensity. The entire drug solution was released and dispersed after subcutaneous implantation under identical experimental condition. This study demonstrates that the device was simply prepared and drug delivery could be achieved by wireless actuation of a thin, pressure-driven actuator.
A wireless actuating drug delivery system was devised. The system is based on induction heating for drug delivery. In this study, thermally generated nitrogen gas produced by induction heating of azobisisobutyronitrile (AIBN) was utilized for pressure-driven release of the drug. The delivery device consists of an actuator chamber, a drug reservoir, and a microchannel. A semicircular copper disc (5 and 6 mm in diameter and 100 µm thick), and thermal conductive tape were integrated as the heating element in the actuator chamber. The final device was 2.7 mm thick. 28 µl of drug solution were placed in the reservoir and the device released the drug quickly at the rate of 6 µl s−1 by induction heating at 160 µT of magnetic intensity. The entire drug solution was released and dispersed after subcutaneous implantation under identical experimental condition. This study demonstrates that the device was simply prepared and drug delivery could be achieved by wireless actuation of a thin, pressure-driven actuator. (paper)
Bhalla.Neetika; Deep Arsh; Goswami Manish
In recent years scientific and technological advancements have been made in the research and development of oral drug delivery system. Oral sustained drug delivery system is complicated by limited gastric residence times (GRTs). In order to understand various physiological difficulties to achieve gastric retention, we have summarized important factors controlling gastric retention. To overcome these limitations, various approaches have been proposed to increase gastric residence of drug deli...
Handrock, J.L.; Malinowski, M.E.; Wally, K. [Sandia National Lab., Livermore, CA (United States)
Hydrogen storage and delivery is an important element in effective hydrogen utilization for energy applications and is an important part of the FY1994-1998 Hydrogen Program Implementation Plan. This project is part of the Field Work Proposal entitled Hydrogen Utilization in Internal Combustion Engines (ICE). The goal of the Hydrogen Storage and Delivery System Development Project is to expand the state-of-the-art of hydrogen storage and delivery system design and development. At the foundation of this activity is the development of both analytical and experimental evaluation platforms. These tools provide the basis for an integrated approach for coupling hydrogen storage and delivery technology to the operating characteristics of potential hydrogen energy use applications. Analytical models have been developed for internal combustion engine (ICE) hybrid and fuel cell driven vehicles. The dependence of hydride storage system weight and energy use efficiency on engine brake efficiency and exhaust temperature for ICE hybrid vehicle applications is examined. Results show that while storage system weight decreases with increasing engine brake efficiency energy use efficiency remains relatively unchanged. The development, capability, and use of a newly developed fuel cell vehicle hydride storage system model will also be discussed. As an example of model use power distribution and control for a simulated driving cycle is presented. An experimental test facility, the Hydride Bed Testing Laboratory (HBTL) has been designed and fabricated. The development of this facility and its use in storage system development will be reviewed. These two capabilities (analytical and experimental) form the basis of an integrated approach to storage system design and development. The initial focus of these activities has been on hydride utilization for vehicular applications.
Kharat, Rekha; Bathe, Ritesh Suresh
Transdermal drug delivery system was introduced to overcome the difficulties of drug delivery through oral route. Despite their relatively higher costs, transdermal delivery systems have proved advantageous for delivery of selected drugs, such as estrogens, testosterone, clonidine and nitro-glycerine. Transdermal delivery provides a leading edge over injectable and oral routes by increasing patient compliance and avoiding first pass metabolism respectively. Topical administration of therap...
Handrock, J.L. [Sandia National Labs., Livermore, CA (United States)
Hydrogen storage and delivery is an important element in effective hydrogen utilization for energy applications and is an important part of the FY1994-1998 Hydrogen Program Implementation Plan. This project is part of the Field Work Proposal entitled Hydrogen Utilization in Internal Combustion Engines (ICE). The goal of the Hydrogen Storage and Delivery System Development Project is to expand the state-of-the-art of hydrogen storage and delivery system design and development. At the foundation of this activity is the development of both analytical and experimental evaluation platforms. These tools provide the basis for an integrated approach for coupling hydrogen storage and delivery technology to the operating characteristics of potential hydrogen energy use applications. Results of the analytical model development portion of this project will be discussed. Analytical models have been developed for internal combustion engine (ICE) hybrid and fuel cell driven vehicles. The dependence of hydride storage system weight and energy use efficiency on engine brake efficiency and exhaust temperature for ICE hybrid vehicle applications is examined. Results show that while storage system weight decreases with increasing engine brake efficiency energy use efficiency remains relatively unchanged. The development, capability, and use of a recently developed fuel cell vehicle storage system model will also be discussed. As an example of model use, power distribution and control for a simulated driving cycle is presented. Model calibration results of fuel cell fluid inlet and exit temperatures at various fuel cell idle speeds, assumed fuel cell heat capacities, and ambient temperatures are presented. The model predicts general increases in temperature with fuel cell power and differences between inlet and exit temperatures, but under predicts absolute temperature values, especially at higher power levels.
Full Text Available Hakki U Ozok,1 Okan Ekim,2 Hakan Saltas,3 Ata T Arikok,4 Orkun Babacan,5 Levent Sagnak,1 Hikmet Topaloglu,1 Hamit Ersoy11Department of Urology, 3Department of Microbiology, 4Department of Pathology, Diskapi Yildirim Beyazit Training and Research Hospital, Ministry of Health, Ankara, Turkey; 2Department of Anatomy, 5Department of Microbiology, Ankara University Faculty of Veterinary Medicine, Ankara, TurkeyPurpose: There is currently an emerging need for developing improved approaches for preventing urinary tract infections (UTIs occurring during diagnostic or interventional procedures of the lower urinary tract. We aimed to establish a rat model to assess the use of transurethral antibiotic administration and to provide evidence that this could be used as a preventive therapy.Methods: Animals received fosfomycin trometamol (FOF either urethrally or orally prior to the procedure. A third group was generated as treatment controls and did not receive any medication. Urethral dilation was conducted to recapitulate an interventional procedure prior to intravesical Escherichia coli administration in all three groups. Finally, sham-operated animals were introduced as a fourth group which did not receive antibiotics or E. coli. Colony counts of urine and tissue cultures for the identification of E. coli and histopathological examinations of the bladder and prostate were conducted.Results: Evaluation of infection intensities in cultures as well as histopathological examination of the bladder and prostate demonstrated a preventative role of transurethral FOF administration. In terms of efficiency, local administration of FOF was similar to oral administration.Conclusions: These results suggest that transurethral antibiotic administration is a promising alternative for preventing UTIs occurring during diagnostic or interventional procedures of the lower urinary tract.Keywords: cystitis, fosfomycin, infection, prostatitis, urinary tract
Advanced and controlled drug delivery systems are important for clinical disease management. In this review the most important new systems which have reached clinical application are highlighted. Microbiologically controlled drug delivery is important for gastrointestinal diseases like ulcerative co
Full Text Available Transport of drugs applied by traditional dosage forms is restricted to the eye, and therapeutic drug concentrations in the target tissues are not maintained for a long duration since the eyes are protected by a unique anatomy and physiology. For the treatment of the anterior segment of the eye, various droppable products to prolong the retention time on the ocular surface have been introduced in the market. On the other hand, direct intravitreal implants, using biodegradable or non-biodegradable polymer technology, have been widely investigated for the treatment of chronic vitreoretinal diseases. There is urgent need to develop ocular drug delivery systems which provide controlled release for the treatment of chronic diseases, and increase patient’s and doctor’s convenience to reduce the dosing frequency and invasive treatment. In this article, progress of ocular drug delivery systems under clinical trials and in late experimental stage is reviewed.
Full Text Available Antibiotics are valuable drugs that fight bacterial infections, but our supply of antibiotics is at risk. Existing antibiotics gradually lose their effectiveness due to bacterial resistance, and few new antibiotics are being developed to replace them. A variety of models have been proposed to promote the conservation of existing antibiotics or incentivize private actors, i.e., drug companies, to develop new ones. Previous models, however, all encourage investment in antibiotic research and development via patent rights, which also create an incentive to oversell antibiotics. Because the inappropriate use of antibiotics accelerates the development of resistance, patent rights put the public health objectives of antibiotic development and conservation in tension with one another. This article proposes an antibiotic-specific patent prize system that uncouples the two policy objectives necessary to achieve a stable antibiotic supply. Although others have proposed patent prize systems to promote drug development generally, the system described here is tailored to address the unique features of antibiotic markets.
Sharma Ritika; Rajput Meenu; Prakash Pawan; Sharma Saurabh
Tablet is the most popular among all dosage forms existing today because of its convenience of self administration, compactness and easy manufacturing; however in many cases immediate onset of action is required than conventional therapy. To overcome these drawbacks, immediate release pharmaceutical dosage form has emerged as alternative oral dosage forms. There are novel types of dosage forms that act very quickly after administration. Drug delivery systems are becoming sophisticated day by ...
Full Text Available Conventional drug delivery systems are often not suitable for new protein based and other Therapeutic compounds produced by modern technology. Therefore an alternative Approach to deliver these drugs can be achieved through the skin in the form of transcutaneous drug delivery system. Modern medicine has responded with the development of methods to deliver drug transcutanously (through the skin for therapeutic use as an alternative to traditional route including oral, intravascular, intramuscular, subcutaneous, and sublingual. Transcutaneous drug delivery has many theoretic and practical advantage and disadvantages, and such issues are often a concern for both clinicians and patients. Transcutaneous patches are flexible pharmaceutical preparations of varying sizes, containing one or more active ingredient, intended to be applied to the unbroken skin in order to deliver the active ingredient to the systemic circulation after passing through the skin barriers. A Transcutaneous patch or skin patch is a medicated adhesive patch that is placed on the skin to deliver a specific dose of medication through the skin and into the bloodstream. Often, this promotes healing to an injured area of the body. In this method, the drug enters the bloodstream directly through skin and it avoid first pass effect. Characterization of Transcutaneous patch are necessary because check it’s quality, size, time of onset & duration, adhesive property, thickness, weight of patch, moisture of content, uniformity & cutaneous toxicological studies. Their requirements for evaluation are HPLC, U.V. spectrophotometer, screw gauge, digital balance, desiccators, thin layer chromatography & K.C. Cell used.
Colone, Marisa; Kaliappan, Subramanian; Calcabrini, Annarica; Tortora, Mariarosaria; Cavalieri, Francesca; Stringaro, Annarita
Recently, nanomedicine has received increasing attention for its ability to improve the efficacy of cancer therapeutics. Nanosized polymer therapeutic agents offer the advantage of prolonged circulation in the blood stream, targeting to specific sites, improved efficacy and reduced side effects. In this way, local, controlled delivery of the drug will be achieved with the advantage of a high concentration of drug release at the target site while keeping the systemic concentration of the drug low, thus reducing side effects due to bioaccumulation. Various drug delivery systems such as nanoparticles, liposomes, microparticles and implants have been demonstrated to significantly enhance the preventive/therapeutic efficacy of many drugs by increasing their bioavailability and targetability. As these carriers significantly increase the therapeutic effect of drugs, their administration would become less cost effective in the near future. The purpose of our research work is to develop a delivery system for breast cancer cells using a microvector of drugs. These results highlight the potential uses of these responsive platforms suited for biomedical and pharmaceutical applications. At the request of all authors of the paper an updated version was published on 12 July 2016. The manuscript was prepared and submitted without Dr. Francesca Cavalieri's contribution and her name was added without her consent. Her name has been removed in the updated and re-published article.
Shyamal Kumar Kundu
Full Text Available Advancement in the gene delivery system have resulted in clinical successes in gene therapy for patients with several genetic diseases, such as immunodeficiency diseases, X-linked adrenoleukodystrophy (X-ALD blindness, thalassemia, and many more. Among various delivery systems, liposomal mediated gene delivery route is offering great promises for gene therapy. This review is an attempt to depict a portrait about the polymer based liposomal gene delivery systems and their future applications. Herein, we have discussed in detail the characteristics of liposome, importance of polymer for liposome formulation, gene delivery, and future direction of liposome based gene delivery as a whole.
Alimoradi, Houman; Matikonda, Siddharth S; Gamble, Allan B; Giles, Gregory I; Greish, Khaled
Hypoxia is a common characteristic of solid tumors. It is mainly determined by low levels of oxygen resulting from imperfect vascular networks supplying most tumors. In an attempt to improve the present chemotherapeutic treatment and reduce associated side effects, several prodrug strategies have been introduced to achieve hypoxia-specific delivery of cytotoxic anticancer agents. With the advances in nanotechnology, novel delivery systems activated by the consequent outcomes of hypoxia have been developed. However, developing hypoxia responsive drug delivery systems (which only depend on low oxygen levels) is currently naïve. This review discusses four main hypoxia responsive delivery systems: polymeric based drug delivery systems, oxygen delivery systems combined with radiotherapy and chemotherapy, anaerobic bacteria which are used for delivery of genes to express anticancer proteins such as tumor necrosis alpha (TNF-α) and hypoxia-inducible transcription factors 1 alpha (HIF1α) responsive gene delivery systems.
Alimoradi, Houman; Matikonda, Siddharth S; Gamble, Allan B; Giles, Gregory I; Greish, Khaled
Hypoxia is a common characteristic of solid tumors. It is mainly determined by low levels of oxygen resulting from imperfect vascular networks supplying most tumors. In an attempt to improve the present chemotherapeutic treatment and reduce associated side effects, several prodrug strategies have been introduced to achieve hypoxia-specific delivery of cytotoxic anticancer agents. With the advances in nanotechnology, novel delivery systems activated by the consequent outcomes of hypoxia have been developed. However, developing hypoxia responsive drug delivery systems (which only depend on low oxygen levels) is currently naïve. This review discusses four main hypoxia responsive delivery systems: polymeric based drug delivery systems, oxygen delivery systems combined with radiotherapy and chemotherapy, anaerobic bacteria which are used for delivery of genes to express anticancer proteins such as tumor necrosis alpha (TNF-α) and hypoxia-inducible transcription factors 1 alpha (HIF1α) responsive gene delivery systems. PMID:26898739
Full Text Available Transdermal drug delivery system (TDDS is one of the systems lying under the category of controlled drug delivery, in which the aim is to deliver the drug through the skin in a predetermined and controlled rate. It has various advantages, like prolonged therapeutic effect, reduced side-effects, improved bioavailability, better patient compliance and easy termination of drug therapy. The stratum corneum is considered as the rate limiting barrier in transdermal permeation of most molecules. There are three main routes of drug penetration, which include the appendageal, transcellular and intercellular routes. Skin age, condition, physicochemical factors and environmental factors are some factors that are to be considered while delivering drug through this route. Basic components of TDDS include polymer matrix, membrane, drug, penetration enhancers, pressure-sensitive adhesives, backing laminates, release liner, etc. Transdermal patches can be divided into various systems like reservoir system, matrix system and micro-reservoir system, which are used to incorporate the active ingredients into the circulatory system via the skin. After preparation of transdermal patches, consistent methodology are adopted to test the adhesion properties, physicochemical properties, in vitro drug release studies, in vitro skin permeation studies, skin irritation studies and stability studies. According to the duration of therapy, various drugs are commercially available in the form of transdermal patches.
Abadi, Danielle; Zderic, Vesna
A novel ultrasound-mediated drug delivery system has been developed for treatment of a nail fungal disorder (onychomycosis) by improving delivery to the nail bed using ultrasound to increase the permeability of the nail. The slip-in device consists of ultrasound transducers and drug delivery compartments above each toenail. The device is connected to a computer, where a software interface allows users to select their preferred course of treatment. In in vitro testing, canine nails were exposed to 3 energy levels (acoustic power of 1.2 W and exposure durations of 30, 60, and 120 seconds). A stereo -microscope was used to determine how much of a drug-mimicking compound was delivered through the nail layers by measuring brightness on the cross section of each nail tested at each condition, where brightness level decreases coincide with increases in permeability. Each of the 3 energy levels tested showed statistical significance when compared to the control (P permeability factor of 1.3 after 30 seconds of exposure, 1.3 after 60 seconds, and 1.5 after 120 seconds, where a permeability factor of 1 shows no increase in permeability. Current treatments for onychomycosis include systemic, topical, and surgical. Even when used all together, these treatments typically take a long time to result in nail healing, thus making this ultrasound-mediated device a promising alternative. PMID:22124008
Full Text Available Oral route still remains the favorite route of drug administration in many diseases and till today it is the first wayinvestigated in the development of new dosage forms. Approximately 40 per cent of new drug candidates have poor water solubility and the oral delivery ofsuch drugs is frequently associated with implications of low bioavailability, high intra and inter-subjectvariability, and lack of dose proportionality. Bioavailability problem of lipophillic drugs can be solved byformation of Self Emulsifying Drug Delivery System (SEDDS. SEDDS are isotropicmixtures of oil, surfactant, co-surfactant and drug with a unique ability to form fine oil in water microemulsion upon mild agitation following dilution with aqueous phase. The principal characteristic of thesesystems is their ability to form fine oil-in-water (o/w emulsions or micro-emulsions upon mild agitation followingdilution by an aqueous phase. For lipophilic drugs, which have dissolution rate-limited absorption, SEDDS may be apromising strategy to improve the rate and extent of oral absorption.This review article explains how self-emulsifying drug delivery systems can increase the solubility and bioavailability ofpoorly soluble drug.
Abadi, Danielle; Zderic, Vesna
A novel ultrasound-mediated drug delivery system has been developed for treatment of a nail fungal disorder (onychomycosis) by improving delivery to the nail bed using ultrasound to increase the permeability of the nail. The slip-in device consists of ultrasound transducers and drug delivery compartments above each toenail. The device is connected to a computer, where a software interface allows users to select their preferred course of treatment. In in vitro testing, canine nails were exposed to 3 energy levels (acoustic power of 1.2 W and exposure durations of 30, 60, and 120 seconds). A stereo -microscope was used to determine how much of a drug-mimicking compound was delivered through the nail layers by measuring brightness on the cross section of each nail tested at each condition, where brightness level decreases coincide with increases in permeability. Each of the 3 energy levels tested showed statistical significance when compared to the control (P permeability factor of 1.3 after 30 seconds of exposure, 1.3 after 60 seconds, and 1.5 after 120 seconds, where a permeability factor of 1 shows no increase in permeability. Current treatments for onychomycosis include systemic, topical, and surgical. Even when used all together, these treatments typically take a long time to result in nail healing, thus making this ultrasound-mediated device a promising alternative.
Full Text Available Nanotechnology has finally and firmly entered the realm of drug delivery. Performances of intelligent drug delivery systems are continuously improved with the purpose to maximize therapeutic activity and to minimize undesirable side-effects. This review describes the advanced drug delivery systems based on micelles, polymeric nanoparticles, and dendrimers. Polymeric carbon nanotubes and many others demonstrate a broad variety of useful properties. This review emphasizes the main requirements for developing new nanotech-nology-based drug delivery systems.
Malakar Jadupati; Das Tanmay; Ghatak Souvik
In this review, the various new and well established technologies relevant to the controlled and targeted drug delivery systems have been precisely discussed. A perfectly designed controlled drug delivery system can be of huge advantage towards solving problems concerning to the targeting of drug to a specific organ or tissue and controlling the rate of drug delivery at the target site. Novel drug delivery systems have various advantages over other conventional drug therapy. In which microenc...
Jepsen, Karin; Jepsen, Søren
This review gives an update of the current scientific evidence on the efficacy of the adjunctive use of systemic and local antibiotics/antimicrobials in the treatment of periodontitis. In particular, it addresses whether their use can improve the results of nonsurgical mechanical therapy in mild-to-moderate forms of the disease. Large numbers of randomized clinical trials and systematic reviews with meta-analyses have clearly established that adjunctive systemic antibiotics, combined with mechanical debridement, offer clinical improvements additional to those obtained with scaling and root planing alone. These effects are more pronounced in aggressive periodontitis and in initially deep pockets, whereas more limited additional improvements, of 0.3 mm for additional pocket reduction and 0.2 mm for additional clinical attachment gain, have been documented for moderately deep sites (4-6 mm) in patients with chronic periodontitis. The marginal clinical benefit in patients with moderate disease has to be balanced against possible side effects. Notably, it has to be realized that an increasing number of warnings have been articulated against the unrestricted use of antibiotics in treating periodontal diseases because of the emerging global public health issue of bacterial resistance. The effects of the adjunctive local administration of antimicrobials have also been very well documented in several systematic reviews. Overall, in persistent or recurrent localized deep sites, the application of antimicrobials by sustained-delivery devices may offer a benefit of an additional 0.4 mm in pocket depth reduction and 0.3 mm in clinical attachment level gain. In conclusion, the slight additional benefits of adjunctive antimicrobials, which were shown for moderate forms of periodontitis, have to be balanced against their side effects and therefore their prescription should be limited as much as possible. PMID:27045432
Full Text Available The human skin is a readily accessible surface for drug delivery. Skin of an average adult body covers a surface of approximately 2 m2 and receives about one-third of the blood circulating through the body. Over the past decades, developing controlled drug delivery has become increasingly important in the pharmaceutical industry. The human skin surface is known to contain, on an average, 10- 70 hair follicles and 200-250 sweat ducts on every square centimeters of the skin area. It is one of the most readily accessible organs of the human body. There is considerable interest in the skin as a site of drug application both for local and systemic effect. However, the skin, in particular the stratum corneum, poses a formidable barrier to drug penetration thereby limiting topical and transdermal bioavailability. Skin penetration enhancement techniques have been developed to improve bioavailability and increase the range of drugs for which topical and transdermal delivery is a viable option. During the past decade, the number of drugs formulated in the patches has hardly increased, and there has been little change in the composition of the patch systems. Modifications have been mostly limited to refinements of the materials used. The present review article explores the overall study on transdermal drug delivery system (TDDS which leads to novel drug delivery system (NDDS.
Vadlamudi, Harini C; Narendran, Hyndavi; Nagaswaram, Tejeswari; Yaga, Gowri; Thanniru, Jyotsna; Yalavarthi, Prasanna R
Since the discovery of microemulsions by Jack H Schulman, there has been huge progress made in applying microemulsion systems in plethora of research and industrial process. Microemulsions are optically isotropic systems consisting of water, oil and amphiphile. These systems are beneficial due to their thermodynamic stability, optical clarity, ease of preparation, higher diffusion and absorption rates. Moreover, it has been reported that the ingredients of microemulsion can effectively overcome the diffusion barrier and penetrate through the stratum corneum of the skin. Hence it becomes promising for both transdermal and dermal drug delivery. However, low viscosity of microemulsion restrains its applicability in pharmaceutical industry. To overcome the above drawback, the low viscous microemulsions were added to viscous gel bases to potentiate its applications as topical drug delivery systems so that various drug related toxic effects and erratic drug absorption can be avoided. The present review deals with the microemulsions, various techniques involved in the development of organic nanoparticles. The review emphasized on microemulsion based systems such as hydrogels and organogels. The physicochemical characteristics, mechanical properties, rheological and stability principles involved in microemulsion based viscous gels were also explored. PMID:25466399
... 42 Public Health 4 2010-10-01 2010-10-01 false Delivery and utilization control systems. 457.490... State Plan Requirements: Coverage and Benefits § 457.490 Delivery and utilization control systems. A... targeted low-income children, including a description of the proposed methods of delivery and...
Yang, Gaomai; Lv, Fengting; Wang, Bing; Liu, Libing; Yang, Qiong; Wang, Shu
Multifunctional nanomaterials with simultaneous therapeutic and imaging functions explore new strategies for the treatment of various diseases. Conjugated polymers (CPs) are considered as novel candidates to serve as multifunctional delivery systems due to their high fluorescence quantum yield, good photostability, and low cytotoxicity. Highly sensitive sensing and imaging properties of CPs are well reviewed, while the applications of CPs as delivery systems are rarely covered. This feature article mainly focuses on CP-based multifunctional non-viral delivery systems for drug, protein, gene, and cell delivery. Promising directions for the further development of CP-based delivery systems are also discussed.
Medina, Luis Alberto
Liposome drug formulations are defined as pharmaceutical products containing active drug substances encapsulated within the lipid bilayer or in the interior aqueous space of the liposomes. The main importance of this drug delivery system is based on its drastic reduction in systemic dose and concomitant systemic toxicity that in comparison with the free drug, results in an improvement of patient compliance and in a more effective treatment. There are several therapeutic drugs that are potential candidates to be encapsulated into liposomes; particular interest has been focused in therapeutic and antineoplastic drugs, which are characterized for its low therapeutic index and high systemic toxicity. The use of liposomes as drug carriers has been extensively justified and the importance of the development of different formulations or techniques to encapsulate therapeutic drugs has an enormous value in benefit of patients affected by neoplastic diseases.
Bindu M Boddupalli
Full Text Available Mucoadhesive drug delivery systems interact with the mucus layer covering the mucosal epithelial surface, and mucin molecules and increase the residence time of the dosage form at the site of absorption. The drugs which have local action or those which have maximum absorption in gastrointestinal tract (GIT require increased duration of stay in GIT. Thus, mucoadhesive dosage forms are advantageous in increasing the drug plasma concentrations and also therapeutic activity. In this regard, this review covers the areas of mechanisms and theories of mucoadhesion, factors influencing the mucoadhesive devices and also various mucoadhesive dosage forms.
Full Text Available Tablet is the most popular among all dosage forms existing today because of its convenience of self administration, compactness and easy manufacturing; however in many cases immediate onset of action is required than conventional therapy. To overcome these drawbacks, immediate release pharmaceutical dosage form has emerged as alternative oral dosage forms. There are novel types of dosage forms that act very quickly after administration. Drug delivery systems are becoming sophisticated day by day as pharmaceutical scientists has acquired a better understanding of the physicochemical and biochemical parameters of drugs and excipients. Over the past three decades, fast disintegrating tablets (FDTs have gained considerable attention and is one of the most widely employed commercial product which is preferred alternative to conventional tablets and capsules especially for the pediatric and geriatric patients and for the patients who are bedridden, those having hand tremors, motion sickness, disphagia and who may not have access to water during traveling or who are uncooperative, on reduced liquid intake plan and also preferred in sudden episodes of allergic attack. Fast-dissolving drug delivery systems may offer a solution for these problems.
Full Text Available Objective. To prepare biocompatible ciprofloxacin-loaded carboxymethyl chitosan nanoparticles (CCC NPs and evaluate their cell specificity as well as antibacterial activity against Escherichia coli in vitro. Methods. CCC NPs were prepared by ionic cross-linking method and optimized by using Box-Behnken response surface method (BBRSM. Zeta potential, drug encapsulation, and release of the obtained nanoparticles in vitro were thoroughly investigated. Minimum inhibitory concentration (MIC and killing profiles of free or ciprofloxacin-loaded nanoparticles against Escherichia coli were documented. The cytotoicity of blank nanoparticles and cellular uptake of CCC NPs were also investigated. Results. The obtained particles were monodisperse nanospheres with an average hydrated diameter of 151 ± 5.67 nm and surface of charge −22.9 ± 2.21 mV. The MICs of free ciprofloxacin and CCC NPs were 0.16 and 0.08 μg/mL, respectively. Blank nanoparticles showed no obvious cell inhibition within 24 h, and noticeable phagocytosis effect was observed in the presence of CCC NPs. Conclusion. This study shows that CCC NPs have stronger antibacterial activity against Escherichia coli than the free ciprofloxacin because they can easily be uptaken by cells. The obtained CCC NPs have promising prospect in drug delivery field.
Johnson, Noah R.; Wang, Yadong
Coacervates represent an exciting new class of drug delivery vehicles, developed in the past decade as carriers of small molecule drugs and proteins. This review summarizes several well-described coacervate systems, including Elastin-like peptides for delivery of anti-cancer therapeutics,Heparin-based coacervates with synthetic polycations for controlled growth factor delivery,Carboxymethyl chitosan aggregates for oral drug delivery,Mussel adhesive protein and hyaluronic acid coacervates.
Full Text Available Nanoemulsion has been identified as a promising delivery system for various drugs including biopharmaceuticals. Nanoemulsion is a heterogeneous system composed of one immiscible liquid dispersed as droplets within another liquid. The droplets size of nano emulsion is between 20 to 500 nm. Diameter and surface properties of droplets of nanoemulsion plays an important role in the biological behavior of the formulation. Small droplet sizes lead to transparent emulsions so that product appearance is not altered by the addition of an oil phase. In this paper various aspects of nanoemulsion have been discussed including advantages, disadvantages and methods of preparation. Furthermore new approaches of stability of formulation, effect of types and concentration of surfactant, process variables and method are also discussed to improve the stability of nanoemulsion formulation
Full Text Available Novel technologies have been developed recently for drug delivery systems. The use of herbal formulations for novel drug delivery systems is more advantageous and has more benefits compared to others. The use of liposome, ethosome, phytosomes, emulsion, microsphere, solid lipid nanoparticles of herbal formulation has enhanced the therapeutic effects of plant extracts. With the use of all these, targeted delivery of the formulation is achieved, due to which the formulation demonstrates effect on the site, and the bioavailability of the formulation is also increased. With these novel drug delivery systems, the actives and extracts which are used in herbal formulations demonstrate enhancement in stability, sustained release of formulation, protection from toxicity and improved therapeutic efficacy. The main purpose of developing alternative drug delivery technologies is to increase efficiency of drug delivery and safety in the process of drug delivery and provide more convenience for the patient. The present paper includes information about novel formulations of herbal formulations.
Full Text Available Today about 70% of drugs are taken orally and are found not to be as effective as desired. To improvesuch characters transdermal drug delivery system was emerged. Transdermal drug delivery system(TDDS provides a means to sustain drug release as well as reduce the intensity of action and thusreduce the side effects associated with its oral therapy and differs from traditional topical drug delivery.Transdermal Drug Delivery System is the system in which the delivery of the active ingredients of thedrug occurs by means of skin. Several important advantages of transdermal drug delivery are limitationof hepatic first pass metabolism, enhancement of therapeutic efficiency and maintenance of steadyplasma level of the drug. Various types of transdermal patches are used to incorporate the activeingredients into the circulatory system via skin. This review article covers a brief outline of theprinciples of transdermal permeation, various components of transdermal patch, approaches oftransdermal patch, evaluation of transdermal system, its application with its limitation.
DASH ALOK KUMAR; MISHRA JHANSEE
Several controlled oral drug delivery systems with prolonged gastric residence time have been reported recently. Gastro retentive drug delivery system is an approach to prolong gastric residence time, thereby targeting site-specific drug release in upper gastro intestinal tract improving the oral sustained delivery of drug that have an absorption window in a particular region of the gastrointestinal tract. These systems help in continuously releasing the drug before it reaches the absorption ...
Singh Amit Kumar; Dubey Vivek; Arora Vandana
Floating drug delivery system is the form of gastro-retentive drug delivery system that controls the kinetic release rate of a drug to a specific site for its pharmacological action. These are achieved by use of various polymeric substance including natural polymers such as Guar Gum, Xanthan Gum, Gellan Gum etc. This delivery system prolongs the retention time of the drug in the stomach as compared to conventional dosage forms. The present article highlights the use of polymers for the formul...
L. K. Omray
Gastro retentive drug delivery system of diltiazem hydrochloride was designed and evaluated for its effectiveness for the management of mild to moderate hypertension. Gastro retentive drug delivery system were prepared using polyvinyl alcohol and sodium carboxy methyl cellulose as the polymers and sodium bicarbonate as a gas generating agent for the reduction of floating lag time. Gastro retentive drug delivery system tablets were prepared by wet granulation method by compression in tablet co...
D. Nagasamy Venkatesh
Full Text Available Proniosomes are solid colloidal particles which may be hydrated immediately before use to yield aqueous niosomes dispersions similar to those produced by more cumbersome conventional methods. The proniosomes minimize the problems associated with niosomes in terms of its physical stability such as aggregation, fusion and leaking. They also offer an additional convenience in transportation, distribution, storage, and dosing. The proniosomes derived niosomes are better than conventional niosomes in terms of their morphology, particle size, particle size distribution, and drug release. A slurry method was commonly used to produce proniosomes using maltodextrin as carrier. The time required to produce proniosomes by this simple method is independent of the ratio of surfactant solution to carrier material and appears to be a scalable process. The encapsulation efficiency of proniosomes is depends upon the amount of maltodextrin used in the process. The present review describes the method of preparation, characterization, applications of proniosomes as a potential drug delivery system.
Singh Amit Kumar
Full Text Available Floating drug delivery system is the form of gastro-retentive drug delivery system that controls the kinetic release rate of a drug to a specific site for its pharmacological action. These are achieved by use of various polymeric substance including natural polymers such as Guar Gum, Xanthan Gum, Gellan Gum etc. This delivery system prolongs the retention time of the drug in the stomach as compared to conventional dosage forms. The present article highlights the use of polymers for the formulation of the floating drug delivery system especially with natural polymers.
Dextran-based microspheres as controlled delivery systems for proteins Dextran based microspheres are investigated as controlled delivery system for proteins. Microspheres were prepared by polymerization of dex-HEMA in an aqueous two-phase system of dex-HEMA and PEG. Protein loaded microspheres are
Gosenca, Mirjam; GAŠPERLIN, MIRJANA
This study examined the suitability of various colloidal systems for ascorbyl palmitate (AP) skin delivery. First, a pseudoternary phase diagram for Tween 80/lecithin/butanol, isopropyl myristate (IPM), and water was constructed and regions of lipophilic (w/o) or hydrophilic (o/w) microemulsions (MEs), and emulsions (EMs) were identified. Afterwards, various phase transition systems on the selected dilution line, as well as liquid crystal (LC) as a delivery system on the same dilution line (b...
Ritesh Kumar1*, Amrish Chandra2, Pawan Kumar Gautam3
Full Text Available The colon is a site where both local and systemic delivery of drugs can take place. Local delivery allows topicaltreatment of inflammatory bowel disease. However, treatment can be made effective if the drugs can be targeteddirectly into the colon, thereby reducing the systemic side effects. This review mainly describes the primaryapproaches for CDDS (Colon Specific Drug Delivery namely prodrugs, pH and time dependent systems, andmicrobially triggered systems, which achieved limited success and had limitations as compared with newer CDDSnamely pressure controlled colonic delivery capsules. Oral administration of different dosage forms is the mostcommonly used method due to flexibility in design of dosage form and high patient acceptance, but thegastrointestinal tract presents several formidable barriers to drug delivery. In oral colon-specific drug deliverysystem, colon has a large amount of lymphoma tissue (facilitates direct absorption in to the blood, negligible brushboarder membrane activity, and much less pancreatic enzymatic activity as compared with the small intestine.Colon-specific drug delivery has gained increased importance not just for the delivery of the drugs for treatment oflocal diseases associated with the colon but also for its potential for the delivery of proteins and therapeutic peptides.Different approaches are designed based on prodrug formulation, pH-sensitivity, time-dependency (lag time,microbial degradation and osmotic pressure etc to formulate the different dosage forms like tablets, capsules,multiparticulates, microspheres, liposomes for colon targeting. The delivery of drugs to the colon has a number oftherapeutic implications in the field of drug delivery. In the recent times, the colon specific delivery systems are alsogaining importance not only for local drug delivery of drugs but also for the systemic delivery of protein and peptidedrugs. This review updated the research on different approaches formulation and
DASH ALOK KUMAR
Full Text Available Several controlled oral drug delivery systems with prolonged gastric residence time have been reported recently. Gastro retentive drug delivery system is an approach to prolong gastric residence time, thereby targeting site-specific drug release in upper gastro intestinal tract improving the oral sustained delivery of drug that have an absorption window in a particular region of the gastrointestinal tract. These systems help in continuously releasing the drug before it reaches the absorption window, thus ensuring optimal bioavailability. Various approaches for gastric retention are Floating system, Swelling and expanding system, Bioadhesive systems, Modified-shape systems, High density systems etc.
Full Text Available In this review, the various new and well established technologies relevant to the controlled and targeted drug delivery systems have been precisely discussed. A perfectly designed controlled drug delivery system can be of huge advantage towards solving problems concerning to the targeting of drug to a specific organ or tissue and controlling the rate of drug delivery at the target site. Novel drug delivery systems have various advantages over other conventional drug therapy. In which microencapsulation is one approach for achieving the novel drug delivery dosage forms such as sustained release and controlled release, though the development of oral controlled release systems has been a challenge to formulation scientist due to their inability to restrain and focus the system at targeted areas of gastrointestinal tract. Microparticulate drug delivery systems are an interesting and promising option when developing an oral controlled release system. Our objective is to take a closer look at microparticles as drug delivery devices for increasing efficiency of drug delivery, improving the release profile and drug targeting. In order to elucidate the application of microcapsules in drug delivery, some fundamental aspects are briefly reviewed.
V Kusum Devi
Full Text Available Novel drug delivery system is a novel approach to drug delivery that addresses the limitations of the traditional drug delivery systems. Our country has a vast knowledge base of Ayurveda whose potential is only being realized in the recent years. However, the drug delivery system used for administering the herbal medicine to the patient is traditional and out-of-date, resulting in reduced efficacy of the drug. If the novel drug delivery technology is applied in herbal medicine, it may help in increasing the efficacy and reducing the side effects of various herbal compounds and herbs. This is the basic idea behind incorporating novel method of drug delivery in herbal medicines. Thus it is important to integrate novel drug delivery system and Indian Ayurvedic medicines to combat more serious diseases. For a long time herbal medicines were not considered for development as novel formulations owing to lack of scientific justification and processing difficulties, such as standardization, extraction and identification of individual drug components in complex polyherbal systems. However, modern phytopharmaceutical research can solve the scientific needs (such as determination of pharmacokinetics, mechanism of action, site of action, accurate dose required etc. of herbal medicines to be incorporated in novel drug delivery system, such as nanoparticles, microemulsions, matrix systems, solid dispersions, liposomes, solid lipid nanoparticles and so on. This article summarizes various drug delivery technologies, which can be used for herbal actives together with some examples.
Batista, Jorge G.S.; Varca, Gustavo H.C.; Ferraz, Caroline C.; Garrido, Gabriela P.; Diniz, Bruna M.; Carvalho, Vinicius S.; Lugao, Ademar B., E-mail: firstname.lastname@example.org [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)
Hydrogels are formed by polymers capable of absorbing large quantities of water. They consist of one or more three-dimensionally structured polymer networks formed by macromolecular chains linked by covalent bonds-crosslinks - and physical interactions. The application of hydrogels, has been widely studied. Biodegradable synthetic or natural polymers such as chitosan, starch and poly-lactic-co-glycolic acid, have properties that allow the development of biodegradable systems for drug and nutraceutics delivery. This study aimed to develop polymeric hydrogels based on polyvinyl alcohol, polyacrylamide and polyvinylpyrrolidone using ionizing radiation in order to develop hydrogels for improved loading and release of compounds. Polymer solutions were solubilized in water and poured into thermoformed packages. After sealing, the material was subjected to γ-irradiation at 25kGy. The samples were assayed by means of mechanical properties, gel fraction and swelling degree. Nanostructure characterization was performed using Flory's equation to determine crosslinking density. The systems developed showed swelling degree and adequate mechanical resistance. The nanostructure evaluation showed different results for each system demonstrating the need of choosing the polymer based on the specific properties of each material. (author)
Sunena Sethi, SL Harikumar* and Nirmala
Full Text Available The colon is the terminal part of the GIT which has gained in recent years as a potential site for delivery of various novel therapeutic drugs, i.e. peptides. However, colon is rich in microflora which can be used to target the drug release in the colon. Colon is a site where both local and systemic drug delivery can take place. Local delivery allows the topical treatment of inflammatory bowel disease. If drug can be targeted directly into the colon, treatment can become more effective and side effects can be minimized. These systemic side effects can be minimized by primary approaches for CDDS (Colon specific drug delivery namely prodrugs, pH and time dependent systems and microbially triggered system which gained limited success and have limitations as compared with recently new CDDS namely pressure controlled colon delivery capsules (PCDCS, CODESTM (Novel colon targeted delivery system osmotic controlled drug delivery system, Pulsincap system, time clock system, chronotropic system. This review is to understand the pharmaceutical approaches to colon targeted drug delivery systems for better therapeutic action without compromising on drug degradation (or its low bioavailability.
Bjerg, Lise Nørkjær
Specific delivery of drugs to diseased sites in the body is a major topic in the development of drug delivery system today. Especially, the field of cancer treatment needs improved drug delivery systems as the strong dose-limiting side effects of chemotherapy today often present a barrier....... The results were encouraging and proved the large potential of radiolabeled liposomes as candidates for revealing the biodistribution of drug delivery systems. Chapter four deals with one of the large dilemmas, when using liposomes as drug delivery agents. The presence of a shielding polymer layer...... for an effective cure. Liposomes have attracted much attention since they were first proposed as potential drug carrier agents in the 1970s. Chapter one gives an introduction to the strategies used in liposomal drug delivery today. The important issues as enhanced specific uptake in diseased tissue and effective...
Full Text Available Over the past few decades, advances in the in situ gel technologies have spurred development in manymedical and biomedical applications including controlled drug delivery. Many novel in situ gel baseddelivery matrices have been designed and fabricated to fulfill the ever increasing needs of thepharmaceutical and medical fields. In situ gelling systems are liquid at room temperature but undergogelation when in contact with body fluids or change in pH. In situ gel forming drug delivery is a type ofmucoadhesive drug delivery system. The formation of gel depends on factors like temperaturemodulation, pH change, presence of ions and ultraviolet irradiation from which the drug gets released ina sustained and controlled manner. Nasal delivery is a promising drug delivery option where commondrug administrations such as intravenous, intramuscular or oral are inapplicable. Recently, it has beenshown that many drugs have better bioavailability by nasal route than the oral route. This has beenattributed to rich vasculature and a highly permeable structure of the nasal mucosa coupled withavoidance of hepatic first-pass elimination, gut wall metabolism and/or destruction in thegastrointestinal tract. The physiology of the nose presents obstacles but offers a promising route for noninvasivesystemic delivery of numerous therapies and debatably drug delivery route to the brain. Thusthis review focuses on nasal drug delivery, various aspects of nasal anatomy and physiology, nasal drugabsorption mechanisms, various nasal drug delivery systems and their applications in drug delivery.
G T Kulkarni
Full Text Available
Nanoemulsion has been identified as a promising delivery system for various drugs including biopharmaceuticals. Nanoemulsion is a heterogeneous system composed of one immiscible liquid dispersed as droplets within another liquid. The droplets size of nano emulsion is between 20 to 500 nm. Diameter and surface properties of droplets of nanoemulsion plays an important role in the biological behavior of the formulation. Small droplet sizes lead to transparent emulsions so that product appearance is not altered by the addition of an oil phase. In this paper various aspects of nanoemulsion have been discussed including advantages, disadvantages and methods of preparation. Furthermore new approaches of stability of formulation, effect of types and concentration of surfactant, process variables and method are also discussed to improve the stability of nanoemulsion formulation
Izhar Ahmed Syed
Full Text Available The “Liquisolid” technique is a novel and capable addition towards such an aims for solubility enhancement and dissolution improvement, thereby it increases the bioavailability. It contains liquid medications in powdered form. This technique is an efficient method for formulating water insoluble and water soluble drugs. This technique is based upon the admixture of drug loaded solutions with appropriate carrier and coating materials. The use of non-volatile solvent causes improved wettability and ensures molecular dispersion of drug in the formulation and leads to enhance solubility. By using hydrophobic carriers (non-volatile solvents one can modify release (sustained release of drugs by this technique. Liquisolid system is characterized by flow behavior, wettability, powder bed hydrophilicity, saturation solubility, drug content, differential scanning calorimetry, Fourier transform infra red spectroscopy, powder X-ray diffraction, scanning electron microscopy, in-vitro release and in-vivo evaluation. By using this technique, solubility and dissolution rate can be improved, sustained drug delivery systems be developed for the water soluble drugs.
in vivo, toxicity and non-specific stimulation of the immune system. To optimally design and tailor the lipidic systems for siRNA delivery, better insight is needed into the mechanisms of cell delivery. More specifically, further clarification is need regarding the nature of cell surface interactions...
Meng, Ellis; Hoang, Tuan
Implantable drug-delivery systems provide new means for achieving therapeutic drug concentrations over entire treatment durations in order to optimize drug action. This article focuses on new drug administration modalities achieved using implantable drug-delivery systems that are enabled by micro- and nano-fabrication technologies, and microfluidics. Recent advances in drug administration technologies are discussed and remaining challenges are highlighted.
American Psychologist, 2013
Psychologists practice in an increasingly diverse range of health care delivery systems. The following guidelines are intended to assist psychologists, other health care providers, administrators in health care delivery systems, and the public to conceptualize the roles and responsibilities of psychologists in these diverse contexts. These…
Singh, Deependra; Pradhan, Madhulika; Nag, Mukesh; Singh, Manju Rawat
The transdermal route of drug delivery has gained immense interest for pharmaceutical researchers. The major hurdle for diffusion of drugs and bioactives through transdermal route is the stratum corneum, the outermost layer of the skin. Currently, various approaches such as physical approach, chemical approach, and delivery carriers have been used to augment the transdermal delivery of bioactives. This review provides a brief overview of mechanism of drug transport across skin, different lipid vesicular systems, with special emphasis on lipid vesicular systems including transfersomes, liposomes, niosomes, ethosomes, virosomes, and pharmacosomes and their application for the delivery of different bioactives. PMID:24564350
Controlled drug delivery technology has progressed over the last six decades. This progression began in 1952 with the introduction of the first sustained release formulation. The 1st generation of drug delivery (1950-1980) focused on developing oral and transdermal sustained release systems and establishing controlled drug release mechanisms. The 2nd generation (1980-2010) was dedicated to the development of zero-order release systems, self-regulated drug delivery systems, long-term depot formulations, and nanotechnology-based delivery systems. The latter part of the 2nd generation was largely focused on studying nanoparticle formulations. The Journal of Controlled Release (JCR) has played a pivotal role in the 2nd generation of drug delivery technologies, and it will continue playing a leading role in the next generation. The best path towards a productive 3rd generation of drug delivery technology requires an honest, open dialog without any preconceived ideas of the past. The drug delivery field needs to take a bold approach to designing future drug delivery formulations primarily based on today's necessities, to produce the necessary innovations. The JCR provides a forum for sharing the new ideas that will shape the 3rd generation of drug delivery technology.
Shaji Jessy; Shinde Amol B
Pulsatile drug delivery aims to release drugs in a planned pattern i.e. at appropriate time and/or at a suitable site of action. Pharmaceutical invention and research are increasingly focusing on delivery systems which enhance desirable therapeutic objectives while minimising side effects. However, in recent pharmaceutical applications involving pulsatile delivery, multiparticulate dosage forms are gaining much favour over single-unit dosage forms because of their potential benefits like pred...
Dvorak, Rudolf; Süli, Áron; Sándor, Zsolt; Galiazzo, Mattia; Pilat-Lohinger, Elke
As part of the national scientific network 'Pathways to Habitable Worlds' the delivery of water onto terrestrial planets is a key question since water is essential for the development of life as we know it. After summarizing the state of the art we show some first results of the transport of water in the early Solar System for scattered main belt objects. Hereby we investigate the questions whether planetesimals and planetesimal fragments which have gained considerable inclination due to the strong dynamical interactions in the main belt region around 2 AU can be efficient water transporting vessels. The Hungaria asteroid group is the best example that such scenarios are realistic. Assuming that the gas giants and the terrestrial planets are already formed, we monitor the collisions of scattered small bodies containing water (in the order of a few percent) with the terrestrial planets. Thus we are able to give a first estimate concerning the respective contribution of such bodies to the actual water content i...
Matias J. Cardoso
Full Text Available Oceans are a vast source of natural substances. In them, we find various compounds with wide biotechnological and biomedical applicabilities. The exploitation of the sea as a renewable source of biocompounds can have a positive impact on the development of new systems and devices for biomedical applications. Marine polysaccharides are among the most abundant materials in the seas, which contributes to a decrease of the extraction costs, besides their solubility behavior in aqueous solvents and extraction media, and their interaction with other biocompounds. Polysaccharides such as alginate, carrageenan and fucoidan can be extracted from algae, whereas chitosan and hyaluronan can be obtained from animal sources. Most marine polysaccharides have important biological properties such as biocompatibility, biodegradability, and anti-inflammatory activity, as well as adhesive and antimicrobial actions. Moreover, they can be modified in order to allow processing them into various shapes and sizes and may exhibit response dependence to external stimuli, such as pH and temperature. Due to these properties, these biomaterials have been studied as raw material for the construction of carrier devices for drugs, including particles, capsules and hydrogels. The devices are designed to achieve a controlled release of therapeutic agents in an attempt to fight against serious diseases, and to be used in advanced therapies, such as gene delivery or regenerative medicine.
Mantripragada, Venkata P; Jayasuriya, Ambalangodage C
The main aims of this manuscript are to: i) determine the effect of commonly used antibiotics to treat osteoarticular infections on osteoblast viability, ii) study the dual release of the growth factor (BMP-7) and antibiotics (vancomycin and cefazolin) from chitosan microparticles iii) demonstrate the bioactivity of the antibiotics released in vitro on Staphylococcus epidermidis. The novelty of this work is dual delivery of growth factor and antibiotic from the chitosan microparticles in a controlled manner without affecting their bioactivity. Cefazolin and vancomycin have different therapeutic concentrations for their action in vivo and therefore, two different concentrations of the drugs were used. Osteoblast cytotoxicity test concluded that cefazolin concentrations of 50 and 100μg/ml were found to have positive influence on osteoblast proliferation. A significant increase in osteoblast proliferation was observed in the presence of cefazolin and BMP-7 in comparison with BMP-7 alone group; indicating cefazolin might play a role in osteoblast proliferation. On the other hand, vancomycin concentration of 1000μg/ml was found to significantly reduce (p<0.01) osteoblast proliferation in comparison with controls. The microbial study indicated that cefazolin at a minimum concentration of 21.5μg/ml could inhibit ~85% growth of S. epidermidis, whereas vancomycin at a concentration of 30μg/ml was found to inhibit ~80% bacterial growth. PMID:27287137
Rossi, Filippo; Masi, Maurizio
This book offers a state-of-the-art overview of controlled drug delivery systems, covering the most important innovative applications. The principles of controlled drug release and the mechanisms involved in controlled release are clearly explained. The various existing polymeric drug delivery systems are reviewed, and new frontiers in material design are examined in detail, covering a wide range of polymer modification techniques. The concluding chapter is a case study focusing on use of a drug-eluting stent. The book is designed to provide the reader with a complete understanding of the mechanisms and design of controlled drug delivery systems, and to this end includes numerous step-by-step tutorials. It illustrates how chemical engineers can advance medical care by designing polymeric delivery systems that achieve either temporal or spatial control of drug delivery and thus ensure more effective therapy that eliminates the potential for both under-and overdosing.
Xu, Peipei; Wang, Ruju; Wang, Xiaohui; Ouyang, Jian
In the past few years, nanomaterial-based drug delivery systems have been applied to enhance the efficacy of therapeutics and to alleviate negative effects through the controlled delivery of targeting and releasing agents. However, few drug carriers can achieve high targeting efficacy, even when targeting modalities and surface markers are introduced. Immunological problems have also limited their wide applications. Biological drug delivery systems, such as erythrocytes, platelets, and albumin, have been extensively investigated because of their unique properties. In this review, erythrocytes, platelets, and albumin are described as efficient drug delivery systems. Their properties, applications, advantages, and limitations in disease treatment are explained. This review confirms that these systems can be used to facilitate a specific, biocompatible, and smart drug delivery.
Brown, Alyssa Marie
One of the most urgent problems in the fields of medicine and agriculture is the decreasing effectiveness of antibiotics. Once a miracle drug, antibiotics have recently become associated with the creation of antibiotic-resistant bacteria. The main limitations of these treatments include lack of both adaptability and specificity. To overcome these shortcomings of current antibiotic treatments, there has been a renewed interest in bacteriophage research. Bacteriophages are naturally-occurring viruses that lyse bacteria. They are highly specific, with each bacteriophage type lysing a narrow range of bacteria strains. Bacteriophages are also ubiquitous biological entities, populating environments where bacterial growth is supported. Just as humans are exposed to bacteria in their daily lives, we are exposed to bacteriophages as well. To use bacteriophages in practical applications, they must be delivered to the site of an infection in a controlled-release system. Two systems were studied to observe their support of bacteriophage lytic activity, as well as investigate the possibility of controlling bacteriophage release rates. First, hydrogels were studied, using crosslinking and blending techniques to achieve a range of release profiles. Second, polyanhydride microparticles were studied, evaluating release rates as a function of monomer chemistries.
Caramella, Carla M; Rossi, Silvia; Ferrari, Franca; Bonferoni, Maria Cristina; Sandri, Giuseppina
This review focuses on two formulation approaches, mucoadhesion and thermogelling, intended for prolonging residence time on vaginal mucosa of medical devices or drug delivery systems, thus improving their efficacy. The review, after a brief description of the vaginal environment and, in particular, of the vaginal secretions that strongly affect in vivo performance of vaginal formulations, deals with the above delivery systems. As for mucoadhesive systems, conventional formulations (gels, tablets, suppositories and emulsions) and novel drug delivery systems (micro-, nano-particles) intended for vaginal administration to achieve either local or systemic effect are reviewed. As for thermogelling systems, poly(ethylene oxide-propylene oxide-ethylene oxide) copolymer-based and chitosan-based formulations are discussed as thermogelling systems. The methods employed for functional characterization of both mucoadhesive and thermogelling drug delivery systems are also briefly described.
Paulsen, G.; Yoon, S.; Zacny, K.; Wettergreeng, D.; Cabrol, N. A.
The Life in the Atacama (LITA) project has a goal of demonstrating autonomous roving, sample acquisition, delivery and analysis operations in Atacama, Chile. To enable the sample handling requirement, Honeybee Robotics developed a rover-deployed, rotary-percussive, autonomous drill, called the LITA Drill, capable of penetrating to ~80 cm in various formations, capturing and delivering subsurface samples to a 20 cup carousel. The carousel has a built-in capability to press the samples within each cup, and position target cups underneath instruments for analysis. The drill and sample delivery system had to have mass and power requirements consistent with a flight system. The drill weighs 12 kg and uses less than 100 watt of power to penetrate ~80 cm. The LITA Drill auger has been designed with two distinct stages. The lower part has deep and gently sloping flutes for retaining powdered sample, while the upper section has shallow and steep flutes for preventing borehole collapse and for efficient movement of cuttings and fall back material out of the hole. The drill uses the so called 'bite-sampling' approach that is samples are taken in short, 5-10 cm bites. To take the first bite, the drill is lowered onto the ground and upon drilling of the first bite it is then retracted into an auger tube. The auger with the auger tube are then lifted off the ground and positioned next to the carousel. To deposit the sample, the auger is rotated and retracted above the auger tube. The cuttings retained on the flutes are either gravity fed or are brushed off by a passive side brush into the cup. After the sample from the first bite has been deposited, the drill is lowered back into the same hole to take the next bite. This process is repeated until a target depth is reached. The bite sampling is analogous to peck drilling in the machining process where a bit is periodically retracted to clear chips. If there is some fall back into the hole once the auger has cleared the hole, this
Alexander Jeffrey A
Full Text Available Abstract Background Many delivery-system interventions are fundamentally about change in social systems (both planned and unplanned. This systems perspective raises a number of methodological challenges for studying the effects of delivery-system change--particularly for answering questions related to whether the change will work under different conditions and how the change is integrated (or not into the operating context of the delivery system. Methods The purpose of this paper is to describe the methodological and measurement challenges posed by five key issues in delivery-system research: (1 modeling intervention context; (2 measuring readiness for change; (3 assessing intervention fidelity and sustainability; (4 assessing complex, multicomponent interventions; and (5 incorporating time in delivery-system models to discuss recommendations for addressing these issues. For each issue, we provide recommendations for how research may be designed and implemented to overcome these challenges. Results and conclusions We suggest that a more refined understanding of the mechanisms underlying delivery-system interventions (treatment theory and the ways in which outcomes for different classes of individuals change over time are fundamental starting points for capturing the heterogeneity in samples of individuals exposed to delivery-system interventions. To support the research recommendations outlined in this paper and to advance understanding of the "why" and "how" questions of delivery-system change and their effects, funding agencies should consider supporting studies with larger organizational sample sizes; longer duration; and nontraditional, mixed-methods designs. A version of this paper was prepared under contract with the Agency for Healthcare Research and Quality (AHRQ, US Department of Health and Human Services for presentation and discussion at a meeting on "The Challenge and Promise of Delivery System Research," held in Sterling, VA, on
Nielsen, Line Hagner; Petersen, Ritika Singh; Marizza, Paolo;
medium at pH 6.5 was observed. In situ intestinal perfusions were performed in rats of the Eudragit-coated ASSF-filled microcontainers and compared to a furosemide solution. At the end of the study, the small intestine was harvested from the rat and imaged under a light microscope. The absorption rate......In oral delivery, it can sometimes be necessary to employ drug delivery systems to achieve targeted delivery to the intestine. Microcontainers are polymeric, cylindrical devices in the micrometer size range (Figure 1), and are suggested as a promising oral drug delivery system ,. The purpose...... of these studies was to fabricate microcontainers in either SU-8 or biodegradable poly-L-lactic acid (PLLA), and fill the microcontainers with poorly soluble drugs. Furthermore, the application of the microcontainers as an oral drug delivery system was investigated in terms of release, in situ intestinal perfusion...
Yalin, Azer; Willson, Bryan; Defoort, Morgan; Joshi, Sachin; Reynolds, Adam
A spark delivery system for generating a spark using a laser beam is provided, and includes a laser light source and a laser delivery assembly. The laser delivery assembly includes a hollow fiber and a launch assembly comprising launch focusing optics to input the laser beam in the hollow fiber. The laser delivery assembly further includes exit focusing optics that demagnify an exit beam of laser light from the hollow fiber, thereby increasing the intensity of the laser beam and creating a spark. Other embodiments use a fiber laser to generate a spark. Embodiments of the present invention may be used to create a spark in an engine. Yet other embodiments include collecting light from the spark or a flame resulting from the spark and conveying the light for diagnostics. Methods of using the spark delivery systems and diagnostic systems are provided.
Janiffe Peres de Oliveira; Jonny Everson Scherwinski-Pereira
The objective of this work was to characterize the biochemically systemic bacterial isolated from banana plants, to evaluate the bacterial sensitivity to antibiotics, and to determine the phytotoxicity of banana shoots during in vitro proliferation. Systemic bacteria belonging to the Klebsiella and Aeromonas genera were isolated from the “Maravilha” (FHIA 01 AAAB), “Preciosa” (PV 4285 AAAB) and “Thap Maeo” (AAB) varieties and were then characterized. Tests of shoot sensitivity to antibiotics ...
Objective To establish a flow-injection chemiluminescence method for the determination of doxorubicin,epirubicin and mitoxantrone and study its reaction mechanism.Methods In alkaline medium,chemiluminescence of luminol-potassium permanganate system could be inhibited obviously by anthracycline antibiotics.Combined with flow-injection technique,a new chemiluminescence method for determining the anthracycline antibiotics was set up.The chemiluminescence mechanism of the luminol-potassium permanganate system w...
Full Text Available This paper reviews constructed drug delivery systems applying osmotic principles for controlled drugrelease from the formulation. Osmotic devices which are tablets coated with walls of controlled porosityare the most promising strategy based systems for controlled drug delivery. In contrast to commontablets, these pumps provide constant (zero order drug release rate. When these systems are exposed towater, low levels of water soluble additive is leached from polymeric material i.e. semipermeablemembrane and drug releases in a controlled manner over an extended period of time. The main clinicalbenefits of oral osmotic drug delivery system are their ability to improve treatment tolerability andpatient compliance. These advantages are mainly driven by the capacity to deliver drugs in a sustainedmanner, independent of the drug chemical properties, of the patient’s physiological factors or followingfood intake. This review brings out the theoretical concept of drug delivery, history, advantages anddisadvantages of the delivery systems, types of oral osmotic drug delivery systems, factors affecting thedrug delivery system and marketed products.
Kim, Junbeum; Xu, Ming; Kahhat, Ramzy; Allenby, Braden; Williams, Eric
We attempted to design and assess an example of a sustainable networked delivery (SND) system: a hybrid business-to-consumer book delivery system. This system is intended to reduce costs, achieve significant reductions in energy consumption, and reduce environmental emissions of critical local pollutants and greenhouse gases. The energy consumption and concomitant emissions of this delivery system compared with existing alternative delivery systems were estimated. We found that regarding energy consumption, an emerging hybrid delivery system which is a sustainable networked delivery system (SND) would consume 47 and 7 times less than the traditional networked delivery system (TND) and e-commerce networked delivery system (END). Regarding concomitant emissions, in the case of CO2, the SND system produced 32 and 7 times fewer emissions than the TND and END systems. Also the SND system offer meaningful economic benefit such as the costs of delivery and packaging, to the online retailer, grocery, and consumer. Our research results show that the SND system has a lot of possibilities to save local transportation energy consumption and delivery costs, and reduce environmental emissions in delivery system.
Kim, Junbeum; Xu, Ming; Kahhat, Ramzy; Allenby, Braden; Williams, Eric
We attempted to design and assess an example of a sustainable networked delivery (SND) system: a hybrid business-to-consumer book delivery system. This system is intended to reduce costs, achieve significant reductions in energy consumption, and reduce environmental emissions of critical local pollutants and greenhouse gases. The energy consumption and concomitant emissions of this delivery system compared with existing alternative delivery systems were estimated. We found that regarding energy consumption, an emerging hybrid delivery system which is a sustainable networked delivery system (SND) would consume 47 and 7 times less than the traditional networked delivery system (TND) and e-commerce networked delivery system (END). Regarding concomitant emissions, in the case of CO2, the SND system produced 32 and 7 times fewer emissions than the TND and END systems. Also the SND system offer meaningful economic benefit such as the costs of delivery and packaging, to the online retailer, grocery, and consumer. Our research results show that the SND system has a lot of possibilities to save local transportation energy consumption and delivery costs, and reduce environmental emissions in delivery system. PMID:19209604
Krukowski, Z H; Al-Sayer, H M; Reid, T M; Matheson, N A
Quantitative bacteriology in peritoneal exudate was studied in 40 patients with generalized peritonitis of small intestinal, appendicular or colonic origin. Bacterial growth kinesis was measured in 28 of the patients. Systemic antibiotics given before operation resulted in a significant reduction in both the concentration and growth rate of viable bacteria in the peritoneal fluid. Lavage of the peritoneal cavity with saline resulted in a further reduction in growth rate in patients given pre-operative systemic antibiotics by an effect attributable to simple dilution. In contrast, peritoneal lavage with tetracycline (1 mg/ml) resulted in complete inhibition of bacterial growth in the residual peritoneal fluid. These observations support the policy of giving systemic antibiotics to patients with generalized peritonitis as soon as the diagnosis has been made and provide bacteriological evidence for the value of peroperative antibiotic peritoneal lavage.
ZHANG Lixia; LIN Nengxing; HUANG Changzheng; CHEN Hongxiang; LIN Yun; TU Yating
To study the relationship between mutation of the inverted repeat sequence (IR) in the multiple transferable resistant system (mtr) of Neisseria gonorrhoeae (NG) and itsmultiple antibiotic resistance, minimal inhibitory concentrations (MICs) for the clinically isolated strains were tested by agar-dilution-method. The mtr system's IR gene of NG was sequenced after amplification by polymerase chain reaction (PCR). Either two susce ptive or five penicillin-resistant strains had no base mutation in IR gene, while all of the 13 strains with multiple-antibiotic-resistance had a singlebase deletion (A/T). The result suggests that a single-base deletion of the thirteen-base IR sequence in mtr system of NG might result in multiple antibiotic resistance but is not associated with single antibiotic resistance.
Full Text Available Abstract Cancer vaccines are the promising tools in the hands of the clinical oncologist. Many tumor-associated antigens are excellent targets for immune therapy and vaccine design. Optimally designed cancer vaccines should combine the best tumor antigens with the most effective immunotherapy agents and/or delivery strategies to achieve positive clinical results. Various vaccine delivery systems such as different routes of immunization and physical/chemical delivery methods have been used in cancer therapy with the goal to induce immunity against tumor-associated antigens. Two basic delivery approaches including physical delivery to achieve higher levels of antigen production and formulation with microparticles to target antigen-presenting cells (APCs have demonstrated to be effective in animal models. New developments in vaccine delivery systems will improve the efficiency of clinical trials in the near future. Among them, nanoparticles (NPs such as dendrimers, polymeric NPs, metallic NPs, magnetic NPs and quantum dots have emerged as effective vaccine adjuvants for infectious diseases and cancer therapy. Furthermore, cell-penetrating peptides (CPP have been known as attractive carrier having applications in drug delivery, gene transfer and DNA vaccination. This review will focus on the utilization of different vaccine delivery systems for prevention or treatment of cancer. We will discuss their clinical applications and the future prospects for cancer vaccine development.
Full Text Available Niosomes are non-ionic surfactant vesicles inclosing an aqueous phase and a wide range of molecules could be encapsulated within aqueous spaces of lipid membrane vesicles. They are microscopic lamellar structures formed on the admixture of a non-ionic surfactant, cholesterol and phosphate with subsequent hydration in aqueous media. Niosomes belongs to novel drug delivery system which offers a large number of advantages over other conventional and vesicular delivery systems. Namely they are the targeted drug delivery system which showing reduction of dose, stability and compatibility of non-ionic surfactants, easy modification, delayed clearance, suitability for a wide range of Active Pharmaceutical Agents.
Some gas delivery systems used in pulmonary ventilation scanning are unable to satisfactorily supply 133Xe gas to bed-ridden patients. A mechanical gas valve assembly to control the flow of gas in such systems was constructed. A commercially produced 133Xe gas delivery system when fitted with the new assembly was able to ventilate almost all patients whereas previously this could be achieved with approximately only 50% of patients
Jaimini Manish; Joshi Vishalkumar
The purpose of this review on floating drug delivery systems is the recent literature with mechanism to achieve gastric retention by floatation. Gastroretentive drug delivery system have advantages besides providing better bioavailability to poorly absorbed drugs and a required release profile thus attracting interest of pharmaceutical formulation. These systems are useful to several problems encountered during the development of a pharmaceutical dosage form. The objectives of the review disc...
Alexander Amit; Sharma Sharad; Ajazuddin,; Khan Mohammed Junaid; Swarna
Bioadhesion is an interfacial phenomenon in which two materials, at least one of which is biological, are held together by means of interfacial forces. When the associated biological system is mucous, it is called mucoadhesion. This property of certain polymeric systems have got place in the drug delivery research in order to prolong contact time in the various mucosal route of drug administration, as the ability to maintain a delivery system at a particular location for an extended period of...
Full Text Available The abundance of two-component systems (TCSs in Streptomyces coelicolor A3(2 genome indicates their importance in the physiology of this soil bacteria. Currently, several TCSs have been related to antibiotic regulation, and the purpose in this study was the characterization of five TCSs, selected by sequence homology with the well-known absA1A2 system, that could also be associated with this important process. Null mutants of the five TCSs were obtained and two mutants (ΔSCO1744/1745 and ΔSCO4596/4597/4598 showed significant differences in both antibiotic production and morphological differentiation, and have been renamed as abr (antibiotic regulator. No detectable changes in antibiotic production were found in the mutants in the systems that include the ORFs SCO3638/3639, SCO3640/3641 and SCO2165/2166 in any of the culture conditions assayed. The system SCO1744/1745 (AbrA1/A2 was involved in negative regulation of antibiotic production, and acted also as a negative regulator of the morphological differentiation. By contrast, the system SCO4596/4597/4598 (AbrC1/C2/C3, composed of two histidine kinases and one response regulator, had positive effects on both morphological development and antibiotic production. Microarray analyses of the ΔabrC1/C2/C3 and wild-type transcriptomes revealed downregulation of actII-ORF4 and cdaR genes, the actinorhodin and calcium-dependent antibiotic pathway-specific regulators respectively. These results demonstrated the involvement of these new two-component systems in antibiotic production and morphological differentiation by different approaches. One is a pleiotropic negative regulator: abrA1/A2. The other one is a positive regulator composed of three elements, two histidine kinases and one response regulator: abrC1/C2/C3.
Kadam Shashikant M; Kadam.S.R; Patil.U.S; Ratan G N; Jamkandi.V.G.
Controlled release (CR) dosage forms have been extensively used to improve therapy with many important drugs. Several approaches are currently utilized in prolongation of gastric residence time, including floating drug delivery system, swelling and expanding system, polymeric bioadhesive system, modified shape system, high density system and other delayed gastric emptying devices. However, the development processes are faced with several physiological difficulties such as the inability to res...
Full Text Available Gene delivery systems can be divided to two major types: vector-based (either viral vector or non-viral vector and physical delivery technologies. Many physical carriers, such as electroporation, gene gun, ultrasound start to be proved to have the potential to enable gene therapy. A relatively new physical delivery technology for gene delivery consists of microneedles (MNs, which has been studied in many fields and for many molecule types and indications. Microneedles can penetrate the stratum corneum, which is the main barrier for drug delivery through the skin with ease of administration and without significant pain. Many different kinds of MNs, such as metal MNs, coated MNs, dissolving MNs have turned out to be promising in gene delivery. In this review, we discussed the potential as well as the challenges of utilizing MNs to deliver nucleic acids for gene therapy. We also proposed that a combination of MNs and other gene delivery approaches may lead to a better delivery system for gene therapy.
Full Text Available The reason of writing this research article on gastro retentive drug delivery systems was to gather the recent literature with special focus on various gastro retentive approaches that have recently become leading methodologies in the field of site-specific orally administered controlled release drug delivery. In order to identify with various physiological difficulties to achieve gastric retention, we have summarized important factors controlling gastric retention. Afterwards, we have reviewed various gastro retentive approaches designed and developed until now, i.e. microspheres, microcapsules, floating gel beads, floating matrix tablets and in-situ gel, with advantages and limitations of gastro retentive drug delivery systems in detail.
Edwards, Clifford H.
This study focused on normal junior high school students in the natural school environment. Its purpose was to determine if different token delivery systems would differentially affect the disruptive behavior patterns of students in the normal classroom. (Author/RK)
van Pijkeren, Jan Peter
Bacteria-mediated transfer of plasmid DNA to mammalian cells (bactofection) has been shown to have significant potential as an approach to express heterologous proteins in various cell types. This is achieved through entry of the entire bacterium into cells, followed by release of plasmid DNA. In a murine model, we show that Listeria monocytogenes can invade and spread in tumors, and establish the use of Listeria to deliver genes to tumors in vivo. A novel approach to vector lysis and release of plasmid DNA through antibiotic administration was developed. Ampicillin administration facilitated both plasmid transfer and safety control of vector. To further improve on the gene delivery system, we selected a Listeria monocytogenes derivative that is more sensitive to ampicillin, and less pathogenic than the wild-type strain. Incorporation of a eukaryotic-transcribed lysin cassette in the plasmid further increased bacterial lysis. Successful gene delivery of firefly luciferase to growing tumors in murine models and to patient breast tumor samples ex vivo was achieved. The model described encompasses a three-phase treatment regimen, involving (1) intratumoral administration of vector followed by a period of vector spread, (2) systemic ampicillin administration to induce vector lysis and plasmid transfer, and (3) systemic administration of combined moxifloxacin and ampicillin to eliminate systemic vector. For the first time, our results reveal the potential of Listeria monocytogenes for in vivo gene delivery.
Taksande Jayshree B; Trivedi Rashmi V; Mahore Jayashri G; Wadher Kamlesh J; Umekar Milind J.
Oral delivery of poorly water-soluble drugs creates critical problem for their formulation as 35- 40% of new active pharmaceutical ingredients have poor water solubility and frequently associated with low bioavailability. Recently much attention has been given to lipid-based formulation with particular emphasis on self emulsifying drug delivery system (SEDDS) to improve the oral bioavailability. These can exist in either liquid or solid states. Self-emulsifying system formulation mainly depen...
Reshmy Rajan; Shoma Jose; V P Biju Mukund; Deepa T Vasudevan
Transdermal administration of drugs is generally limited by the barrier function of the skin. Vesicular systems are one of the most controversial methods for transdermal delivery of active substances. The interest in designing transdermal delivery systems was relaunched after the discovery of elastic vesicles like transferosomes, ethosomes, cubosomes, phytosomes, etc. This paper presents the composition, mechanisms of penetration, manufacturing and characterization methods of transferosomes a...
Pallavi Pal; Vijay Sharma; Lalit Singh
Oral controlled release delivery systems are programmed to deliver the drug in predictable time frame that will increase the efficacy and minimize the adverse effects and increase the bioavailability of drugs. Oral route is considered mostnatural, uncomplicated, convenient and safe due to its ease of administration, patient acceptance, and cost-effective manufacturing process.Floating Drug delivery system are designed to prolong the gastric residence time after oral administration, at particu...
Highlights significance of designing service delivery system, explains the integral role of customer in service production process, stresses the importance of customer-organisation interface, lists important ingredients of service package to be considered while designing customer interface, enumerates various dimensions of customer interface which can be positively made use of in design of service production and delivery system, discusses various ways and means of inducing and enhancing custo...
Tayal Ayushi; Jamil Faraz; Sharma Ritika; Sharma Saurabh
Oral route still remains the favorite route of drug administration in many diseases and till today it is the first wayinvestigated in the development of new dosage forms. Approximately 40 per cent of new drug candidates have poor water solubility and the oral delivery ofsuch drugs is frequently associated with implications of low bioavailability, high intra and inter-subjectvariability, and lack of dose proportionality. Bioavailability problem of lipophillic drugs can be solved byformation of...
Ortiz-Mellet, Carmen; García Fernández, José M.; Benito, Juan M.
Cyclodextrin (CD) history has been largely dominated by their unique ability to form inclusion complexes with guests fitting in their hydrophobic cavity. Chemical funcionalization was soon recognized as a powerful mean for improving CD applications in a wide range of fields, including drug delivery, sensing or enzyme mimicking. However, 100 years after their discovery, CDs are still perceived as novel nanoobjects of undeveloped potential. This critical review provides an overview of different...
Ingerslev, Flemming; Toräng, Lars; Loke, M.-L.;
The primary aerobic and anaerobic biodegradability at intermediate concentrations (50-5000 mug/l) of the antibiotics olaquindox (OLA), metronidazole (MET), tylosin (TYL) and oxytetracycline (OTC) was studied in a simple shake flask system simulating the conditions in surface waters. The purpose...... of the study was to provide rate data for primary biodegradation in the scenario where antibiotics pollute surface waters as a result of run-off from arable land. The source of antibiotics may be application of manure as fertilizer or excreta of grazing animals. Assuming first-order degradation kinetics...... substances. The biodegradation behaviour was influenced by neither the concentrations of antibiotics nor the time of the year and location for sampling of surface water. Addition of 1 g/l of sediment or 3 mg/l of activated sludge from wastewater treatment increased the biodegradation potential which...
Pulcini, Céline; Bush, Karen; Craig, William A;
In view of the alarming spread of antimicrobial resistance in the absence of new antibiotics, this study aimed at assessing the availability of potentially useful older antibiotics. A survey was performed in 38 countries among experts including hospital pharmacists, microbiologists, and infectious...... disease specialists in Europe, the United States, Canada, and Australia. An international expert panel selected systemic antibacterial drugs for their potential to treat infections caused by resistant bacteria or their unique value for specific criteria. Twenty-two of the 33 selected antibiotics were...... available in fewer than 20 of 38 countries. Economic motives were the major cause for discontinuation of marketing of these antibiotics. Fourteen of 33 antibiotics are potentially active against either resistant Gram-positive or Gram-negative bacteria. Urgent measures are then needed to ensure better...
Simulation modelling is a powerful analysis tool used to evaluate complex systems or processes. The modeling concept was utilized to evaluate the performance of the Waste Isolation Pilot Plant (WIPP) transportation and delivery system. The model will assist in analyzing the responsiveness of the components in the system to the variations in waste generation schedule, system failures, and material handling options. (author)
Full Text Available Novel drug delivery systems present an opportunity for formulation scientists to overcome the many challenges associated with antihypertensive drug therapy, thereby improving the management of patients with hypertension. Currently available Anti-hypertensive drugs can be classified into these categories: ACE inhibitors, angiotensin antagonist, calcium channel blocker, diuretics, central sympathomimetics, á- adernergic blocker, vasodilator, â-adernergic blocker. Most of these drugs bear some significant drawbacks such as relatively short half-life, low bioavailability, poor permeability and undesirable side effects. Efforts have been made to design drug delivery systems for anti hypertensive drugs to: a reduce the dosing frequency, b increase the bioavailability, c deliver them to the target cells selectively with minimal side effects. This paper provides a comprehensive review of the various anti hypertensive drug delivery systems that have been developed for achieving sustained drug release kinetics, and for addressing formulation difficulties such as poor solubility, stability and drug entrapment. The physicochemical properties and the in vitro/in vivo performances of various system such as such as sustained release tablets, ceramic implants, nanoparticles, nanocontainers, liposomes, emulsomes, aspasomes, microemulsions, nanopowders and PheroidTM are summarised. This review highlights the significant potential that novel drug delivery systems have for the future effective treatment of hypertensive patients on anti-hypertensive drug therapy.
Fulzele, Suniket V; Satturwar, Prashant M; Dorle, Avinash K
The purpose of this study was to investigate the in vitro-in vivo degradation and tissue compatibility of three novel biopolymers viz. polymerized rosin (PR), glycerol ester of polymerized rosin (GPR) and pentaerythritol ester of polymerized rosin (PPR) and study their potential as implant matrix for the delivery of ciprofloxacin hydrochloride. Free films of polymers were used for in vitro degradation in PBS (pH 7.4) and in vivo in rat subcutaneous model. Sample weight loss, molecular weight decline, and morphological changes were analyzed after periodic intervals (30, 60, and 90 days) to monitor the degradation profile. Biocompatibility was evaluated by examination of the inflammatory tissue response to the implanted films on postoperative days 7, 14, 21, and 28. Furthermore, direct compression of dry blends of various polymer matrices with 20%, 30%, and 40% w/w drug loading was performed to investigate their potential for implant systems. The implants were characterized in terms of porosity and ciprofloxacin release. Biopolymer films showed slow rate of degradation, in vivo rate being faster on comparative basis. Heterogeneous bulk degradation was evident with the esterified products showing faster rates than PR. Morphologically all the films were stiff and intact with no significant difference in their appearance. The percent weight remaining in vivo was 90.70 +/- 6.2, 85.59 +/- 5.8, and 75.56 +/- 4.8 for PR, GPR, and PPR films respectively. Initial rapid drop in Mw was demonstrated with nearly 20.0% and 30.0% decline within 30 days followed by a steady decline to nearly 40.0% and 50.0% within 90 days following in vitro and in vivo degradation respectively. Biocompatibility demonstrated by acute and subacute tissue reactions showed minimal inflammatory reactions with prominent fibrous encapsulation and absence of necrosis demonstrating good tissue compatibility to the extent evaluated. All implants showed erosion and increase in porosity that affected the drug
Garg, Tarun; Rath, Goutam; Goyal, Amit Kumar
In this paper, we provide an overview an extensive range of colloidal drug delivery systems with special focus on vesicular and particulates systems that are being used in research or might be potentially useful as carriers systems for drug or active biomolecules or as cell carriers with application in the therapeutic field. We present some important examples of commercially available drug delivery systems with applications in research or in clinical fields. This class of systems is widely used due to excellent drug targeting, sustained and controlled release behavior, higher entrapment efficiency of drug molecules, prevention of drug hydrolysis or enzymatic degradation, and improvement of therapeutic efficacy. These characteristics help in the selection of suitable carrier systems for drug, cell, and gene delivery in different fields.
Milan Agrawal et al
Full Text Available The parenteral administration route is the most effective and common form of delivery for active drug substances with poor bioavailability and the drugs with a narrow therapeutic index. Drug delivery technology that can reduce the total number of injection throughout the drug therapy period will be truly advantageous not only in terms of compliance, but also to improve the quality of the therapy and also may reduce the dosage frequency. Such reduction in frequency of drug dosing is achieved by the use of specific formulation technologies that guarantee the release of the active drug substance in a slow and predictable manner. The development of new injectable drug delivery system has received considerable attention over the past few years. A number of technological advances have been made in the area of parenteral drug delivery leading to the development of sophisticated systems that allow drug targeting and the sustained or controlled release of parenteral medicines.
Amler, Evžen; Filová, Eva; Buzgo, Matej; Prosecká, Eva; Rampichová, Michala; Nečas, Alois; Nooeaid, Patcharakamon; Boccaccini, Aldo R
A wide range of drug-delivery systems are currently attracting the attention of researchers. Nanofibers are very interesting carriers for drug delivery. This is because nanofibers are versatile, flexible, nanobiomimetic and similar to extracellular matrix components, possible to be functionalized both on their surface as well as in their core, and also because they can be produced easily and cost effectively. There have been increasing attempts to use nanofibers in the construction of a range of tissues, including cartilage and bone. Nanofibers have also been favorably engaged as a drug-delivery system in cell-free scaffolds. This short overview is devoted to current applications and to further perspectives of nanofibers as drug-delivery devices in the field of cartilage and bone regeneration, and also in osteochondral reconstruction. PMID:24978465
Christophersen, Philip Carsten; Fano, Mathias; Saaby, Lasse;
are summarized. Additionally, the paper provides an overview of recent studies on characterization of solid drug carriers for peptide/protein drugs, drug distribution in particles, drug release and stability in simulated GI fluids, as well as the absorption of peptide/protein drugs in cell-based models. The use......Oral drug delivery is a preferred route because of good patient compliance. However, most peptide/ protein drugs are delivered via parenteral routes because of the absorption barriers in the gastrointestinal (GI) tract such as enzymatic degradation by proteases and low permeability acrossthe...... biological membranes. To overcome these barriers, different formulation strategies for oral delivery of biomacromolecules have been proposed, including lipid based formulations and polymer-based particulate drug delivery systems (DDS). The aim of this review is to summarize the existing knowledge about oral...
Li, Ping; Nielsen, Hanne Mørck; Müllertz, Anette
INTRODUCTION: In order to successfully develop lipid-based drug delivery systems (DDS) for oral administration of peptides and proteins, it is important to gain an understanding of the colloid structures formed by these DDS, the mode of peptide and protein incorporation as well as the mechanism...... by which intestinal absorption of peptides and proteins is promoted. AREAS COVERED: The present paper reviews the literature on lipid-based DDS, employed for oral delivery of peptides and proteins and highlights the mechanisms by which the different lipid-based carriers are expected to overcome the two...... most important barriers (extensive enzymatic degradation and poor transmucosal permeability). This paper also gives a clear-cut idea about advantages and drawbacks of using different lipidic colloidal carriers ((micro)emulsions, solid lipid core particles and liposomes) for oral delivery of peptides...
Lahoti S.R.; Syed Iftequar; Sabina M; Dehghan M.H.; Shoaib S; Mohiuddin S
The reason of writing this research article on gastro retentive drug delivery systems was to gather the recent literature with special focus on various gastro retentive approaches that have recently become leading methodologies in the field of site-specific orally administered controlled release drug delivery. In order to identify with various physiological difficulties to achieve gastric retention, we have summarized important factors controlling gastric retention. Afterwards, we have review...
Torchilin, Vladimir P.
The use of nanoparticulate pharmaceutical drug delivery systems (NDDSs) to enhance the in vivo effectiveness of drugs is now well established. The development of multifunctional and stimulus-sensitive NDDSs is an active area of current research. Such NDDSs can have long circulation times, target the site of the disease and enhance the intracellular delivery of a drug. This type of NDDS can also respond to local stimuli that are characteristic of the pathological site by, for example, releasin...
Jose S; Dhanya K; Cinu T; Aleykutty N
Targeted delivery of drugs to colon has the potential for local treatment of a variety of colonic diseases. The main objective of the study was to develop a multiparticulate system containing chitosan microspheres for the colon targeted delivery of ondansetron for the treatment of irritable bowel syndrome. This work combines pH-dependent solubility of eudragit S-100 polymers and microbial degradability of chitosan polymers. Chitosan microspheres containing ondansetron were prepared by emulsio...
Modi Kushal; Modi Monali; Mishra Durgavati; Panchal Mittal; Sorathiya Umesh; Shelat Pragna
Oral drug delivery is the most preferred and convenient option as the oral route provides maximum active surface area among all drug delivery system for administration of various drugs. The attractiveness of these dosage forms is due to awareness to toxicity and ineffectiveness of drugs when administered by oral conventional method in the form of tablets and capsules. Usually conventional dosage form produces wide range of fluctuation in drug concentration in the bloodstream and tissues with ...
Yadav Nisha R.
Full Text Available Probiotic are bacteria that help to maintain the natural balance of the microorganism in the intestine. Probiotic is gaining its popularity as an alternate approach for the healthcare management and till now has proofed its therapeutic indication in many simple to complex diseases. Diverse mechanism of action and being a living organism are two main advantages. However there are several drawbacks also associated with this new emerging therapeutic area. Probiotic strain identification, characterization, screening, understanding its mechanism of action for particular disease which is seeking much attention. The primary aim associated with the probiotic delivery is maintaining bacteria viability during product manufacturing and during storage. Several approaches such as microencapsulation and use of suitable biocompatible material have been studied and still under continuous exploration. Along with the regulatory aspect associated with the probiotics in this review details on current research in the area of exploring indication and advancement in delivery technologies has been covered. Review concluded with rational recommendations of each aspect of probiotics.
Misak, Heath E; Asmatulu, Ramazan; Gopu, Janani S; Man, Ka-Poh; Zacharias, Nora M; Wooley, Paul H; Yang, Shang-You
A novel drug delivery system incorporating human serum albumin, poly(lactic-co-glycolic acid, magnetite nanoparticles, and therapeutic agent(s) was developed for potential application in the treatment of diseases such as rheumatoid arthritis and skin cancer. An oil-in-oil emulsion/solvent evaporation (O/OSE) method was modified to produce a drug delivery system with a diameter of 0.5–2 μm. The diameter was mainly controlled by adjusting the viscosity of albumin in the discontinuous phase of the O/OSE method. The drug-release study showed that the release of drug and albumin was mostly dependent on the albumin content of the drug delivery system, which is very similar to the drug occlusion-mesopore model. Cytotoxicity tests indicated that increasing the albumin content in the drug delivery system increased cell viability, possibly due to the improved biocompatibility of the system. Overall, these studies show that the proposed system could be a viable option as a drug delivery system in the treatment of many illnesses, such as rheumatoid arthritis, and skin and breast cancers. PMID:24106002
A. S. Chudasama
Full Text Available Nevirapine is a highly lipophilic and water insoluble non-nucleoside reverse transcriptase inhibitor used for the treatment of HIV-1 infection. Lymphoid tissue constitutes the major reservoir of HIV virus and infected cells in HIV-infected patients. Self-emulsifying drug delivery system, using long chain triglycerides, is a popular carrier of drugs due to their ability to transport lipophilic drugs into the lymphatic circulation. However, HIV/AIDS patients experience a variety of functional and anatomical abnormalities in gastrointestinal tract that result in diarrhoea and nutrient malabsorption. Medium chain triglycerides are readily absorbed from the small bowel under conditions in which the absorption of long chain triglycerides is impaired. Therefore, nevirapine self-emulsifying drug delivery system containing medium chain fatty acid, caprylic acid and a solubilizer, Soluphor ® P (2-pyrrolidone was developed and found to be superior to the marketed conventional suspension with respect to in vitro diffusion and ex vivo intestinal permeability. This self-emulsifying drug delivery system has now been further investigated for in vivo absorption in an animal model. The contribution of caprylic acid and Soluphor ® P on in vivo absorption of nevirapine was also studied in the present study. The bioavailability of nevirapine from self-emulsifying drug delivery system, after oral administration, was 2.69 times higher than that of the marketed suspension. The improved bioavailability could be due to absorption of nevirapine via both portal and intestinal lymphatic routes. The study indicates that medium chain or structured triglycerides can be a better option to develop self-emulsifying drug delivery system for lipophilic and extensively metabolised drugs like nevirapine for patients with AIDS-associated malabsorption.
Chudasama, A S; Patel, V V; Nivsarkar, M; Vasu, Kamala K; Shishoo, C J
Nevirapine is a highly lipophilic and water insoluble non-nucleoside reverse transcriptase inhibitor used for the treatment of HIV-1 infection. Lymphoid tissue constitutes the major reservoir of HIV virus and infected cells in HIV-infected patients. Self-emulsifying drug delivery system, using long chain triglycerides, is a popular carrier of drugs due to their ability to transport lipophilic drugs into the lymphatic circulation. However, HIV/AIDS patients experience a variety of functional and anatomical abnormalities in gastrointestinal tract that result in diarrhoea and nutrient malabsorption. Medium chain triglycerides are readily absorbed from the small bowel under conditions in which the absorption of long chain triglycerides is impaired. Therefore, nevirapine self-emulsifying drug delivery system containing medium chain fatty acid, caprylic acid and a solubilizer, Soluphor(®) P (2-pyrrolidone) was developed and found to be superior to the marketed conventional suspension with respect to in vitro diffusion and ex vivo intestinal permeability. This self-emulsifying drug delivery system has now been further investigated for in vivo absorption in an animal model. The contribution of caprylic acid and Soluphor(®) P on in vivo absorption of nevirapine was also studied in the present study. The bioavailability of nevirapine from self-emulsifying drug delivery system, after oral administration, was 2.69 times higher than that of the marketed suspension. The improved bioavailability could be due to absorption of nevirapine via both portal and intestinal lymphatic routes. The study indicates that medium chain or structured triglycerides can be a better option to develop self-emulsifying drug delivery system for lipophilic and extensively metabolised drugs like nevirapine for patients with AIDS-associated malabsorption. PMID:25035533
Full Text Available Drug delivery system relates to the production of a drug, its delivery medium, and the way of administration. Drug delivery systems are even used for administering nitroglycerin. Transdermal drug delivery system is the system in which the delivery of the active ingredients of the drug occurs by the means of skin. Various types of transdermal patches are used. There are various methods to enhance the transdermal drug delivery system. But using microfabricated microneedles drugs are delivered very effectively to skin patch. There has been great progress in the Transdermal drug delivery system for the delivery of different forms and our aim is to collect the information about what progressed have done in Transdermal drug delivery system and developments in Transdermal drug delivery systems in theoretical form. Also, to collect the information about the advantages and application of the Transdermal drug delivery systems.
Full Text Available With the discovery of insulin in 1922, identification and commercialization of potential protein and peptide drugs have been increased. Since then, research and development to improve the means of delivering protein therapeutics to patients has begun. The research efforts have followed two basic pathways: One path focused on noninvasive means of delivering proteins to the body and the second path has been primarily aimed at increasing the biological half-life of the therapeutic molecules. The search for approaches that provide formulations that are stable, bioavailable, readily manufacturable, and acceptable to the patient, has led to major advances in the development of nasal and controlled release technology, applicable to every protein or peptide. In several limited cases, sustained delivery of peptides and proteins has employed the use of polymeric carriers. More successes have been achieved by chemical modification using amino acid substitutions, protein pegylation or glycosylation to improve the pharmacodynamic properties of certain macromolecules and various delivery systems have been developed like the prolease technology, nano-particulate and microparticulate delivery systems, and the mucoadhesive delivery of peptides. The needle and syringe remain the primary means of protein delivery. Major hurdles remain in order to overcome the combined natural barriers of drug permeability, drug stability, pharmacokinetics, and pharmacodynamics of protein therapeutics. In our present review we have tried to compile some recent advances in protein and peptide drug delivery systems.
Szabo, Peter; Zelko, Romana
Nano drug delivery systems are considered as useful means to remedy the problems of drugs of poor solubility, permeability and bioavailability, which became one of the most troublesome questions of the pharmaceutical industry. Different types of nanosized drug delivery systems have been developed and investigated for oral administration, providing auspicious solutions for drug development. In this paper nanosized drug delivery systems intended for oral administration are discussed based on the chemical nature of the carrier of drug molecules. Lipid nanoparticles comprising solid lipid nanoparticles, improved nanostructured lipid carriers and nanostructured silica- lipid hybrid particles have become popular in the formulation of lipophilic drugs of poor oral bioavailability. Polymeric nanoparticles including nanospheres and nanocapsules and polymeric fibrous systems have also emerged as potential drug delivery systems owing to their unique structure. The feasibility of surface functionalization of mesoporous materials and gold nanoparticles enables high level of control over particle characteristics making inorganic nanoparticles an exceptional formulation approach. The authors paid particular attention to the functionality-related stability of the reviewed delivery systems.
Pichichero, Michael E
Adjuvants have been common additions to vaccines to help facilitate vaccine delivery. With advancements in vaccine technology, several adjuvants which activate immune specific responses have emerged. Available data show these adjuvants elicit important immune responses in both healthy and immunocompromised populations, as well as the elderly. Guidelines for the use and licensure of vaccine adjuvants remain under discussion. However, there is a greater understanding of the innate and adaptive immune response, and the realization of the need for immune specific adjuvants appears to be growing. This is a focused review of four adjuvants currently in clinical trial development: ASO4, ASO2A, CPG 7907, and GM-CSF. The vaccines including these adjuvants are highly relevant today, and are expected to reduce the disease burden of cervical cancer, hepatitis B and malaria. PMID:18398303
Janaswamy, Srinivas; Youngren, Susanne R. (Purdue)
Nutraceuticals are important due to their inherent health benefits. However, utilization and consumption are limited by their poor water solubility and instability at normal processing and storage conditions. Herein, we propose an elegant and novel approach for the delivery of nutraceuticals in their active form using hydrocolloid matrices that are inexpensive and non-toxic with generally recognized as safe (GRAS) status. Iota-carrageenan and curcumin have been chosen as models of hydrocolloid and nutraceutical compounds, respectively. The iota-carrageenan network maintains a stable organization after encapsulating curcumin molecules, protects them from melting and then releases them in a sustained manner. These findings lay a strong foundation for developing value-added functional and medicinal foods.
Johnson, Noah R; Wang, Yadong
Coacervates represent an exciting new class of drug delivery vehicles, developed in the past decade as carriers of small molecule drugs and proteins. This review summarizes several well-described coacervate systems, including: i) elastin-like peptides for delivery of anticancer therapeutics; ii) heparin-based coacervates with synthetic polycations for controlled growth factor delivery; iii) carboxymethyl chitosan aggregates for oral drug delivery; iv) Mussel adhesive protein and hyaluronic acid coacervates. Coacervates present advantages in their simple assembly and easy incorporation into tissue engineering scaffolds or as adjuncts to cell therapies. They are also amenable to functionalization such as for targeting or for enhancing the bioactivity of their cargo. These new drug carriers are anticipated to have broad applications and noteworthy impact in the near future.
Hu, Quanyin; Sun, Wujin; Wang, Chao; Gu, Zhen
Combination chemotherapy is widely exploited for enhanced cancer treatment in the clinic. However, the traditional cocktail administration of combination regimens often suffers from varying pharmacokinetics among different drugs. The emergence of nanotechnology offers an unparalleled opportunity for developing advanced combination drug delivery strategies with the ability to encapsulate various drugs simultaneously and unify the pharmacokinetics of each drug. This review surveys the most recent advances in combination delivery of multiple small molecule chemotherapeutics using nanocarriers. The mechanisms underlying combination chemotherapy, including the synergistic, additive and potentiation effects, are also discussed with typical examples. We further highlight the sequential and site-specific co-delivery strategies, which provide new guidelines for development of programmable combination drug delivery systems. Clinical outlook and challenges are also discussed in the end.
Full Text Available Ophthalmic drug delivery is one of the most attractive and challenging research area for pharmaceutical scientists and ophthalmologists. Absorption of an ophthalmic drug in conventional dosage forms is seriously limited by physiological conditions. The use of nonionic or ionic biodegradable polymers in aqueous solutions and colloidal dosage forms such as liposomes, nanoparticles, nanocapsules, microspheres, microcapsules, microemulsions, and dendrimers has been studied to overcome the problems mentioned above. Dendrimers are a new class of polymeric materials. The unique nanostructured architecture of dendrimers has been studied to examine their role in delivery of therapeutics and imaging agents. Dendrimers can enhance drug’s water solubility, bioavailability, and biocompatibility and can be applied for different routes of drug administration successfully. Permeability enhancer properties of dendrimers were also reported. The use of dendrimers can also reduce toxicity versus activity and following an appropriate application route they allow the delivery of the drug to the targeted site and provide desired pharmacokinetic parameters. Therefore, dendrimeric drug delivery systems are of interest in ocular drug delivery. In this review, the limitations related to eye’s unique structure, the advantages of dendrimers, and the potential applications of dendrimeric systems to ophthalmology including imaging, drug, peptide, and gene delivery will be discussed.
Yavuz, Burçin; Pehlivan, Sibel Bozdağ; Unlü, Nurşen
Ophthalmic drug delivery is one of the most attractive and challenging research area for pharmaceutical scientists and ophthalmologists. Absorption of an ophthalmic drug in conventional dosage forms is seriously limited by physiological conditions. The use of nonionic or ionic biodegradable polymers in aqueous solutions and colloidal dosage forms such as liposomes, nanoparticles, nanocapsules, microspheres, microcapsules, microemulsions, and dendrimers has been studied to overcome the problems mentioned above. Dendrimers are a new class of polymeric materials. The unique nanostructured architecture of dendrimers has been studied to examine their role in delivery of therapeutics and imaging agents. Dendrimers can enhance drug's water solubility, bioavailability, and biocompatibility and can be applied for different routes of drug administration successfully. Permeability enhancer properties of dendrimers were also reported. The use of dendrimers can also reduce toxicity versus activity and following an appropriate application route they allow the delivery of the drug to the targeted site and provide desired pharmacokinetic parameters. Therefore, dendrimeric drug delivery systems are of interest in ocular drug delivery. In this review, the limitations related to eye's unique structure, the advantages of dendrimers, and the potential applications of dendrimeric systems to ophthalmology including imaging, drug, peptide, and gene delivery will be discussed. PMID:24396306
Full Text Available Various new technologies have been developed for the transdermal delivery of some important drugs. Transdermal route will always remain a lucrative area for drug delivery.The transdermal route of drug delivery has gained great interest of pharmaceutical research, as it circumvents number of problems associated with oral route of drug administration. The major barrier in transdermal delivery of drug is the skin intrinsic barrier, the stratum corneum, the outermost envelop of the skin that offers the principal hurdle for diffusion of hydrophilic ionisable bioactives. One of the very recent approaches is the use of ultradeformable carrier system (transfersomes®. Which is composed of phospholipid, surfactant, and water for enhanced transdermal delivery? The transfersomal system was much more efficient at delivering a low and high molecular weight drug to the skin in terms of quantity and depth. The system can be characterized by in vitro for vesicle shape and size, entrapment efficiency, degree of deformability, number of vesicles per cubic mm. Transferosome is an ultradeformable vesicle, elastic in nature which can squeeze itself through a pore which is many times smaller than its size owing to its elasticity. The uniqueness of this type of drug carrier system lies in the fact that it can accommodate hydrophilic, lipophilic as well as amphiphilic drugs. These drugs find place in different places in the elastic vesicle before they get delivered beneath the skin.
Rajera, Rampal; Nagpal, Kalpana; Singh, Shailendra Kumar; Mishra, Dina Nath
During the past decade formulation of vesicles as a tool to improve drug delivery, has created a lot of interest amongst the scientist working in the area of drug delivery systems. Vesicular system such as liposomes, niosomes, transferosomes, pharmacosomes and ethosomes provide an alternative to improve the drug delivery. Niosomes play an important role owing to their nonionic properties, in such drug delivery system. Design and development of novel drug delivery system (NDDS) has two prerequisites. First, it should deliver the drug in accordance with a predetermined rate and second it should release therapeutically effective amount of drug at the site of action. Conventional dosage forms are unable to meet these requisites. Niosomes are essentially non-ionic surfactant based multilamellar or unilamellar vesicles in which an aqueous solution of solute is entirely enclosed by a membrane resulting from the organization of surfactant macromolecules as bilayer. Niosomes are formed on hydration of non-ionic surfactant film which eventually hydrates imbibing or encapsulating the hydrating aqueous solution. The main aim of development of niosomes is to control the release of drug in a sustained way, modification of distribution profile of drug and for targeting the drug to the specific body site. This paper deals with composition, characterization/evaluation, merits, demerits and applications of niosomes. PMID:21719996
Janiffe Peres de Oliveira
Full Text Available The objective of this work was to characterize the biochemically systemic bacterial isolated from banana plants, to evaluate the bacterial sensitivity to antibiotics, and to determine the phytotoxicity of banana shoots during in vitro proliferation. Systemic bacteria belonging to the Klebsiella and Aeromonas genera were isolated from the “Maravilha” (FHIA 01 AAAB, “Preciosa” (PV 4285 AAAB and “Thap Maeo” (AAB varieties and were then characterized. Tests of shoot sensitivity to antibiotics were performed, and the minimum inhibitory concentration (MIC and phytotoxic effects of selected antibiotics to plants were determined. Among the 20 antibiotics evaluated, the strains showed sensitivity to cefaclor, cefalexin, cefalotin, nalidixic acid, chloramphenicol, and vancomycin. However, during MIC determination, the best results were obtained with cefaclor, vancomycin or nalidixic acid alone in concentrations ranging from 512 to 1,024 mg L-1. In culture medium, cefaclor at 1,024 mg L-1 was the only antibiotic to affect the multiplication and the shoot survival in culture.
Hwang, Sohyun; Kim, Chan Yeong; Ji, Sun-Gou; Go, Junhyeok; Kim, Hanhae; Yang, Sunmo; Kim, Hye Jin; Cho, Ara; Yoon, Sang Sun; Lee, Insuk
Pseudomonas aeruginosa is a Gram-negative bacterium of clinical significance. Although the genome of PAO1, a prototype strain of P. aeruginosa, has been extensively studied, approximately one-third of the functional genome remains unknown. With the emergence of antibiotic-resistant strains of P. aeruginosa, there is an urgent need to develop novel antibiotic and anti-virulence strategies, which may be facilitated by an approach that explores P. aeruginosa gene function in systems-level models. Here, we present a genome-wide functional network of P. aeruginosa genes, PseudomonasNet, which covers 98% of the coding genome, and a companion web server to generate functional hypotheses using various network-search algorithms. We demonstrate that PseudomonasNet-assisted predictions can effectively identify novel genes involved in virulence and antibiotic resistance. Moreover, an antibiotic-resistance network based on PseudomonasNet reveals that P. aeruginosa has common modular genetic organisations that confer increased or decreased resistance to diverse antibiotics, which accounts for the pervasiveness of cross-resistance across multiple drugs. The same network also suggests that P. aeruginosa has developed mechanism of trade-off in resistance across drugs by altering genetic interactions. Taken together, these results clearly demonstrate the usefulness of a genome-scale functional network to investigate pathogenic systems in P. aeruginosa.
Objective: Although evidence has already demonstrated that the performance of Health Delivery System (HDS) varies widely across nations, relatively little is known about the factors that give rise to these variations and the key point to improve the performance besides adjusting system structure. By setup of HDS performance measurement system on the base of association of financial, social, and environmental characteristics, we construct system dynamic model of HDS to simulate the invention policies. Methods:Performance measures were collected from HDS in 31 regions of China and combined with secondary data sources. Multivariate, linear, nonlinear regression and factor analysis models were used to estimate associations between system characteristics and the performance. Results: Performance varied significantly with the size, financial resources and organizational structure of HDS. Performance measurement system of health delivery system was developed to give the rank of all Chinese regions. Conclusion: Performance measurement system of HDS is the basic of HDS modeling by system dynamic.
Swalec, John J.
In the design and development of telecommunications-based instructional delivery systems, attention to faculty involvement and training is often overlooked until the system is operational. The Waubonsee Telecommunications Instructional Consortium (TIC), in Illinois, is one network that benefited from early faculty input. Even before the first…
VANDEWITTE, P; ESSELBRUGGE, H; PETERS, AMP; DIJKSTRA, PJ; FEIJEN, J; GROENEWEGEN, RJJ; SMID, J; OLIJSLAGER, J; SCHAKENRAAD, JM; EENINK, MJD; SAM, AP
Highly crystalline porous hollow poly (L-lactide) (PLLA) fibres suitable for the delivery of various drugs were obtained using a dry-wet spinning process. The pore structure of the fibres could be regulated by changing the spinning systems and spinning conditions. Using the spinning system PLLA-diox
Hetzel, C.; Janssen, R.; Ely, S.J.; Kristensen, N.M.; Bunting, K.; Cooper, J.B.; Lamb, J.R.; Young, D.B.; Thole, J.E.R.
We have developed a novel epitope delivery system based on the insertion of peptides within a permissive loop of a bacterial superoxide dismutase molecule. This system allowed high-level expression of heterologous peptides in two mycobacterial vaccine strains, Mycobacterium bovis bacille Calmette- G
Full Text Available Pharmaceutical invention and research are increasingly focusing on delivery systems which enhance desirable therapeutic objectives while minimising side effects. Recent trends indicate that multiparticulate drug delivery systems are especially suitable for achieving controlled or delayed release oral formulations with low risk of dose dumping, flexibility of blending to attain different release patterns as well as reproducible and short gastric residence time. Pelletization is a technique used to prepare fine powders into pellets used as multiparticulate drug delivery systems. There are different pelletization techniques used to prepare pellets. Extrusion and spheronization is one of them used to prepare pellets drug loaded beads/pellets for extended release or sustained release oral formulations such as tablets and capsules.
Devi, D Asha; Pavani, V L; Geethanjali, N
computers into the real world, to serve humans where the ubiquitous network is the underneath infrastructure. In order to provide ubiquitous services (u-Service) which deliver useful information to service users without human intervention, this paper implements a proactive information delivery system using Bluetooth technology. Bluetooth is a lowpowered networking service that supports several protocol profiles, most importantly file transfer.Combined together, ubiquitous computing and Bluetooth ha e the potential to furnish ubiquitous solutions (u-Solutions) that are efficient, employ simplified design characteristics, and collaboratively perform functions they are otherwise not capable. Thus, this paper first addresses the current Bluetooth technology. Then, it suggests and develops the proactive information delivery system utilizing Bluetooth and ubiquitous computing network concepts. The proactive information delivery system can be used in many ubiquitous applications such as ubiquitous commerce (u-Commer...
Zheng, Yi; Hu, Junqiang; Gao, Wenle
Electrohydrodynamic (EHD) generation, a commonly used method in BioMEMS, plays a significant role in the pulsatile drug delivery system for a decade. In this paper, an EHD based drug delivery system is well designed, which can be used to generate a single drug droplet as small as 2.83 nL in 8.5 ms with a total device of 2\\times2\\times3 mm^3, and an external supplied voltage of 1500 V. Theoretically, we derive the expressions for the size and the formation time of a droplet generated by EHD method, while taking into account the drug supply rate, properties of liquid, gap between two electrodes, nozzle size, and charged droplet neutralization. This work proves a repeatable, stable and controllable droplet generation and delivery system based on EHD method experimentally as well as theoretically.
Mathiowitz, Edith; Jacob, Jules S.; Jong, Yong S.; Carino, Gerardo P.; Chickering, Donald E.; Chaturvedi, Pravin; Santos, Camilla A.; Vijayaraghavan, Kavita; Montgomery, Sean; Bassett, Michael; Morrell, Craig
Biologically adhesive delivery systems offer important advantages1-5 over conventional drug delivery systems6. Here we show that engineered polymer microspheres made of biologically erodable polymers, which display strong adhesive interactions with gastrointestinal mucus and cellular linings, can traverse both the mucosal absorptive epithelium and the follicle-associated epithelium covering the lymphoid tissue of Peyer's patches. The polymers maintain contact with intestinal epithelium for extended periods of time and actually penetrate it, through and between cells. Thus, once loaded with compounds of pharmacological interest, the microspheres could be developed as delivery systems to transfer biologically active molecules to the circulation. We show that these microspheres increase the absorption of three model substances of widely different molecular size: dicumarol, insulin and plasmid DNA.
Adeltoft, Teresa Ajslev; Andersen, C S; Gamborg, M;
influencing the establishment and diversity of the gut microbiota are associated with later risk of overweight. Design: Longitudinal, prospective study with measure of exposures in infancy and follow-up at age 7 years. Methods: A total of 28¿354 mother–child dyads from the Danish National Birth Cohort.......54, 95% CI: 0.30–0.98). The same tendency was observed among children of obese mothers (OR: 0.85, 95% CI: 0.41–1.76). Conclusion: The present cohort study revealed that a combination of early exposures, including delivery mode, maternal pre-pregnancy BMI and antibiotics in infancy, influences the risk...... of overweight in later childhood. This effect may potentially be explained by an impact on establishment and diversity of the microbiota....
Shaikh, Mohsin; Choudhury, Namita Roy; Knott, Robert; Garg, Sanjay
Esophageal cancer patients are often diagnosed as "advanced" cases. These patients are subjected to palliative stenting using self-expanding metallic stents (SEMS) to maintain oral alimentation. Unfortunately, SEMS get reoccluded due to tumor growth, in and over the stent struts. To investigate potential solutions to this problem, docetaxel (DTX) delivery films were prepared using PurSil AL 20 (PUS), which can be used as a covering material for the SEMS. Drug-polymer miscibility and interactions were studied. Bilayer films were prepared by adhering the blank film to the DTX loaded film in order to maintain the unidirectional delivery to the esophagus. In vitro release and the local DTX delivery were studied using in vitro permeation experiments. It was found that DTX and PUS were physically and chemically compatible. The bilayer films exhibited sustained release (>30 days) and minimal DTX permeation through esophageal tissues in vitro. The rate-determining step for the DTX delivery was calculated. It was found that >0.9 fraction of rate control lies with the esophageal tissues, suggesting that DTX delivery can be sustained for longer periods compared to the in vitro release observed. Thus, the bilayer films can be developed as a localized sustained delivery system in combination with the stent. PMID:25936529
Shaikh, Mohsin; Choudhury, Namita Roy; Knott, Robert; Garg, Sanjay
Esophageal cancer patients are often diagnosed as "advanced" cases. These patients are subjected to palliative stenting using self-expanding metallic stents (SEMS) to maintain oral alimentation. Unfortunately, SEMS get reoccluded due to tumor growth, in and over the stent struts. To investigate potential solutions to this problem, docetaxel (DTX) delivery films were prepared using PurSil AL 20 (PUS), which can be used as a covering material for the SEMS. Drug-polymer miscibility and interactions were studied. Bilayer films were prepared by adhering the blank film to the DTX loaded film in order to maintain the unidirectional delivery to the esophagus. In vitro release and the local DTX delivery were studied using in vitro permeation experiments. It was found that DTX and PUS were physically and chemically compatible. The bilayer films exhibited sustained release (>30 days) and minimal DTX permeation through esophageal tissues in vitro. The rate-determining step for the DTX delivery was calculated. It was found that >0.9 fraction of rate control lies with the esophageal tissues, suggesting that DTX delivery can be sustained for longer periods compared to the in vitro release observed. Thus, the bilayer films can be developed as a localized sustained delivery system in combination with the stent.
Moodley, Kovanya; Pillay, Viness; Choonara, Yahya E; du Toit, Lisa C; Ndesendo, Valence M K; Kumar, Pradeep; Cooppan, Shivaan; Bawa, Priya
Recent pharmaceutical research has focused on controlled drug delivery having an advantage over conventional methods. Adequate controlled plasma drug levels, reduced side effects as well as improved patient compliance are some of the benefits that these systems may offer. Controlled delivery systems that can provide zero-order drug delivery have the potential for maximizing efficacy while minimizing dose frequency and toxicity. Thus, zero-order drug release is ideal in a large area of drug delivery which has therefore led to the development of various technologies with such drug release patterns. Systems such as multilayered tablets and other geometrically altered devices have been created to perform this function. One of the principles of multilayered tablets involves creating a constant surface area for release. Polymeric materials play an important role in the functioning of these systems. Technologies developed to date include among others: Geomatrix(®) multilayered tablets, which utilizes specific polymers that may act as barriers to control drug release; Procise(®), which has a core with an aperture that can be modified to achieve various types of drug release; core-in-cup tablets, where the core matrix is coated on one surface while the circumference forms a cup around it; donut-shaped devices, which possess a centrally-placed aperture hole and Dome Matrix(®) as well as "release modules assemblage", which can offer alternating drug release patterns. This review discusses the novel altered geometric system technologies that have been developed to provide controlled drug release, also focusing on polymers that have been employed in such developments. PMID:22312236
Drug delivery systems (DDS) using liposomes as drug carriers for targeting to macrophages have been developed for the treatment of diseases that macrophages are related to their progress. Initially, DDS for the treatment of atherosclerosis are described. The influence of particle size on the drug delivery to atherosclerotic lesions that macrophages are richly present and antiatherosclerotic effects following intravenous administration of liposomes containing dexamethasone (DXM-liposomes) was investigated in atherogenic mice. Both the drug delivery efficacy of DXM-liposomes (particle size, 200 nm) to atherosclerotic lesions and their antiatherosclerotic effects were greater than those of 70 and 500 nm. These results indicate that there is an optimal particle size for drug delivery to atherosclerotic lesions. DDS for the treatment of respiratory infections are then described. The influence of particle size and surface mannosylation on the drug delivery to alveolar macrophages (AMs) and antibacterial effects following pulmonary administration of liposomes containing ciprofloxacin (CPFX-liposomes) was investigated in rats. The drug delivery efficacy of CPFX-liposomes to AMs was particle size-dependent over the range 100-1000 nm and then became constant at over 1000 nm. These results indicate that the most effective size is 1000 nm. Both the drug delivery efficacy of mannosylated CPFX-liposomes (particle size, 1000 nm) to AMs and their antibacterial effects were significantly greater than those of unmodified CPFX-liposomes. These results indicate that the surface mannosylation is useful method for drug delivery to AMs. This review provides useful information to help in the development of novel pharmaceutical formulations aimed at drug targeting to macrophages.
Full Text Available Purpose: Treatment delivery monitoring is important for radiotherapy, which enables catching dosimetric error at the earliest possible opportunity. This project develops a virtual delivery system to monitor the dose delivery process of photon radiotherapy in real-time using GPU-based Monte Carlo (MC method.Methods: The simulation process consists of 3 parallel CPU threads. A thread T1 is responsible for communication with a linac, which acquires a set of linac status parameters, e.g. gantry angles, MLC configurations, and beam MUs every 20 ms. Since linac vendors currently do not offer interface to acquire data in real time, we mimic this process by fetching information from a linac dynalog file at the set frequency. Instantaneous beam fluence map (FM is calculated based. A FM buffer is also created in T1 and the instantaneous FM is accumulated to it. This process continues, until a ready signal is received from thread T2 on which an in-house developed MC dose engine executes on GPU. At that moment, the accumulated FM is transferred to T2 for dose calculations, and the FM buffer in T1 is cleared. Once the dose calculation finishes, the resulting 3D dose distribution is directed to thread T3, which displays it in three orthogonal planes in color wash overlaid on the CT image. This process continues to monitor the 3D dose distribution in real-time.Results: An IMRT and a VMAT cases used in our patient-specific QA are studied. Maximum dose differences between our system and treatment planning system are 0.98% and 1.58% for the IMRT and VMAT cases, respectively. The update frequency is >10Hz and the relative uncertainty level is 2%.Conclusion: By embedding a GPU-based MC code in a novel data/work flow, it is possible to achieve real-time MC dose calculations to monitor delivery process.------------------------------Cite this article as: Shi F, Gu X, Graves YJ, Jiang S, Jia X. A real-time virtual delivery system for photon radiotherapy delivery
Ling Xin Chen; Qing Ling Li; Xiao Lei Wang; Hai Long Wang; Ya Feng Guan
Nonmechanical pumping of liquids is of key importance for applications from the biomedical microfluidic chip to drug delivery systems. In this paper, a new electrokinetic pump (EOP) system with polycarbonate nanochannel membrane sandwiched between two membrane holders was constructed. The pump was tested with water and phosphate buffer at 1-6 V applied voltage, the maximum pressure and flow rate are 0.32 MPa (3.2 atm) and 4.2 μL/min for phosphate buffer, respectively. This proof-of-concept pump shows its potential use for drugs or chemical agents delivery by the usage of different membrane materials.
Dhote, Vinod; Bhatnagar, Punit; Pradyumna K Mishra; Mahajan, Suresh C.; Mishra, Dinesh K.
The delivery of drugs into systemic circulation via skin has generated much attention during the last decade. Transdermal therapeutic systems propound controlled release of active ingredients through the skin and into the systemic circulation in a predictive manner. Drugs administered through these systems escape first-pass metabolism and maintain a steady state scenario similar to a continuous intravenous infusion for up to several days. However, the excellent impervious nature of the skin o...
The increasing number of lipophilic drug candidates in development in the pharmaceutical industry calls for advanced drug delivery systems with increased bioavailability less day-to-day and food-intake-dependent. Many of these drug candidates possess poor water solubility, so that their dissolution rate in the gastrointestinal tract (GIT) limits their absorption following oral administration. In the past few decades, various lipid-based formulations have been investigated to enhance the bi...
Chudasama, A. S.; Patel, V. V.; Nivsarkar, M.; Kamala K Vasu; C. J. Shishoo
Nevirapine is a highly lipophilic and water insoluble non-nucleoside reverse transcriptase inhibitor used for the treatment of HIV-1 infection. Lymphoid tissue constitutes the major reservoir of HIV virus and infected cells in HIV-infected patients. Self-emulsifying drug delivery system, using long chain triglycerides, is a popular carrier of drugs due to their ability to transport lipophilic drugs into the lymphatic circulation. However, HIV/AIDS patients experience a variety of functional a...
Maity, Amit Ranjan; Stepensky, David
Many drugs have been designed to act on intracellular targets and to affect intracellular processes inside target cells. For the desired effects to be exerted, these drugs should permeate target cells and reach specific intracellular organelles. This subcellular drug targeting approach has been proposed for enhancement of accumulation of these drugs in target organelles and improved efficiency. This approach is based on drug encapsulation in drug delivery systems (DDSs) and/or their decoration with specific targeting moieties that are intended to enhance the drug/DDS accumulation in the intracellular organelle of interest. During recent years, there has been a constant increase in interest in DDSs targeted to specific intracellular organelles, and many different approaches have been proposed for attaining efficient drug delivery to specific organelles of interest. However, it appears that in many studies insufficient efforts have been devoted to quantitative analysis of the major formulation parameters of the DDSs disposition (efficiency of DDS endocytosis and endosomal escape, intracellular trafficking, and efficiency of DDS delivery to the target organelle) and of the resulting pharmacological effects. Thus, in many cases, claims regarding efficient delivery of drug/DDS to a specific organelle and efficient subcellular targeting appear to be exaggerated. On the basis of the available experimental data, it appears that drugs/DDS decoration with specific targeting residues can affect their intracellular fate and result in preferential drug accumulation within an organelle of interest. However, it is not clear whether these approaches will be efficient in in vivo settings and be translated into preclinical and clinical applications. Studies that quantitatively assess the mechanisms, barriers, and efficiencies of subcellular drug delivery and of the associated toxic effects are required to determine the therapeutic potential of subcellular DDS targeting.
Full Text Available Pulsatile drug delivery systems are gaining popularity in the field of pharmaceutical formulation, research and development. The prime advantage in this drug delivery is that the drug is released as per the pathophysiological need of the disease. As a result the change of development of drug resistance which is seen in conventional and sustained released formulations can be reduced. This therapy is mainly applicable where sustained action is not required and the drugs are toxic. Basic point of development of this formulation is to find out the circadian rhythms that is a suitable indicator that will trigger the release of drug from the device. Clock genes are the genes that control the circadian rhythms in human physiology. Pulsatile drug delivery systems are promising incase of asthma, cardiovascular diseases, peptic ulcers, arthritis, and hypercholesterolemic conditions.
Full Text Available To identify key regulators of subminimum inhibitory concentration (sub-MIC antibiotic response in the Pasteurella multocida proteome, we applied systems approaches. Using 2D-LC-ESI-MS2, we achieved 53% proteome coverage. To study the differential protein expression in response to sub-MIC antibiotics in the context of protein interaction networks, we inferred P. multocida Pm70 protein interaction network from orthologous proteins. We then overlaid the differential protein expression data onto the P. multocida protein interaction network to study the bacterial response. We identified proteins that could enhance antimicrobial activity. Overall compensatory response to antibiotics was characterized by altered expression of proteins involved in purine metabolism, stress response, and cell envelope permeability.
Liu, Lei; Tang, Yonghong; Dai, Sheng; Kleitz, Freddy; Qiao, Shi Zhang
A novel smart nanoparticle-based system has been developed for tracking intracellular drug delivery through surface-enhanced Raman scattering (SERS). This new drug delivery system (DDS) shows targeted cytotoxicity towards cancer cells via pH-cleavable covalent carboxylic hydrazone links and the SERS tracing capability based on gold@silica nanocarriers. Doxorubicin, as a model anticancer drug, was employed to compare SERS with conventional fluorescence tracing approaches. It is evident that SERS demonstrates higher sensitivity and resolution, revealing intracellular details, as the strengths of the original Raman signals can be amplified by SERS. Importantly, non-destructive SERS will provide the designed DDS with great autonomy and potential to study the dynamic procedures of non-fluorescent drug delivery into living cells.A novel smart nanoparticle-based system has been developed for tracking intracellular drug delivery through surface-enhanced Raman scattering (SERS). This new drug delivery system (DDS) shows targeted cytotoxicity towards cancer cells via pH-cleavable covalent carboxylic hydrazone links and the SERS tracing capability based on gold@silica nanocarriers. Doxorubicin, as a model anticancer drug, was employed to compare SERS with conventional fluorescence tracing approaches. It is evident that SERS demonstrates higher sensitivity and resolution, revealing intracellular details, as the strengths of the original Raman signals can be amplified by SERS. Importantly, non-destructive SERS will provide the designed DDS with great autonomy and potential to study the dynamic procedures of non-fluorescent drug delivery into living cells. Electronic supplementary information (ESI) available. See DOI: 10.1039/c6nr03869g
J.M.A. Daniels; D. Snijders; C.S. de Graaff; F. Vlaspolder; H.M. Jansen; W.G. Boersma
Rationale: The role of antibiotics in acute exacerbations is controversial and their efficacy when added to systemic corticosteroids is unknown. Objectives: We conducted a randomized, placebo-controlled trial to determine the effects of doxycycline in addition to corticosteroids on clinical outcome,
Rajan, Reshmy; Jose, Shoma; Mukund, V P Biju; Vasudevan, Deepa T
Transdermal administration of drugs is generally limited by the barrier function of the skin. Vesicular systems are one of the most controversial methods for transdermal delivery of active substances. The interest in designing transdermal delivery systems was relaunched after the discovery of elastic vesicles like transferosomes, ethosomes, cubosomes, phytosomes, etc. This paper presents the composition, mechanisms of penetration, manufacturing and characterization methods of transferosomes as transdermal delivery systems of active substances. For a drug to be absorbed and distributed into organs and tissues and eliminated from the body, it must pass through one or more biological membranes/barriers at various locations. Such a movement of drug across the membrane is called as drug transport. For the drugs to be delivered to the body, they should cross the membranous barrier. The concept of these delivery systems was designed in an attempt to concentrate the drug in the tissues of interest, while reducing the amount of drug in the remaining tissues. Hence, surrounding tissues are not affected by the drug. In addition, loss of drug does not happen due to localization of drug, leading to get maximum efficacy of the medication. Therefore, the phospholipid based carrier systems are of considerable interest in this era. PMID:22171309
Full Text Available Transdermal administration of drugs is generally limited by the barrier function of the skin. Vesicular systems are one of the most controversial methods for transdermal delivery of active substances. The interest in designing transdermal delivery systems was relaunched after the discovery of elastic vesicles like transferosomes, ethosomes, cubosomes, phytosomes, etc. This paper presents the composition, mechanisms of penetration, manufacturing and characterization methods of transferosomes as transdermal delivery systems of active substances. For a drug to be absorbed and distributed into organs and tissues and eliminated from the body, it must pass through one or more biological membranes/barriers at various locations. Such a movement of drug across the membrane is called as drug transport. For the drugs to be delivered to the body, they should cross the membranous barrier. The concept of these delivery systems was designed in an attempt to concentrate the drug in the tissues of interest, while reducing the amount of drug in the remaining tissues. Hence, surrounding tissues are not affected by the drug. In addition, loss of drug does not happen due to localization of drug, leading to get maximum efficacy of the medication. Therefore, the phospholipid based carrier systems are of considerable interest in this era.
Rajan, Reshmy; Jose, Shoma; Mukund, V. P. Biju; Vasudevan, Deepa T.
Transdermal administration of drugs is generally limited by the barrier function of the skin. Vesicular systems are one of the most controversial methods for transdermal delivery of active substances. The interest in designing transdermal delivery systems was relaunched after the discovery of elastic vesicles like transferosomes, ethosomes, cubosomes, phytosomes, etc. This paper presents the composition, mechanisms of penetration, manufacturing and characterization methods of transferosomes as transdermal delivery systems of active substances. For a drug to be absorbed and distributed into organs and tissues and eliminated from the body, it must pass through one or more biological membranes/barriers at various locations. Such a movement of drug across the membrane is called as drug transport. For the drugs to be delivered to the body, they should cross the membranous barrier. The concept of these delivery systems was designed in an attempt to concentrate the drug in the tissues of interest, while reducing the amount of drug in the remaining tissues. Hence, surrounding tissues are not affected by the drug. In addition, loss of drug does not happen due to localization of drug, leading to get maximum efficacy of the medication. Therefore, the phospholipid based carrier systems are of considerable interest in this era. PMID:22171309
Full Text Available Haifa Al-Dubai1, Gisela Pittner1, Fritz Pittner1, Franz Gabor21Max F Perutz Laboratories, Department of Biochemistry, University of Vienna, Vienna, Austria; 2Department of Pharmaceutical Technology and Biopharmaceutics, Faculty of Life Sciences, University of Vienna, Vienna, AustriaAbstract: Feasibility studies have been carried out for development of a biocompatible coating of medical implant materials allowing the binding of biodegradable drug-delivery systems in a way that their reloading might be possible. These novel coatings, able to bind biodegradable nanoparticles, may serve in the long run as drug carriers to mediate local pharmacological activity. After biodegradation of the nanoparticles, the binding sites could be reloaded with fresh drug-delivering particles. As a suitable receptor system for the nanoparticles, antibodies are anchored. The design of the receptor is of great importance as any bio- or chemorecognitive interaction with other components circulating in the blood has to be avoided. Furthermore, the binding between receptor and the particles has to be strong enough to keep them tightly bound during their lifetime, but on the other hand allow reloading after final degradation of the particles. The nanoparticles suggested as a drug-delivery system for medical implants can be loaded with different pharmaceuticals such as antibiotics, growth factors, or immunosuppressives. This concept may enable the changing of medication, even after implantation of the medical device, if afforded by patients’ needs.Keywords: antibody immobilization, biocompatible coating, chitosan nanoparticles, drug targeting, medical device
Felipe Rebello Lourenço
Full Text Available The aim of this study was to determine the optimal experimental conditions to develop a methodology for microbiological assay of apramycin employing microplate and kinetic reading mode, and to validate the developed method, through evaluation of parameters of selectivity, linearity, linear range, limits of detection and quantification, accuracy and precision. The turbidimetric assay principle is simple: the test solution is added to a suspension of test microorganism in culture media, the mixture is incubated under appropriate conditions and the microbial growth is measured by photometric reading. Microplate with kinetic reading mode employed in antibiotic assay is of considerable interest since it allows reduction of material and analysis time and enables a large number of samples to be analyzed simultaneously, with automated reading and calculating. Established conditions considered the standard-curve of apramycin at concentrations from 5.0 to 35.0 μg mL-1, and tryptic soy broth inoculated with 5% Escherichia coli (ATCC 8739 suspension. Satisfactory results were obtained with 2 hours of incubation. The developed method showed appropriate selectivity, linearity in the range from 5.0 to 35.0 μg mL-1, limits of detection and quantification of 0.1 and 0.4 μg mL-1, respectively, as well as satisfactory accuracy (recuperation = 98.5% and precision (RSD = 6.0%. Microplate assay combined the characteristics of microbiological (evaluation of antibiotic activity against sensitive test microorganism and physico-chemical (operationally straightforward and faster results assays.O objetivo deste trabalho é determinar as condições experimentais ideais para o desenvolvimento de metodologia para a dosagem microbiológica de apramicina empregando microplacas e modo de leitura cinético e validar o método desenvolvido, através da avaliação dos parâmetros de especificidade e seletividade, linearidade, faixa ou intervalo linear, limite de detecção e
Klunder; ,Edgar B.
The invention presents a device for the removal of elemental mercury from flue gas streams utilizing a layer of activated carbon particles contained within the filter fabric of a filter bag for use in a flue gas scrubbing system.
Full Text Available Martino Maria Zacchè, Sushma Srikrishna, Linda Cardozo Department of Urogynaecology, King's College Hospital, London, UK Abstract: The objective of pharmaceutics is the development of drugs with increased efficacy and reduced side effects. Prolonged exposure of the diseased tissue to the drug is of crucial importance. Drug-delivery systems (DDSs have been introduced to control rate, time, and place of release. Drugs can easily reach the bladder through a catheter, while systemically administered agents may undergo extensive metabolism. Continuous urine filling and subsequent washout hinder intravesical drug delivery (IDD. Moreover, the low permeability of the urothelium, also described as the bladder permeability barrier, poses a major challenge in the development of the IDD. DDSs increase bioavailability of drugs, therefore improving therapeutic effect and patient compliance. This review focuses on novel DDSs to treat bladder conditions such as overactive bladder, interstitial cystitis, bladder cancer, and recurrent urinary tract infections. The rationale and strategies for both systemic and local delivery methods are discussed, with emphasis on new formulations of well-known drugs (oxybutynin, nanocarriers, polymeric hydrogels, intravesical devices, encapsulated DDSs, and gene therapy. We give an overview of current and future prospects of DDSs for bladder disorders, including nanotechnology and gene therapy. Keywords: drug targeting, drug-delivery system, bladder disorders
Juliana De Souza Rebouças
Full Text Available In the last decades, significant progress in research and clinics has been made to offer possible innovative therapeutics for the management of allergic diseases. However, current allergen immunotherapy shows limitations concerning the long-term efficacy and safety due to local side effects and risk of anaphylaxis. Thus, effective and safe vaccines with reduced dose of allergen have been developed using adjuvants. Nevertheless, the use of adjuvants still has several disadvantages, which limits its use in human vaccines. In this context, several novel adjuvants for allergen immunotherapy are currently being investigated and developed. Currently, nanoparticles-based allergen-delivery systems have received much interest as potential adjuvants for allergen immunotherapy. It has been demonstrated that the incorporation of allergens into a delivery system plays an important role in the efficacy of allergy vaccines. Several nanoparticles-based delivery systems have been described, including biodegradable and nondegradable polymeric carriers. Therefore, this paper provides an overview of the current adjuvants used for allergen immunotherapy. Furthermore, nanoparticles-based allergen-delivery systems are focused as a novel and promising strategy for allergy vaccines.
Kolakovic, Ruzica; Viitala, Tapani; Ihalainen, Petri;
INTRODUCTION: There has been increased activity in the field recently regarding the development and research on various printing techniques in fabrication of dosage forms and drug delivery systems. These technologies may offer benefits and flexibility in manufacturing, potentially paving the way...... for personalized dosing and tailor-made dosage forms.\
Stephansen, Karen; Chronakis, Ioannis S.; Jessen, Flemming
fiberswere insoluble in water. However, when exposed to proteolytic enzymes, the fibers were degraded. Thedegradation products of the FSP fibers proved to be inhibitors of the diabetes-related enzyme DPP-IV. TheFSP fibers may have biomedical applications, among others as a delivery system. To demonstrate...
De Souza Rebouças, Juliana; Esparza, Irene; Ferrer, Marta; Sanz, María Luisa; Irache, Juan Manuel; Gamazo, Carlos
In the last decades, significant progress in research and clinics has been made to offer possible innovative therapeutics for the management of allergic diseases. However, current allergen immunotherapy shows limitations concerning the long-term efficacy and safety due to local side effects and risk of anaphylaxis. Thus, effective and safe vaccines with reduced dose of allergen have been developed using adjuvants. Nevertheless, the use of adjuvants still has several disadvantages, which limits its use in human vaccines. In this context, several novel adjuvants for allergen immunotherapy are currently being investigated and developed. Currently, nanoparticles-based allergen-delivery systems have received much interest as potential adjuvants for allergen immunotherapy. It has been demonstrated that the incorporation of allergens into a delivery system plays an important role in the efficacy of allergy vaccines. Several nanoparticles-based delivery systems have been described, including biodegradable and nondegradable polymeric carriers. Therefore, this paper provides an overview of the current adjuvants used for allergen immunotherapy. Furthermore, nanoparticles-based allergen-delivery systems are focused as a novel and promising strategy for allergy vaccines.
Full Text Available Magnetic microspheres hold great promise for reaching the goal of controlled and site specific drug delivery. Magnetic microspheres as an alternative to traditional radiation methods which uses highly penetrating radiations that is absorbed throughout the body. Its use is limited by toxicity and side effects. Now days, several targeted treatment systems including magnetic field, electric field, ultrasound, temperature, UV light and mechanical force are being used in many disease treatments (e.g. cancer, nerve damage, heart and artery, anti-diabetic, eye and other medical treatments. Among them, the magnetic targeted drug delivery system is one of the most attractive and promising strategy for delivering the drug to the specified site. Magnetically controlled drug targeting is one of the various possible ways of drug targeting. This technology is based on binding establish anticancer drug with ferrofluid that concentrate the drug in the area of interest (tumor site by means of magnetic fields. There has been keen interest in the development of a magnetically target drug delivery system. These drug delivery systems aim to deliver the drug at a rate directed by the needs of the body during the period of treatment, and target the activity entity to the site of action. Magnetic microspheres were developed to overcome two major problems encountered in drug targeting namely: RES clearance and target site specificity.
Gao, Yuan; Wang, Jingkang; Wang, Yongli; Yin, Qiuxiang; Glennon, Brian; Zhong, Jian; Ouyang, Jinbo; Huang, Xin; Hao, Hongxun
Low water solubility of drug products causes delivery problems such as low bioavailability. The reduced particle size and increased surface area of nanocrystals lead to the increasing of the dissolution rate. The formulation of drug nanocrystals is a robust approach and has been widely applied to drug delivery system (DDS) due to the significant development of nanoscience and nanotechnology. It can be used to improve drug efficacy, provide targeted delivery and minimize side-effects. Crystallization is the main and efficient unit operation to produce nanocrystals. Both traditional crystallization methods such as reactive crystallization, anti-solvent crystallization and new crystallization methods such as supercritical fluid crystallization, high-gravity controlled precipitation can be used to produce nanocrystals. The current mini-review outlines the main crystallization methods addressed in literature. The advantages and disadvantages of each method were summarized and compared.
Wang, Cong; Mazur, Paul; Cosse, Julia; Rider, Stephanie; Gharib, Morteza
Micro-needle injections, a promising pain-free drug delivery method, is constrained by its limited penetration depth. This deficiency can be overcome by implementing fast unsteady jet that can penetrate sub-dermally. The development of a faster liquid jet would increase the penetration depth and delivery volume of micro-needles. In this preliminary work, the nonlinear transient behavior of an elastic tube balloon in providing fast discharge is analyzed. A physical model that combines the Mooney Rivlin Material model and Young-Lapalce's Law was developed and used to investigate the fast discharging dynamic phenomenon. A proof of concept prototype was constructed to demonstrate the feasibility of a simple thumb-sized delivery system to generate liquid jet with desired speed in the range of 5-10 m/s. This work is supported by ZCUBE Corporation.
Chow, Angela L. P.; Lye, David C.; Arah, Onyebuchi A.
Antibiotic computerised decision support systems (CDSSs) are shown to improve antibiotic prescribing, but evidence of beneficial patient outcomes is limited. We conducted a prospective cohort study in a 1500-bed tertiary-care hospital in Singapore, to evaluate the effectiveness of the hospital’s antibiotic CDSS on patients’ clinical outcomes, and the modification of these effects by patient factors. To account for clustering, we used multilevel logistic regression models. One-quarter of 1886 eligible inpatients received CDSS-recommended antibiotics. Receipt of antibiotics according to CDSS’s recommendations seemed to halve mortality risk of patients (OR 0.54, 95% CI 0.26-1.10, P = 0.09). Patients aged ≤65 years had greater mortality benefit (OR 0.45, 95% CI 0.20-1.00, P = 0.05) than patients that were older than 65 (OR 1.28, 95% CI 0.91-1.82, P = 0.16). No effect was observed on incidence of Clostridium difficile (OR 1.02, 95% CI 0.34-3.01), and multidrug-resistant organism (OR 1.06, 95% CI 0.42-2.71) infections. No increase in infection-related readmission (OR 1.16, 95% CI 0.48-2.79) was found in survivors. Receipt of CDSS-recommended antibiotics reduced mortality risk in patients aged 65 years or younger and did not increase the risk in older patients. Physicians should be informed of the benefits to increase their acceptance of CDSS recommendations.
Omnia Sarhan, Mahmoud M. Ibrahim* and Mahmoud Mahdy
Full Text Available Glibenclamide is practically insoluble in water and its gastrointestinal absorption is limited by its dissolution rate. Therefore, to enhance the drug dissolution and its hypoglycemic effects, the drug was formulated in different microemulsion systems and in vitro/in vivo evaluated. Microemulsion systems were prepared by Water titration method in which surfactants and cosurfactants (S/CoS were mixed at different weight ratios of 1:1, 2:1 and 3:1. They were subjected to transmission electron microscopical examination, pH determination and viscosity tests. The solubility of Glibenclamide in different microemulsion systems was determined. Forms 8, 9, 10, 11, 14 and 18 were found to have high Glibenclamide solubility using different oils. Form 11 and 9 showed the highest Glibenclamide release rates of 59.72% and 52.35%, respectively after 6 hours. In-vivo studies were tested using diabetic rats by application of form 11 with n-butanol as cosurfactant transdermally and form 8 with propylene glycol cosurfactant orally and transdermally. The results were compared to the drug suspension as a positive control. It was shown that microemulsion systems gave an effective tool of increasing drug dissolution probably due to enhanced wettability and reduced drug particle size, which in turn led to enhance its hypoglycemic effects.
Full Text Available Jun Wu,1 Yi Zuo,2 Yunjiu Hu,1 Jian Wang,2 Jidong Li,2 Bo Qiao,1 Dianming Jiang1 ¹Department of Orthopedics, The First Affiliated Hospital of Chongqing Medical University, Chongqing, People’s Republic of China; ²Research Center for Nano-Biomaterials, Analytical and Testing Center, Sichuan University, Chengdu, Sichuan, People’s Republic of China Abstract: The study was to develop and evaluate the rifapentine-loaded poly(lactic acid-co-glycolic acid (PLGA microspheres (RPMs for the treatment of osteoarticular tuberculosis to avoid critical side effects caused by oral regimens of antibiotics or intravenous antibiotics. The RPMs were spherical with rough surfaces, and elevated amounts of rifapentine in the formulation markedly increased the particle size and drug loading, while decreased the size distribution and entrapment efficiency. The highest drug loading and encapsulation efficiency of RPMs were 23.93%±3.93% and 88.49%±8.49%, respectively. After the initial rapid drug release, the release rate gradually decreased, and approximately 80% of the encapsulated rifapentine was released after 30 days of incubation. Moreover, RPMs could effectively inhibit the growth of Staphylococcus aureus. With increasing rifapentine content, the inhibition zones were continuously enlarged while the minimal inhibitory concentration values decreased. These results suggested that RPMs were bioactive and controlled release delivery systems for the treatment of osteoarticular tuberculosis. Keywords: Staphylococcus aureus, antitubercular drugs, in vitro, PLGA microspheres, chemotherapy, antibacterial
Bedder, M D; Burchiel, K; Larson, A
This survey compares costs of two commonly utilized implantable narcotic delivery systems. The systems are classified into type-I (exteriorized system using the DuPen epidural catheter) and type-II (implanted system using the Synchromed pump). Costs were analyzed by reviewing actual patient hospital financial service records and Homecare vendor quotations. From the perspective of cost analysis alone, we conclude that savings accrue when patients requiring treatment beyond 3 months duration are managed with a type-II implanted system compared with a type-I system with an external pump. PMID:1908884
Chouhan, Neeraj; Mittal, Vineet; Kaushik, Deepak; Khatkar, Anurag; Raina, Mitali
The self emulsifying drug delivery system (SEDDS) is considered to be the novel technique for the delivery of lipophillic plant actives. The self emulsifying (SE) formulation significantly enhance the solubility and bioavailability of poorly aqueous soluble phytoconstituents. The self emulsifying drug delivery system (SEDDS) can be developed for such plant actives to enhance the oral bioavailability using different excipients (lipid, surfactant, co solvent etc.) and their concentration is selected on the basis of pre formulation studies like phase equilibrium studies, solvent capacity of oil for drug and mutual miscibility of excipients. The present review focuses mainly on the development of SEDDS and effect of excipients on oral bioavailability and aqueous solubility of poorly water soluble phytoconstituents/ derived products. A recent list of patents issued for self emulsifying herbal formulation has also been included. The research data for various self emulsifying herbal formulation and patents issued were reviewed using different databases such as PubMed, Google Scholar, Google patents, Scopus and Web of Science. In a nutshell, we can say that SEDDS was established as a novel drug delivery system for herbals and with the advances in this technique, lots of patents on herbal SEDDS can be translated into the commercial products. PMID:25335929
Ranghar, Shweta; Sirohi, Parul [Department of Applied Mechanics, Motilal Nehru National Institute of Technology, Allahabad (India); Verma, Pritam; Agarwal, Vishnu, E-mail: email@example.com [Department of Biotechnology, Motilal Nehru National Institute of Technology, Allahabad (India)
Despite the fact that many new drugs and technologies have been developed to combat the infectious diseases, these have continued to be global health challenges. The use of conventional antimicrobial agents against these infections is always associated with problems such as the development of multiple drug resistance and adverse side effects. In addition, the inefficient traditional drug delivery system results in inadequate therapeutic index, low bioavailability of drugs and many other limitations. In this regard, antimicrobial nanoparticles and nanosized drug delivery carriers have emerged as potent effective agents against the infections. Nanoparticles have unique properties owing to their ultra small and controllable size such as high surface area, enhanced reactivity, and functionalizable structure. This review focused on different classes of antimicrobial nanoparticles, including metal, metal oxide and others along with their mechanism of action and their potential use against the infections. The review also focused on the development of nanoparticle systems for antimicrobial drug delivery and use of these systems for delivery of various antimicrobial agents, giving an overview about modern nanoparticle based therapeutic strategies against the infections. (author)
Kashyap, Prem Lal; Xiang, Xu; Heiden, Patricia
Development of technologies that improve food productivity without any adverse impact on the ecosystem is the need of hour. In this context, development of controlled delivery systems for slow and sustained release of agrochemicals or genetic materials is crucial. Chitosan has emerged as a valuable carrier for controlled delivery of agrochemicals and genetic materials because of its proven biocompatibility, biodegradability, non-toxicity, and adsorption abilities. The major advantages of encapsulating agrochemicals and genetic material in a chitosan matrix include its ability to function as a protective reservoir for the active ingredients, protecting the ingredients from the surrounding environment while they are in the chitosan domain, and then controlling their release, allowing them to serve as efficient gene delivery systems for plant transformation or controlled release of pesticides. Despite the great progress in the use of chitosan in the area of medical and pharmaceutical sciences, there is still a wide knowledge gap regarding the potential application of chitosan for encapsulation of active ingredients in agriculture. Hence, the present article describes the current status of chitosan nanoparticle-based delivery systems in agriculture, and to highlight challenges that need to be overcome.
Full Text Available Polymers have always been valuable excipients in conventional dosage forms, also have shown excellent performance into the parenteral arena, and are now capable of offering advanced and sophisticated functions such as controlled drug release and drug targeting. Advances in polymer science have led to the development of several novel drug delivery systems. Interpenetrating polymer networks (IPNs have shown superior performances over the conventional individual polymers and, consequently, the ranges of applications have grown rapidly for such class of materials. The advanced properties of IPNs like swelling capacity, stability, biocompatibility, nontoxicity and biodegradability have attracted considerable attention in pharmaceutical field especially in delivering bioactive molecules to the target site. In the past few years various research reports on the IPN based delivery systems showed that these carriers have emerged as a novel carrier in controlled drug delivery. The present review encompasses IPNs, their types, method of synthesis, factors which affects the morphology of IPNs, extensively studied IPN based drug delivery systems, and some natural polymers widely used for IPNs.
Zhang, Di; Garces, Luis Jose; Dai, Jian; Lai, Rixin
A power transmission system includes a first unit for carrying out the steps of receiving high voltage direct current (HVDC) power from an HVDC power line, generating an alternating current (AC) component indicative of a status of the first unit, and adding the AC component to the HVDC power line. Further, the power transmission system includes a second unit for carrying out the steps of generating a direct current (DC) voltage to transfer the HVDC power on the HVDC power line, wherein the HVDC power line is coupled between the first unit and the second unit, detecting a presence or an absence of the added AC component in the HVDC power line, and determining the status of the first unit based on the added AC component.
Cho, Hea-Young; Choi, Ji-Hoon; Oh, In-Joon; Lee, Yong-Bok
A self-emulsifying drug delivery system (SEDDS) containing tacrolimus has been developed to enhance the bioavailability and lymphatic delivery of tacrolimus. Solubility tests, combination tests, and phase diagrams were constructed for different sorts and ratios of oils, surfactants, and cosurfactants to identify optimal formulation. Optimized SEDDS was assessed for droplet size, zeta potential, stability in various media, and in vitro release. The tacrolimus-loaded SEDDS and commercial capsule (Prograf®) were orally administered (5 mg/kg) to rats. Whole blood, and mesenteric and axillary lymph node samples were taken and the concentrations of tacrolimus were measured to evaluate pharmacokinetic characteristics and the lymphatic delivery effects. The optimized SEDDS droplets were approximately 40 nm in size and stable enough to endure gastric pH environments. The release rate of tacrolimus from SEDDS was significantly higher than that from the commercial capsule. The bioavailability of tacrolimus in SEDDS after oral administration was significantly improved versus that of Prograf®. The lymphatic targeting efficiency of the prepared SEDDS formulation showed significantly greater than that of Prograf®. Our research indicates that prepared SEDDS can be an alternative to the conventional oral formulation of tacrolimus. Furthermore, SEDDS should be explored as a potential drug carrier for other lipophilic drugs. PMID:26353739
Gruenberg, Leonard; Wallack, Stanley S.; Tompkins, Christopher P.
This article discusses alternative methods for establishing a fairer pricing mechanism for Medicare recipients who enroll in health maintenance organizations and other competitive medical plans. The current method, based upon the adjusted average per capita cost, is inadequate because it fails to adjust premium levels for differences in health status; it establishes undesirable incentives that may lead to underservice, and it is tied to costs in the fee-for-service system. Alternative methods...
Matias J. Cardoso; Costa, Rui R.; Mano, João F.
Oceans are a vast source of natural substances. In them, we find various compounds with wide biotechnological and biomedical applicabilities. The exploitation of the sea as a renewable source of biocompounds can have a positive impact on the development of new systems and devices for biomedical applications. Marine polysaccharides are among the most abundant materials in the seas, which contributes to a decrease of the extraction costs, besides their solubility behavior in aqueous solvents an...
Caroline Moura Martins Lobo Santos
Full Text Available To evaluate the effects of systemic antibiotics in combination with scaling and root planing (SRP on periodontal parameters, tooth loss and oral health-related quality of life in diabetes patients.Two independent reviewers screened for controlled clinical trials with at least 6-month follow-up in six electronic databases, registers of clinical trials, meeting abstracts and four major dental journals. After duplicates removal, electronic and hand searches yielded 1,878 records; 18 full-text articles were independently read by two reviewers. To evaluate the additional effect of antibiotic usage, pooled weighted mean differences and 95% confidence intervals were calculated using a fixed effects model.Five studies met the inclusion criteria, four of which were included in meta-analyses. The meta-analyses showed a significant effect favouring SRP plus antibiotic for reductions in mean probing depth (PD (-0.22 mm [-0.34, -0.11] and mean percentage of bleeding on probing (BoP (4% [-7, -1]. There was no significant effect for clinical attachment level gain and plaque index reduction. No study reported on tooth loss and oral health-related quality of life.Adjunctive systemic antibiotic use in diabetic patients provides a small additional benefit in terms of reductions in mean PD and mean percentage of BoP.CRD42013006389.
Santos, Caroline Moura Martins Lobo; Lira-Junior, Ronaldo; Fischer, Ricardo Guimarães; Santos, Ana Paula Pires; Oliveira, Branca Heloisa
Aim To evaluate the effects of systemic antibiotics in combination with scaling and root planing (SRP) on periodontal parameters, tooth loss and oral health-related quality of life in diabetes patients. Materials and Methods Two independent reviewers screened for controlled clinical trials with at least 6-month follow-up in six electronic databases, registers of clinical trials, meeting abstracts and four major dental journals. After duplicates removal, electronic and hand searches yielded 1,878 records; 18 full-text articles were independently read by two reviewers. To evaluate the additional effect of antibiotic usage, pooled weighted mean differences and 95% confidence intervals were calculated using a fixed effects model. Results Five studies met the inclusion criteria, four of which were included in meta-analyses. The meta-analyses showed a significant effect favouring SRP plus antibiotic for reductions in mean probing depth (PD) (-0.22 mm [-0.34, -0.11]) and mean percentage of bleeding on probing (BoP) (4% [-7, -1]). There was no significant effect for clinical attachment level gain and plaque index reduction. No study reported on tooth loss and oral health-related quality of life. Conclusion Adjunctive systemic antibiotic use in diabetic patients provides a small additional benefit in terms of reductions in mean PD and mean percentage of BoP. Registration PROSPERO: CRD42013006389. PMID:26693909
Verdugo, Fernando; Laksmana, Theresia; Uribarri, Agurne
Peri-implantitis has emerged in the last few years as a complication difficult to resolve. The etiopathogenesis consensus is mainly attributed to bacteria. Following the preferred reporting items for systematic reviews and meta-analysis (PRISMA) guidelines, a PubMed/Medline literature search was performed using the US National Library of Medicine database up to 2015 to analyze available scientific data on the rationale and risk of superinfection associated to systemic antimicrobials in human peri-implant disease. A hand search was also conducted on relevant medical and microbiology journals. The methodological index for non-randomized studies (MINORS) was independently assessed for quality on the selected papers. Proposed combined therapies use broad-spectrum antibiotics to halt the disease progression. A major associated risk, particularly when prescribed empirically without microbiological follow-up, is the undetected development of superinfections and overgrowth of opportunistic pathogens difficult to eradicate. Peri-implant superinfections with opportunistic bacteria, yeast and viruses, are plausible risks associated to the use of systemic antibiotics in immunocompetent individuals. Lack of microbiological follow-up and antibiotic susceptibility testing may lead to ongoing microbial challenges that exacerbate the disease progression. The increased proliferation of antimicrobial resistance, modern implant surface topography and indiscriminative empiric antibiotic regimens may promote the escalation of peri-implant disease in years to come. A personalized 3-month supportive therapy may help prevent risks by sustaining a normal ecological balance, decreasing specific pathogen proportions and maintaining ideal plaque control. PMID:26761363
Müllertz, Anette; Ogbonna, Anayo; Ren, Shan;
The aim of this review is to highlight relevant considerations when implementing a rational strategy for the development of lipid and surfactant based drug delivery system and to discuss shortcomings and challenges to the current classification of these delivery systems. We also aim to offer...... suggestions for an improved classification system that will accommodate lipid based formulations that are not currently accommodated in the lipid formulation classification system....
Amber Vyas; Avinesh Kumar Sonker; Bina Gidwani
Approximately 95% of the population suffers at some point in their lifetime from acne vulgaris. Acne is a multifactorial disease of the pilosebaceous unit. This inflammatory skin disorder is most common in adolescents but also affects neonates, prepubescent children, and adults. Topical conventional systems are associated with various side effects. Novel drug delivery systems have been used to reduce the side effect of drugs commonly used in the topical treatment of acne. Topical treatment of...
Diane Belyk; Jeremy Schubert; Jon Baggaley
For their optimal use in distance education (DE), online educational applications need to be integrated within a comprehensive course management system (CMS). Such systems are server-based software that supports the development, delivery, administration, and evaluation of online learning environments. The selection of an appropriate CMS should be considered from the multiple perspectives of the student, the course developer, the course instructor/ tutor, the technical support staff, and the D...
ZHANG Feng-li; ZHOU Ming-tian; XU Bo
The development of spatio-temporal database systems is primarily motivated by applications which track and present mobile objects. In this paper, solutions for establishing the moving object database based on GPS/GIS environment are presented, and a data modeling of moving object is given by using Temporal logical to extent the query language, finally the application model in cargo delivery system is shown.
Belgamwar V; Surana S
Oral sustained release gastroretentive dosage forms offer many advantages for drugs having absorption from the upper gastrointestinal tract and improve the bioavailability of medications that are characterized by the narrow absorption window. A new gastroretentive sustained release delivery system using the novel effervescent system was developed with floating, swellable, and bioadhesive properties. Various release retarding polymers like psyllium husk, HPMC K15M, and a swelling agent crosspo...
van Belkum, Alex; Soriaga, Leah B.; LaFave, Matthew C.; Akella, Srividya; Veyrieras, Jean-Baptiste; Barbu, E. Magda; Shortridge, Dee; Blanc, Bernadette; Hannum, Gregory; Zambardi, Gilles; Miller, Kristofer; Enright, Mark C; Mugnier, Nathalie; Brami, Daniel; Schicklin, Stéphane
ABSTRACT Pseudomonas aeruginosa is an antibiotic-refractory pathogen with a large genome and extensive genotypic diversity. Historically, P. aeruginosa has been a major model system for understanding the molecular mechanisms underlying type I clustered regularly interspaced short palindromic repeat (CRISPR) and CRISPR-associated protein (CRISPR-Cas)-based bacterial immune system function. However, little information on the phylogenetic distribution and potential role of these CRISPR-Cas syste...
Ulker, Zeynep; Erkey, Can
Over the past few decades, advances in "aerogel science" have provoked an increasing interest for these materials in pharmaceutical sciences for drug delivery applications. Because of their high surface areas, high porosities and open pore structures which can be tuned and controlled by manipulation of synthesis conditions, nanostructured aerogels represent a promising class of materials for delivery of various drugs as well as enzymes and proteins. Along with biocompatible inorganic aerogels and biodegradable organic aerogels, more complex systems such as surface functionalized aerogels, composite aerogels and layered aerogels have also been under development and possess huge potential. Emphasis is given to the details of the aerogel synthesis and drug loading methods as well as the influence of synthesis parameters and loading methods on the adsorption and release of the drugs. Owing to their ability to increase the bioavailability of low solubility drugs, to improve both their stability and their release kinetics, there are an increasing number of research articles concerning aerogels in different drug delivery applications. This review presents an up to date overview of the advances in all kinds of aerogel based drug delivery systems which are currently under investigation.
Many different types of nanoparticles, magnetic nanoparticles being just a category among them, offer exciting opportunities for technologies at the interfaces between chemistry, physics and biology. Some magnetic nanoparticles have already been utilized in clinical practice as contrast enhancing agents for magnetic resonance imaging (MRI). However, their physicochemical properties are constantly being improved upon also for other biological applications, such as magnetically-guided delivery systems for different therapeutics. By exposure of magnetic nanoparticles with attached therapeutics to an external magnetic field with appropriate characteristics, they are concentrated and retained at the preferred site which enables the targeted delivery of therapeutics to the desired spot. The idea of binding chemotherapeutics to magnetic nanoparticles has been around for 30 years, however, no magnetic nanoparticles as delivery systems have yet been approved for clinical practice. Recently, binding of nucleic acids to magnetic nanoparticles has been demonstrated as a successful non-viral transfection method of different cell lines in vitro. With the optimization of this method called magnetofection, it will hopefully become another form of gene delivery for the treatment of cancer
Full Text Available Sustained release matrix tablets facilitate prolonged and continuous drug release and improve the bioavailability of drugs while avoiding unwanted side effects. Ofloxacin is a broad spectrum antibacterial agent used for treating wide range of gram positive and gram negative infections. The goal in designing sustained or controlled delivery systems is to reduce frequency of dosing or to increase the effectiveness of the drug by localization at the site of action, reducing the dose required, providing uniform drug delivery. Sustained release drug administration means not only prolongation of duration of drug delivery, but the term also implies the predictability and reproducibility of drug release kinetics. The controlled release of drug substances and their effective transport to sites of action can be exploited to maximize the beneficial clinical response and to minimize the incidence of unbeneficial adverse reactions and side effects. Oral ingestion has long been the most convenient and commonly employed route of drug delivery. Indeed, for sustained release systems, oral route of administration has received most of the attention with respect to research on physiological and drug constraints as well as design and testing of products.
Hea-Young Cho; Jun-Hyuk Kang; Lien Ngo; Phuong Tran; Yong-Bok Lee
Solid-self-emulsifying drug delivery system (S-SEDDS) of paclitaxel (Ptx) was developed by the spray drying method with the purpose of improving the low bioavailability (BA) of Ptx. 10% oil (ethyl oleate), 80% surfactant mixture (Tween 80 : Carbitol, 90 : 10, w/w), and 10% cosolvent (PEG 400) were chosen according to their solubilizing capacity. The mean droplet size, zeta potential, and encapsulation efficiency of the prepared S-SEDDS were 16.9 ± 1.53 nm, 12.5 ± 1.66 mV, and 56.2 ± 8.1%, res...
Full Text Available Since hospitals are an important and integral part of the overall health delivery system, this study was carried out to measure the effectiveness of this institution within the system. The records of 633 hospitalized patients in the pediatrics ward of Ghaem Hospital in Mashhad during 1357 (21 March 1978-20 March 1979 has been consulted. More than half of the patients were hospitalized with the following diagnoses: Bronchopneumonia, Gastroentritis, Septicemia, and Malnutrition. Bronchopneumonia peaked in winter, whereas Gastroentritis and Malnutrition peaked in summer. Most of the hospitalized patients were male and the malnutrition was limited to the pre-school children of 1-6 years of age. The importance of these findings in development and utilization of the health delivery system has been discussed and considering the preventable nature of the above mentioned diseases, development and expansion of primary health care activities has been stressed.
Kingsman, A J; Burns, N R; Layton, G T; Adams, S E
The development of technologies to produce recombinant proteins for use in the pharmaceutical industry has made substantial advances, in particular in the area of generating antigens containing multiple copies of important immunological regions. One such antigen-carrier system is based on the ability of a protein encoded by the yeast retrotransposon, Ty, to self-assemble into virus-like particles. Ty-fusion proteins retain this ability to form particles, and a range of hybrid VLPs carrying a variety of heterologous antigens have been produced and shown to induce potent immune responses. In particular, hybrid VLPs carrying the core protein p24 of HIV (p24-VLPs) have been shown to induce antibody and T-cell proliferative responses in both experimental animals and human volunteers, and immunization of rabbits with VLPs carrying the principal neutralizing determinant of HIV (V3-VLPs) resulted in the induction of neutralizing antibody responses and T-cell proliferation. Further studies with V3-VLPs have shown that this particulate antigen stimulates enhanced V3-specific lymphoproliferative responses as compared to whole recombinant gp120 or to V3 peptide conjugated to albumin. The V3-VLPs also induce potent CTL responses following immunization of mice in the absence of adjuvant. These responses are MHC class I restricted and are mediated by CD8-positive cells. These observations therefore demonstrate that hybrid Ty-VLPs induce both humoral and cellular immune responses against HIV and suggest that these immunogens may be important in combatting AIDS and other infections. PMID:7625653
... lives. But there is a growing problem of antibiotic resistance. It happens when bacteria change and become able ... resistant to several common antibiotics. To help prevent antibiotic resistance Don't use antibiotics for viruses like colds ...
Saurabh Kumar et al.
Full Text Available In pharmaceutical industry, various controlled released dosage forms like solid formulation, semi solid formulation and topical preparation have more importance due to efficacy and patient compliance. Topical preparations have some disadvantages like unpleasant odour, greasiness and skin irritation and fail to reach the systemic circulation in sufficient amounts in few cases. This problem is overcome by microsponge delivery system. Microsponges are tiny sponge like spherical and highly porous micro-sized particles with a unique ability for entrapping actives. They offers programmable release active drug into the skin in order to reduce systemic exposure and minimize local cutaneous reactions to active. These MDS’s are closely related to microspheres, and used in the sun screens, creams, ointments, over- the-counter (OTC skin care preparations, recently used in oral drug as well as biopharmaceuticals (peptides, proteins and DNA-based therapeutics drug delivery. The present review introduces microsponge technology along with its synthesis, characterization, programmable parameters and release mechanism of MDS.
D. Nagasamy Venkatesh
Full Text Available Dendrimers are synthetic, highly branched, monodisperse macromolecules of nanometer dimensions with exact and large number of functional groups, distributed with unprecedented control, makes them a promising scaffolds, for drug delivery. Dendrimers serves as an ideal vehicle for cancer therapy, immunology, vaccines, antivirals, biosensors for diagnostics, neuron capture therapy, photodynamic therapy and photo thermal therapy. Dendrimers chemistry is one of the most fascinating and rapidly expanding areas in the field of chemistry. Prior to the dendrimer technology, nanoparticle drug delivery systems were one of the choicest systems owing to their selectivity and stability of therapeutic agents incorporated into the system. However, few drawbacks such as reticuloendothelial system (RES uptake, drug leakage, immunogenicity, hemolytic toxicity, cytotoxicity, hydrophobicity etc., impede the usage of these nanostructures. Further, these shortcomings shall be circumvented by modifying the surface engineering, such as poly ester dendrimer, arginine dendrimer, glycol dendrimer, PEGylated dendrimers etc., Unique properties of uniform size, water solubility, modifiable surface functionality and availability of internal cavities makes them intriguing carrier for biological and drug delivery system. In the present review, we focused on the bioactive agents that can be easily encapsulated into the interior cavity (or chemical attachment, conjugation (or physically adsorbed on to the dendrimer surface to serve the desired properties of the carrier to cater specific needs of the active components, its characterization and application.
Haggstrom, David A; Doebbeling, Bradley N
Cancer care quality measurement and system change may serve as a case example for larger possibilities in the health care system related to other diseases. Cancer care quality gaps and variation exist across both technical and patient-centered cancer quality measures, especially among vulnerable populations. There is a need to develop measures that address the following dimensions of quality and its context: disparities, overuse, patient-centeredness, and uncertainty. Developments that may promote system change in cancer care delivery include changes in the information market, organizational accountability, and consumer empowerment. Information market changes include public cancer care quality reporting, enabled by health information exchange, and incentivized by pay-for-performance. Moving organizational accountability, reimbursement, and quality measurement from individual episodes of care to multiple providers providing coordinated cancer care may address quality gaps associated with the fragmentation of care delivery. Consumer empowerment through new technologies, such as personal health records, may lead to the collection of patient-centered quality measures and promote patient self-management. Across all of these developments, leadership and ongoing research to guide informed system changes will be necessary to transform the cancer care delivery system.
Alyautdin, Renad; Khalin, Igor; Nafeeza, Mohd Ismail; Haron, Muhammad Huzaimi; Kuznetsov, Dmitry
The protective properties of the blood-brain barrier (BBB) are conferred by the intricate architecture of its endothelium coupled with multiple specific transport systems expressed on the surface of endothelial cells (ECs) in the brain's vasculature. When the stringent control of the BBB is disrupted, such as following EC damage, substances that are safe for peripheral tissues but toxic to neurons have easier access to the central nervous system (CNS). As a consequence, CNS disorders, including degenerative diseases, can occur independently of an individual's age. Although the BBB is crucial in regulating the biochemical environment that is essential for maintaining neuronal integrity, it limits drug delivery to the CNS. This makes it difficult to deliver beneficial drugs across the BBB while preventing the passage of potential neurotoxins. Available options include transport of drugs across the ECs through traversing occludins and claudins in the tight junctions or by attaching drugs to one of the existing transport systems. Either way, access must specifically allow only the passage of a particular drug. In general, the BBB allows small molecules to enter the CNS; however, most drugs with the potential to treat neurological disorders other than infections have large structures. Several mechanisms, such as modifications of the built-in pumping-out system of drugs and utilization of nanocarriers and liposomes, are among the drug-delivery systems that have been tested; however, each has its limitations and constraints. This review comprehensively discusses the functional morphology of the BBB and the challenges that must be overcome by drug-delivery systems and elaborates on the potential targets, mechanisms, and formulations to improve drug delivery to the CNS.
Antibiotics are valuable drugs that fight bacterial infections, but our supply of antibiotics is at risk. Existing antibiotics gradually lose their effectiveness due to bacterial resistance, and few new antibiotics are being developed to replace them. A variety of models have been proposed to promote the conservation of existing antibiotics or incentivize private actors, i.e., drug companies, to develop new ones. Previous models, however, all encourage investment in antibiotic research and de...
Gil, Miguel; Pinto, Pedro; Simões, Alexandra S; Póvoa, Pedro; Da Silva, Miguel Mira; Lapão, Luís Velez
About 37 thousand people die per year in Europe due to infections by resistant bacteria. Fighting antimicrobial resistances (AR) is a top priority to save lives and reduce costs. AR is triggered mostly by uncritical antibiotic prescription. This paper presents HAITool, a decision-making information system to support antibiotic prescription. The system was co-developed together with health professionals using Design Science Research Methodology, empowered with innovative data visualization techniques to improve AR management. HAITool includes integrated visualizations of patient, microbiology, and pharmacy data, facilitating clinical decision support, antibiotic prescriptions quality and antibiotic-resistant bacteria monitoring. It also includes an alert module that monitors conformance of antibiotic prescriptions with norms and guidelines. HAITool is evaluated using both the Österle principles and interviews with physicians and infection control team from three participant hospitals. PMID:27577433
Gamma-scintigraphy is applied extensively in the development and evaluation of pharmaceutical delivery systems, particularly for monitoring formulations in the gastrointestinal and respiratory tracts. The radiolabelling is generally achieved by the incorporation of an appropriate radionuclide such as technetium-99m or indium-111 into the formulation or by addition of a non- radioactive isotope such as samarium-152 followed by neutron activation of the final product. Drug delivery systems can be tested in vitro using various techniques like dissolution rate. Since in vitro testing methods are not predictive of in vivo results, such systems should be evaluated in vivo using animal models, especially oral dosage forms. Altered gastrointestinal transit due to individual variation, physiologic factors, or the presence of food may influence bioavailability. Distribution or drug release may be premature or delayed in vivo. Similarly, altered deposition or clearance from other routes of administration such as nasal, ocular, or inhalation may explain drug absorption anomalies. Therefore, there is a growing tendency for new drug delivery systems to be tested, whenever possible, in human subjects in a so called phase 1 clinical evaluation. Gamma- scintigraphy combined with knowledge of physiological and dosage from design can help to identify some of these variables. the resulting insight can be used to accelerate the formulation development process and to ensure success in early clinical trials
Full Text Available Solid-self-emulsifying drug delivery system (S-SEDDS of paclitaxel (Ptx was developed by the spray drying method with the purpose of improving the low bioavailability (BA of Ptx. 10% oil (ethyl oleate, 80% surfactant mixture (Tween 80 : Carbitol, 90 : 10, w/w, and 10% cosolvent (PEG 400 were chosen according to their solubilizing capacity. The mean droplet size, zeta potential, and encapsulation efficiency of the prepared S-SEDDS were 16.9 ± 1.53 nm, 12.5 ± 1.66 mV, and 56.2 ± 8.1%, respectively. In the S-SEDDS, Ptx presents in the form of molecular dispersion in the emulsions or is distributed in an amorphous state or crystalline with very small size. The prepared S-SEDDS formulation showed 70 and 75% dissolution in 60 and 30 min in dissolution medium pH 1.2 and 6.8, respectively. Significant increase (P≤0.05 in the peak concentration (Cmax, the area under the curve (AUC0–∞, and the lymphatic targeting efficiency of Ptx was observed after the oral administration of the Ptx-loaded S-SEDDS to rats (20 mg/kg as Ptx. Our research suggests the prepared Ptx-loaded S-SEDDS can be a good candidate for the enhancement of BA and targeting drug delivery to the lymphatic system of Ptx.
Evren Atlihan Gundogdu
Full Text Available In this study, the potential use of thermotropic liquid crystals as a responsive release system was investigated. Cholesteryl oleyl carbonate liquid crystal (COC has been embedded in nylon membranes by using vacuum filtration methods. In vitro drug release studies were performed by using a fluid/fluid diffusion cell. Sodium salicylate as a model drug penetration study was performed in nylon membrane with or without COC that is prepared at 25 and 37°C. Also the penetration studies were performed by repeatedly exchanging the temperature cycle (10, 25, 37°C of the water bath at predetermined intervals. It was observed that COC and temperature have effects on the penetration of sodium salicylate. At 37 °C, the penetration rate of sodium salicylate was found higher than 25 °C and 10 °C, respectively. Also, the penetration amount of sodium salicylate has changed as pulsatile drug delivery in the presence of COC. As a result, according to the patients’ requirements, it seems that the penetration rate and profile can be adjusted by developing pulsatile drug delivery as a new system.
Full Text Available Many compounds identified through various screening programs are poorly soluble in the water. These molecules are difficult to formulate using the conventional formulation approaches. An important tool in this regard is the use of cyclodextrins, especially chemically modified cyclodextrins. These starch derivatives interact via dynamic complex formation and other mechanisms in a way that camouflages undesirable physicochemical properties, including low aqueous solubility, poor dissolution rate and limited drug stability, which leads to additional benefits such as increased solubility, increased bioavaibility, protection of active molecules from physicochemical degradation and decreased side-eﬀects. This review aims to assess the use of cyclodextrins in newer drug delivery systems such as nanosponges, nanoparticles, nanospheres, nanoassemblies, drug-in cyclodextrin-in deformable liposomes and other drug delivery systems. These approaches are useful for resolving many of the current issues associated with developing and commercializing poorly water soluble drugs.
Joye, Iris J; McClements, D Julian
Biopolymer-based nanostructures or microstructures can be fabricated with different compositions, structures, and properties so that colloidal delivery systems can be tailored for specific applications. These structures can be assembled using various approaches, including electrospinning, coacervation, nanoprecipitation, injection, layer-by-layer deposition, and/or gelation. A major application of biopolymer-based particles is to encapsulate, protect, and release active molecules in the agricultural, food, supplements, personal care, and pharmaceutical sectors. The inherent variability and complexity of biopolymers (proteins and polysaccharides) often makes it challenging to produce particles with well-defined physicochemical and functional attributes. In this review, we discuss the properties of biopolymers, common particle fabrication methods, and some of the major challenges and opportunities associated with developing biopolymer-based particles for application as food-grade delivery systems.
Thakare, Priya; Mogal, Vrushali; Dusane, Jaydeep; Kshirsagar, Sanjay
Improving oral bioavailability of low poorly water soluble drugs using self-emulsifying drug delivery systems (SEDDS) possess significant potential. Oral bioavailability of hydrophobic drugs can be improved using SEDDS, and appears most promising. Their dispersion in gastro intestinal (GI) fluid after administration forms micro or nano emulsified drug which gets easily absorbed through lymphatic pathways bypassing the hepatic first pass metabolism. Parameters like surfactant concentration, oi...
Galblum, Trudi W.; Trieger, Sidney
The current Administration supports competition as one method of helping to contain escalating costs. Proponents of competition claim many advantages to its implementation, but their claims have yet to be widely tested. Over the past several years, however, the Health Care Financing Administration has supported a number of Medicare and Medicaid demonstrations to yield information on plan participation, marketing, and reimbursement under alternative delivery systems. Much of these data are app...
Springer, D.; Dakin, B.; Backman, C.
The primary objectives of this study are to estimate potential energy savings relative to conventional ducted air distribution, and to identify equipment requirements, costs, and barriers with a focus on ductless hydronic delivery systems that utilize water-to-air terminal units in each zone. Results indicate that annual heating and cooling energy use can be reduced by up to 27% assuming replacement of the conventional 13 SEER heat pump and coil with a similarly rated air-to-water heat pump.
Ritu M Gilhotra; Ikram, Mohd; Srivastava, Sunny; Gilhotra, Neeraj
Mucoadhesion can be defined as a state in which two components, of which one is of biological origin, are held together for extended periods of time by the help of interfacial forces. Among the various transmucosal routes, buccal mucosa has excellent accessibility and relatively immobile mucosa, hence suitable for administration of retentive dosage form. The objective of this paper is to review the works done so far in the field of mucoadhesive buccal drug delivery systems (MBDDS), with a cli...
Sujit Bose; Amandeep Kaur; Sharma, S K
Sustained release matrix tablets facilitate prolonged and continuous drug release and improve the bioavailability of drugs while avoiding unwanted side effects. Ofloxacin is a broad spectrum antibacterial agent used for treating wide range of gram positive and gram negative infections. The goal in designing sustained or controlled delivery systems is to reduce frequency of dosing or to increase the effectiveness of the drug by localization at the site of action, reducing the dose required, pr...
Pseudopolyrotaxanes (PPR) consisting of α-cyclodextrin rings and polyethylene glycol axes with end thymine groups have been synthesized and characterized successfully. Fluorescein (Fl) as a model drug was conjugated to the hydroxyl functional groups of cyclodextrin rings of PPR via ester bonds and PPR-Fl as the primary drug delivery system was obtained. Finally PPR-Fl was capped by hydrogen bonds between end thymine groups and a suitable complementary molecule such as polycitric acid, citric ...
Kharia A; Hiremath S; Singhai A; Omray L; Jain S
The purpose of the present work was to design and optimize floating drug delivery systems of acyclovir using psyllium husk and hydroxypropylmethylcellulose K4M as the polymers and sodium bicarbonate as a gas generating agent. The tablets were prepared by wet granulation method. A 32 full factorial design was used for optimization of drug release profile. The amount of psyllium husk (X1) and hydroxypropylmethylcellulose K4M (X2) were selected as independent variables. The times required for 50...
Momen, Natalie; Olsen, Jørn; Gissler, Mika;
to the child’s birth, from 1995 to 2008. Each cancer case, aged 0 to 14 years (n=1,157, including 475 leukemia, 153 central and sympathetic nervous system tumors, and 80 renal tumors), was matched by birthdate and sex with three population-based controls (n=3,471). Conditional logistic regression was used...... antibiotics. We plan to investigate these further with the addition of data from the Swedish national registers and the California Childhood Leukemia Study....
Hirano, S; Agata, N; Hara, Y; Iguchi, H; Shirai, M; Tone, H; Urakawa, N
In the present study we examined the effects of pirarubicin [(2"R)-4'-O-tetrahydropyranyladriamycin, THP] on a cardiovascular system. An injection of THP (0.39-3.13 mg/kg, i.v.) reduced the mean blood pressure and caused an increase in the respiratory air rate in anesthetized rats. At 1.5 x 10(-6)-1.5 x 10(-5) M, THP markedly relaxed a contraction induced by 10(-7) M norepinephrine in rat aorta with endothelium but not in that without endothelium. At a dose of 0.02-0.5 mg, THP produced an increase in the contractile force and the perfusion flow of isolated perfused guinea pig hearts. At a higher concentration (4.5 x 10(-5)-1.5 x 10(-4) M), it produced a slight increase in the contractile force of the left atria in guinea pigs. This positive inotropic action of THP was inhibited by diphenhydramine (10(-6)-5 x 10(-5) M), chlorpheniramine (3 x 10(-7)-3 x 10(-5) M), and tripelennamine (3 x 10(-7)-3 x 10(-5) M) but not by propranolol (10(-6) M), cimetidine (10(-5) M), diltiazem (10(-6) M), or ryanodine (10(-8) M). THP given i.v. at 2.5 mg/kg elevated the plasma histamine level in anesthetized dogs. From these data, we conclude that THP mainly relaxed the rat aorta in the presence of endothelium and that at higher concentrations, it increased the contractile force in the cardiac muscle, probably mediated through the release of histamine.
Kumar D; Saini S; Seth N; Khullar R; Sharma R
This review explains the recent advances in gastroretentive drug delivery systems with special focus on floating drug delivery systems. Oral route is the most convenient and painless technique of drug delivery. Gastroretentive drug delivery systems have been developed which overcome physiological conditions in gastrointestinal tract such as short gastric resident time (GRT) and unpredictable gastric emptying times (GET). Various approaches used for prolonging GRT are mucoadhesive systems (Bio...
Taksande Jayshree B
Full Text Available Oral delivery of poorly water-soluble drugs creates critical problem for their formulation as 35- 40% of new active pharmaceutical ingredients have poor water solubility and frequently associated with low bioavailability. Recently much attention has been given to lipid-based formulation with particular emphasis on self emulsifying drug delivery system (SEDDS to improve the oral bioavailability. These can exist in either liquid or solid states. Self-emulsifying system formulation mainly depends on the nature of oil/lipid excipients, surfactants, their concentration and temperature at which emulsification occurs. As advancement or substitute of conventional liquid SEDDS, Solid SEDDS are better in minimizing manufacturing cost, makes simpler industrial manufacture, enhancing stability, patient compliance and most prominently these are very flexible to develop different solid dosage forms for oral and parentral administration. In addition, such formulation prevents GI irritation and able to control drug release. Recently self emulsifying drug delivery system is used as an efficient approach for the formulation of drugs that are beneficial in the diseases such as hypertension and congestive heart failure, HIV infections, cancer etc. The main difficulty in the development of SEDDS and other lipid-based formulations is the lack of high-quality in vitro models for their evaluation. Finally, the existing problems and the possible future research directions in this field are pointed out.
L. K. Omray
Full Text Available Gastro retentive drug delivery system of diltiazem hydrochloride was designed and evaluated for its effectiveness for the management of mild to moderate hypertension. Gastro retentive drug delivery system were prepared using polyvinyl alcohol and sodium carboxy methyl cellulose as the polymers and sodium bicarbonate as a gas generating agent for the reduction of floating lag time. Gastro retentive drug delivery system tablets were prepared by wet granulation method by compression in tablet compression machine. Formulations DL1, DL2, DL3, DL4 and DL5 were developed which differed in the ratio of polyvinyl alcohol and sodium carboxy methyl cellulose polymers. All the formulations were evaluated for hardness, weight variation, friability, drug content, swelling index, buoyancy studies and in vitro drug release study. In vitro drug release study was performed using United State Pharmacopoeia 23 type 2 dissolution test apparatus employing paddle stirrer at 50 r/pm. Dissolution medium was 900 ml of 0.1N hydrochloric acid at 37ºC ± 3ºC. Formulations DL3 was found to be better as compared to other formulation.
González-Aramundiz, José Vicente; Peleteiro Olmedo, Mercedes; González-Fernández, África; Alonso Fernández, María José; Csaba, Noemi Stefánia
The use of biodegradable nanoparticles as antigen delivery vehicles is an attractive approach to overcome the problems associated with the use of Alum-based classical adjuvants. Herein we report, the design and development of protamine-based nanoparticles as novel antigen delivery systems, using recombinant hepatitis B surface antigen as a model viral antigen. The nanoparticles, composed of protamine and a polysaccharide (hyaluronic acid or alginate), were obtained using a mild ionic cross-linking technique. The size and surface charge of the nanoparticles could be modulated by adjusting the ratio of the components. Prototypes with optimal physicochemical characteristics and satisfactory colloidal stability were selected for the assessment of their antigen loading capacity, antigen stability during storage and in vitro and in vivo proof-of-concept studies. In vitro studies showed that antigen-loaded nanoparticles induced the secretion of cytokines by macrophages more efficiently than the antigen in solution, thus indicating a potential adjuvant effect of the nanoparticles. Finally, in vivo studies showed the capacity of these systems to trigger efficient immune responses against the hepatitis B antigen following intramuscular administration, suggesting the potential interest of protamine-polysaccharide nanoparticles as antigen delivery systems.
Tabansky, Inna; Messina, Mark D; Bangeranye, Catherine; Goldstein, Jeffrey; Blitz-Shabbir, Karen M; Machado, Suly; Jeganathan, Venkatesh; Wright, Paul; Najjar, Souhel; Cao, Yonghao; Sands, Warren; Keskin, Derin B; Stern, Joel N H
Multiple sclerosis (MS) is a chronic inflammatory autoimmune disease of the central nervous system. It is characterized by demyelination of neurons and loss of neuronal axons and oligodendrocytes. In MS, auto-reactive T cells and B cells cross the blood-brain barrier (BBB), causing perivenous demyelinating lesions that form multiple discrete inflammatory demyelinated plaques located primarily in the white matter. In chronic MS, cortical demyelination and progressive axonal transections develop. Treatment for MS can be stratified into disease-modifying therapies (DMTs) and symptomatic therapy. DMTs aim to decrease circulating immune cells or to prevent these cells from crossing the BBB and reduce the inflammatory response. There are currently 10 DMTs approved for the relapsing forms of MS; these vary with regard to their efficacy, route and frequency of administration, adverse effects, and toxicity profile. Better drug delivery systems are being developed in order to decrease adverse effects, increase drug efficacy, and increase patient compliance through the direct targeting of pathologic cells. Here, we address the uses and benefits of advanced drug delivery systems, including nanoparticles, microparticles, fusion antibodies, and liposomal formulations. By altering the properties of therapeutic particles and enhancing targeting, breakthrough drug delivery technologies potentially applicable to multiple disease treatments may rapidly emerge.
Doroud, Delaram; Rafati, Sima
Although mass vaccination of the entire population of an endemic area would be the most cost-effective tool to diminish Leishmania burden, an effective vaccine is not yet commercially available. Practically, vaccines have failed to achieve the required level of protection, possibly owing to the lack of an appropriate adjuvant and/or delivery system. Therefore, there is still an imperative demand for an improved, safe and efficient delivery system to enhance the immunogenicity of available vaccine candidates. Nanoparticles are proficient in boosting the quality and magnitude of immune responses in a predictable fashion. Herein, we discuss how nanoparticulate vaccine delivery systems can be used to induce appropriate immune responses against leishmaniasis by controlling physicochemical properties of the vaccine. Stability, production reproducibility, low cost per dose and low risk-benefit ratios are desirable characteristics of an ideal vaccine formulation and solid lipid nanoparticles may serve as one of the most promising practical strategies to help to achieve such a leishmanial vaccine, at least in canine species in the developing world.
Fireman, Sharon; Toledano, Ofer; Neimann, Karine; Loboda, Natalia; Dayan, Nava
The introduction of new topical drugs based on new chemical entities has become a rare event. Instead, pharmaceutical companies have been focused on reformulating existing drugs resulting in an ever-growing number of topical drug products for every approved drug substance. In light of this trend, soon reformulations may not be as rewarding to their sponsors as they are today unless they offer a substantial improvement over other formulations of the same drug substance and the same indication, namely improved efficacy over existing drugs, reduced side effects, unique drug combinations, or applicability for new indications. This article reviews and compares topical drug delivery systems currently under active research that are designed to offer such advantages in the coming years. The reviewed delivery systems are: liposomes, niosomes, transferosomes, ethosomes, solid lipid nanoparticles, nanostructured lipid carriers, cyclodextrin, and sol-gel microcapsules. Among all the topical drug delivery systems currently undergoing active research, only the sol-gel microencapsulation is at clinical stages. PMID:22353154
Yang, Jeehong; Savari, Serap A.
The data delivery throughput of electron beam lithography systems can be improved by applying lossless image compression to the layout image and using an electron beam writer that can decode the compressed image on-the-fly. In earlier research we introduced the lossless layout image compression algorithm Corner2, which assumes a somewhat idealized writing strategy, namely row-by-row with a raster order. The MAPPER system has electron beam writers positioned in a lattice formation and each electron beam writer writes a designated block in a zig-zag order. We introduce Corner2-MEB, which redesigns Corner2 for MAPPER systems.
CUI Qi-feng; LIU Cheng-liang; ZHA Xuan F
A novel intelligent drug delivery system potential for the more effective therapy of the diabeticswas proposed, and the composition of system was analyzed. Based on the design of micro-electro-mechanicalsystems (MEMS), an iterative modeling process was introduced. Unified modeling language (UML) was em-ployed to describe the function requirement, and different diagrams were built up to explore the static model,the dynamic model and the employment model. The mapping analysis of different diagrams can simply verifythe consistency and completeness of the system model.
Gomes, Weglis Dyanne de Souza; Silva, Cristina Antoniali; Melo, Moriel Evangelista; Silva, Vanessa Ferreira da; Almeida, Melyna Marques de; Pedrini, Denise; Poi, Wilson Roberto; Sonoda, Celso Koogi; Panzarini, Sônia Regina
Systemic antibiotic therapy (SAT) has usually been recommended after tooth replantation, but its actual value has been questioned. As there are no reports in the literature about its influence on tooth replantation, the aim of this study was to evaluate the influence of systemic administration of antibiotics (amoxicillin and tetracycline) at the different phases of the repair process (7, 15, 30 days) in delayed rat tooth replantation. Ninety Wistar rats (Rattus norvegicus albinus) had their maxillary right incisors extracted and bench-dried for 60 min. The dental papilla, enamel organ, pulp tissue, and root surface-adhered periodontal ligament were removed, and the teeth were replanted. The animals received no antibiotics (n = 30) or were medicated systemically with amoxicillin (n = 30) and tetracycline (n = 30), and were euthanized after 7, 15, and 30 days. Regardless of the evaluation period, the acute inflammatory infiltrate was less intense and root resorption presented smaller extent and depth in the group treated with amoxicillin. The results suggest that SAT has a positive influence on the repair process in delayed tooth replantation and that amoxicillin is an excellent treatment option. PMID:26332890
Lopes, Carla M; Bettencourt, Catarina; Rossi, Alessandra; Buttini, Francesca; Barata, Pedro
In recent decades, many efforts have been made in order to improve drug bioavailability after oral administration. Gastroretentive drug delivery systems are a good example; they emerged to enhance the bioavailability and effectiveness of drugs with a narrow absorption window in the upper gastrointestinal tract and/or to promote local activity in the stomach and duodenum. Several strategies are used to increase the gastric residence time, namely bioadhesive or mucoadhesive systems, expandable systems, high-density systems, floating systems, superporous hydrogels and magnetic systems. The present review highlights some of the drugs that can benefit from gastroretentive strategies, such as the factors that influence gastric retention time and the mechanism of action of gastroretentive systems, as well as their classification into single and multiple unit systems.
Lopes, Carla M; Bettencourt, Catarina; Rossi, Alessandra; Buttini, Francesca; Barata, Pedro
In recent decades, many efforts have been made in order to improve drug bioavailability after oral administration. Gastroretentive drug delivery systems are a good example; they emerged to enhance the bioavailability and effectiveness of drugs with a narrow absorption window in the upper gastrointestinal tract and/or to promote local activity in the stomach and duodenum. Several strategies are used to increase the gastric residence time, namely bioadhesive or mucoadhesive systems, expandable systems, high-density systems, floating systems, superporous hydrogels and magnetic systems. The present review highlights some of the drugs that can benefit from gastroretentive strategies, such as the factors that influence gastric retention time and the mechanism of action of gastroretentive systems, as well as their classification into single and multiple unit systems. PMID:27173823
Kwon, S I; Owens, G; Ok, Y S; Lee, D B; Jeon, W-T; Kim, J G; Kim, K-R
The effluence of veterinary antibiotics (VAs) to aquatic and terrestrial environments is of concern due to the potential adverse effects on human health, such as the production of antibiotic resistant bacteria. One of the main pathways for antibiotics to enter the environment is via the application of manure and/or manure-based composts as an alternative organic fertilizer to agricultural lands. While a wide diversity of manure-based composts are produced in Korea, there is currently no regulatory guideline for VA residues. Hence, monitoring and limiting the concentration of VA residues in manure and/or manure-based composts prior to application to the lands is important to mitigate any environmental burden. The current study was conducted to examine the applicability of the Charm II antibiotic test system for monitoring tetracyclines, sulfonamides and macrolides in manure-based composts. The Charm II system was a highly reproducible method for determining whether VA residue concentrations in manure-based compost exceeded specific guideline values. A wide range of manure-based composts and liquid fertilizers commercially available in Korea were examined using the Charm II system to monitor the residues of the target VAs. For this, the guideline concentrations of VA residues (0.8 mg kg(-1) for tetracyclines, 0.2 mg kg(-1) for sulfonamides, and 0.1 mg kg(-1) for macrolides) stated in 'Official Standard of Feeds' under the 'Control of Livestock and Fish Feed Act' in Korea were adopted to establish control points. Of the 70 compost samples examined 12 exceeded 0.8 mg kg(-1) for tetracyclines and 21 exceeded 0.2 mg kg(-1) for sulfonamides. Of the 25 liquid fertilizer samples examined most samples exceeded these prospective guidelines.
Kuznetsova, Ekaterina; Bettenay, Sonya; Nikolaeva, Lyubov; Majzoub, Monir; Mueller, Ralf
Canine generalized demodicosis (CGD) is a skin disease with distinct breed predispositions. Secondary bacterial infections are common. Dogs typically receive miticidal therapy in combination with antibacterial treatment. Whether antibiotics influence the duration of acaricidal therapy is unknown at the moment. There is also debate over how common short-tailed Demodex mites occur in demodicosis. This study evaluated the influence of systemic antibiotics on the course of CGD, the occurrence of short-tailed Demodex mites in demodectic dogs and the influence of furunculosis on treatment outcome. Breed predispositions for CGD in Moscow were identified. Fifty-eight dogs were randomly distributed in two groups. Both were treated with ivermectin 600 mcg/kg q24h orally and benzoyl peroxide shampoo weekly. The dogs in one group (AB) were additionally treated with systemic antibiotics for at least 1 month, dogs in the other group (NAB) were not. Monthly examinations, skin scrapings and impression smears were performed. Prior to the study there was no difference in clinical severity, presence of pyoderma and mite numbers between groups. There was no significant difference in duration until first negative skin scrapings and resolution of bacterial infection. In dogs with furunculosis the number of the mites was significantly higher than in dogs without furunculosis but the duration until microscopic remission albeit longer, was not significantly different. Short-tailed Demodex mites were found in 25% of the cases. Pugs and English Bulldogs were predisposed. Based on these results, systemic antibiotics may not impact as much as previously thought on the actual success of CGD treatment.
Kuznetsova, Ekaterina; Bettenay, Sonya; Nikolaeva, Lyubov; Majzoub, Monir; Mueller, Ralf
Canine generalized demodicosis (CGD) is a skin disease with distinct breed predispositions. Secondary bacterial infections are common. Dogs typically receive miticidal therapy in combination with antibacterial treatment. Whether antibiotics influence the duration of acaricidal therapy is unknown at the moment. There is also debate over how common short-tailed Demodex mites occur in demodicosis. This study evaluated the influence of systemic antibiotics on the course of CGD, the occurrence of short-tailed Demodex mites in demodectic dogs and the influence of furunculosis on treatment outcome. Breed predispositions for CGD in Moscow were identified. Fifty-eight dogs were randomly distributed in two groups. Both were treated with ivermectin 600 mcg/kg q24h orally and benzoyl peroxide shampoo weekly. The dogs in one group (AB) were additionally treated with systemic antibiotics for at least 1 month, dogs in the other group (NAB) were not. Monthly examinations, skin scrapings and impression smears were performed. Prior to the study there was no difference in clinical severity, presence of pyoderma and mite numbers between groups. There was no significant difference in duration until first negative skin scrapings and resolution of bacterial infection. In dogs with furunculosis the number of the mites was significantly higher than in dogs without furunculosis but the duration until microscopic remission albeit longer, was not significantly different. Short-tailed Demodex mites were found in 25% of the cases. Pugs and English Bulldogs were predisposed. Based on these results, systemic antibiotics may not impact as much as previously thought on the actual success of CGD treatment. PMID:22575280
Kshirsagar, N A; Pandya, S K; Kirodian, G B; Sanath, S
The main objective of drug delivery systems is to deliver a drug effectively, specifically to the site of action and to achieve greater efficacy and minimise the toxic effects compared to conventional drugs. Amongst various carrier systems, liposomes have generated a great interest because of their versatility. Liposomes are vesicular concentric bilayered structures, which are biocompatible, biodegradable and nonimmumnogenic. They can control the delivery of drugs by targeting the drug to the site of action or by site avoidance drug delivery or by prolonged circulation of drugs. Amphotericin B (Amp B) remains the drug of choice in most systemic mycoses and also as a second line treatment for Kala azar. However, its toxic effects often limit its use. Although the liposome delivery system has been tried for several drugs, only a few have been used in patients due to the slow development of necessary large-scale pharmaceutical procedures. This paper reviews the development of the technique for liposomal Amphotericin B (L-Amp-LRC-1, Fungisome) drug delivery system in our laboratory in collaboration with the department of Biochemistry, Delhi University in India and proving the safety and efficacy of this preparation in clinical practice. It also attempts to compare the efficacy and benefits of our product for Indian patients with those of similar products and it includes facts from the publications that flowed from our work. As compared to conventional Amp B, Fungisome is infused over a much shorter period requiring a smaller volume and no premedication. It was found to be safe in patients who had developed serious unacceptable toxicity with conventional Amp B. In renal transplant patients, Fungisome did not produce any nephrotoxicity. Fungisome is effective in fungal infections resistant to fluconazole, conventional Amp B and in virgin and resistant cases of visceral leishmaniasis. The cost of any drug is of great significance, especially in India. We have therefore
Full Text Available The main objective of drug delivery systems is to deliver a drug effectively, specifically to the site of action and to achieve greater efficacy and minimise the toxic effects compared to conventional drugs. Amongst various carrier systems, liposomes have generated a great interest because of their versatility. Liposomes are vesicular concentric bilayered structures, which are biocompatible, biodegradable and nonimmumnogenic. They can control the delivery of drugs by targeting the drug to the site of action or by site avoidance drug delivery or by prolonged circulation of drugs. Amphotericin B (Amp B remains the drug of choice in most systemic mycoses and also as a second line treatment for Kala azar. However, its toxic effects often limit its use. Although the liposome delivery system has been tried for several drugs, only a few have been used in patients due to the slow development of necessary large-scale pharmaceutical procedures. This paper reviews the development of the technique for liposomal Amphotericin B (L-Amp-LRC-1, FungisomeTM drug delivery system in our laboratory in collaboration with the department of Biochemistry, Delhi University in India and proving the safety and efficacy of this preparation in clinical practice. It also attempts to compare the efficacy and benefits of our product for Indian patients with those of similar products and it includes facts from the publications that flowed from our work. As compared to conventional Amp B, Fungisome is infused over a much shorter period requiring a smaller volume and no premedication. It was found to be safe in patients who had developed serious unacceptable toxicity with conventional Amp B. In renal transplant patients, Fungisome did not produce any nephrotoxicity. Fungisome is effective in fungal infections resistant to fluconazole, conventional Amp B and in virgin and resistant cases of visceral leishmaniasis. The cost of any drug is of great significance, especially in India
Complete text of publication follows. Drug targeting is the delivery of drugs to receptors or organs or any other specific part of the body to which one wishes to deliver the drug exclusively. The concept of designing a specified delivery system to achieve selective drug targeting has been originated from the perception of Paul Ehrlich, who proposed drug delivery to be as a 'magic bullet', where a drug-carrier complex/conjugate, delivers drug(s) exclusively to the preselected target cells in a specific manner. Through the novel biomaterials chitin and chitosan are intensively studied due to its many potential applications as a pharmaceutical drug carrier. Modern biocompatible systems target not only infectious diseases, but also autoimmune disorders, allergies, chronic inflammatory diseases and cancer. The study was aimed to develop and characterize a novel polyelectrolyte complex (PEC) chitosan with Tween-80 and oleic acid as drug carrier for controlled drug delivery, with possible use in skin burnt painfull injuries. The PEC chitosan complexes were prepared by coacervation method using the same ratios of Tween-80, oleic acid and chitosan. Diclofenac sodium (DCF) is used as model drug because it is one of the most useful non-steroidal anti-inflammatory drugs (NSAIDs). The use of chitosan as base in polyelectrolite complex systems, to prepare liquid release systems as hydrogels and solid release systems as sponges is presented. In this paper is reported the preparation of chitosan (CS) hydrogels and sponges carrying diclofenac (DCF), as anti-inflammatory drug. The immobilisation of DCF in chitosan is done by mixing the chitosan hydrogel with the anti-inflammatory drug solutions. Chitosan sponges with anti-inflammatory drugs were prepared by freeze-drying at -61 deg C and 0.009 atm. The characterization of the hydrogels and sponges was done by FTIR and UV-VIS spectroscopy, spectrofluorimetry and differential scanning calorimetry (DSC). The results indicated the
Oyewumi, Moses O; Wehrung, Daniel; Sadana, Prabodh
Clinical viability of gene delivery systems has been greatly impacted by potential toxicity of the delivery systems. Recently, we reported the nanoparticle (NP) preparation process that employs biocompatible materials such as Gelucire® 44/14 and cetyl alcohol as matrix materials. In the current study, the NP preparation was modified for pDNA loading through: (i) inclusion of cationic lipids (DOTAP or DDAB) with NP matrix materials; or (ii) application of cationic surfactants (CTAB) to generate NPs with desired surface charges for pDNA complexation. Colloidal stability and efficiency of loading pGL3-DR4X2-luciferase plasmid DNA in NPs were verified by gel permeation chromatography. Compared to pDNA alone, all the NPs were effective in preserving pDNA from digestion by DNase. While pDNA loading using CTAB-NPs involved fewer steps compared to DOTAP-NPs and DDAB-NPs, CTAB-NPs were greatly impacted by elevated cytotoxicity level which could be ascribed to the concentrations of CTAB in NP formulations. In vitro transfection studies (in HepG2 cells) based on luciferase expression showed the ranking of cell transfection efficiency as DOTAP-NPs > DDAB-NPs > CTAB-NPs. The overall work provided an initial assessment of gelucire-stabilized NPs as a potential platform for gene delivery. PMID:25915179
Full Text Available The in-vivo targeting of tumors with magnetic microspheres is currently realized through the applicationof external non-uniform magnetic fields generated by rare-earth permanent magnets or electromagnets.This technique can be applied to magnetically targeted cancer therapy, magnetic embolization therapywith magnetic particles that contain anticancer agent, such as chemotherapeutic drugs or therapeuticradioisotopes. Drug targeting is one way of local or regional antitumor treatment. Magneticallycontrolled drug targeting is one of the various possible ways of drug targeting. This technology is basedon binding establish anticancer drug with ferrofluids that concentrate the drug in the area of interest(tumor site by means of magnetic fields. There has been keen interest in the development of amagnetically target drug delivery system. These drug delivery systems aims to deliver the drug at a ratedirected by the needs of the body during the period of treatment, and target the activity entity to the siteof action. This paper gives an overview of current application of magnetic microspheres (ferrofluid inconjunction with magnetic fields as they relate to the latest advances in medical application and inparticular to anticancer therapy and also discuss about mechanism of magnetic targeted delivery, drugrelease rate in-vitro, benefits and drawbacks of magnetic targeting.
Jaiswal, Parul; Aggarwal, Geeta; Harikumar, Sasidharan Leelakumari; Singh, Kashmir
Objective: Self-microemulsifying drug delivery system (SMEDDS) and solid-SMEDDS of telmisartan was aimed at overcoming the problems of poor solubility and bioavailability. Methodology: The formulation strategy included selection of oil phase based on saturated solubility studies and surfactant and co-surfactant screening on the basis of their emulsification ability. Ternary phase diagrams were constructed to identify the self-emulsifying region using a dilution method. The prepared formulatio...
Fillat, Cristina, E-mail: firstname.lastname@example.org; Jose, Anabel; Ros, Xavier Bofill-De; Mato-Berciano, Ana; Maliandi, Maria Victoria; Sobrevals, Luciano [Programa Gens i Malaltia, Centre de Regulació Genòmica-CRG, UPF, Parc de Recerca Biomedica de Barcelona-PRBB and Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Barcelona (Spain)
The continuous identification of molecular changes deregulating critical pathways in pancreatic tumor cells provides us with a large number of novel candidates to engineer gene-targeted approaches for pancreatic cancer treatment. Targets—both protein coding and non-coding—are being exploited in gene therapy to influence the deregulated pathways to facilitate cytotoxicity, enhance the immune response or sensitize to current treatments. Delivery vehicles based on viral or non-viral systems as well as cellular vectors with tumor homing characteristics are a critical part of the design of gene therapy strategies. The different behavior of tumoral versus non-tumoral cells inspires vector engineering with the generation of tumor selective products that can prevent potential toxic-associated effects. In the current review, a detailed analysis of the different targets, the delivery vectors, the preclinical approaches and a descriptive update on the conducted clinical trials are presented. Moreover, future possibilities in pancreatic cancer treatment by gene therapy strategies are discussed.
Full Text Available In the injured spinal cord, chondroitin sulfate proteoglycans (CSPGs are the principal responsible of axon growth inhibition and they contribute to regenerative failure, promoting glial scar formation. Chondroitinase ABC (chABC is known for being able to digest proteoglycans, thus degrading glial scar and favoring axonal regrowth. However, its classic administration is invasive, infection-prone and clinically problematic. An agarose-carbomer (AC1 hydrogel, already used in SCI repair strategies, was here investigated as a delivery system capable of an effective chABC administration: the material ability to include chABC within its pores and the possibility to be injected into the target tissue were firstly proved. Subsequently, release kinetic and the maintenance of enzymatic activity were positively assessed: AC1 hydrogel was thus confirmed to be a feasible tool for chABC delivery and a promising device for spinal cord injury topic repair strategies.
Torchilin, Vladimir P
The use of nanoparticulate pharmaceutical drug delivery systems (NDDSs) to enhance the in vivo effectiveness of drugs is now well established. The development of multifunctional and stimulus-sensitive NDDSs is an active area of current research. Such NDDSs can have long circulation times, target the site of the disease and enhance the intracellular delivery of a drug. This type of NDDS can also respond to local stimuli that are characteristic of the pathological site by, for example, releasing an entrapped drug or shedding a protective coating, thus facilitating the interaction between drug-loaded nanocarriers and target cells or tissues. In addition, imaging contrast moieties can be attached to these carriers to track their real-time biodistribution and accumulation in target cells or tissues. Here, I highlight recent developments with multifunctional and stimuli-sensitive NDDSs and their therapeutic potential for diseases including cancer, cardiovascular diseases and infectious diseases. PMID:25287120
Filipovic, Nenad; Zivanovic, Marko; Savic, Andrej; Bijelic, Goran
The architecture and composition of stratum corneum act as barriers and limit the diffusion of most drug molecules and ions. Much effort has been made to overcome this barrier and it can be seen that iontophoresis has shown a good effect. Iontophoresis represents the application of low electrical potential to increase the transport of drugs into and across the skin or tissue. Iontophoresis is a noninvasive drug delivery system, and therefore, it is a useful alternative to drug transportation by injection. In this study, we present a numerical model and effects of electrical potential on the drug diffusion in the buccal tissue and the stratum corneum. The initial numerical results are in good comparison with experimental observation. We demonstrate that the application of an applied voltage can greatly improve the efficacy of localized drug delivery as compared to diffusion alone. PMID:26592537
Jasvir Singh* and Pawan Deep
Full Text Available ABSTRACT: As an alternative to injection pharmaceutical researcher and scientist are trying to explore transdermal and transmucosal route over the last few years. To overcome the deficiency associated with the other route of administration buccal region of oral cavity is an alternative target for the administration of choice of drug. The disadvantages relative with the oral drug delivery is the extensive presystemic metabolism, instability in acidic medium as a result inadequate absorption of the drugs. However parental route may overcome the drawback related with the oral route but these formulations have high cost, supervision is required and least patient compliance. By the buccal route the drug are directly pass through into systemic circulation, less hepatic metabolism and high bioavailability. The aim of the review article is an overview of buccal drug delivery, anatomy of oral mucosa, mechanism of drug penetration and their in-vitro and in-vivo mucoadhesion testing method.
Full Text Available Drug delivery via sublingual mucous membrane is considered to be a promising alternative to the oral route. This route is useful when rapid onset of action is desired as in the case of antiemetics such as ondansetron. In terms of permeability, the sublingual area of the oral cavity is more permeable than cheek and palatal areas of mouth. The drug absorbed via sublingual blood vessels bypasses the hepatic first-pass metabolic processes giving acceptable bioavailability with low doses and hence decreases the side effects. Sublingual drug delivery system is convenient for paediatric, geriatric, and psychiatric patients with dysphagia. This review highlights the different sublingual dosage forms, advantages, factors affecting sublingual absorption, pharmacology of ondasetron, methods of preparation and various in vitro and in vivo evaluation parameters of sublingual tablet of ondansetron
The continuous identification of molecular changes deregulating critical pathways in pancreatic tumor cells provides us with a large number of novel candidates to engineer gene-targeted approaches for pancreatic cancer treatment. Targets—both protein coding and non-coding—are being exploited in gene therapy to influence the deregulated pathways to facilitate cytotoxicity, enhance the immune response or sensitize to current treatments. Delivery vehicles based on viral or non-viral systems as well as cellular vectors with tumor homing characteristics are a critical part of the design of gene therapy strategies. The different behavior of tumoral versus non-tumoral cells inspires vector engineering with the generation of tumor selective products that can prevent potential toxic-associated effects. In the current review, a detailed analysis of the different targets, the delivery vectors, the preclinical approaches and a descriptive update on the conducted clinical trials are presented. Moreover, future possibilities in pancreatic cancer treatment by gene therapy strategies are discussed
Ajazuddin; Saraf, S
Over the past several years, great advances have been made on development of novel drug delivery systems (NDDS) for plant actives and extracts. The variety of novel herbal formulations like polymeric nanoparticles, nanocapsules, liposomes, phytosomes, nanoemulsions, microsphere, transferosomes, and ethosomes has been reported using bioactive and plant extracts. The novel formulations are reported to have remarkable advantages over conventional formulations of plant actives and extracts which include enhancement of solubility, bioavailability, protection from toxicity, enhancement of pharmacological activity, enhancement of stability, improved tissue macrophages distribution, sustained delivery, and protection from physical and chemical degradation. The present review highlights the current status of the development of novel herbal formulations and summarizes their method of preparation, type of active ingredients, size, entrapment efficiency, route of administration, biological activity and applications of novel formulations. PMID:20471457
August, D A; Faubion, W C; Ryan, M L; Haggerty, R H; Wesley, J R
The financial, entrepreneurial, administrative, and legal forces acting within the home care arena make it difficult for clinicians to develop and operate home care initiatives within an academic setting. HomeMed is a clinician-initiated and -directed home care delivery system wholly owned by the University of Michigan. The advantages of a clinician-directed system include: Assurance that clinical and patient-based factors are the primary determinants of strategic and procedural decisions; Responsiveness of the system to clinician needs; Maintenance of an important role for the referring physician in home care; Economical clinical research by facilitation of protocol therapy in ambulatory and home settings; Reduction of lengths of hospital stays through clinician initiatives; Incorporation of outcome analysis and other research programs into the mission of the system; Clinician commitment to success of the system; and Clinician input on revenue use. Potential disadvantages of a clinician-based system include: Entrepreneurial, financial, and legal naivete; Disconnection from institutional administrative and data management resources; and Inadequate clinician interest and commitment. The University of Michigan HomeMed experience demonstrates a model of clinician-initiated and -directed home care delivery that has been innovative, profitable, and clinically excellent, has engendered broad physician, nurse, pharmacist, and social worker enthusiasm, and has supported individual investigator clinical protocols as well as broad outcomes research initiatives. It is concluded that a clinician-initiated and -directed home care program is feasible and effective, and in some settings may be optimal. PMID:8242586
Full Text Available Joint prostheses chronic infection requires surgical removal of the implant, in order to eradicate the infection process. The Polymethylmethacrylate (PMMA bone cement is a good carrier for the sustained antibiotic release at the site of infection. PMMA cements pre-loaded with antibiotics are utilized for prophylaxis, primary surgical procedure and the treatment of prosthetic joint infections. The mechanical and functional characteristics of the spacers allow a good joint range of motion, weight-bearing in selected cases and a sustained release of antibiotic at the site of infection. These drug delivery systems offer the advantage of local release of high antibiotic concentrations, which considerably exceed those obtained after systemic administration. Nowadays treatment with a preformed antibiotic loaded spacer can be considered a good option for joint prostheses infection maintaining joint function at the intermediate stage in two-stage treatment.
Full Text Available The challenge of modern drug therapy is the optimization of the pharmacological action of the drugs coupled with the reduction of their toxic effects in vivo. The prime objectives in the design of drug delivery systems (DDS are the controlled delivery of the drug to its site of action at a therapeutically optimal rate and dosage to avoid toxicity and improve the drug effectiveness and therapeutic index. DDS has improved many of the pharmacological properties of conventional ("free" drugs including particulate carriers which are primarily composed of lipids and/or polymers and their associated therapeutics. It alters the pharmacokinetics (PK and biodistribution (BD of the associated drugs or functions as drug reservoir or both. Nanoparticles provide a range of new opportunities to increase the targeting of currently approved diagnostic and therapeutic agents to cancers. Nanoparticles carrying a chemotherapeutic can reduce the undesirable distribution of such agents. The problems related to cancer chemotherapy can partially be overcome by direct intratumoral delivery of controlled release biodegradable nanoparticles (NPs.
Cardoso, Ana M; Morais, Catarina M; Cruz, A Rita; Silva, Sandra G; do Vale, M Luísa; Marques, Eduardo F; de Lima, Maria C Pedroso; Jurado, Amália S
Gemini surfactants have been extensively used for in vitro gene delivery. Amino acid-derived gemini surfactants combine the special aggregation properties characteristic of the gemini surfactants with high biocompatibility and biodegradability. In this work, novel serine-derived gemini surfactants, differing in alkyl chain lengths and in the linker group bridging the spacer to the headgroups (amine, amide and ester), were evaluated for their ability to mediate gene delivery either per se or in combination with helper lipids. Gemini surfactant-based DNA complexes were characterized in terms of hydrodynamic diameter, surface charge, stability in aqueous buffer and ability to protect DNA. Efficient formulations, able to transfect up to 50% of the cells without causing toxicity, were found at very low surfactant/DNA charge ratios (1/1-2/1). The most efficient complexes presented sizes suitable for intravenous administration and negative surface charge, a feature known to preclude potentially adverse interactions with serum components. This work brings forward a new family of gemini surfactants with great potential as gene delivery systems. PMID:25513958
Tsai, Han-Kuan A.; Ma, Kuo-Sheng; Zoval, Jim; Kulinsky, Lawrence; Madou, Marc
The most common methods for the drug delivery are swallowing pills or receiving injections. However, formulations that control the rate and period of medicine (i.e., time-release medications) are still problematic. The proposed implantable devices which include batteries, sensors, telemetry, valves, and drug storage reservoirs provide an alternative method for the responsive drug delivery system . Using this device, drug concentration can be precisely controlled which enhances drug efficiency and decreases the side effects. In order to achieve responsive drug delivery, a reliable release valve has to be developed. Biocompatibility, low energy consumption, and minimized leakage are the main requirements for such release method. A bilayer structure composed of Au/PPy film is fabricated as a flap to control the release valve. Optimized potentiostatic control to synthesize polypyrrole (PPy) is presented. The release of miniaturize valve is tested and showed in this paper. A novel idea to simultaneously fabricate the device reservoirs as well as protective packaging is proposed in this paper. The solution of PDMS permeability problem is also mentioned in this article.
Edward A. Shipton
Full Text Available Part 2 of this paper deals with the techniques for drug delivery of topical and injectable local anaesthetics. The various routes of local anaesthetic delivery (epidural, peripheral, wound catheters, intra-nasal, intra-vesical, intra-articular, intra-osseous are explored. To enhance transdermal local anaesthetic permeation, additional methods to the use of an eutectic mixture of local anaesthetics and the use of controlled heat can be used. These methods include iontophoresis, electroporation, sonophoresis, and magnetophoresis. The potential clinical uses of topical local anaesthetics are elucidated. Iontophoresis, the active transportation of a drug into the skin using a constant low-voltage direct current is discussed. It is desirable to prolong local anaesthetic blockade by extending its sensory component only. The optimal release and safety of the encapsulated local anaesthetic agents still need to be determined. The use of different delivery systems should provide the clinician with both an extended range and choice in the degree of prolongation of action of each agent.
Panapisal, Vipaporn; Charoensri, Sawitree; Tantituvanont, Angkana
Silymarin is a standardized extract from Silybum marianum seeds, known for its many skin benefits such as antioxidant, anti-inflammatory, and immunomodulatory properties. In this study, the potential of several microemulsion formulations for dermal delivery of silymarin was evaluated. The pseudo-ternary phase diagrams were constructed for the various microemulsion formulations which were prepared using glyceryl monooleate, oleic acid, ethyl oleate, or isopropyl myristate as the oily phase; a mixture of Tween 20®, Labrasol®, or Span 20® with HCO-40® (1:1 ratio) as surfactants; and Transcutol® as a cosurfactant. Oil-in-water microemulsions were selected to incorporate 2% w/w silymarin. After six heating-cooling cycles, physical appearances of all microemulsions were unchanged and no drug precipitation occurred. Chemical stability studies showed that microemulsion containing Labrasol® and isopropyl myristate stored at 40°C for 6 months showed the highest silybin remaining among others. The silybin remainings depended on the type of surfactant and were sequenced in the order of: Labrasol® > Tween 20® > Span 20®. In vitro release studies showed prolonged release for microemulsions when compared to silymarin solution. All release profiles showed the best fits with Higuchi kinetics. Non-occlusive in vitro skin permeation studies showed absence of transdermal delivery of silybin. The percentages of silybin in skin extracts were not significantly different among the different formulations (p > 0.05). Nevertheless, some silybin was detected in the receiver fluid when performing occlusive experiments. Microemulsions containing Labrasol® also were found to enhance silymarin solubility. Other drug delivery systems with occlusive effect could be further developed for dermal delivery of silymarin. PMID:22350738
Full Text Available Renad Alyautdin,1 Igor Khalin,2 Mohd Ismail Nafeeza,1 Muhammad Huzaimi Haron,1 Dmitry Kuznetsov31Faculty of Medicine, Universiti Teknologi MARA (UiTM, Sungai Buloh, Selangor, Malaysia; 2Faculty of Medicine and Defence Health, National Defence University of Malaysia (NDUM, Kuala Lumpur, Malaysia; 3Department of Medicinal Nanobiotechnologies, N. I. Pirogoff Russian State Medical University, Moscow, RussiaAbstract: The protective properties of the blood–brain barrier (BBB are conferred by the intricate architecture of its endothelium coupled with multiple specific transport systems expressed on the surface of endothelial cells (ECs in the brain's vasculature. When the stringent control of the BBB is disrupted, such as following EC damage, substances that are safe for peripheral tissues but toxic to neurons have easier access to the central nervous system (CNS. As a consequence, CNS disorders, including degenerative diseases, can occur independently of an individual's age. Although the BBB is crucial in regulating the biochemical environment that is essential for maintaining neuronal integrity, it limits drug delivery to the CNS. This makes it difficult to deliver beneficial drugs across the BBB while preventing the passage of potential neurotoxins. Available options include transport of drugs across the ECs through traversing occludins and claudins in the tight junctions or by attaching drugs to one of the existing transport systems. Either way, access must specifically allow only the passage of a particular drug. In general, the BBB allows small molecules to enter the CNS; however, most drugs with the potential to treat neurological disorders other than infections have large structures. Several mechanisms, such as modifications of the built-in pumping-out system of drugs and utilization of nanocarriers and liposomes, are among the drug-delivery systems that have been tested; however, each has its limitations and constraints. This review
Arati N Ranade
Full Text Available Usual treatment for Helicobacter pylori-induced peptic ulcer includes a 14-day "triple therapy" of two antibiotics and a proton pump inhibitor. However, the current therapy has side-effects like stomach upset, non-compliance, incomplete absorption of drug and antibiotic resistance. To overcome these limitations, there is a need to suggest an alternative therapy. The best possible alternative is to deliver herbal constituents. The purpose of the present study was to optimize the efficacy of herbal constituents by applying the concept of a novel drug delivery system. The present investigation is designed to deliver and retain two herbal constituents in the stomach for better action against gastric ulcers. The objective was to develop a bilayer floating tablet of monoammonium glycerrhizin and Aloe vera gel powder through rational combination of excipients to give the lowest possible lag time with maximum drug release in 7 h. Formulation OF2 containing hydroxy propyl methyl cellulose E5, crospovidone and effervescent agents in the ratio 1:2 gave 98% drug release with desired floating properties. Pharmacodynamic studies in rats showed that the combination of monoammonium glycerrhizin and Aloe vera gave 99% ulcer inhibition in comparison with 51% ulcer inhibition in the group administered with monoammonium glycerrhizin alone. X-ray studies in rabbits proved the gastroretention of the tablet for more than 6 h. This suggests relevance of NDDS in delivery of herbal constituents in the treatment of gastric ulcer.
Dito, Scott J.
The Independent System Health Management-Autonomous Control (ISHM-AC) application development for cryogenic delivery systems is intended to create an expert system that will require minimal operator involvement and ultimately allow for complete autonomy when fueling a space vehicle in the time prior to launch. The G2-Autonomous Control project is the development of a model, simulation, and ultimately a working application that will control and monitor the cryogenic fluid delivery to a rocket for testing purposes. To develop this application, the project is using the programming language/environment Gensym G2. The environment is an all-inclusive application that allows development, testing, modeling, and finally operation of the unique application through graphical and programmatic methods. We have learned G2 through training classes and subsequent application development, and are now in the process of building the application that will soon be used to test on cryogenic loading equipment here at the Kennedy Space Center Cryogenics Test Laboratory (CTL). The G2 ISHM-AC application will bring with it a safer and more efficient propellant loading system for the future launches at Kennedy Space Center and eventually mobile launches from all over the world.
Microfluidic drug delivery systems consisting of a drug reservoir and microfluidic channels have shown the possibility of simple and robust modulation of drug release rate. However, the difficulty of loading a small quantity of drug into drug reservoirs at a micro-scale limited further development of such systems. Electrohydrodynamic (EHD) printing was employed to fill micro-reservoirs with controlled amount of drugs in the range of a few hundreds of picograms to tens of micrograms with spatial resolution of as small as 20 µm. Unlike most EHD systems, this system was configured in combination with an inverted microscope that allows in situ targeting of drug loading at micrometer scale accuracy. Methylene blue and rhodamine B were used as model drugs in distilled water, isopropanol and a polymer solution of a biodegradable polymer and dimethyl sulfoxide (DMSO). Also tetracycline-HCl/DI water was used as actual drug ink. The optimal parameters of EHD printing to load an extremely small quantity of drug into microscale drug reservoirs were investigated by changing pumping rates, the strength of an electric field and drug concentration. This targeted EHD technique was used to load drugs into the microreservoirs of PDMS microfluidic drug delivery devices and their drug release performance was demonstrated in vitro. (paper)
Full Text Available Bioadhesion is an interfacial phenomenon in which two materials, at least one of which is biological, are held together by means of interfacial forces. When the associated biological system is mucous, it is called mucoadhesion. This property of certain polymeric systems have got place in the drug delivery research in order to prolong contact time in the various mucosal route of drug administration, as the ability to maintain a delivery system at a particular location for an extended period of time has a great appeal for both local action as well as systemic drug bioavailability. A complete and comprehensive theory that can predict adhesion based on the chemical and/or physical nature of a polymer is not yet available. Several theories have been proposed to explain the fundamental mechanisms of adhesion such as glues, adhesives, and paints, have been adopted to study the mucoadhesion. Mucoadhesion is a complex process and numerous theories have been presented to explain the mechanisms involved. These theories include mechanical-interlocking, electrostatic, diffusion–interpenetration, adsorption and fracture processes. They are Electronic theory, Adsorption theory, Wetting theory, Diffusion theory, Fracture theory. The objective of the study is to explain the different mechanisms involved in mucoadhesion and various factors affecting mucoadhesion.
Anthony N. Ilukwe
Full Text Available Retrieving learning material from the internet is a tedious process that has begged for a solution to filter out of the cluster of data and irrelevant material on the internet and deliver material that is relevant to a specific user. The Hybrid Search and Delivery of Learning Objects (HSDLO system, put forward in this study, facilitates the personalized search and delivery of such learning material from the internet. The system combines a number of mechanisms to perform this: Keyword‐based search, concept‐based search and personalization. The keyword-and concept-based search methods are responsible for establishing the relevance of each learning material retrieved from the web. The system presented in this study builds upon work done in the previous iteration by additional functionality; further decoupling the subsystems to improve modularity; perfection of the personalization subsystem; and a redesign of the user interface to a simpler form with Web2.0 sensibilities. Additionally, the personalization subsystem is substantially extended, allowing for a learner to have a profile active within the system during a session in which he or she is logged in and following a search, for the profile to be adapted and stored in memory for subsequent sessions. This functionality has been tested and successfully evaluated.
Full Text Available Amphotericin B is a polyene antifungal antibiotic belonging to Class IV of Biopharmaceutics Classification System which is not absorbed from the gastrointestinal tract after oral administration. The aim of this research work was to develop a self-emulsifying drug delivery system (SEDDS of amphotericin B and to evaluate the dissolution and permeability of amphotericin B from the formulation. The solubility of amphotericin B in various oils, surfactants and cosurfactants was determined. Various SEDDS formulations were prepared with varying amounts of oil, surfactant and co-surfactant. Evaluation parameters for formulation optimization were drug content, self-emulsification, droplet size analysis, and precipitation studies. In vitro dissolution was studied in comparison to the pure drug. Permeability was studied using non-everted intestinal sac method. The optimized formulation consisted of glycerol mono-oleate (10%, w/w, tween 80 (36%, w/w, polyethylene glycol 400 (27%, w/w, and propylene glycol (27%, w/w with a drug content of about 8 mg per ml. The self-emulsifying formulation showed 100% dissolution within 30 minutes whereas the pure drug exhibited a very poor rate of dissolution. In vitro intestinal permeability was studied by noneverted intestinal sac method using rat intestine. The self-emulsifying formulation showed 100% drug permeation within 30 minutes compared to negligible permeation from the drug suspension. The study demonstrates that SEDDS approach may be useful for enhancement of dissolution and intestinal permeation of amphotericin B belonging to class IV of Biopharmaceutic Classification System.
Ma, Ping; Mumper, Russell J
Paclitaxel is one of the most effective chemotherapeutic drugs ever developed and is active against a broad range of cancers, such as lung, ovarian, and breast cancers. Due to its low water solubility, paclitaxel is formulated in a mixture of Cremophor EL and dehydrated ethanol (50:50, v/v) a combination known as Taxol. However, Taxol has some severe side effects related to Cremophor EL and ethanol. Therefore, there is an urgent need for the development of alternative Taxol formulations. The encapsulation of paclitaxel in biodegradable and non-toxic nano-delivery systems can protect the drug from degradation during circulation and in-turn protect the body from toxic side effects of the drug thereby lowering its toxicity, increasing its circulation half-life, exhibiting improved pharmacokinetic profiles, and demonstrating better patient compliance. Also, nanoparticle-based delivery systems can take advantage of the enhanced permeability and retention (EPR) effect for passive tumor targeting, therefore, they are promising carriers to improve the therapeutic index and decrease the side effects of paclitaxel. To date, paclitaxel albumin-bound nanoparticles (Abraxane®) have been approved by the FDA for the treatment of metastatic breast cancer and non-small cell lung cancer (NSCLC). In addition, there are a number of novel paclitaxel nanoparticle formulations in clinical trials. In this comprehensive review, several types of developed paclitaxel nano-delivery systems will be covered and discussed, such as polymeric nanoparticles, lipid-based formulations, polymer conjugates, inorganic nanoparticles, carbon nanotubes, nanocrystals, and cyclodextrin nanoparticles. PMID:24163786
Simalango, Mikael Fernandus
Advances in web technologies have driven massive content uploads and requests that can be identified by the increased usage of multimedia web and social web services. This situation enforces the content providers to scale their infrastructure in order to cope with the extra provisioning of network traffic, storage and other resources. Since the complexity and cost factors in scaling the infrastructure exist, we propose a novel solution for providing and delivering contents to clients by introducing a brokered collaborative content delivery system. The architectural design of this system leverages content redundancy and content distribution mechanisms in other content providers to deliver contents to the clients. With the recent emergence of cloud computing, we show that this system can also be adopted to run on the cloud. In this paper, we focus on a brokering scheme to mediate user requests to the most appropriate content provider based on a ranking system. The architecture provides a novel Global Rank Value...
The locomotor being built by RedZone Robotics is designed to serve as a remote tool delivery (RID) system for waste retrieval, tank cleaning, viewing, and inspection inside the high-level waste tanks 8D-1 and 8D-2 at West Valley Nuclear Services (WVNS). The RTD systm is to be deployed through a tank riser. The locomotor portion of the RTD system is designed to be inserted into the tank and is to be capable of moving around the tank by supporting itself and moving on the tank internal structural columns. The locomotor will serve as a mounting platform for a dexterous manipulator arm. The complete RTD system consists of the locomotor, dexterous manipulator arm, cameras, lights, cables, hoses, cable/hose management system, power supply, and operator control station.
Baker, J J
The paradigm shift toward managed care is fueling new cost-finding demands. More sophisticated methods are emerging to meet these demands. Foremost among the new methods is activity-based costing (ABC). ABC is designed to eliminate cross-subsidies between products or services. Because costs are traced by activities across departments and cost centers, costs can also be traced by activities across integrated delivery systems (IDSs). The methodology makes ABC very applicable to combinations of providers including chains, affiliated groups, and IDS participants. PMID:8820298
Parker, B.; Anerella, M.; Escallier, J.; He, P.; Jain, A.; Marone, A.; /Brookhaven; Nosochkov, Y.; Seryi, Andrei; /SLAC
The ILC Beam Delivery System (BDS) uses a variety of superconducting magnets to maximize luminosity and minimize background. Compact final focus quadrupoles with multifunction correction coils focus incoming beams to few nanometer spot sizes while focusing outgoing disrupted beams into a separate extraction beam line. Anti-solenoids mitigate effects from overlapping focusing and the detector solenoid field. Far from the interaction point (IP) strong octupoles help minimize IP backgrounds. A low-field but very large aperture dipole is integrated with the detector solenoid to reduce backgrounds from beamstrahlung pairs generated at the IP. Physics requirements and magnetic design solutions for the BDS superconducting magnets are reviewed in this paper.
Garcia, H; Inntjore Levinsen, Y; Latina, A; Tomas, R; Snuverink, J
Tuning the Compact Linear Collider (CLIC) BeamDelivery System (BDS), and in particular the Final Focus (FF), is a challenging task. In simulations without misalignments, the goal is to reach 120%o f the nominal luminosity target, in order to allow for 10% loss due to static imperfections, and another 10% loss from dynamic imperfections. Various approaches have been considered to correct the magnet misalignments, including 1-1 correction, Dispersion Free Steering (DFS), and several minimization methods utilizing multipole movers. In this paper we report on the recent advancements towards a feasible tuning approach that reaches the required luminosity target.
Norgaard Jensen, L.; Christrup, Lona Louring; Menger, N.;
Chewing gum and lozenges were evaluated as delivery systems for noscapine with the aim of developing improved antitussive preparations. The formulations studied were prepared with both the water-soluble hydrochloride salt of noscapine and with the poorly soluble embonate salt and noscapine free...... base. The release characteristics of the preparations were evaluated both in vitro and in vivo, and their taste properties examined. Only the formulations containing noscapine base were without any appreciable taste. Chewing gum containing this compound showed, however, a low level of drug release both...
Baker, J J
The paradigm shift toward managed care is fueling new cost-finding demands. More sophisticated methods are emerging to meet these demands. Foremost among the new methods is activity-based costing (ABC). ABC is designed to eliminate cross-subsidies between products or services. Because costs are traced by activities across departments and cost centers, costs can also be traced by activities across integrated delivery systems (IDSs). The methodology makes ABC very applicable to combinations of providers including chains, affiliated groups, and IDS participants.
Bhosale, UV; Kusum, Devi V; Jain, N
Acyclovir is an antiviral drug used for the treatment of herpes simplex virus infections, with an oral bioavailability of only 10–20% [limiting absorption in gastrointestinal tract to duodenum and jejunum] and half-life of about 3 h, and is soluble only at acidic pH (pKa 2.27). Mucoadhesive polymeric nanodrug delivery systems of acyclovir have been designed and optimized using 23 full factorial design. Poly (lactic-co-glycolic acid) (PLGA) (50:50) was used as the polymer along with polycarbop...
Analytical characteristics and application of novel chitosan coated magnetic nanoparticles as an efficient drug delivery system for ciprofloxacin. Enhanced drug release kinetics by low-frequency ultrasounds.
Kariminia, Samira; Shamsipur, Ali; Shamsipur, Mojtaba
A pH-responsive drug carrier based on chitosan coated iron oxide nanoparticles (CS-Fe3O4) for prolonged antibiotic release in a controlled manner is reported. As an antibiotic drug model, ciprofloxacin was loaded onto the nanocarrier via H-bonding interactions. The nanoparticles were characterized using scanning electron microscopy, X-ray diffraction, energy-dispersive X-ray spectroscopy, photon correlation spectroscopy and Fourier transform infrared spectroscopy. The particle size of CS-Fe3O4 nanoparticles were found to lie in the range of 30-80nm. The analytical characteristics of the designed system were thoroughly investigated. The in vitro drug loading at pH 4.8 and release kinetics at pH 7.4 studies revealed that the drug delivery system can take 99% of ciprofloxacin load and quantitatively release the drug over a sustained period of 5 days. The release kinetics study indicated that the system follows a zero order kinetics via a diffusion-controlled mechanism. These results indicated that CS-Fe3O4 nanoparticles have the potential for use as controlled antibiotic delivery systems through oral administration by avoiding the drug release in the highly acidic gastric fluid region of the stomach. Furthermore, the ability of low-frequency ultrasound in fast release of the encapsulated drug in less than 60min from the CS-Fe3O4 nanoparticles in a controlled manner was confirmed. PMID:27497305
Loschenov, Victor B.; Taraz, Majid
Methods of optical diagnostics and methods of photodynamic therapy are actively used in medico-biological researches. The system for delivery of optical radiation is one of the key methods in these researches. Usually these systems use flexible optical fibers with diameters from 200 to 1000 micron. Two types of systems for delivery are subdivided, first for diagnostic researches, second for therapeutic procedures. Existing diagnostic catheters, which have most widely applied in medicine, have bifurcated with diameter of the tip equal 1.8 mm. These devices, which are called fiber-optical catheters, satisfy the majority endoscopes researches. However, till now the problem of optical-diagnostics inside tissue is not soled. Especially it is important at diagnostics of a mammary gland, livers, thyroid glands tumor, tumor of a brain and some other studies connected with punctures. In these cases, it is necessary that diameter of fiber-optical catheters be less than one millimeter. This work is devoted to the development of these catheters. Also in clinical procedures such as photodynamic therapy (PDT) and interstitial laser photocoagulation (ILP), cylindrical light diffusing tips are rapidly becoming a popular device for the administration of the desired light dose for the illumination of hollow organs, such as bronchus, trachea and oesophagus. This work is devoted to the development of these catheters.
Full Text Available Transdermal route of drug delivery system has received a great attention in pharmaceutical research and it has already proved its superiority in various respects than oral route, which has a number of problems in drug delivery system. However, the permeation of hydrophilic ioniazable species of drug always has been denied by the intrinsic barrier or stratum corneum for providing local or systemic actions. Transferosomes are ultra deformable vesicles, elastic in nature, which can squeeze itself through a pore and it is more advantageous than the conventional liposome due to its high elasticity, which offers its penetration through narrow constriction without measurable loss. The high permeability of transferosome across the skin also depends on its deformability and intermediate attachment sites for membrane fusion due presence of ripples in vesicles surface. Its infrastructure posses both hydrophilic and hydrophobic moieties together and it can entrap both type of drug. They can act as a carrier for low as well as high molecular weight drugs e.g., analgesics, anesthetics, corticosteroids, sex hormones, anticancer drugs, insulin, gap junction proteins, albumin, etc.
Castro, S. L.; Ott, C. M.; Douglas, G. L.
The addition of probiotic bacteria to the space food system is expected to confer immunostimulatory benefits on crewmembers during spaceflight, counteracting the immune dysregulation that has been documented in spaceflight. Specifically, the probiotic Lactobacillus acidophilus has been shown to promote health benefits including antagonism towards and inhibition of virulence related gene expression in pathogens, mucosal stimulation of immune cells, and a reduction in the occurrence and duration of cold and flu-like symptoms. The optimum delivery system for probiotics has not been determined for spaceflight, where the food system is shelf stable and the lack of refrigeration prevents the use of traditional dairy delivery methods. This work proposes to determine whether L. acidophilus is more viable, and therefore more likely to confer immune benefit, when delivered in a capsule form or when delivered in nonfat dry milk powder with a resuscitation opportunity upon rehydration, following 0, 4, and 8 months of storage at -80degC, 4degC, and 22degC, and both prior to and after challenge with simulated gastric and intestinal juices. We hypothesize that the low moisture neutral dairy matrix provided by the nonfat dry milk, and the rehydration step prior to consumption, will extend probiotic viability and stress tolerance compared to a capsule during potential storage conditions in spaceflight and in simulated digestion conditions.
Giri, Tapan Kumar; Thakur, Deepa; Alexander, Amit; Ajazuddin; Badwaik, Hemant; Tripathi, Dulal Krishna
Alginate is a non-toxic, biocompatible and biodegradable natural polymer with a number of peculiar physicochemical properties for which it has wide applications in drug delivery and cell delivery systems. Hydrogel formation can be obtained by interactions of anionic alginates with multivalent inorganic cations by simple ionotropic gelation method. Hydrophilic polymeric network of three dimensional cross linked structures of hydrogels absorb substantial amount of water or biological fluids. Among the numerous biomaterials used for hydrogel formation alginate has been and will continue to be one of the most important biomaterial. Therefore, in view of the vast literature support, we focus in this review on alginate - based hydrogel as drug delivery and cell delivery carriers for biomedical applications. Various properties of alginates, their hydrogels and also various techniques used for preparing alginate hydrogels have been reviewed. PMID:22998675
... Recommendations Pediatric Treatment Recommendations Inpatient Healthcare Professionals Community Pharmacists Continuing Education & Curriculum Opportunities Weighing in on Antibiotic Resistance Improving Prescribing Outpatient Antibiotic Stewardship Interventions That Work Systematic Reviews ...
Charlton, S T; Davis, S S; Illum, L
There is an increasing need for nasal drug delivery systems that could improve the efficiency of the direct nose to brain pathway especially for drugs for treatment of central nervous system disorders. Novel approaches that are able to combine active targeting of a formulation to the olfactory region with controlled release bioadhesive characteristics, for maintaining the drug on the absorption site are suggested. If necessary an absorption enhancer could be incorporated. Low methylated pectins have been shown to gel and be retained in the nasal cavity after deposition. Chitosan is known to be bioadhesive and also to work as an absorption enhancer. Consequently, two types of pectins, LM-5 and LM-12, together with chitosan G210, were selected for characterisation in terms of molecular weight, gelling ability and viscosity. Furthermore, studies on the in vitro release of model drugs from candidate formulations and the transport of drugs across MDCK1 cell monolayers in the presence of pectin and chitosan were also performed. Bioadhesive formulations providing controlled release with increased or decreased epithelial transport were developed. Due to their promising characteristics 3% LM-5, 1% LM-12 pectin and 1% chitosan G210 formulations were selected for further biological evaluation in animal models.
Crick, Colin R; Clausen-Thue, Victoria; Parkin, Ivan P
The hydrophobicity, robustness and anti-microbial properties of Sylgard 184 polymer films deposited via AACVD were optimised by using aerosol droplets from an atomiser delivery system, polymer coating substrates and the swell encapsulation of methylene blue. By using an atomiser deposition system (average droplet size 0.35 microm) rather than a misting aerosol system (45 microm) lead to a surface with smaller surface features, which improved hydrophobicity (water contact angle 165 degrees) in addition to increasing the films transparency from ca 10 to 65%. Pre-treating the substrates with the same Sylgard 184 elastomer lead to a highly consistent surface hydrophobicity and an increase in average water contact angle measured (169 degrees). This paper shows the first example of dye incorporation in a CVD derived polymer film-these films have potential as antimicrobial surfaces.
Janjic, Jelena M.; Berlec, Ales; Bagia, Christina; Liu, Lu S.; Jeric, Irenej; Gach, Michael; Janjic, Bratislav M.; Strukelj, Borut
Current treatment of inflammatory bowel disease (IBD) is largely symptomatic and consists of anti-inflammatory agents, immune-suppressives or antibiotics, whereby local luminal action is preferred to minimize systemic side-effects. Recently, anti-TNFα therapy has shown considerable success and is now being routinely used. Here we present a novel approach of using perfluorocarbon (PFC) nanoemulsion containing hydrogels (nanoemulgels) as imaging supported delivery systems for anti-TNF alpha probiotic delivery in IBD. To further facilitate image-guided therapy a food-grade lactic acid bacterium Lactococcus lactis capable of TNFα-binding was engineered to incorporate infrared fluorescent protein (IRFP). This modified bacteria was then incorporated into novel PFC nanoemulgels. The nanoemulgels presented here are designed to deliver locally anti-TNFα probiotic in the lower colon and rectum and provide dual imaging signature of gel delivery (MRI) across the rectum and lower colon and bacteria release (NIR). NIR imaging data in vitro demonstrates high IRFP expressing and TNFα-binding bacteria loading in the hydrogel and complete release in 3 hours. Stability tests indicate that gels remain stable for at least 14 days showing no significant change in droplet size, zeta potential and pH. Flow cytometry analyses demonstrate the NIRF expressing bacteria L. lactis binds TNFα in vitro upon release from the gels. Magnetic resonance and near-infrared imaging in vitro demonstrates homogeneity of hydrogels and the imaging capacity of the overall formulation.
Full Text Available Self-assembling multifunctional peptide was designed for gene delivery systems. The multifunctional peptide (MP consists of cellular penetrating peptide moiety (R8, matrix metalloproteinase-2 (MMP-2 specific sequence (GPLGV, pH-responsive moiety (H5, and hydrophobic moiety (palmitic acid (CR8GPLGVH5-Pal. MP was oxidized to form multifunctional peptide dimer (MPD by DMSO oxidation of thiols in terminal cysteine residues. MPD could condense pDNA successfully at a weight ratio of 5. MPD itself could self-assemble into submicron micelle particles via hydrophobic interaction, of which critical micelle concentration is about 0.01 mM. MPD showed concentration-dependent but low cytotoxicity in comparison with PEI25k. MPD polyplexes showed low transfection efficiency in HEK293 cells expressing low level of MMP-2 but high transfection efficiency in A549 and C2C12 cells expressing high level of MMP-2, meaning the enhanced transfection efficiency probably due to MMP-induced structural change of polyplexes. Bafilomycin A1-treated transfection results suggest that the transfection of MPD is mediated via endosomal escape by endosome buffering ability. These results show the potential of MPD for MMP-2 targeted gene delivery systems due to its multifunctionality.
Full Text Available Traditionally, drugs are released in an immediate or extended manner. A pulsatile drug release, where the drug is released rapidly after a well defined lag-time, could be advantageous for many drugs or therapies. As the pulsatile drug delivery achieve desired therapeutic effect and reducing side effect, so patient compliance can be obtained along with lowering dose frequency. These systems are designed according to the circadian rhythm of the body and the drug is released as a pulse. Diseases like asthma, peptic ulcers, cardiovascular ailments, arthritis and attention deficit syndrome in children and hypercholesterolemia can be cured by drugs, released by PDDS. Recent trends include Multiparticulate drug delivery systems that are especially suitable for achieving controlled or delayed release oral formulations with low risk of dose dumping, flexibility of blending to attain different release patterns as well as reproducible and short gastric residence time. Various methods and marketed technologies of PDDS such as Pulsincap TM, Diffucaps, CODAS, OROS and PULSYSTM are covered in this review.
Bansal, Shyam S; Goel, Mehak; Aqil, Farrukh; Vadhanam, Manicka V; Gupta, Ramesh C
Since ancient times, chemopreventive agents have been used to treat/prevent several diseases including cancer. They are found to elicit a spectrum of potent responses including anti-inflammatory, antioxidant, antiproliferative, anticarcinogenic, and antiangiogenic activity in various cell cultures and some animal studies. Research over the past 4 decades has shown that chemopreventives affect a number of proteins involved in various molecular pathways that regulate inflammatory and carcinogenic responses in a cell. Various enzymes, transcription factors, receptors, and adhesion proteins are also affected by chemopreventives. Although, these natural compounds have shown significant efficacy in cell culture studies, they elicited limited efficacy in various clinical studies. Their introduction into the clinical setting is hindered largely by their poor solubility, rapid metabolism, or a combination of both, ultimately resulting in poor bioavailability upon oral administration. Therefore, to circumvent these limitations and to ease their transition to clinics, alternate strategies should be explored. Drug delivery systems such as nanoparticles, liposomes, microemulsions, and polymeric implantable devices are emerging as one of the viable alternatives that have been shown to deliver therapeutic concentrations of various potent chemopreventives such as curcumin, ellagic acid, green tea polyphenols, and resveratrol into the systemic circulation. In this review article, we have attempted to provide a comprehensive outlook for these delivery approaches, using curcumin as a model agent, and discussed future strategies to enable the introduction of these highly potent chemopreventives into a physician's armamentarium. PMID:21546540
New and improved vaccines and delivery systems are increasingly being developed for prevention, treatment and diagnosis of human diseases. Prior to their use in humans, all new biological products must undergo pre-clinical evaluation. These pre-clinical studies are important not only to establish the biological properties of the material and to evaluate its possible risk to the public, but also to plan protocols for subsequent clinical trials from which safety and efficacy can be evaluated. For vaccines, evaluation in pre-clinical studies is particularly important as information gained may also contribute to identifying the optimum composition and formulation process and provide an opportunity to develop suitable indicator tests for quality control. Data from pre-clinical and laboratory evaluation studies, which continue during clinical studies, is used to support an application for marketing authorisation. Addition of a new adjuvant and exploration of new delivery systems for vaccines presents challenges to both manufacturers and regulatory authorities. Because no adjuvant is licensed as a medicinal product in its own right, but only as a component of a particular vaccine, pre-clinical and appropriate toxicology studies need to be designed on a case-by-case basis to evaluate the safety profile of the adjuvant and adjuvant/vaccine combination. Current regulatory requirements for the pharmaceutical and pre-clinical safety assessment of vaccines are insufficient and initiatives are in place to develop more specific guidelines for evaluation of adjuvants in vaccines.
Full Text Available During last decades, diphtheria has remained as a serious disease that still outbreaks and can occur worldwide. Recently, new vaccine delivery systems have been developed by using the biodegradable and biocompatible polymers such as alginate. Alginate nanoparticles as a carrier with adjuvant and prolong release properties that enhance the immunogenicity of vaccines. In this study diphtheria toxoid loaded nanoparticles were prepared by ionic gelation technique and characterized with respect to size, zeta potential, morphology, encapsulation efficiency, release profile, and immunogenicity. Appropriate parameters (calcium chloride and sodium alginate concentration, homogenization rate and homogenization time redounded to the formation of suitable nanoparticles with a mean diameter of 70±0.5 nm. The loading studies of the nanoparticles resulted in high loading capacities (>90% and subsequent release studies showed prolong profile. The stability and antigenicity of toxoid were evaluated by sodium dodecyl sulfate polyacrylamide gel electrophoresis and ouchterlony test and proved that the encapsulation process did not affect the antigenic integrity and activity. Guinea pigs immunized with the diphtheria toxoid-loaded alginate nanoparticles showed highest humoral immune response than conventional vaccine. It is concluded that, with regard to the desirable properties of nanoparticles and high immunogenicity, alginate nanoparticles could be considered as a new promising vaccine delivery and adjuvant system.
Cerqueira-Coutinho, Cristal; Dos Santos, Elisabete P; Mansur, Claudia Regina E
Nanosystems used in the pharmaceutical field aim to guarantee a controlled release and efficacy boost with dose reduction of the drug. The same active ingredient could be vehiculated in different concentrations in distinct nanosystems. Among these nanostructures, the vesicular ones present a versatile delivery system that could be applied to encapsulate lipophilic, amphiphilic, and hydrophilic compounds. Liposomes are the most well-known vesicular nanosystems; however, there are others, such as niosomes, that are composed of nonionic surfactants that are polymeric or conventional. Niosomes could be prepared using the thin film hydration method, in which the active ingredient is solubilized in organic solvent with the surfactant or in aqueous solution depending on its polarity. In addition, co-surfactants could be used to improve stabilization and vesicle integrity because they occupy regions in the interface where the mainly surfactant could not reach. Vesicular nanosystems could be characterized by different techniques, such as microscopy, dynamic light scattering, nuclear magnetic resonance, and others. These nanostructures could be applied to drugs (administered by different routes) or to gene and cosmetic delivery systems. PMID:27651102
Full Text Available The aim of the present work to study the preformulation parameters for Transdermal drug delivery system. The objective of Preformulation study is to generic information useful to the formulater in developing stable and bioavailable dosage form. The use of Preformulation parameter maximizes the chances in formulation an acceptable, safe, efficacious and stable product and at the same time provide the basis for optimization of the drug product quality. Administration of conventional tablets of simvastatin has been reported to exhibit fluctuations in plasma drug levels, resulting either in manifestation of side effects or reduction in drug concentration at the receptor sites also, the maintenance of a constant plasma concentration of a cardiovascular drug is important in ensuring the desired therapeutic response, again since the half life of simvastatin is 3 hours hence multiple doses of the drug are needed to maintain a constant plasma concentration for a good therapeutic response, and improve patient compliance, hence the objective of the study was made to develop controlled release TDDS of simvastatin using polymer like HPMC and Carbopol, which will controlled the release of drug, increasing the bioavailability of the drug and thus decreasing the dosing frequency of the drug. The Preformulation studies were carried out in terms of testa for identification (physical appearance, melting point, and uv spectrophotometer, solubility profile, determination of partition coefficient and quantitative estimation of drug. All the observation and results showed that the simvastatin could serve as suitable candidate for Transdermal drug delivery system that may improve the bioavailability.
Liu, Dong; Yang, Fang; Xiong, Fei; Gu, Ning
With the unprecedented progresses of biomedical nanotechnology during the past few decades, conventional drug delivery systems (DDSs) have been involved into smart DDSs with stimuli-responsive characteristics. Benefiting from the response to specific internal or external triggers, those well-defined nanoplatforms can increase the drug targeting efficacy, in the meantime, reduce side effects/toxicities of payloads, which are key factors for improving patient compliance. In academic field, variety of smart DDSs have been abundantly demonstrated for various intriguing systems, such as stimuli-responsive polymeric nanoparticles, liposomes, metals/metal oxides, and exosomes. However, these nanoplatforms are lack of standardized manufacturing method, toxicity assessment experience, and clear relevance between the pre-clinical and clinical studies, resulting in the huge difficulties to obtain regulatory and ethics approval. Therefore, such relatively complex stimulus-sensitive nano-DDSs are not currently approved for clinical use. In this review, we highlight the recent advances of smart nanoplatforms for targeting drug delivery. Furthermore, the clinical translation obstacles faced by these smart nanoplatforms have been reviewed and discussed. We also present the future directions and perspectives of stimuli-sensitive DDS in clinical applications. PMID:27375781
Ordikhani, Farideh; Dehghani, Mehdi; Simchi, Arash
In this study, chitosan-Laponite nanocomposite coatings with bone regenerative potential and controlled drug-release capacity are prepared by electrophoretic deposition technique. The controlled release of a glycopeptide drug, i.e. vancomycin, is attained by the intercalation of the polymer and drug macromolecules into silicate galleries. Fourier-transform infrared spectrometry reveals electrostatic interactions between the charged structure of clay and the amine and hydroxyl groups of chitosan and vancomycin, leading to a complex positively-charged system with high electrophoretic mobility. By applying electric field the charged particles are deposited on the surface of titanium foils and uniform chitosan films containing 25-55 wt% Laponite and 937-1655 µg/cm(2) vancomycin are obtained. Nanocomposite films exhibit improved cell attachment with higher cell viability. Alkaline phosphatase assay reveals enhanced cell proliferation due the gradual dissolution of Laponite particles into the culture medium. In-vitro drug-release studies show lower release rate through a longer period for the nanocomposite compared to pristine chitosan. PMID:26507202
Full Text Available Oral route of drug administration is considered as the safest and easiest route of drug administration. Control release drug delivery system is the emerging trend in the pharmaceuticals and the oral route is most suitable for such kind of drug delivery system. Oral route is more convenient for It all age group including both pediatric and geriatrics. There are various systems which are adopted to deliver drug in a controlled manner to different target sites through oral route. It includes diffusion controlled drug delivery systems; dissolution controlled drug delivery systems, osmotically controlled drug delivery systems, ion-exchange controlled drug delivery systems, hydrodynamically balanced systems, multi-Particulate drug delivery systems and microencapsulated drug delivery system. The systems are formulated using different natural, semi-synthetic and synthetic polymers. The purpose of the review is to provide information about the orally controlled drug delivery system, polymers which are used to formulate these systems and characterizations of one of the most convenient dosage form which is the tablets.
Garvendra S Rathore
Full Text Available In the present study, we developed and evaluated the controlled porosity osmotic pump (CPOP based drug delivery system of sparingly water soluble drug atenolol (ATL. We selected target release profile and optimized different variables to help us achieve this. Formulation variables, such as, the levels of solubility enhancer (0-15% w/w of drug, ratio of the drug to the osmogents, coat thickness of the semipermeable membrane (SPM and level of pore former (0-20% w/w of polymer were found to effect the drug release from the developed formulations. Cellulose acetate (CA 398-10 was used as the semipermeable membrane containing polyethylene glycol 400 as the Cplasticizer. ATL release was directly proportional to the level of the solubility enhancer, osmotic pressure generated by osmotic agent and level of pore former; however, was inversely proportional to the coat thickness of SPM. Drug release from developed formulations was independent of the pH and agitation intensities of release media. Burst strength of the exhausted shells decreased with increase in the level of pore former. The optimized formulations were subjected to stability studies as per International Conference on Harmonisation (ICH guidelines, and formulations were found to be stable after 3 months study. Steady-state plasma levels of drug were predicted by the method of superposition.
Full Text Available For their optimal use in distance education (DE, online educational applications need to be integrated within a comprehensive course management system (CMS. Such systems are server-based software that supports the development, delivery, administration, and evaluation of online learning environments. The selection of an appropriate CMS should be considered from the multiple perspectives of the student, the course developer, the course instructor/ tutor, the technical support staff, and the DE institution’s administration. The current evaluation of CMS packages was conducted by a team of individuals with experience and contacts in relation to each of these DE user types. The report compares a series of CMS packages in terms of their range of features, and in relation to their satisfaction of international online education standards.
Aravindaram, Kandan; Yang, Ning Sun
Gene-based immunization with transgenic DNA vectors expressing tumor-associated antigens (TAA), cytokines, or chemokines, alone or in combination, provides an attractive approach to increase the cytotoxic T cell immunity against various cancer diseases. With this consideration, particle-mediated or gene gun technology has been developed as a nonviral method for gene transfer into various mammalian tissues. It has been shown to induce both humoral and cell-mediated immune responses in both small and large experimental animals. A broad range of somatic cell types, including primary cultures and established cell lines, has been successfully transfected ex vivo or in vitro by gene gun technology, either as suspension or adherent cultures. Here, we show that protocols and techniques for use in gene gun-mediated transgene delivery system for skin vaccination against melanoma using tumor-associated antigen (TAA) human gpl00 and reporter gene assays as experimental systems.
Stateless geographic routing provides relatively good performance at a fixed overhead, which is typically much lower than conventional routing protocols such as AODV. However, the performance of geographic routing is impacted by physical voids, and localization errors. Accordingly, virtual coordinate systems (VCS) were proposed as an alternative approach that is resilient to localization errors and that naturally routes around physical voids. However, VCS also faces virtual anomalies, causing their performance to trail geographic routing. In existing VCS routing protocols, there is a lack of an effective stateless and delivery guaranteed complementary routing algorithm that can be used to traverse voids. Most proposed solutions use variants of flooding or blind searching when a void is encountered. In this paper, we propose a spanning-path virtual coordinate system which can be used as a complete routing algorithm or as the complementary algorithm to greedy forwarding that is invoked when voids are encountere...
A targeted delivery system based on the polymeric nanoparticles as a drug carrier represents a marvelous avenue for cancer therapy. The pivotal characteristics of this system include biodegradability, biocompatibility, non-toxicity, prolonged circulation and a wide payload spectrum of a therapeutic agent. Other outstanding features are their distinctive size and shape properties for tissue penetration via an active and passive targeting, specific cellular/subcellular trafficking pathways and facile control of cargo release by sophisticated material engineering. In this review, the current implications of encapsulation of anticancer agents within polyhydroxyalkanoates, poly-(lactic-co-glycolic acid) and cyclodextrin based nanoparticles to precisely target the tumor site, i.e., cell, tissue and organ are highlighted. Furthermore, the promising perspectives in this emerging field are discussed. PMID:26706565
Wahap, N. A.; Ismail, N. M.; Nor, N. M.; Ahmad, N.; Omar, M. F.; Termizi, A. A. A.; Zainal, D.; Noordin, N. M.; Mansor, S.
Spatial information has introduced a new sense of urgency for a better understanding of the public needs in term of what, when and where they need services and through which devices, platform or physical locations they need them. The objective of this project is to value- add existing license management process for business premises which comes under the responsibility of Local Authority (PBT). Manipulation of geospatial and tracing technology via mobile platform allows enforcement officers to work in real-time, use a standardized system, improve service delivery, and optimize operation management. This paper will augment the scope and capabilities of proposed concept namely, Smart Licensing/Enforcement Management (SLEm). It will review the current licensing and enforcement practice of selected PBT in comparison to the enhanced method. As a result, the new enhanced system is expected to offer a total solution for licensing/enforcement management whilst increasing efficiency and transparency for smart city management and governance.
A.P. Patil*, A.A. Tagalpallewar, G.M. Rasve, A.V. Bendre, P.G. Khapekar
Full Text Available The ophthalmic in-situ gels now days proved an palpable sustained drug delivery in various eye diseases. The formulation of in-situ gels for eye which carries the advantages like easy for administration, reduces frequency of dose and improves patient compliance. The formation of in-situ gels depends on phase transition system or sol-gel transition system. The formulation approaches like temperature intonation, pH change and presence of ions from which the drug gets released in a sustained and controlled manner are utilised for in-situ gels. Various polymers that are used for the formulation of in-situ gels include chitosan, Pluronic F-127, poly-caprolactone, gellan gum, alginic acid, xyloglucan, pectin etc.
Chen, Ming; Liu, Xiangli; Fahr, Alfred
The aim of the present research is to evaluate the skin delivery capabilities of different vesicular systems, including conventional liposomes (CL), Tween 80-based deformable liposomes (DL), invasomes (INS) and ethosomes bearing ferulic acid (FA) being an antioxidant exhibiting a wide range of therapeutic effects against various diseases. All of the test formulations were characterized for particle size distribution, zeta-potential, vesicular shape and surface morphology, in vitro human skin permeation and skin deposition. Dynamic Light Scattering (DLS) and Transmission Electron Microscopy (TEM) defined that all of liposomal vesicles were almost spherical, displaying unilamellar structures with low polydispersity (PDI ethosomal system containing 18.0 mg/ml of ferulic acid with an significantly (P ethosomes are promising vesicular carriers for delivering ferulic acid into or across the skin. PMID:21329050
Terry, Treniece La'shay
Progress in the fields of molecular biology and genomics has provided great insight into the pathogenesis of disease and the defense mechanisms of the immune system. This knowledge has lead to the classification of an array of abnormal genes, for which, treatment relies on cellular expression of proteins. The utility of DNA-based vaccines hold great promise for the treatment of genetically based and infectious diseases, which ranges from hemophilia, cystic fibrosis, and HIV. Synthetic delivery systems consisting of cationic polymers, such as polyethylenimine (PEI), are capable of condensing DNA into compact structures, maximizing cellular uptake of DNA and yielding high levels of protein expression. To date, short term expression is a major obstacle in the development of gene therapies and has halted their expansion in clinical applications. This study intends to develop a sustained release vaccine delivery system using PLA-PEG block copolymers encapsulating PEI:DNA polyplexes. To enhance the effectiveness of such DNA-based vaccines, resident antigen presenting cells, macrophages and dendritic cells, will be targeted within the alveoli regions of the lungs. Porous microspheres will be engineered with aerodynamic properties capable of achieving deep lung deposition. A fabrication technique using concentric nozzles will be developed to produce porous microspheres. It was observed that modifications in the dispersed to continuous phase ratios have the largest influence on particle size distributions, release rates and encapsulation efficiency which ranged form 80--95% with fourteen days of release. Amphiphilic block copolymers were also used to fabricate porous microspheres. The confirmation of PEG within the biodegradable polymer backbone was found to have a tremendous impact on the microsphere morphology and encapsulation efficiency which varied from 50--90%. Porous microspheres were capable of providing sustained gene expression when tested in vitro using the
Edward T. Maggio
Full Text Available Intranasal drug delivery is becoming an increasingly important form of drug administration for chronic and chronic-intermittent diseases. Important new applications in development include drugs for diabetes, osteoporosis, obesity, certain types of convulsive disorders, migraine headaches, symptomatic pain relief, nausea, and anxiety, among others. Transmucosal absorption across the nasal mucosa is generally limited to molecules under 1,000 Da in size. Systemic delivery of molecules larger than this requires formulation with a suitable transmucosal absorption enhancer. More than one hundred potential transmucosal absorption enhancing excipients have been tested to date. Nearly all have failed to be practical due to poor effectiveness or unacceptable toxicity to mucosal tissue. Alkylsaccharides, cyclodextrins, and chitosan's have emerged as the leading candidates for potential broad clinical applications and are allowing development of convenient, patient-friendly, needle free formulations of small molecule drugs, as well as peptide and protein drugs that can be administered at home, at work, or in other public and private settings outside of the doctor’s office or hospital environment.
Full Text Available Targeted delivery of drugs to colon has the potential for local treatment of a variety of colonic diseases. The main objective of the study was to develop a multiparticulate system containing chitosan microspheres for the colon targeted delivery of ondansetron for the treatment of irritable bowel syndrome. This work combines pH-dependent solubility of eudragit S-100 polymers and microbial degradability of chitosan polymers. Chitosan microspheres containing ondansetron were prepared by emulsion cross linking method. The effect of process variables like chitosan concentration, drug-polymer ratio, emulsifier concentration and stirring speed were studied on particle size and entrapment efficiency of chitosan microspheres. In vitro drug release studies in simulated gastro intestinal fluids showed a burst drug release pattern in the initial hour necessitating microencapsulation around the chitosan microspheres. The optimized formulation was then subjected to microencapsulation with eudragit S-100 by solvent evaporation technique. The effect of different coat/core ratio on particle size, drug entrapment efficiency and in vitro drug release were studied. Formulation which contain 1:10 core/coat ratio released lesser amount of drug in the upper gastro intestinal conditions and so selected as best formulation and then subjected to in vitro drug release studies in presence of rat ceacal contents to assess biodegradability of chitosan microspheres in colon. In order to study the drug release mechanism in vitro drug release data was fitted into various kinetic models. Analysis of regression values suggested that the possible drug release mechanism was Peppas model.
Datz, David; Hallberg, Colleen; Harris, Kathy; Harrison, Lisa; Samples, Patience
Banner Health has long recognized the need to anticipate, beyond the immediate operational realities or even the annual budgeting projection exercises, the necessary workforce needs of the future. Thus, in 2011, Banner implemented a workforce planning model that included structures, processes, and tools for predicting workforce needs, with particular focus on identified critical systemwide practice areas. The model represents the incorporation of labor management tools and processes with more strategic, broad-view, long-term assessment and planning mechanisms. The sequential tying of the workforce planning lifecycle with the organization's strategy and financial planning process supports alignment of goals, objectives, and resource allocation. Collaboration among strategy, finance, human resources, and operations has provided us with the ability to identify critical position groups based on 3-year strategic priorities. By engaging leaders from across the organization, focusing on activities at facility, regional, and system levels, and building in mechanisms for accountability, we are now engaged in continuous evaluations of our delivery models, the competencies and preparations necessary for the staff to effectively function within those delivery models, and developing and implementing action plans designed to ensure adequate numbers of the staff whose competencies will be suited to the work expected of them.
Maria Victoria Maliandi
Full Text Available The continuous identification of molecular changes deregulating critical pathways in pancreatic tumor cells provides us with a large number of novel candidates to engineer gene-targeted approaches for pancreatic cancer treatment. Targets—both protein coding and non-coding—are being exploited in gene therapy to influence the deregulated pathways to facilitate cytotoxicity, enhance the immune response or sensitize to current treatments. Delivery vehicles based on viral or non-viral systems as well as cellular vectors with tumor homing characteristics are a critical part of the design of gene therapy strategies. The different behavior of tumoral versus non-tumoral cells inspires vector engineering with the generation of tumor selective products that can prevent potential toxic-associated effects. In the current review, a detailed analysis of the different targets, the delivery vectors, the preclinical approaches and a descriptive update on the conducted clinical trials are presented. Moreover, future possibilities in pancreatic cancer treatment by gene therapy strategies are discussed.
Full Text Available Ying-Zheng Zhao,1,3 Li-Na Du,2 Cui-Tao Lu,1 Yi-Guang Jin,2 Shu-Ping Ge3 1Wenzhou Medical College, Wenzhou City, Zhejiang Province, 2Department of Pharmaceutical Sciences, Beijing Institute of Radiation Medicine, Beijing, People’s Republic of China; 3St Christopher’s Hospital for Children/Drexel University College of Medicine, Philadelphia, PA, USA Abstract: Ultrasound is an important local stimulus for triggering drug release at the target tissue. Ultrasound-responsive drug delivery systems (URDDS have become an important research focus in targeted therapy. URDDS include many different formulations, such as microbubbles, nanobubbles, nanodroplets, liposomes, emulsions, and micelles. Drugs that can be loaded into URDDS include small molecules, biomacromolecules, and inorganic substances. Fields of clinical application include anticancer therapy, treatment of ischemic myocardium, induction of an immune response, cartilage tissue engineering, transdermal drug delivery, treatment of Huntington’s disease, thrombolysis, and disruption of the blood–brain barrier. This review focuses on recent advances in URDDS, and discusses their formulations, clinical application, and problems, as well as a perspective on their potential use in the future. Keywords: ultrasound, targeted therapy, clinical application
Nidhi Mishra; Narayan P Yadav; Jaya Gopal Meher; Priyam Sinha
Objective: To discuss the preparation, characterization, targeting and formulation aspect of phospholipids based drug delivery system i.e. Phyto-vesicles. Methods: The methods of phyto-vesicles preparation on R & D scale and different analytical techniques to characterize them have been discussed. Result: Phyto-vesicles are the advanced form of herbal drug delivery systems as its structure includes water soluble head and two fat soluble tails which act as an effective emulsifier. Conclusion: It is concluded that phytovesicular delivery system has improved pharmacokinetic and pharmacodynamic parameter as compared to conventional system Therefore, phyto-vesicles are called as conduit between conventional and novel drug delivery system.
Rasyid, Hermawan Nagar
Although application of biomaterials has been one of the major assets in modern medicine to improve the quality of life of patients, occurrence of a chronic osteomyelitis is still a serious health threat to the individual patient. Chronic osteomyelitis can result in morbidity affecting the viability
Noonan, P K; Gonzalez, M A; Ruggirello, D; Tomlinson, J; Babcock-Atkinson, E; Ray, M; Golub, A; Cohen, A
The purpose of this study was to measure the bioavailability of nitroglycerin from a new transdermal delivery system, Nitro-Dur II, relative to that of Nitro-Dur. Twenty-four healthy male volunteers completed a two-way crossover study. Each subject randomly received Nitro-Dur (I) and Nitro-Dur II (II) for a 24-h period. Both transdermal systems had an active surface area of 20 cm2. Blood samples were collected immediately before treatment, at 0.5, 1, 2, 3, 4, 6, 8, 12, 18, and 24 h after topical application of the units, and 30 min after the units were removed. Nitroglycerin was determined with an analytical sensitivity of 50 pg/mL using gas chromatography with electron capture detection (GC-EC). Mean steady-state concentrations of nitroglycerin were 182 and 224 pg/mL for I and II, respectively. There were no statistical differences between I and II in the pharmacokinetic parameters measured (Css, AUC, Cmax, % fluctuation). Residual nitroglycerin content was measured in each transdermal unit after application to each of the 24 volunteers. The amounts of nitroglycerin delivered by I and II were 9.78 +/- 4.11 and 10.67 +/- 4.78 mg, respectively, or approximately 10 mg in 24 h. Statistical analysis of these data using an analysis of variance indicated no significant difference between these treatments (p = 0.27). Since there were also no differences in the plasma concentrations and pharmacokinetic parameters calculated after treatment with I and II, the bioequivalence of the two delivery systems was established. PMID:3093667
Full Text Available Psoriasis is a lifelong condition which is caused by the negative signals produced by immune system, which leads to hyper proliferation and other inflammatory reactions on the skin. In this case, keratinocytes which are the outermost layer of skin possess shortened life cycle and results in the alteration of desquamation process where the cytokines will come out through lesions of affected patients and as a result, scaling marks appears on the skin. These conditions may negatively affect the patient’s quality of life and lead to psychosocial stress. Psoriasis can be categorized as mild, moderate and severe conditions. Mild psoriasis leads to the formation of rashes, and when it becomes moderate, the skin turns into scaly. In severe conditions, red patches may be present on skin surface and becomes itchy. Topical therapy continues to be one of the pillars for psoriasis management. Drug molecules with target effect on the skin tissues and other inflammations should be selected for the treatment of psoriasis. Most of the existing drugs lead to systemic intoxication and dryness when applied in higher dose. Different scientific approaches for topical delivery are being explored by researches including emollient, modified gelling system, transdermal delivery, spray, nanogels, hydrogels, micro/nano emulsion, liposomes, nano capsules etc. These topical dosage forms are evaluated for various physico chemical properties such as drug content, viscosity, pH, extrudability, spreadability, toxicity, irritancy, permeability and drug release mechanism. This review paper focus attention to the impact of these formulation approaches on various anti-psoriasis drugs for their successful treatment.
Full Text Available At present bacteria involved in biofilm associated infections display the highest rates of antibiotic resistance among pathogenic bacteria, which made that treatment options to be limited, and determined the researchers to find out alternative treatments to antibiotics. In the recent years nanomaterials gained much attention in medicine, particularly in the fight to bacteria resistant to antibiotics by acting as drug delivery devices. Magnetic iron oxide nanoparticles (MNPs have raised much interest during the recent years due to their potential applications in medicine. In the present study we synthesized MNPd functionalized with antibiotics for the study of their antimicrobial and anti-biofilm properties against Escherichia coli and Pseudomonas aeruginosa, two Gram-negative bacteria, frequently resistant to antibiotics, involved in biofilm infections in order to investigate their capacity to serve as potential drug delivery systems in the fight to these important opportunist pathogens.
Leesa Priyadarsani; Thangapalam Jawahar Abraham
Objective: To study the ecology of antibiotic resistant bacteria with emphasis on sucrose negative vibrios in water and sediments samples of traditional shrimp farming system (bhery) in West Bengal, India. Methods: The vibrios were isolated from traditional shrimp farm samples on thiosulphate citrate bthilee f rseaqltu esunccryo osfe aangtaibr ioatnidc rseuscisrotasnec nee. gative bacterial strains were used as biomarkers to assess Results: The incoming water brought presumptive vibrios ranging from 5.50×101 to 1.00×103 mL in ttoh etrhee wbhase rayb, oauntd 9t hfoelrde ainpcpreeaarseed itno vbiubirlido su. pT hvieb rleiovse lisn othf ev icburlitousr ew seyrest eombs ewrivtehd d taoy sb eo f mcuoldteurraet,e alys higher in outlet water and ranged between 4.15×102 and 4.15×103 mL. The counts of vibrios in pond sediment was found to be 1.00×102–4.90×103 g; while in inlet (2.00×102–4.20×104 g) and outlet (3.00×102–6.85×103 g) their levels were observed to be higher than the pond sediment. Thirteen wdiefrfeer seennt sVitiibvrei oto s cphelcoireasm wpehreen iecnocl,o fuonlltoewreedd ibny tcriapdriotifloonxaalc sinh rainmdp g cautilftluorxea csiyns (t9e8m.2 4a%n)d, gaelnl tvaimbircioins (t9w5o.6 1a%n)t iabniodt ioctsh,e rw aans tinboitoitcicesd. aTmheo nmgu ltiple antibiotic resistance (MAR), i.e., resistance to at least sucrose negative non-vibrios. 43.85% of the sucrose negative vibrios and 41.86% of the was used in the bhery, the preAvalll evnicberi oosf harveyi strains exhibited MAR. Although no antibiotic vibrios is a cause of concern. MAR in 44% of the sucrose negative vibrios and non- The MAR index was higher in inlet water and sediment samples. The MofA iRn loebt ssearmvepdle sin, tbhiuosm caornkfeirrm sitnragi nths eo ffa pcot nthda wt iantecor manindg sweadtiemr ewnat s( 4t0h%e) mwaajso rc osmoupracrea obfl ea ntoti bthiootsiec resistant bacteria. Conclusions: It seems that the shrimp culture in bhery does not favour the proliferation and spread
Full Text Available A prospective quasi-experimental study was undertaken in 218 patients with suspicion of nosocomial infection hospitalized in a polyvalent ICU where a new electronic device (GERB has been designed for antibiotic prescriptions. Two GERB-based applications were developed to provide local resistance maps (LRMs and preliminary microbiological reports with therapeutic recommendation (PMRTRs. Both applications used the data in the Laboratory Information System of the Microbiology Department to report on the optimal empiric therapeutic option, based on the most likely susceptibility profile of the microorganisms potentially responsible for infection in patients and taking into account the local epidemiology of the hospital department/unit. LRMs were used for antibiotic prescription in 20.2% of the patients and PMRTRs in 78.2%, and active antibiotics against the finally identified bacteria were prescribed in 80.0% of the former group and 82.4% of the latter. When neither LMRs nor PMRTRs were considered for empiric treatment prescription, only around 40% of the antibiotics prescribed were active. Hence, the percentage appropriateness of the empiric antibiotic treatments was significantly higher when LRM or PMRTR guidelines were followed rather than other criteria. LRMs and PMRTRs applications are dynamic, highly accessible, and readily interpreted instruments that contribute to the appropriateness of empiric antibiotic treatments.
Full Text Available Adeno-associated virus (AAV-mediated gene delivery has emerged as an effective and safe tool for both preclinical and clinical studies of neurological disorders. The recent discovery that several serotypes are able to cross the blood-brain-barrier when administered systemically has been a real breakthrough in the field of neurodegenerative diseases. Widespread transgene expression after systemic injection could spark interest as a therapeutic approach. Such strategy will avoid invasive brain surgery and allow non-focal gene therapy promising for CNS diseases affecting large portion of the brain. Here, we will review the recent results achieved through different systemic routes of injection generated in the last decade using systemic AAV-mediated delivery and propose a brief assessment of their values. In particular, we emphasize how the methods used for virus engineering could improve brain transduction after peripheral delivery.
Uday Prakash; Lalit Singh; Vijay Sharma
Floating drug delivery system is the form of gastro-retentive drug delivery system. That controls kinetic release rate of drug to a specific site for its pharmacological action. These are achieved by use of various polymeric substances including natural polymer such as xanthan gum. This delivery system prolongs the retention time of the drug in the stomach as compared to conventional dosage form. The present article highlights the use of xanthan gum for the formulation of the gastro-retentive...
WANG Youxiang; SHEN Jiacong
Gene delivery systems are one of key issues that limit the development of gene therapy. The novel non-viral gene delivery systems fabricated via supramolecular assembly have begun to show increasing promising and applications in gene therapy due to its suitable nanometric size, controllable structure and excellent biocompatibility. In this review, the fundamental and recent progress of non-viral gene supramolecular assembly is reviewed. Artificial viruses--the future direction of non-viral gene delivery systems are also described.
Full Text Available Wonkyung Cho,1,2 Min-Soo Kim,3 Jeong-Soo Kim,2 Junsung Park,1,2 Hee Jun Park,1,2 Kwang-Ho Cha,1,2 Jeong-Sook Park,2 Sung-Joo Hwang1,4 1Yonsei Institute of Pharmaceutical Sciences, Yonsei University, Incheon, Republic of Korea; 2College of Pharmacy, Chungnam National University, Daejeon, Republic of Korea; 3Department of Pharmaceutical Engineering, Inje University, Gimhae, Republic of Korea; 4College of Pharmacy, Yonsei University, Incheon, Republic of Korea Background: The aim of this study was to develop an optimized solid self-microemulsifying drug delivery system (SMEDDS formulation for sirolimus to enhance its solubility, stability, and bioavailability. Methods: Excipients used for enhancing the solubility and stability of sirolimus were screened. A phase-separation test, visual observation for emulsifying efficiency, and droplet size analysis were performed. Ternary phase diagrams were constructed to optimize the liquid SMEDDS formulation. The selected liquid SMEDDS formulations were prepared into solid form. The dissolution profiles and pharmacokinetic profiles in rats were analyzed. Results: In the results of the oil and cosolvent screening studies, Capryol™ Propylene glycol monocaprylate (PGMC and glycofurol exhibited the highest solubility of all oils and cosolvents, respectively. In the surfactant screening test, D-α-tocopheryl polyethylene glycol 1000 succinate (vitamin E TPGS was determined to be the most effective stabilizer of sirolimus in pH 1.2 simulated gastric fluids. The optimal formulation determined by the construction of ternary phase diagrams was the T32 (Capryol™ PGMC:glycofurol:vitamin E TPGS = 30:30:40 weight ratio formulation with a mean droplet size of 108.2 ± 11.4 nm. The solid SMEDDS formulations were prepared with Sucroester 15 and mannitol. The droplet size of the reconstituted solid SMEDDS showed no significant difference compared with the liquid SMEDDS. In the dissolution study, the release amounts of
Peggs, Stephen G.; Brennan, J. Michael; Tuozzolo, Joseph E.; Zaltsman, Alexander
A medical synchrotron which cycles rapidly in order to accelerate particles for delivery in a beam therapy system. The synchrotron generally includes a radiofrequency (RF) cavity for accelerating the particles as a beam and a plurality of combined function magnets arranged in a ring. Each of the combined function magnets performs two functions. The first function of the combined function magnet is to bend the particle beam along an orbital path around the ring. The second function of the combined function magnet is to focus or defocus the particle beam as it travels around the path. The radiofrequency (RF) cavity is a ferrite loaded cavity adapted for high speed frequency swings for rapid cycling acceleration of the particles.
and how to fully integrate safety in each part of the process. The result is a concept and guideline including control forms for how to integrate safety design in the Building Delivery System plus what to do and when. The concept has been tested in an educational context. The practical value...... of the concept depends, nevertheless, on how you manage and organise the detailed design process. In the end, prioritization, motivation and leadership are of vital importance to the construction process and to how good the safety at the site will be for the craftsmen. The developed concept has to be seen......In construction, it is important to view safety and health as an integrated part of the way that “designers” are working. The designers cowers architects, constructors, engineers and others who carry out their consulting services in the design phase of a construction project. The philosophy...
Kenawy, E.; Abdel-Hay, F. I.; El-Newehy, M. H.; Wnek, G. E.
The use of electrospun fibers as drug carriers could be promising in the future for biomedical applications, especially postoperative local chemotherapy. In this research, electrospun fibers were developed as a new system for the delivery of ketoprofen as non-steroidal anti-inflammatory drug (NSAID). The fibers were made either from polycaprolactone (PCL) as a biodegradable polymer or polyurethane (PU) as a non-biodegradable polymer, or from the blends of the two. The release of the ketoprofen was followed by UV—VIS spectroscopy in phosphate buffer of pH 7.4 at 37°C and 20°C. The results showed that the release rates from the polycaprolactone, polyurethane and their blend were similar. However, the blend of the polycaprolactone with polyurethane improved its visual mechanical properties. Release profiles from the electrospun mats were compared to cast films of the various formulations.
Obaru, K; Mitsuya, H
A number of candidate drugs for therapy of HIV-1 infection which show significant activity against the virus in vitro were reported; however, many of them have been dropped from drug development due to (i) insufficient intracellular activation in certain human target cells (particularly in case of nucleoside reverse transcriptase inhibitors), (ii) poor pharmacokinetic profiles, or (iii) intolerable in vitro and/or in vivo toxicities. To circumvent some of these problems, certain drug delivery systems have been applied and several candidate drugs including two novel nucleoside reverse transcriptase inhibitors, abacavir and adefovir, have acquired favorable properties in the clinical setting. This paper reviews several avenues for developing prodrugs of anti-HIV-1 agents to overcome their inherent limitations. PMID:9549371
Steven, Christopher R.; Busby, Grahame A.; Mather, Craig;
Silica nanoparticles have been shown to have great potential as drug delivery systems (DDS), however, their fabrication often involves harsh chemicals and energy intensive laborious methods. This work details the employment of a bioinspired "green" method for the controlled synthesis of silica, use...... of the products to entrap and release drug molecules and their cytotoxicity in order to develop novel DDS. Bioinspired silica synthesis occurs at pH 7, room temperature and in less than 5 minutes, resulting in a rapid, cheaper and greener route. Drugs were loaded into silica during the silica formation, thus...... allowing a one step and one pot method for simultaneous silica synthesis and drug loading. We established that the drug release profile can be modulated by synthetic parameters, which can allow design of tailored DDS. A systematic investigation using a two level factorial design was adopted in order...
Martín, Roberto; Alvaro, Mercedes; Herance, José Raúl; García, Hermenegildo
When raw diamond nanoparticles (Dnp, 7 nm average particle size) obtained from detonation are submitted to harsh Fenton-treatment, the resulting material becomes free of amorphous soot matter and the process maintains the crystallinity, reduces the particle size (4 nm average particle size), increases the surface OH population, and increases water solubility. All these changes are beneficial for subsequent Dnp covalent functionalization and for the ability of Dnp to cross cell membranes. Fenton-treated Dnps have been functionalized with thionine and the resulting sample has been observed in HeLa cell nuclei. A triethylammonium-functionalized Dnp pairs electrostatically with a plasmid having the green fluorescent protein gene and acts as gene delivery system permitting the plasmid to cross HeLa cell membrane, something that does not occur for the plasmid alone without assistance of polycationic Dnp. PMID:20047335
Tumor targetability and stimuli responsivity of drug delivery systems (DDS) are key factors in cancer therapy. Implementation of multifunctional DDS can afford targetability and responsivity at the same time. Herein, cholesterol molecules (Ch) were coupled to hyaluronic acid (HA) backbones to afford amphiphilic conjugates that can self-assemble into stable micelles. Doxorubicin (DOX), an anticancer drug, and superparamagnetic iron oxide (SPIO) nanoparticles (NPs), magnetic resonance imaging (MRI) contrast agents, were encapsulated by Ch-HA micelles and were selectively released in the presence of hyaluronidase (Hyals) enzyme. Cytotoxicity and cell uptake studies were done using three cancer cell lines (HeLa, HepG2 and MCF7) and one normal cell line (WI38). Higher Ch-HA micelles uptake was seen in cancer cells versus normal cells. Consequently, DOX release was elevated in cancer cells causing higher cytotoxicity and enhanced cell death. © 2012 The Royal Society of Chemistry.
Oluyomi S.Adeyemi; Faoziyat A.Sulaiman
Diminazene aceturate is a trypanocide with unwanted toxicity and limited efficacy.It was reasoned that conjugating diminazene aceturate to functionalized nanoparticle would lower untoward toxicity while improving selectivity and therapeutic efficacy.Silver and gold nanoparticles were evaluated for their capacities to serve as carriers for diminazene aceturate.The silver and gold nanoparticles were synthesized,functionalized and coupled to diminazene aceturate following established protocols.The nanoparticle conjugates were characterized.The free diminazene aceturate and drug conjugated nanoparticles were subsequently evaluated for cytotoxicity in vitro.The characterizations by transmission electron microscopy or UV/Vis spectroscopy revealed that conjugation of diminazene aceturate to silver or gold nanoparticles was successful.Evaluation for cytotoxic actions in vitro demonstrated no significance difference between free diminazene aceturate and the conjugates.Our data suggest that surface modified metal nanoparticles could be optimized for drug delivery systems.
Choi, M J; Maibach, H I
Skin acts a major target as well as a principle barrier for topical/transdermal drug delivery. Despite the many advantages of this system, the major obstacle is the low diffusion rate of drugs across the stratum corneum. Several methods have been assessed to increase the permeation rate of drugs temporarily. One simple and convenient approach is application of drugs in formulation with elastic vesicles or skin enhancers. Elastic vesicles are classified with phospholipid (Transfersomes((R)) and ethosomes) and detergent-based types. Elastic vesicles were more efficient at delivering a low and high molecular weight drug to the skin in terms of quantity and depth. Their effectiveness strongly depends on their physicochemical properties: composition, duration and application volume, and entrapment efficiency and application methods. This review focuses on the effect of elastic liposomes for enhancing the drug penetration and defines the action mechanism of penetration into deeper skin. PMID:18492190
Marquardt, J.; Keller, J.; Mills, G.; Schmidt, J.
Starting on the Gemini program in the 1960s, Beech Aircraft (now Ball Aerospace) has been designing and manufacturing dewars for a variety of cryogens including liquid hydrogen and oxygen. These dewars flew on the Apollo, Skylab and Space Shuttle spacecraft providing fuel cell reactants resulting in over 150 manned spaceflights. Since Space Shuttle, Ball has also built the liquid hydrogen fuel tanks for the Boeing Phantom Eye unmanned aerial vehicle. Returning back to its fuel cell days, Ball has designed, built and tested a volume-constrained liquid hydrogen and oxygen tank system for reactant delivery to fuel cells on unmanned undersea vehicles (UUVs). Herein past history of Ball technology is described. Testing has been completed on the UUV specific design, which will be described.
A thermo-responsive chitosan hydrogel system (TRCHS) was prepared by chitosan ( CS ) andβ- glycerophosphate ( β- GP ) to deliver Adriamycin (ADM) locally for curing osteosarcoma . Release property was investigated by release experiments in vitro and results show that it can be applied to local drug release because it is able to release drug at high concentration for 17 days. The treatment effect was studied by injecting intratumorally to osteosarcoma tumors ( CRL- 1427) implanted subcutaneously on Specific Pathogen-free (SPF) mice. The statistical analytical results show that TRCHS delivering ADM is more efficacious than saline intratumoral injection,which loads the same quantity of ADM , but is less poisonous. Based on the analysis above, this novel biodegradable polymer implant is an effective and safe vehicle for sustained local delivery of ADM, and is supposed to be applied in neoadjuvant chemotherapy for osteosarcoma.
We perform engineering cost analyses of systems capable of delivering 1–5 million metric tonnes (Mt) of albedo modification material to altitudes of 18–30 km. The goal is to compare a range of delivery systems evaluated on a consistent cost basis. Cost estimates are developed with statistical cost estimating relationships based on historical costs of aerospace development programs and operations concepts using labor rates appropriate to the operations. We evaluate existing aircraft cost of acquisition and operations, perform in-depth new aircraft and airship design studies and cost analyses, and survey rockets, guns, and suspended gas and slurry pipes, comparing their costs to those of aircraft and airships. Annual costs for delivery systems based on new aircraft designs are estimated to be $1–3B to deliver 1 Mt to 20–30 km or $2–8B to deliver 5 Mt to the same altitude range. Costs for hybrid airships may be competitive, but their large surface area complicates operations in high altitude wind shear, and development costs are more uncertain than those for airplanes. Pipes suspended by floating platforms provide low recurring costs to pump a liquid or gas to altitudes as high as ∼ 20 km, but the research, development, testing and evaluation costs of these systems are high and carry a large uncertainty; the pipe system’s high operating pressures and tensile strength requirements bring the feasibility of this system into question. The costs for rockets and guns are significantly higher than those for other systems. We conclude that (a) the basic technological capability to deliver material to the stratosphere at million tonne per year rates exists today, (b) based on prior literature, a few million tonnes per year would be sufficient to alter radiative forcing by an amount roughly equivalent to the growth of anticipated greenhouse gas forcing over the next half century, and that (c) several different methods could possibly deliver this quantity for less
Hvam, Lars; Mortensen, Niels Henrik; Thuesen, Christian;
This article describes the concepts system products and system deliveries based on the use of product modularization and product configuration. The concepts are outlined and discussed based on examples from both the construction industry and related industry. The description focuses partly...
Full Text Available Problem statement: Traditional scheduling models which only address the sequence of jobs to be processed at the production stage under some criteria are no longer suitable and should be extended to cope with the distribution stage after production. In a rapidly changing environment, competition among enterprises has a tendency to turn towards competing between supply chain systems instead of competing between individual companies. Emphasizing on the coordination and the integration among various members of a supply chain has become one of the vital strategies for the modern manufacturers to gain competitive advantages. Approach: This research focuses mainly on a class of two-stage scheduling problem, in which jobs need to be delivered to customers by vehicles after the completion of their respective production. It is assumed that the transportation time of a vehicle is constant and jobs to be delivered occupy different physical spaces. Results: The result of this research is to show the scheduling problem with the objective of minimizing total completion time is intractable and to develop a heuristic by incorporating properties inherited in an the optimal schedule. In addition, we take a Decision Support System (DSS view to construct a Scheduling Support System (SSS for solving the scheduling problem with delivery coordination. Conclusion/Recommendations: The scheduling support system with an additional problem management subsystem can provide more useful information for users when the management makes a strategic decision than traditional scheduling methods can. It can give firms a competitive advantage on the global competitive market.
Several angiographic techniques have been developed to image the arterial system, the commonest using iodinated contrast media. Useful as they may be, they are not without disadvantages. One other modality is angiography using CO2. Although CO2 can be used as an alternative contrast medium, delivery systems are expensive to procure. We describe an indigenous and effective delivery system developed at our institute
Hearnden, Vanessa; Sankar, Vidya; Hull, Katrusha; Juras, Danica Vidović; Greenberg, Martin; Kerr, A Ross; Lockhart, Peter B; Patton, Lauren L; Porter, Stephen; Thornhill, Martin H
The oral mucosa's accessibility, excellent blood supply, by-pass of hepatic first-pass metabolism, rapid repair and permeability profile make it an attractive site for local and systemic drug delivery. Technological advances in mucoadhesives, sustained drug release, permeability enhancers and drug delivery vectors are increasing the efficient delivery of drugs to treat oral and systemic diseases. When treating oral diseases, these advances result in enhanced therapeutic efficacy, reduced drug wastage and the prospect of using biological agents such as genes, peptides and antibodies. These technologies are also increasing the repertoire of drugs that can be delivered across the oral mucosa to treat systemic diseases. Trans-mucosal delivery is now a favoured route for non-parenteral administration of emergency drugs and agents where a rapid onset of action is required. Furthermore, advances in drug delivery technology are bringing forward the likelihood of transmucosal systemic delivery of biological agents.
Burns, III, William Wesley (Inventor); Wilson, Thomas George (Inventor)
This invention provides a method and apparatus for determining a precise switching sequence for the power switching elements of electric power delivery systems of the on-off switching type and which enables extremely fast transient response, precise regulation and highly stable operation. The control utilizes the values of the power delivery system power handling network components, a desired output characteristic, a system timing parameter, and the externally imposed operating conditions to determine where steady state operations should be in order to yield desired output characteristics for the given system specifications. The actual state of the power delivery system is continuously monitored and compared to a state-space boundary which is derived from the desired equilibrium condition, and from the information obtained from this comparison, the system is moved to the desired equilibrium condition in one cycle of switching control. Since the controller continuously monitors the power delivery system's externally imposed operating conditions, a change in the conditions is immediately sensed and a new equilibrium condition is determined and achieved, again in a single cycle of switching control.
Xu, Like; Ouyang, Weiying; Qian, Yanyun; Su, Chao; Su, Jianqiang; Chen, Hong
Antibiotic resistance genes (ARGs) are present in surface water and often cannot be completely eliminated by drinking water treatment plants (DWTPs). Improper elimination of the ARG-harboring microorganisms contaminates the water supply and would lead to animal and human disease. Therefore, it is of utmost importance to determine the most effective ways by which DWTPs can eliminate ARGs. Here, we tested water samples from two DWTPs and distribution systems and detected the presence of 285 ARGs, 8 transposases, and intI-1 by utilizing high-throughput qPCR. The prevalence of ARGs differed in the two DWTPs, one of which employed conventional water treatments while the other had advanced treatment processes. The relative abundance of ARGs increased significantly after the treatment with biological activated carbon (BAC), raising the number of detected ARGs from 76 to 150. Furthermore, the final chlorination step enhanced the relative abundance of ARGs in the finished water generated from both DWTPs. The total enrichment of ARGs varied from 6.4-to 109.2-fold in tap water compared to finished water, among which beta-lactam resistance genes displayed the highest enrichment. Six transposase genes were detected in tap water samples, with the transposase gene TnpA-04 showing the greatest enrichment (up to 124.9-fold). We observed significant positive correlations between ARGs and mobile genetic elements (MGEs) during the distribution systems, indicating that transposases and intI-1 may contribute to antibiotic resistance in drinking water. To our knowledge, this is the first study to investigate the diversity and abundance of ARGs in drinking water treatment systems utilizing high-throughput qPCR techniques in China.
Christophersen, Philip Carsten; Fano, Mathias; Saaby, Lasse;
Oral drug delivery is a preferred route because of good patient compliance. However, most peptide/ protein drugs are delivered via parenteral routes because of the absorption barriers in the gastrointestinal (GI) tract such as enzymatic degradation by proteases and low permeability acrossthe biol...
Full Text Available Neurodegenerative monogenic diseases can also affect a broad range of tissues and organs throughout the body. An effective treatment would require a systemic approach. The intravenous administration of novel therapies is ideal but is hampered by the inability of such drugs to cross the blood-brain barrier and precludes efficacy in the central nervous system. A number of these early lethal intractable diseases also present devastating irreversible pathology at birth or soon after. Therefore, any therapy would ideally be administered during the perinatal period to prevent, stop or ameliorate disease progression. The concept of perinatal gene therapy has moved a step further towards being a feasible approach to treating such disorders. This has primarily been driven by the recent discoveries that particular serotypes of adeno-associated virus (AAV gene delivery vectors have the ability to cross the blood-brain barrier following intravenous administration. Furthermore, this has been safely demonstrated in perinatal mice and non-human primates. This review focuses on the progress made in using AAV to achieve systemic transduction and what this means for developing perinatal gene therapy for early lethal neurodegenerative diseases.
Full Text Available Despite the advancements made in drug delivery systems over the years, many challenges remain in drug delivery systems for treating chronic diseases at the personalized medicine level. The current urgent need is to develop novel strategies for targeted therapy of chronic diseases. Due to their unique properties, microelectromechanical systems (MEMS technology has been recently engineered as implantable drug delivery systems for disease therapy. This review examines the challenges faced in implementing implantable MEMS drug delivery systems in vivo and the solutions available to overcome these challenges.
Kennedy, Laura Carpin
This thesis reports new gold nanoparticle-based methods to treat chemotherapy-resistant and metastatic tumors that frequently evade conventional cancer therapies. Gold nanoparticles represent an innovative generation of diagnostic and treatment agents due to the ease with which they can be tuned to scatter or absorb a chosen wavelength of light. One area of intensive investigation in recent years is gold nanoparticle photothermal therapy (PTT), in which gold nanoparticles are used to heat and destroy cancer. This work demonstrates the utility of gold nanoparticle PTT against two categories of cancer that are currently a clinical challenge: trastuzumab-resistant breast cancer and metastatic cancer. In addition, this thesis presents a new method of gold nanoparticle delivery using T cells that increases gold nanoparticle tumor accumulation efficiency, a current challenge in the field of PTT. I ablated trastuzumab-resistant breast cancer in vitro for the first time using anti-HER2 labeled silica-gold nanoshells, demonstrating the potential utility of PTT against chemotherapy-resistant cancers. I next established for the first time the use of T cells as gold nanoparticle vehicles in vivo. When incubated with gold nanoparticles in culture, T cells can internalize up to 15000 nanoparticles per cell with no detrimental effects to T cell viability or function (e.g. migration and cytokine secretion). These AuNP-T cells can be systemically administered to tumor-bearing mice and deliver gold nanoparticles four times more efficiently than by injecting free nanoparticles. In addition, the biodistribution of AuNP-T cells correlates with the normal biodistribution of T cell carrier, suggesting the gold nanoparticle biodistribution can be modulated through the choice of nanoparticle vehicle. Finally, I apply gold nanoparticle PTT as an adjuvant treatment for T cell adoptive transfer immunotherapy (Hyperthermia-Enhanced Immunotherapy or HIT) of distant tumors in a melanoma mouse
Dening, Tahnee J; Rao, Shasha; Thomas, Nicky; Prestidge, Clive A
Lipid-based drug delivery systems (LBDDS) have gained significant attention in recent times, owing to their ability to overcome the challenges limiting the oral delivery of poorly water-soluble drugs. Despite the successful commercialization of several LBDDS products over the years, a large discrepancy exists between the number of poorly water-soluble drugs displaying suboptimal in vivo performances and the application of LBDDS to mitigate their various delivery challenges. Conventional LBDDS, including lipid solutions and suspensions, emulsions, and self-emulsifying formulations, suffer from various drawbacks limiting their widespread use and commercialization. Accordingly, solid-state LBDDS, fabricated by adsorbing LBDDS onto a chemically inert solid carrier material, have attracted substantial interest as a viable means of stabilizing LBDDS whilst eliminating some of the various limitations. This review describes the impact of solid carrier choice on LBDDS performance and highlights the importance of appropriate solid carrier material selection when designing hybrid solid-state LBDDS. Specifically, emphasis is placed on discussing the ability of the specific solid carrier to modulate drug release, control lipase action and lipid digestion, and enhance biopharmaceutical performance above the original liquid-state LBDDS. To encourage the interested reader to consider their solid carrier choice on a higher level, various novel materials with the potential for future use as solid carriers for LBDDS are described. This review is highly significant in guiding future research directions in the solid-state LBDDS field and fostering the translation of these delivery systems to the pharmaceutical marketplace.
Castro, S. L.; Ott, C. M.; Douglas, G. L.
As mission distance and duration increase, the need grows for non-invasive disease prevention and immunomodulation, especially given the limited medical response capability expected for these missions and the immune dysregulation documented in crew. Additionally, changes in diet, lifestyle, antibiotic usage, and the environmental stresses during spaceflight may alter crewmembers' intestinal microbiome. The addition of probiotic bacteria to the space food system is expected to confer immunostimulatory benefits on crewmembers, with the potential to counteract the immune dysregulation that has been documented in spaceflight. Based on previous studies that demonstrated unique microbiological responses to the low shear environment of spaceflight, probiotic organisms hold the potential to induce enhanced beneficial responses through mechanisms, such as beneficial interactions with human immune cells and repression of colonization of pathogens on the mucosa. The work presented here will begin to address two research gaps related to providing probiotics in spaceflight: 1) delivery, and 2) the effect of the low shear microgravity environment on probiotic attributes. The probiotic Lactobacillus acidophilus was selected for investigation due to its wide commercial use and documented benefits that include inhibition of virulence related gene expression in pathogens and mucosal stimulation of immune cells. The delivery system for probiotics has not been determined for spaceflight, where the food system is shelf stable and the lack of refrigeration prevents the use of traditional dairy delivery methods. In order to demonstrate the potential of the space food system to deliver viable probiotic bacteria to crewmembers, the probiotic L. acidophilus was packaged in high barrier flight packaging in nonfat dry milk (NFDM) or retained in commercial capsule form. Viable cells were enumerated over 8 months of storage at 22, 4, and -80ºC. The survival of L. acidophilus rehydrated in NFDM
Song, Yunmei; Peressin, Karl; Wong, Pooi Yin; Page, Stephen W; Garg, Sanjay
The present review discusses the pharmaceutical impact of the anatomy and physiology of the canine gastrointestinal tract to provide a comprehensive guide to the theories and challenges associated with the development of oral drug delivery systems for dogs. Novel pharmaceutical technologies applied to veterinary drugs are discussed indicating the advantages and benefits for animals. There are currently immense research and development efforts being funneled into novel canine health products. Such products are being used to overcome limitations of drugs that display site-dependent absorption or possess poor biopharmaceutical properties. Techniques that are employed to increase bioavailability of the Biopharmaceutics Classification System class II drugs are discussed in this article. Furthermore, an overview of palatable oral formulations for dog care is provided as an approach to easy administration. In vitro and in vivo evaluation and correlation of oral drug formulations in dogs are also addressed. This article assesses the outlook of canine oral drug development recognizing substantial growth forecasts of the dog care market. PMID:27056627
Jain, Sunil K; Agrawal, Govind P; Jain, Narendra K
A floating granular delivery system consisting of calcium silicate (CS) as porous carrier; repaglinide (Rg), an oral hypoglycemic agent; and hydroxypropyl methylcellulose K4M (HPMC K4M), ethyl cellulose (EC) and carbopol 940 (CP940) as matrix forming polymers was prepared and evaluated for its gastro-retentive and controlled release properties. The effect of various formulation and process variables on the particle morphology, micromeritic properties, in vitro floating behavior, drug content (%) and in vitro drug release was studied. The transit of floating granules of optimized formulation in the gastrointestinal (GI) tract was monitored by gamma scintigraphy in albino rabbits. The optimized formulation was compared in vivo with lactose granules (RgSCLG) prepared from identical polymers with their optimized composition ratio. Repaglinide-loaded optimized formulation was orally administered to albino rabbits and blood samples collected were used to determine pharmacokinetic parameters of Rg from floating granular formulation. Results were compared with pharmacokinetic parameters of marketed tablet formulation of Rg. The optimized formulation (RgSCG4) demonstrated favorable in vitro floating and release characteristics. Prolonged gastric residence time (GRT) of over 6 hr was achieved in all subjects for calcium silicate based floating granules of Rg. The relative bioavailability of Rg-loaded floating granules increased 3.8-fold in comparison to that of its marketed capsule. The designed system, combining excellent buoyant ability and suitable drug release pattern, offered clear advantages in terms of increased bioavailability of repaglinide. PMID:17523003
This work describes the properties of drug delivery system (DDS) produced using micelles entrapment approach. Isoniazid, which is a water soluble drug for tuberculosis was used in the system. The effects of synthesis parameters were systematically studied such as synthesis temperature (38- 70 degree Celsius), amount of butanol co-solvent (6-18 ml), and amount of Si organic precursor (2-8 ml). From transmission electron microscope (TEM) images, the size of DDS could be tuned from 21-104 nm by changing the reaction temperature. While, the increase of butanol cosolvent enlarged the size of DDS in the range of 40-94 nm. A similar trend was observed for DDS with increasing organic Si precursor whereby the particle size could be tuned from 40-132 nm. However, at high amount of organic Si precursor of > 2 ml, a bimodal structure of DDS was observed. Stability study in biological media at 37 degree Celsius of selected samples showed that the produced DDS had acceptable degree of agglomeration (author)
Degenerative retinopathies, including age-related macular degeneration, diabetic retinopathy, and hereditary retinal disorders--major causes of world blindness--are potentially treatable by using low-molecular weight neuroprotective, antiapoptotic, or antineovascular drugs. These agents are, however, not in current systemic use owing to, among other factors, their inability to passively diffuse across the microvasculature of the retina because of the presence of the inner blood-retina barrier (iBRB). Moreover, preclinical assessment of the efficacies of new formulations in the treatment of such conditions is similarly compromised. We describe here an experimental process for RNAi-mediated, size-selective, transient, and reversible modulation of the iBRB in mice to molecules up to 800 Da by suppression of transcripts encoding claudin-5, a protein component of the tight junctions of the inner retinal vasculature. MRI produced no evidence indicative of brain or retinal edema, and the process resulted in minimal disturbance of global transcriptional patterns analyzed in neuronal tissue. We show that visual function can be improved in IMPDH1(-\\/-) mice, a model of autosomal recessive retinitis pigmentosa, and that the rate of photoreceptor cell death can be reduced in a model of light-induced retinal degeneration by systemic drug delivery after reversible barrier opening. These findings provide a platform for high-throughput drug screening in models of retinal degeneration, and they ultimately could result in the development of a novel "humanized" approach to therapy for conditions with little or no current forms of treatment.
Full Text Available Oral sustained release gastroretentive dosage forms offer many advantages for drugs having absorption from the upper gastrointestinal tract and improve the bioavailability of medications that are characterized by the narrow absorption window. A new gastroretentive sustained release delivery system using the novel effervescent system was developed with floating, swellable, and bioadhesive properties. Various release retarding polymers like psyllium husk, HPMC K15M, and a swelling agent crosspovidone in different combinations were tried and optimized to get the release profile for 12hours. The formulations were evaluated for physicochemical characteristics, in vitro drug release profile, swelling characteristics, floating capacity, and in vitro bioadhesive property. i0 n vitro drug release followed the Higuchi kinetics and the release mechanism was found to be of a non-Fickian type. The swelling properties were increased with increasing crosspovidone concentration and contributed to the drug release from the tablet matrix. In this study, an attempt has been made to explore novel effervescent agents such as citroglycine and disodium glycine carbonate for achieving the desired floating time.
M. H. Alai et al.
Full Text Available Carbon nanotubes are cylindrical carbon molecules have novel properties, making them potentially useful in many applications in nanotechnology, electronics, optics, and other fields of material science as well as potential uses in architectural fields. They have unique electronic, mechanical, optical and chemical properties that make them good candidates for a wide variety of applications, including drug transporters, new therapeutics, delivery systems and diagnostics. Their unique surface area, stiffness, strength and resilience have led to much excitement in the field of pharmacy. Nanotubes are categorized as single-walled nanotubes, multiple walled nanotubes. Various techniques have been developed to produce nanotubes in sizeable quantities, including arc discharge, laser ablation, chemical vapor deposition. They can pass through membranes, carrying therapeutic drugs, vaccines and nucleic acids deep into the cell to targets previously unreachable. Purification of the tubes can be divided into a couple of main techniques: oxidation, acid treatment, annealing, sonication, filtering and functionalization techniques. The main problem of insolubility in aqueous media has been solved by developing a synthetic protocol that allows highly water-soluble carbon NTs to be obtained. The modifications are done to improve efficiency of carbon nanotubes by formulating luminescent carbon nanotubes, ultrathin carbon nanoneedles, magnetically guided nanotubes. The application of carbon nanotube in tissue engineering, drug carrier release system, wound healing, in cancer treatment and as biosensor. Researchers have recently developed a new approach to Boron Neutron Capture Therapy in the treatment of cancer using substituted Carborane-Appended Water-Soluble single-wall carbon nanotubes.
Allard, J. Brad; Golden, Diane Cordry
Comparison of three audiology service delivery systems--(1) school-based audiology within the district, (2) non-school-based audiology in the community, and (3) school-based audiology in a remote community--found the local school-based delivery system superior on various quality indicators. (Author/DB)
... hemodialysis. 876.5600 Section 876.5600 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND....5600 Sorbent regenerated dialysate delivery system for hemodialysis. (a) Identification. A sorbent regenerated dialysate delivery system for hemodialysis is a device that is part of an artificial kidney...
Darbas, H; Boyer, G; Cavadore, D
After determining the LSI80 (light scattering index 80) concentration X and Y of two antibiotics for a given bacteria by an automated light scatter photometric method, we use the same process to test the bacteriostatic effect of all the combinations between the values 2X, X, X/2, X/4, X/8 and 2Y, Y, Y/2, Y/4, Y/8. The results read on the light scatter photometer are interpreted: --approximatealy by means of a simplified schematic diagram; --more precisely by drawing three curves: we begin with two inhibiton curves in order to determine the LSI50 concentrations (CLSI50) of each antibiotic, isolted and in the presence of defined concentrations of the complementary antibiotic; then from these CLSI50 we draw the bacteriostatic effect curve of the combination. When the LSI50 effect of the combination occurs with less than 50% of the CLSI50 of each isolated antibiotic, the combination is synergistic. It is antagonist if the bacteriostase is obtained with more than 100% of the CLSI50 of each isolated antibiotic. The intermediate percentages determine the indifferent effects. The additive effects come to an equilateral hyperbola passing through the points 50%-50%, 25%-75%. The Autobac system allows inoculum standardization, very simplified handlihg and automatic reading. It takes only 9 h to handle the complete process, including the determinations of the CLSI80 and the study of the combination. There is a high correlation between the results obtained and those given by the Patte and Chabbert "carre method".
Chinnakavanam Sundararaj, Sharath kumar
As all the physiological processes in our body are controlled by multiple biomolecules, comprehensive treatment of certain disease conditions may be more effectively achieved by administration of more than one type of drug. Thus, the primary objective of this research was to develop a multilayered, polymer-based system for sequential delivery of multiple drugs. This particular device was designed aimed at the treatment of periodontitis, a highly prevalent oral inflammatory disease that affects 90% of the world population. This condition is caused by bacterial biofilm on the teeth, resulting in a chronic inflammatory response that leads to loss of alveolar bone and, ultimately, the tooth. Current treatment methods for periodontitis address specific parts of the disease, with no individual treatment serving as a complete therapy. The polymers used for the fabrication of this multilayered device consists of cellulose acetate phthalate (CAP) complexed with Pluronic F-127 (P). After evaluating morphology of the resulting CAPP system, in vitro release of small molecule drugs and a model protein was studied from both single and multilayered devices. Drug release from single-layered CAPP films followed zero-order kinetics related to surface erosion property of the association polymer. Release studies from multilayered CAPP devices showed the possibility of achieving intermittent release of one type of drug as well as sequential release of more than one type of drug. Mathematical modeling accurately predicted the release profiles for both single layer and multilayered devices. After the initial characterization of the CAPP system, the device was specifically modified to achieve sequential release of drugs aimed at the treatment of periodontitis. The four types of drugs used were metronidazole, ketoprofen, doxycycline, and simvastatin to eliminate infection, inhibit inflammation, prevent tissue destruction, and aid bone regeneration, respectively. To obtain different erosion
Electronic mailing systems are the dominant communication systems in private and business matters. Public administrations deliver documents to citizens and businesses - subpoenas, legal verdicts, notifications, administrative penalties etc. However, official activities are more strongly linked to legal regulations than in civil law. Delivery of crucial and strictly personal documents raises the demand for qualified identification and non-repudiation services as featured by registered mail in the paper world. Legal requirements for electronic delivery carried-out by public administrations (eDelivery) cannot be fulfilled by standard certified mailing systems. Although the requirements for eDelivery systems may differ due to national legal regulations, this paper discusses common requirements and challenges on an abstract level. Moreover, we show how these requirements have been addressed by introducing the Austrian eDelivery system for eGovernment applications.
Full Text Available Lamin Saidykhan,1 Md Zuki Bin Abu Bakar,2 Yaya Rukayadi,1,3 Aminu Umar Kura,4 Saiful Yazan Latifah5 1Microbiology Unit, Laboratory of Natural Products, Institute of Bioscience, 2Laboratory of Anatomy and Histology, Department of Veterinary Preclinical Sciences, Faculty of Veterinary Medicine, 3Department of Food Science, Faculty of Food Science and Technology, 4Vaccine and Immunotherapeutics Laboratory Unit, Institute of Bioscience, 5Department of Biomedical Science, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Selangor Darul Ehsan, Malaysia Abstract: A local antibiotic delivery system (LADS with biodegradable drug vehicles is recognized as the most effective therapeutic approach for the treatment of osteomyelitis. However, the design of a biodegradable LADS with high therapeutic efficacy is too costly and demanding. In this research, a low-cost, facile method was used to design vancomycin-loaded aragonite nanoparticles (VANPs with the aim of understanding its potency in developing a nanoantibiotic bone implant for the treatment of osteomyelitis. The aragonite nanoparticles (ANPs were synthesized from cockle shells by a hydrothermal approach using a zwitterionic surfactant. VANPs were prepared using antibiotic ratios of several nanoparticles, and the formulation (1:4 with the highest drug-loading efficiency (54.05% was used for physicochemical, in vitro drug release, and biological evaluation. Physiochemical characterization of VANP was performed by using transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray powder diffraction, and Zetasizer. No significant differences were observed between VANP and ANP in terms of size and morphology as both samples were cubic shaped with sizes of approximately 35 nm. The Fourier transform infrared spectroscopy of VANP indicated a weak noncovalent interaction between ANP and vancomycin, while the zeta potential values were slightly increased from -19
Baier, Grit; Winzen, Svenja; Messerschmidt, Claudia; Frank, Daniela; Fichter, Michael; Gehring, Stephan; Mailänder, Volker; Landfester, Katharina
Herein, the synthesis and characterization of heparin-based nanocapsules (NCs) as potential drug delivery systems is described. For the synthesis of the heparin-based NCs, the versatile method of miniemulsion polymerization at the droplets interface was achieved resulting in narrowly distributed NCs with 180 nm in diameter. Scanning and transmission electron microscopy images showed clearly NC morphology. A highly negative charge density for the heparin-based NCs was determined by measuring the electro-kinetic potential. Measuring the activated clotting time demonstrated the biological intactness of the polymeric shell. The ability of heparin-based NCs to bind to antithrombin (AT III) was investigated using isothermal titration calorimetry and dynamic light scattering experiments. The chemical stability of the NCs was studied in physiological protein-containing solutions and also in medically interesting fluids such as sodium chloride 0.9%, Ringer's solution, and phosphate buffer saline using dynamic light scattering and measuring the fluorescence intensity. The impressive uptake of NCs in different cells was confirmed by fluorescence-activated cell sorting, confocal laser scanning microscopy, and transmission electron microscopy. The low toxicity of all types of NCs was demonstrated.
Full Text Available The present endeavor was directed towards fabrication of the novel colonic drug delivery system of ibuprofen. To begin with, the hydroxypropyl methylcellulose capsules containing adsorbate of eutectic mixture of ibuprofen and menthol and pregelatinized starch were coated with ethyl cellulose. These ethyl cellulose coated capsules were filled in another capsule and the capsules were coated with a Eudragit; S100. The in vitro drug release study was conducted using sequential dissolution technique at pH 1.2 (two hour, 6.0 (1hr, 7.2 (two hour and 6.4 (three hour mimicking different regions of gastrointestinal tract. The optimized batch with two per cent and 6.5% weight gain of ethyl cellulose and Eudragit; S100 showed less than eight per cent drug release in stomach and intestinal pH. The remaining 92% drug release was obtained thereafter from the optimized batch within two hours in colonic pH. Scanning electron microscopy study of the optimized batch confirmed presence of ibuprofen crystals (rod shape in the formulation. The infrared spectroscopy study of the optimized batch indicated stability of ibuprofen during processing of the formulation.
Full Text Available The purpose of the present work was to design and optimize floating drug delivery systems of acyclovir using psyllium husk and hydroxypropylmethylcellulose K4M as the polymers and sodium bicarbonate as a gas generating agent. The tablets were prepared by wet granulation method. A 32 full factorial design was used for optimization of drug release profile. The amount of psyllium husk (X1 and hydroxypropylmethylcellulose K4M (X2 were selected as independent variables. The times required for 50% (t 50% and 70% (t 70% drug dissolution were selected as dependent variables. All the designed nine batches of formulations were evaluated for hardness, friability, weight variation, drug content uniformity, swelling index, in vitro buoyancy, and in vitro drug release profile. All formulations had floating lag time below 3 min and constantly floated on dissolution medium for more than 24 h. Validity of the developed polynomial equation was verified by designing two check point formulations (C1 and C2. The closeness of predicted and observed values for t 50% and t 70% indicates validity of derived equations for the dependent variables. These studies indicated that the proper balance between psyllium husk and hydroxypropylmethylcellulose K4M can produce a drug dissolution profile similar to the predicted dissolution profile. The optimized formulations followed Higuchi′s kinetics while the drug release mechanism was found to be anomalous type, controlled by diffusion through the swollen matrix.
Full Text Available Plant polysaccharides consist of many monosaccharide by α- or β-glycosidic bond which can be extracted by the water, alcohol, lipophile liquid from a variety of plants including Cordyceps sinensis, astragalus, and mushrooms. Recently, many evidences illustrate that natural plant polysaccharides possess various biological activities including strengthening immunity, lowering blood sugar, regulating lipid metabolism, antioxidation, antiaging, and antitumour. Plant polysaccharides have been widely used in the medical field due to their special features and low toxicity. As an important drug delivery system, liposomes can not only encapsulate small-molecule compound but also big-molecule drug; therefore, they present great promise for the application of plant polysaccharides with unique physical and chemical properties and make remarkable successes. This paper summarized the current progress in plant polysaccharides liposomes, gave an overview on their experiment design method, preparation, and formulation, characterization and quality control, as well as in vivo and in vitro studies. Moreover, the potential application of plant polysaccharides liposomes was prospected as well.
Tuncay, Sakine; Özer, Özgen
Nicotinamide (NA) has been shown to have beneficial effects on several skin diseases such as tumor, acne vulgaris, photodamage, cellulite and atopic dermatitis. The purpose of this study was to develop a multiple emulsion and a microemulsion formulation as delivery systems for NA. A two-step process was used to prepare the W/O/W multiple emulsion. Optimum microemulsion formulation was selected by using construction of pseudo-ternary phase diagram. The physicochemical properties such as droplet size and viscosity measurements, stability studies were also evaluated. Ex-vivo permeation studies were performed with Franz-type diffusion cells and the samples were analysed by high performance liquid chromatography (HPLC). The permeation data showed that there was no significant difference between multiple emulsion and microemulsion (p > 0.05). Transepidermal water loss (TEWL) was also measured. As a result of TEWL studies, a slight increase of TEWL values was observed for microemulsion formulation on rat skin when compared with multiple emulsion and commercial formulation. The results suggested that microemulsion and multiple emulsion formulations could be new and alternative dosage forms for topical application of NA.
Full Text Available Buccoadhesive buccal delivery systems for isosorbide dinitrate in the form of unidirectional buccal films were developed and characterized for improving bioavailability. The films were formulated by solvent casting method using different bioadhesive polymers like Carbopol 934P and polyvinyl pyrrolidone by using two different plasticizers propylene glycol and diethyl phthalate. Unidirectional release was achieved by preparing composite films with backing membrane. The films were characterized on the basis of their physical characteristics, bioadhesive performance, and other parameters. In vitro studies revealed that release rate of isosorbide dinitrate was higher from carbopol films containing ratio of Eudragit RL100 and polyvinyl pyrrolidine in proportion of 1:2 and 2:1, respectively by using both plasticizers. Drug diffusion from buccal films showed apparently zero order kinetics and release mechanism was diffusion controlled after considerable swelling. All the films exhibited sufficient in vitro bioadhesion strength. Promising formulations were further studied for temperature dependent stability studies. Results of our preliminary experiments indicate that, therapeutic level of isosorbide dinitrate can be achieved using this buccaladhesive formulation.
Kharia, A A; Hiremath, S N; Singhai, A K; Omray, L K; Jain, S K
The purpose of the present work was to design and optimize floating drug delivery systems of acyclovir using psyllium husk and hydroxypropylmethylcellulose K4M as the polymers and sodium bicarbonate as a gas generating agent. The tablets were prepared by wet granulation method. A 3(2) full factorial design was used for optimization of drug release profile. The amount of psyllium husk (X1) and hydroxypropylmethylcellulose K4M (X2) were selected as independent variables. The times required for 50% (t(50%)) and 70% (t(70%)) drug dissolution were selected as dependent variables. All the designed nine batches of formulations were evaluated for hardness, friability, weight variation, drug content uniformity, swelling index, in vitro buoyancy, and in vitro drug release profile. All formulations had floating lag time below 3 min and constantly floated on dissolution medium for more than 24 h. Validity of the developed polynomial equation was verified by designing two check point formulations (C1 and C2). The closeness of predicted and observed values for t(50%) and t(70%) indicates validity of derived equations for the dependent variables. These studies indicated that the proper balance between psyllium husk and hydroxypropylmethylcellulose K4M can produce a drug dissolution profile similar to the predicted dissolution profile. The optimized formulations followed Higuchi's kinetics while the drug release mechanism was found to be anomalous type, controlled by diffusion through the swollen matrix. PMID:21694992
Psek, Wayne; Davis, F. Daniel; Gerrity, Gloria; Stametz, Rebecca; Bailey-Davis, Lisa; Henninger, Debra; Sellers, Dorothy; Darer, Jonathan
Introduction: Healthcare leaders need operational strategies that support organizational learning for continued improvement and value generation. The learning health system (LHS) model may provide leaders with such strategies; however, little is known about leaders’ perspectives on the value and application of system-wide operationalization of the LHS model. The objective of this project was to solicit and analyze senior health system leaders’ perspectives on the LHS and learning activities in an integrated delivery system. Methods: A series of interviews were conducted with 41 system leaders from a broad range of clinical and administrative areas across an integrated delivery system. Leaders’ responses were categorized into themes. Findings: Ten major themes emerged from our conversations with leaders. While leaders generally expressed support for the concept of the LHS and enhanced system-wide learning, their concerns and suggestions for operationalization where strongly aligned with their functional area and strategic goals. Discussion: Our findings suggests that leaders tend to adopt a very pragmatic approach to learning. Leaders expressed a dichotomy between the operational imperative to execute operational objectives efficiently and the need for rigorous evaluation. Alignment of learning activities with system-wide strategic and operational priorities is important to gain leadership support and resources. Practical approaches to addressing opportunities and challenges identified in the themes are discussed. Conclusion: Continuous learning is an ongoing, multi-disciplinary function of a health care delivery system. Findings from this and other research may be used to inform and prioritize system-wide learning objectives and strategies which support reliable, high value care delivery. PMID:27683668
Jethara, Sahilhusen I; Patel, Alpesh D; Patel, Mukesh R
Self-Emulsifying Drug Delivery System is a unique feasible approach to overcome low oral bioavailability problem which is associated with the hydrophobic drugs due to their unparalleled potential as a drug delivery with the broad range of application. The estimated 40% of active pharmaceuticals are poorly water soluble. Now recently, formulation containing oral SEDDS has received much interest as it solve problems related to oral bioavailability, intra and inter-subject variability and lack of dose proportionality of hydrophobic drugs. Now a days, it is the first way to investigate the development of any kind of innovative dosage forms. Many important in-vitro characteristics such as surfactant concentration, oil/surfactant ratio, emulsion polarity, droplet size and zeta potential play an important role in oral absorption of drug from SEEDS. It can be orally administered in the form of SGC or HGC and also enhances bioavailability of drugs to increase solubility and minimizes the gastric irritation. After administration the drug remains entrapped in the oily droplets (inside the droplet or in the surfactant`s film at the interface) of the emulsion that are formed in the GIT upon self-emulsification process. It is also a bit problematic to say that the drug is being released from SMEDDS, it would be more precise to say that it diffuses out of oily droplets into the GIT media resulting in the formation of an equilibrium between the drug dissolved in oily droplets and the outer dispersed media (e.g. GIT fluids). Many of the application and preparation methods of SEDDS are reported by research articles and patents in different countries. We present an exhaustive and updated account of numerous literature reports and more than 150 patents published on SEDDS in the recent period. This current patent review is useful in knowledge of SEDDS for its preparations and patents in different countries with emphasis on their formulation, characterization and systematic optimization
Adhesives are a critical component in transdermal drug delivery (TDD) devices. In addition to the usual requirements of functional adhesive properties, adhesives for TDD applications must have good biocompatibility with the skin, chemical compatibility with the drug, various components of the formulation, and provide consistent, effective delivery of the drug. This review discusses the three most commonly used adhesives (polyisobutylenes, polyacrylates and silicones) in TDD devices, and provides an update on recently introduced TDD products and recent developments of new adhesives. PMID:10234208
D'Addio, Suzanne M.
In this thesis, a multifunctional nanocarrier drug delivery system was investigated and optimized to improve tuberculosis therapy by promoting the intracellular delivery of high payloads of antibiotics. To meet the needs of a patient population which continues to grow by close to 10 million people a year, innovative therapeutics must be formulated by robust and scalable processes. We use Flash NanoPrecipitation for the continuous precipitation of nanocarriers by block copolymer directed assembly, which enables the development of nanocarriers with tunable properties. Stable nanocarriers of Rifampicin and a hydrophobic Rifampicin prodrug have efficacy against tuberculosis in vitro that is equivalent to the soluble Rifampicin. To overcome poor in vivo efficacy of the recently discovered antitubercular drug SQ641, we co-encapsulate SQ641 and Cyclosporine A in a stable aqueous nanocarrier suspension, which enables drug administration and also enhances intracellular accumulation and antitubercular efficacy relative to SQ641 in solution. Since the mannose receptor is involved in the phagocytosis of tuberculosis bacilli, we modify the surface of nanocarriers with mannoside residues to target specific intracellular accumulation in macrophages. The surface density of mannoside terminated polyethylene glycol chains was controlled between 0 and 75% and in vitro cellular association reveals a 9% surface density is optimal for internalization mediated by the mannose receptor. We explore the preparation of large, porous aerosol carrier particles of with tunable deposition characteristics by spray freeze drying with ultrasonic atomization for direct dosing to the lungs. Nanocarriers are loaded at 3 - 50 wt% in mannitol particles with constant size, limited nanocarrier aggregation, and 63% dose delivered to the lungs, as determined by in vitro cascade impaction. There has been a lag in the development of new technologies to facilitate development and commercialization of
目的 了解阴道分娩产妇对会阴切口预防性应用抗菌药物的依从性,以期促进抗菌药物的合理使用.方法 选择医院正常阴道分娩有会阴切口的产妇共2000例为研究对象,以问卷形式调查其在产后对应用抗菌药物的依从性,包括是否接受使用抗菌药物、选择药物的种类、用药途径、用药时间及用药费用等.结果 产妇接受抗菌药物者1686例占84.3％,其中1258例占62.9％接受口服头孢类药物,404例占20.2％要求静脉用药,用药时间2～3 d,80.0％不计较用药费用;15.7％的产妇不接受抗菌药物,其中112例,占5.6％认为药物对哺乳有不良影响.结论 产妇对会阴切口预防性应用抗菌药物的依从性方面存在误区,需要开展有效的合理用药宣传教育,合理使用抗菌药物,避免不必要的医疗开支.%OBJECTIVE To improve the compliance of preventive application of antibiotics for perineum of vaginal delivery with perineum incision so that it can promote the rational use of antibiotics. METHODS The puerpera with normal perineum incision 2000 cases were researched and their compliance of application antibiotics to prevent infections was investigated by using questionnaire. The questions included the following aspects: whether or.not to accept the application of antibiotics, select the type of medicine, route, time and costs of administrating medicine, and so on. RESULTS There were 1686 puerpera accepting antibiotics (accounting for 84. 3%). There were 1258 cases accepting antibiotics (62. 9%) by oral and 404 cases by intravenous among these puerpera. The duration of using antibiotics was 2 to 3 days and they (80%) did not worry the costs. There were 404 puerpera without accepting antibiotics (20. 2%). They( 112 cases) were afraid that medicine had an adverse effect on lactation among 404 puerpera. CONCLUSION There exists the error on the aspect of compliance of prophylactic use of antibiotics for perineum incision, it
Patel, Jaydeep; Kevin, Garala; Patel, Anjali; Raval, Mihir; Sheth, Navin
Background and Aim: Telmisartan (TEL) is an angiotensin II receptor blocker (ARB) antihypertensive agent. The aim of the present investigation was to develop a self-nanoemulsifying drug delivery system (SNEDDS) to enhance the oral bioavailability of poorly water soluble TEL. Materials and Methods: The solubility of TEL in various oils was determined to identify the oil phase of a SNEDDS. Various surfactants and co-surfactants were screened for their ability to emulsify the selected oil. Pseud...
Coutts, Janelle L.; Hummerick, Mary E.; Lunn, Griffin M.; Larson, Brian D.; Spencer, LaShelle E.; Kosiba, Michael L.; Khodadad, Christina L.; Catechis, John A.; Birmele, Michele N.; Wheeler, Raymond M.
Membrane-aerated biofilm reactors (MABRs) have been studied for a number of years as an alternate approach for treating wastewater streams during space exploration. While the technology provides a promising pre-treatment for lowering organic carbon and nitrogen content without the need for harsh stabilization chemicals, several challenges must be addressed before adoption of the technology in future missions. One challenge is the transportation of bioreactors containing intact, active biofilms as a means for rapid start-up on the International Space Station or beyond. Similarly, there could be a need for placing these biological systems into a dormant state for extended periods when the system is not in use, along with the ability for rapid restart. Previous studies indicated that there was little influence of storage condition (4 or 25 C, with or without bulk fluid) on recovery of bioreactors with immature biofilms (48 days old), but that an extensive recovery time was required (20+ days). Bioreactors with fully established biofilms (13 months) were able to recover from a 7-month dormancy within 4 days (approximately 1 residence). Further dormancy and recovery testing is presented here that examines the role of biofilm age on recovery requirements, repeated dormancy cycle capabilities, and effects of long-duration dormancy cycles (8-9 months) on HFMB systems. Another challenge that must be addressed is the possibility of antibiotics entering the wastewater stream. Currently, for most laboratory tests of biological water processors, donors providing urine may not contribute to the study when taking antibiotics because the effects on the system are yet uncharacterized. A simulated urinary tract infection event, where an opportunistic, pathogenic organism, E. coli, was introduced to the HFMBs followed by dosing with an antibiotic, ciprofloxacin, was completed to study the effect of the antibiotic on reactor performance and to also examine the development of
Full Text Available Introduction : Staphylococcus aureus is considered as one of pathogenic agents in humans, that engages different body parts including respiratory system and causes to spend lots of costs and extending patient’s treatment period. This study which is performed to separate and investigate the pattern of antibiotic resistance in Staphylococcus aureus isolates from upper respiratory system infections in Shahrekord. Materials and methods: This study was done by sectional-descriptive method On 200 suspicious persons to the upper respiratory system infections who were referred to the Imam Ali clinic in Shahrekord in 2012. After isolation of Staphylococcus aureus from cultured nose discharges, antibiotic resistance genes were identified by polymerase chain reaction (PCR by using defined primer pairs . Results : Among 200 investigated samples in 60 cases (30% Staphylococcus aureus infection (by culturing and PCR method was determined. Isolates showed the lowest amount of antibiotic resistance to vancomycin (0.5% and the highest amount of resistance to the penicillin G and cefotaxime (100%. mecA gene (encoding methicillin resistance with frequency of 85.18% and aacA-D gene (encoding resistance to aminoglycosides with frequency of 28.33% showed the highest and lowest frequency of antibiotic resistance genes coding in Staphylococcus aureus isolates respectively . Discussion and conclusion : Notable prevalence of resistant Staphylococcus aureus isolates in community acquired respiratory infections, recommend continuous control necessity to impede the spreading of these bacteria and their infections.
National Aeronautics and Space Administration — We propose to develop a miniature system for acquisition and delivery of solid samples to landed planetary instruments. This system would entrain powder produced by...
Full Text Available Floating drug delivery system is the form of gastro-retentive drug delivery system. That controls kinetic release rate of drug to a specific site for its pharmacological action. These are achieved by use of various polymeric substances including natural polymer such as xanthan gum. This delivery system prolongs the retention time of the drug in the stomach as compared to conventional dosage form. The present article highlights the use of xanthan gum for the formulation of the gastro-retentive drug delivery system especially with natural polymer (xanthan gum. The main goal of any drug delivery system is to achieve desired concentration of the drug in blood or tissue, which is therapeutically effective and non toxic for a prolonged period. Oral delivery of drugs is by far the most preferable route of drug delivery due to the ease of administration, patient compliance and flexibility in formulation etc. From immediate release to cite specific delivery, oral dosage forms have really progressed.
Tashakori-Sabzevar, Faezeh; Mohajeri, Seyed Ahmad
Recently, significant advances have been made in order to optimize drug delivery to ocular tissues. The main problems in ocular drug delivery are poor bioavailability and uncontrollable drug delivery of conventional ophthalmic preparations (e.g. eye drops). Hydrogels have been investigated since 1965 as new ocular drug delivery systems. Increase of hydrogel loading capacity, optimization of drug residence time on the ocular surface and biocompatibility with the eye tissue has been the main focus of previous studies. Molecular imprinting technology provided the opportunity to fulfill the above-mentioned objectives. Molecularly imprinted soft contact lenses (SCLs) have high potentials as novel drug delivery systems for the treatment of eye disorders. This technique is used for the preparation of polymers with specific binding sites for a template molecule. Previous studies indicated that molecular imprinting technology could be successfully applied for the preparation of SCLs as ocular drug delivery systems. Previous research, particularly in vivo studies, demonstrated that molecular imprinting is a versatile and effective method in optimizing the drug release behavior and enhancing the loading capacity of SCLs as new ocular drug delivery systems. This review highlights various potentials of molecularly imprinted contact lenses in enhancing the drug-loading capacity and controlling the drug release, compared to other ocular drug delivery systems. We have also studied the effects of contributing factors such as the type of comonomer, template/functional monomer molar ratio, crosslinker concentration in drug-loading capacity, and the release properties of molecularly imprinted hydrogels.
Vardakas, Konstantinos Z; Trigkidis, Kyriakos K; Boukouvala, Eleni; Falagas, Matthew E
Antibiotics have been the most important risk factor for Clostridium difficile infection (CDI). However, only data from non-randomised studies have been reviewed. We sought to evaluate the risk for development of CDI associated with the major antibiotic classes by analysing data from randomised controlled trials (RCTs). The PubMed, Cochrane and Scopus databases were searched and the references of selected RCTs were also hand-searched. Eligible studies should have compared only one antibiotic versus another administered systemically. Inclusion of studies comparing combinations of antibiotics was allowed only if the second antibiotic was the same or from the same class or if it was administered in a subset of the enrolled patients who were equally distributed in the two arms. Only a minority of the selected RCTs (79/1332; 5.9%) reported CDI episodes. Carbapenems were associated with more CDI episodes than fluoroquinolones [risk ratio (RR) = 2.44, 95% confidence interval (CI) 1.32-4.49] and cephalosporins (RR = 2.24, 95% CI 1.46-3.42), but not penicillins (RR = 2.53, 95% CI 0.87-7.41). Cephalosporins were associated with more CDIs than penicillins (RR = 2.36, 95% CI 1.32-4.23) and fluoroquinolones (RR = 2.84, 95% CI 1.60-5.06). There was no difference in CDI frequency between fluoroquinolones and penicillins (RR = 1.34, 95% CI 0.55-3.25). Finally, clindamycin was associated with more CDI episodes than cephalosporins and penicillins (RR = 3.92, 95% CI 1.15-13.43). In conclusion, data from RCTs showed that clindamycin and carbapenems were associated with more CDIs than other antibiotics. PMID:27216385
Li, Xiaojun; Peng, Longjun; Zhong, Kaiwen; Huang, Jianming
This article in view of the Logistic Delivery Management characteristic, analysis the logistic delivery management cannot satisfy requests rapid reaction and conformity transportation at present and so on. This article elaborated based on 3G (GIS, GPS, and GPRS) and RFID technology logistic delivery contents and so on management system, system design and architecture design, and its effective integration. The system design mentality uses the systems engineering method, follows the humanist idea, and embarks from user's demand, according to the user demand and the network request, divides according to the laminated structure into the decision-making strata, the service level, the management maintenance level and the technical support level 4 levels. The overall structural design including the system function structural design and the software system design, and take some province logistic delivery management system in management service as an example, introduced the design mentality and the application way.
... https://medlineplus.gov/news/fullstory_161230.html 2nd Antibiotic Halves C-Section Infection Rate: Study Two medications ... 29, 2016 (HealthDay News) -- Doctors routinely give an antibiotic before a cesarean-section, the surgical delivery of ...
The search for new materials for biomedical applications is extremely important. Here, we present results on the performance of a silver nanoparticles delivery system using natural rubber latex (NRL) as the polymeric matrix. Our aim was to obtain an optimized wound dressing by combining materials with potential healing action. The synthesis of silver nanoparticles and their characterization by UV–Vis spectroscopy, transmission electron microscopy, zeta potential, dynamic light scattering, and Fourier transform infrared spectroscopy (FTIR) are depicted. The NRL membranes are good matrix for silver nanoparticles and allow for their gradual release. The release of 30 nm silver nanoparticles by the NRL membranes depends on their mass percentage in NRL membranes. The total concentration of AgNP released by the NRL membranes was calculated. The AgNP attached to the cis-isoprene molecules in the NRL matrix remain attached to the membrane (∼0.1 % w/w). So, only the AgNP bound to the non-rubber molecules are released. FTIR spectra suggest that non-rubber molecules, like aminoacids and proteins, associated with the serum fraction of the NRL may be attached to the surfaces of the released nanoparticles, thereby increasing the release of such molecules. The released silver nanoparticles are sterically stabilized, more stable and well dispersed. Because the serum fraction of the NRL is responsible for the angiogenic properties of the matrix, the silver nanoparticles could increment the angiogenic properties of NRL. This biomaterial has desirable properties for the fabrication of a wound dressing with potential healing action, since it combines the angiogenic and antibacterial properties of the silver nanoparticles with the increased angiogenic properties of the NRL.Graphical AbstractThe AgNP attached to the cis-isoprene molecules remain in the NRL matrix and only the AgNP bound to the non-rubber molecules (NRL serum fraction) are released. The released AgNP are sterically
谢立信; 史伟云; 王治宇; 贝建中; 王身国
Objective To test the immunosuppressive effect of cyclosporine (Cs) in a polymer placed in the anterior chamber of corneal allograft recipients. Methods Wistar inbred rats with vascularized corneas were recipients of corneal allografts from Sprague-Dawley donor rats. Rats underwent penetrating keratoplasty and were divided randomly into four groups: untreated control animals (UCA); Cs-polymer anterior chamber recipients (CPA); co-polymer subconjunctival recipients (CPS); and Cs-olive oil drop recipients (COO). Grafts were examined by slit lamp every 3 days and clinical conditions were scored. Cs concentration in the aqueous humor was assayed at 1, 2, and 4 weeks. At 1, 2 and 4 weeks after transplantation, the operated eyes were collected for histopathological evaluation of the grafts. Results The median survival time of the allografts was 8.2±1.48 days for the UCA group, 11.4±2.50 days for the CPS group, and 17.0±2.00 days for the CPA group. There was a statistically significant difference (P<0.05) between survival time of the allografts in the animals of the CPA group compared to the other groups of graft recipients. Significantly higher concentrations of Cs were found in the eyes given an anterior chamber implant of Cs-polymer, compared to other treatment groups or untreated rats. A transient inflammatory response in the anterior chamber was observed in the CPA group. Conclusions Cs-polymer placed in the anterior chamber significantly prolongs corneal allograft survival time in a high risk corneal graft rejection model. This intraocular delivery system may be a valuable adjunct for the suppression of immune graft rejection.
Mahajan, Hitendra S; Gattani, Surendra G
Gellan gum microspheres of ondansetron hydrochloride, for intranasal delivery, were prepared to avoid the first pass metabolism as an alternative therapy to parentral, and to improve therapeutic efficiency in treatment of nausea and vomiting. The microspheres were prepared using conventional spray-drying method. The microspheres were evaluated for characteristics like particle size, incorporation efficiency, swelling ability, zeta potential, in-vitro mucoadhesion, thermal analysis, XRD study and in-vitro drug release. Treatment of in-vitro data to different kinetic equations indicated diffusion controlled drug delivery from gellan gum microspheres. The results of DSC and XRD studies revealed molecular amorphous dispersion of ondansetron into the gellan gum microspheres. PMID:19519195
GAŠPERLIN, MIRJANA; Gosenca, Mirjam; Bešter-Rogač, Marija
Liquid crystalline systems with a lamellar structure have been extensively studied as dermal delivery systems. Ascorbyl palmitate (AP) is one of the most studied and used ascorbic acid derivatives and is employed as an antioxidant to prevent skin aging. The aim of this study was to develop and characterize skin-compliant dermal delivery systems with a liquid crystalline structure for AP. First, a pseudoternary phase diagram was constructed using Tween 80/lecithin/isopropyl myristate/water at ...
N. Vishal Gupta; Shivakumar, H. G.
Background and the purpose of the study Many drugs which have narrow therapeutic window and are absorbed mainly in stomach have been developed as gastroretentive delivery system. Rosiglitazone maleate, an anti-diabetic, is highly unstable at basic pH and is extensively absorbed from the stomach. Hence there is a need to develop a gastroretentive system. In this study a superporous hydrogel was developed as a gastroretentive drug delivery system. Methods Chitosan/poly(vinyl alcohol) interpenet...
N. Vishal Gupta; Shivakumar, H. G.
"n "nBackground and the purpose of the study: Many drugs which have narrow therapeutic window and are absorbed mainly in stomach have been developed as gastroretentive delivery system. Rosiglitazone maleate, an anti-diabetic, is highly unstable at basic pH and is extensively absorbed from the stomach. Hence there is a need to develop a gastroretentive system. In this study a superporous hydrogel was developed as a gastroretentive drug delivery system. "nMethods: Chito...
Diana, Mark L
The purpose of this study is to explore the factors associated with outsourcing of information systems (IS) in hospital-based health care delivery systems, and to determine if there is a difference in IS outsourcing activity based on the strategic value of the outsourced functions. IS sourcing behavior is conceptualized as a case of vertical integration. A synthesis of strategic management theory (SMT) and transaction cost economics (TCE) serves as the theoretical framework. The sample consists of 1,365 hospital-based health care delivery systems that own 3,452 hospitals operating in 2004. The findings indicate that neither TCE nor SMT predicted outsourcing better than the other did. The findings also suggest that health care delivery system managers may not be considering significant factors when making sourcing decisions, including the relative strategic value of the functions they are outsourcing. It is consistent with previous literature to suggest that the high cost of IS may be the main factor driving the outsourcing decision.
Borgheti-Cardoso, Lívia Neves; Depieri, Lívia Vieira; Kooijmans, Sander A A; Diniz, Henrique; Calzzani, Ricardo Alexandre Junqueira; De Carvalho Vicentini, Fabiana Testa Moura; Van Der Meel, Roy; De Abreu Fantini, Márcia Carvalho; Iyomasa, Mamie Mizusaki; Schiffelers, Raymond M.; Bentley, Maria Vitória Lopes Badra; Schiffelers, Raymond
The development of delivery systems able to complex and release siRNA into the cytosol is essential for therapeutic use of siRNA. Among the delivery systems, local delivery has advantages over systemic administration. In this study, we developed and characterized non-viral carriers to deliver siRNA
... systems for the delivery of video programming. 63.02 Section 63.02 Telecommunication FEDERAL... systems for the delivery of video programming. (a) Any common carrier is exempt from the requirements of... with respect to the establishment or operation of a system for the delivery of video programming....
Broe, A; Pottegård, A; Lamont, Ronald Francis;
OBJECTIVE: The aim of this study was to describe the use of antibiotics in a national population-based cohort of pregnant Danish women between 2000 and 2010. DESIGN: Register-based, population-wide, cohort study. SETTING: Denmark, from 2000 to 2010. POPULATION: All pregnancies among Danish......, as well as intravaginally applied antibiotics, were analysed. Associations with demographic variables were assessed using multivariate analysis. MAIN OUTCOME MEASURES: Filled prescriptions for antibiotic drugs during pregnancy. RESULTS: We included 987 973 pregnancies in Denmark from 2000 to 2010; 38.......9% of women with a delivery and 14.8% of women with a miscarriage or termination of pregnancy had one or more antibiotic treatments during pregnancy. Systemic antibacterial drugs were the most frequently used drug group, with filled prescriptions for 33.4% of all deliveries and 12.6% of all abortions...
Van der Linden, P; Gilbart, E; Engelman, E; Schmartz, D; Vincent, J L
The present study tested the hypothesis that anesthetic agents can alter tissue O2 extraction capabilities in a dog model of progressive hemorrhage. After administration of pentobarbital sodium (25 mg/kg iv) and endotracheal intubation, the dogs were paralyzed with pancuronium bromide, ventilated with room air, and splenectomized. A total of 60 dogs were randomized in 10 groups of 6 dogs each. The first group served as control (C). A second group (P) received a continuous infusion of pentobarbital (4 mg.kg-2.h-2), which was started immediately after the bolus dose. Three groups received enflurane (E), halothane (HL), or isoflurane (I) at the end-tidal concentration of 0.7 minimum alveolar concentration (MAC). The sixth group received halothane at the end-tidal concentration of 1 MAC (HH). Two groups received intravenous alfentanil at relatively low dose (AL) or high dose (AH). The last two groups received intravenous ketamine at either relatively low dose (KL) or high dose (KH). In each group, O2 delivery (Do2) was progressively reduced by hemorrhage. At each step, systemic Do2 and O2 consumption (VO2) were measured separately and the critical point was determined from a plot of Vo2 vs. Do2. The critical O2 extraction ratio (OER) in the control group was 65.0 +/- 7.8%. OER was lower in all anesthetized groups (P, 44.3 +/- 11.8%; E, 47.0 +/- 7.7%; HL, 45.7 +/- 11.2%; I, 44.3 +/- 7.1%; HH, 33.7 +/- 6.0%; AL, 56.5 +/- 9.6%; AH, 43.5 +/- 5.9%; KH, 57.7 +/- 7.1%), except in the KL group (78.3 +/- 10.0%). The effects of halothane and alfentanil on critical OER were dose dependent (P less than 0.05), whereas critical OER was significantly lower in the KH than in the KL group. Moreover, the effects of anesthetic agents on critical Do2 appeared related to their effects on systemic vascular resistance. Anesthetic agents therefore alter O2 extraction by their peripheral vascular effects. However, ketamine, with its unique sympathetic stimulant properties, had a lesser effect
Prakash Chandra Pal
Full Text Available In this research article, we have described to establish a comparison between the solubility of the hydrochloride and non-hydrochlorideforms of ciprofloxacin and tetracycline in relevant solvents. For that purpose the solubility ofciprofloxacin and tetracycline were measured in water, methanol, propanol,and acetone, in the temperature range between 293.20 and 323.20 K for ciprofloxacin and between 288.20and 303.20 K for tetracycline. The solubility of the hydrochloride form in water is about 2 orders of magnitude higherthan those of the respective base forms. In acetone, we see the opposite effect. For methanol and propanolthe influence of the hydrochloride group of the antibiotic on the solubility in the alcohol is much smaller thanfor water and acetone. The experimental data was correlated with good results using two different activitycoefficient models, NRTL and UNIQUAC, with UNIQUAC giving better results, particularly for ciprofloxacin.The performance of COSMO-RS model to describe the studied systems was also evaluated.The dependence of these properties with temperature are shown. Theresults are interpreted in terms of solute-solvent interaction
Jiang, Feng; Liu, Biao; Lu, Jun; Li, Fangfei; Li, Defang; Liang, Chao; Dang, Lei; Liu, Jin; He, Bing; Badshah, Shaikh Atik; Lu, Cheng; He, Xiaojuan; Guo, Baosheng; Zhang, Xiao-Bing; Tan, Weihong; Lu, Aiping; Zhang, Ge
Aptamers, which can be screened via systematic evolution of ligands by exponential enrichment (SELEX), are superior ligands for molecular recognition due to their high selectivity and affinity. The interest in the use of aptamers as ligands for targeted drug delivery has been increasing due to their unique advantages. Based on their different compositions and preparation methods, aptamer-functionalized targeted drug delivery systems can be divided into two main categories: aptamer-small molecule conjugated systems and aptamer-nanomaterial conjugated systems. In this review, we not only summarize recent progress in aptamer selection and the application of aptamers in these targeted drug delivery systems but also discuss the advantages, challenges and new perspectives associated with these delivery systems.
Full Text Available Aptamers, which can be screened via systematic evolution of ligands by exponential enrichment (SELEX, are superior ligands for molecular recognition due to their high selectivity and affinity. The interest in the use of aptamers as ligands for targeted drug delivery has been increasing due to their unique advantages. Based on their different compositions and preparation methods, aptamer-functionalized targeted drug delivery systems can be divided into two main categories: aptamer-small molecule conjugated systems and aptamer-nanomaterial conjugated systems. In this review, we not only summarize recent progress in aptamer selection and the application of aptamers in these targeted drug delivery systems but also discuss the advantages, challenges and new perspectives associated with these delivery systems.
Ammar, H O; Ghorab, M; El-Nahhas, S A; Higazy, I M
Tenoxicam is a non steroidal anti-inflammatory drug (NSAID) widely used in the treatment of rheumatic diseases and characterized by its good efficacy and less side effects compared to other NSAIDs. Its oral administration is associated with severe side effects in the gastrointestinal tract. Transdermal drug delivery has been recognized as an alternative route to oral delivery. Proniosomes offer a versatile vesicle delivery concept with the potential for drug delivery via the transdermal route. In this study, different proniosomal gel bases were prepared, characterized by light microscopy, revealing vesicular structures, and assessed for their drug entrapment efficiency, stability, their effect on in vitro drug release and ex vivo drug permeation. The lecithin-free proniosomes prepared from Tween 20:cholesterol (9:1) proved to be stable with high entrapment and release efficiencies. The in vivo behaviour of this formula was studied on male rats and compared to that of the oral market product. The investigated tenoxicam loaded proniosomal formula proved to be non-irritant, with significantly higher anti-inflammatory and analgesic effects compared to that of the oral market tenoxicam tablets. PMID:21129461
Kreilgaard, Mads; Pedersen, E J; Jaroszewski, J W
), and to compare the drug delivery potential of microemulsions to conventional vehicles. Self-diffusion coefficients determined by pulsed-gradient spin-echo NMR spectroscopy and T(1) relaxation times were used to characterise the microemulsions. Transdermal flux of lidocaine and prilocaine hydrochloride through...
Xing-Hui SUN; Li TAN; Chun-Yang LI; Chang TONG; Jin FAN; Ping LI; Yun-Song ZHU
Recombinant proteins that combine different functions required for cell targeting and intracellular delivery of DNA present an attractive approach for the development of nonviral gene delivery vectors. Here, we described a novel protein termed ATF-lys10 which facilitated cell-specific gene transfer via receptor-mediated endocytosis. ATF-lys 10 was composed of the amino-terminal fragment of urokinase and ten lysines at the carboxyl terminus. Bacterially expressed ATF-lys 10 protein existed in soluble form, and had antigenicity of human urokinase. Purified ATF-lys 10 specifically bound to uPAR-expressing cells and formed protein-DNA complexes with plasmid pGL3-control. After neutralization of excess negative charge with poly-L-lysine, these complexes served as a specific gene delivery vector for uPAR-expressing cells. Lysosomotropic compounds, such as chloroquine, drastically increased the ATF-lysl0 mediated gene delivery efficiency. Our results suggest that the recombinant protein ATF-lys 10 with the properties of DNA binding and tumor cell targeting represents a promising method for gene transfer and expression in tumor cells.
Full Text Available Therapeutic genome editing technology has been widely used as a powerful tool for directly correcting genetic mutations in target pathological tissues and cells to cure of diseases. The modification of specific genomic sequences can be achieved by utilizing programmable nucleases, such as Meganucleases, zinc finger nucleases (ZFNs, transcription activator-like effector nucleases (TALENs, and the clustered regularly-interspaced short palindromic repeat-associated nuclease Cas9 (CRISPR/Cas9. However, given the properties, such as large size, negative charge, low membrane penetrating ability, as well as weak tolerance for serum, and low endosomal escape, of these nucleases genome editing cannot be successfully applied unless in vivo delivery of related programmable nucleases into target organisms or cells is achieved. Here, we look back at delivery strategies having been used in the in vivo delivery of three main genome editing nucleases, followed by methodologies currently undergoing testing in clinical trials, and potential delivery strategies provided by analyzing characteristics of nucleases and commonly used vectors.
Nicole L Fahrenfeld
Full Text Available Treated wastewater is increasingly being reused to achieve sustainable water management in arid regions. The objective of this study was to quantify the distribution of antibiotic resistance genes (ARGs in recycled water, particularly after it has passed through the distribution system, and to consider point-of-use implications for soil irrigation. Three separate reclaimed wastewater distribution systems in the western U.S. were examined. Quantitative polymerase chain reaction (qPCR was used to quantify ARGs corresponding to resistance to sulfonamides (sul1, sul2, macrolides (ermF, tetracycline (tet(A, tet(O, glycopeptides (vanA, and methicillin (mecA, in addition to genes present in waterborne pathogens Legionella pneumophila (Lmip, Escherichia coli (gadAB, and Pseudomonas aeruginosa (ecfx, gyrB. In a parallel lab study, the effect of irrigating an agricultural soil with secondary, chlorinated, or dechlorinated wastewater effluent was examined in batch microcosms. A broader range of ARGs were detected after the reclaimed water passed through the distribution systems, highlighting the importance of considering bacterial re-growth and the overall water quality at the point of use. Screening for pathogens with qPCR indicated presence of Lmip and gadAB genes, but not ecfx or gyrB. In the lab study, chlorination was observed to reduce 16S rRNA and sul2 gene copies in the wastewater effluent, while dechlorination had no apparent effect. ARGs levels did not change with time in soil slurries incubated after a single irrigation event with any of the effluents. However, when irrigated repeatedly with secondary wastewater effluent (not chlorinated or dechlorinated, elevated levels of sul1 and sul2 were observed. This study suggests that reclaimed water may be an important reservoir of ARGs, especially at the point of use, and that attention should be directed towards the fate of ARGs in irrigation water and the implications for human health.
Vibe, Carina Beatrice
Tuberculosis (TB), caused by Mycobacterium tuberculosis, has been treated with the same arsenal of antibiotics since the 1970 s; and with an estimated one third of the world s population latently infected at the moment, new regimens are sorely needed. Treatment remains lengthy and difficult, and inappropriate dosing or administration of drugs as well as patient non-compliance is contributing to the rising threat of multi-, extensively- and now totally- drug resistant TB. Should further expans...
Babu, Anish; Templeton, Amanda K; Munshi, Anupama; Ramesh, Rajagopal
Nanotechnology has enabled the development of novel therapeutic and diagnostic strategies, such as advances in targeted drug delivery systems, versatile molecular imaging modalities, stimulus responsive components for fabrication, and potential theranostic agents in cancer therapy. Nanoparticle modifications such as conjugation with polyethylene glycol have been used to increase the duration of nanoparticles in blood circulation and reduce renal clearance rates. Such modifications to nanoparticle fabrication are the initial steps toward clinical translation of nanoparticles. Additionally, the development of targeted drug delivery systems has substantially contributed to the therapeutic efficacy of anti-cancer drugs and cancer gene therapies compared with nontargeted conventional delivery systems. Although multifunctional nanoparticles offer numerous advantages, their complex nature imparts challenges in reproducibility and concerns of toxicity. A thorough understanding of the biological behavior of nanoparticle systems is strongly warranted prior to testing such systems in a clinical setting. Translation of novel nanodrug delivery systems from the bench to the bedside will require a collective approach. The present review focuses on recent research efforts citing relevant examples of advanced nanodrug delivery and imaging systems developed for cancer therapy. Additionally, this review highlights the newest technologies such as microfluidics and biomimetics that can aid in the development and speedy translation of nanodrug delivery systems to the clinic. PMID:24550101
Anselmo, Aaron C; Mitragotri, Samir
Drug delivery systems are widely researched and developed to improve the delivery of pharmaceutical compounds and molecules. The last few decades have seen a marked growth of the field fueled by increased number of researchers, research funding, venture capital and the number of start-ups. Collectively, the growth has led to novel systems that make use of micro/nano-particles, transdermal patches, inhalers, drug reservoir implants and antibody-drug conjugates. While the increased research activity is clearly an indication of proliferation of the field, clinical and commercial translation of early-stage research ideas is critically important for future growth and interest in the field. Here, we will highlight some of the examples of novel drug delivery systems that have undergone such translation. Specifically, we will discuss the developments, advantages, limitations and lessons learned from: (i) microparticle-based depot formulations, (ii) nanoparticle-based cancer drugs, (iii) transdermal systems, (iv) oral drug delivery systems, (v) pulmonary drug delivery, (vi) implants and (vii) antibody-drug conjugates. These systems have impacted treatment of many prevalent diseases including diabetes, cancer and cardiovascular diseases, among others. At the same time, these systems are integral and enabling components of products that collectively generate annual revenues exceeding US $100 billion. These examples provide strong evidence of the clinical and commercial impact of drug delivery systems.
Patel, Rashmin Bharatbhai; Patel, Mrunali Rashmin; Bhatt, Kashyap K; Patel, Bharat G; Gaikwad, Rajiv V
This study reports the development and evaluation of Carbamazepine (CMP)-loaded microemulsions (CMPME) for intranasal delivery in the treatment of epilepsy. The CMPME was prepared by the spontaneous emulsification method and characterized for physicochemical parameters. All formulations were radiolabeled with (99m)Tc (technetium) and biodistribution of CMP in the brain was investigated using Swiss albino rats. Brain scintigraphy imaging in rats was also performed to determine the uptake of the CMP into the brain. CMPME were found crystal clear and stable with average globule size of 34.11 ± 1.41 nm. (99m)Tc-labeled CMP solution (CMPS)/CMPME/CMP mucoadhesive microemulsion (CMPMME) were found to be stable and suitable for in vivo studies. Brain/blood ratio at all sampling points up to 8 h following intranasal administration of CMPMME compared to intravenous CMPME was found to be 2- to 3-fold higher signifying larger extent of distribution of the CMP in brain. Drug targeting efficiency and direct drug transport were found to be highest for CMPMME post-intranasal administration compared to intravenous CMP. Rat brain scintigraphy also demonstrated higher intranasal uptake of the CMP into the brain. This investigation demonstrates a prompt and larger extent of transport of CMP into the brain through intranasal CMPMME, which may prove beneficial for treatment of epilepsy.
TANG Xinzhong; SUN Hongmin; HU Xinyi
Data-delivery of agricultural information is a very tedious work, traditional data-delivery patterns and methods can not meet the requirements of the practical work. This paper provided the design idea and implement method for data-delivery system of agricultural information based on Web. Report and data will be separated in this system, and the person can change template and data at any time on demand. The problem that report template and data fixed together would be solved. The agricultural information resources sharing would be also implemented.
Biophysics and thermodynamics are considered as the scientific milestones for investigating the properties of materials. The relationship between the changes of temperature with the biophysical variables of biomaterials is important in the process of the development of drug delivery systems. Biophysics is a challenge sector of physics and should be used complementary with the biochemistry in order to discover new and promising technological platforms (i.e., drug delivery systems) and to disclose the 'silence functionality' of bio-inspired biological and artificial membranes. Thermal analysis and biophysical approaches in pharmaceuticals present reliable and versatile tools for their characterization and for the successful development of pharmaceutical products. The metastable phases of self-assembled nanostructures such as liposomes should be taken into consideration because they represent the thermal events can affect the functionality of advanced drug delivery nano systems. In conclusion, biophysics and thermodynamics are characterized as the building blocks for design and development of bio-inspired drug delivery systems.