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1.
Recent Adv Food Nutr Agric ; 15(1): 2-12, 2024.
Article in English | MEDLINE | ID: mdl-38258781

ABSTRACT

Millets, small-seeded grasses, are gaining interest for their nutrition and health benefits. This abstract provides a comprehensive overview of millets' pharmacological activities, highlighting their rich bioactive compounds. These compounds, including phenolic compounds, flavonoids, and dietary fibers, contribute to antioxidant effects, safeguarding against chronic diseases. Millets also possess anti-inflammatory properties, potentially alleviating conditions, like arthritis and asthma. They show anti-carcinogenic potential, possibly preventing various cancers' development through mechanisms, like apoptosis induction and inhibiting tumor growth. Moreover, millets offer hypolipidemic and hypoglycemic effects, beneficial for managing conditions, such as dyslipidemia and diabetes. Their high dietary fiber and resistant starch content regulate blood lipids and glucose, reducing the cardiovascular risk. Additionally, millets act as antimicrobials, inhibiting pathogens and serving as natural alternatives to synthetic antimicrobials. They exhibit immunomodulatory effects, enhancing immune function and response. Overall, millets' pharmacological properties, including antioxidant, antiinflammatory, anti-carcinogenic, hypolipidemic, hypoglycemic, antimicrobial, and immunomodulatory traits, position them as functional foods with varied health benefits. Further research can integrate millets into preventive and therapeutic approaches for diverse diseases.


Subject(s)
Dietary Supplements , Humans , Functional Food , Antioxidants/pharmacology , Antioxidants/therapeutic use , Animals , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/therapeutic use , Dietary Fiber/therapeutic use , Hypoglycemic Agents/therapeutic use , Hypoglycemic Agents/pharmacology
2.
AAPS PharmSciTech ; 19(8): 3681-3686, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30280349

ABSTRACT

Biological products such as protein-based biopharmaceuticals are playing an important role in the healthcare and pharmaceutical industry. The interaction between biological products and packaging materials has become the focus of many studies since it can reduce the effectiveness of biological products. These interactions are heavily influenced by the surface properties and physicochemical nature of the therapeutic agents and the packaging materials. Therefore, it is critical to understand the interactions between packaging materials and biological products in order to design biocompatible packaging materials and develop approaches to minimize adverse interactions. We describe the interactions that occur when using several common packaging materials, including glass and polymer. We discuss the interaction between these materials and biological products such as blood, blood derivatives, recombinant proteins, monoclonal antibodies, and gene therapeutics. We also summarize approaches for overcoming these interactions. Understanding the interactions between biological materials and packaging materials is critical for the development of novel packaging materials that improve the safety of pharmaceutical products.


Subject(s)
Biological Products/chemistry , Product Packaging , Drug Industry , Glass/chemistry , Polymers/chemistry
3.
Pharmacogn Rev ; 11(22): 141-144, 2017.
Article in English | MEDLINE | ID: mdl-28989249

ABSTRACT

Holarrhena antidysenterica (L.) Wall. ex A. DC. is a medicinal plant abundantly found in India. Its uses are mentioned in the classical Ayurvedic literature and by many folklore claims. The plant is also of extreme economic importance. Its seeds are mainly used as an antidiabetic remedy. All pharmacological and toxicological aspects of this plant are discussed in this review.

4.
Eur J Pharm Biopharm ; 119: 81-90, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28596037

ABSTRACT

The main objective of this novel study was to develop chlorpheniramine maleate orally disintegrating films (ODF) using hot-melt extrusion technology and evaluate the characteristics of the formulation using in vitro and in vivo methods. Modified starch with glycerol was used as a polymer matrix for melt extrusion. Sweetening and saliva-simulating agents were incorporated to improve palatability and lower the disintegration time of film formulations. A standard screw configuration was applied, and the last zone of the barrel was opened to discharge water vapors, which helped to manufacture non-sticky, clear, and uniform films. The film formulations demonstrated rapid disintegration times (6-11s) and more than 95% dissolution in 5min. In addition, the films had characteristic mechanical properties that were helpful in handling and storage. An animal model was employed to determine the taste masking of melt-extruded films. The lead film formulation was subjected to a human panel for evaluation of extent of taste masking and disintegration.


Subject(s)
Anti-Allergic Agents/administration & dosage , Chlorpheniramine/administration & dosage , Drug Carriers/administration & dosage , Hot Temperature , Technology, Pharmaceutical/methods , Administration, Oral , Adolescent , Adult , Animals , Anti-Allergic Agents/chemical synthesis , Anti-Allergic Agents/metabolism , Chlorpheniramine/chemical synthesis , Chlorpheniramine/metabolism , Drug Carriers/chemical synthesis , Drug Carriers/metabolism , Drug Evaluation, Preclinical/methods , Female , Humans , Male , Rats , Rats, Sprague-Dawley , Solubility , Taste Perception/drug effects , Taste Perception/physiology , X-Ray Diffraction/methods , Young Adult
5.
Int J Pharm ; 487(1-2): 167-76, 2015 Jun 20.
Article in English | MEDLINE | ID: mdl-25888797

ABSTRACT

The objective of this study was to develop caffeine citrate orally disintegrating tablet (ODT) formulations utilizing hot-melt extrusion technology and evaluate the ability of the formulation composition to mask the unpleasant bitter taste of the drug using in vitro and in vivo methods. Ethylcellulose, along with a suitable plasticizer, was used as a polymeric carrier. Pore forming agents were incorporated into the extruded matrix to enhance drug release. A modified screw configuration was applied to improve the extrusion processability and to preserve the crystallinity of the API. The milled extrudates were subjected to dissolution testing in an artificial salivary fluid and investigations using e-tongue, to assess the extent of masking of bitter taste of the API. There was an insignificant amount of drug released from the formulation in the salivary medium while over 80% of drug released within 30 min in 0.1N HCl. ODTs were also developed with the extrudate mixed with mannitol and crospovidone. The quality properties such as friability and disintegration time of the ODTs met the USP specifications. The lead extrudate formulations and the ODTs prepared using this formulation were subjected to human gustatory evaluation. The formulations were found to mask the unpleasant taste of caffeine citrate significantly.


Subject(s)
Caffeine/adverse effects , Citrates/adverse effects , Taste/drug effects , Caffeine/chemistry , Cellulose/analogs & derivatives , Chemistry, Pharmaceutical , Citrates/chemistry , Drug Carriers , Drug Compounding , Humans , Plasticizers , Solubility , Tablets , Taste Perception
6.
AAPS PharmSciTech ; 16(2): 444-54, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25361900

ABSTRACT

The objective of the present study was to investigate the effects of processing variables and formulation factors on the characteristics of hot-melt extrudates containing a copolymer (Kollidon® VA 64). Nifedipine was used as a model drug in all of the extrudates. Differential scanning calorimetry (DSC) was utilized on the physical mixtures and melts of varying drug-polymer concentrations to study their miscibility. The drug-polymer binary mixtures were studied for powder flow, drug release, and physical and chemical stabilities. The effects of moisture absorption on the content uniformity of the extrudates were also studied. Processing the materials at lower barrel temperatures (115-135°C) and higher screw speeds (50-100 rpm) exhibited higher post-processing drug content (~99-100%). DSC and X-ray diffraction studies confirmed that melt extrusion of drug-polymer mixtures led to the formation of solid dispersions. Interestingly, the extrusion process also enhanced the powder flow characteristics, which occurred irrespective of the drug load (up to 40% w/w). Moreover, the content uniformity of the extrudates, unlike the physical mixtures, was not sensitive to the amount of moisture absorbed. The extrusion conditions did not influence drug release from the extrudates; however, release was greatly affected by the drug loading. Additionally, the drug release from the physical mixture of nifedipine-Kollidon® VA 64 was significantly different when compared to the corresponding extrudates (f2 = 36.70). The extrudates exhibited both physical and chemical stabilities throughout the period of study. Overall, hot-melt extrusion technology in combination with Kollidon® VA 64 produced extrudates capable of higher drug loading, with enhanced flow characteristics, and excellent stability.


Subject(s)
Pyrrolidines/chemistry , Vinyl Compounds/chemistry , Chemistry, Pharmaceutical/methods , Drug Carriers/chemistry , Drug Stability , Hot Temperature , Polymers/chemistry , Solubility , Technology, Pharmaceutical/methods
7.
Environ Sci Technol ; 49(4): 2523-31, 2015 Feb 17.
Article in English | MEDLINE | ID: mdl-25546702

ABSTRACT

The link between the nitrogen and one-carbon cycles forms the metabolic basis for energy and biomass synthesis in autotrophic nitrifying organisms, which in turn are crucial players in engineered nitrogen removal processes. To understand how autotrophic nitrifying organisms respond to inorganic carbon (IC) conditions that could be encountered in engineered partially nitrifying systems, we investigated the response of one of the most extensively studied model ammonia oxidizing bacteria, Nitrosomonas europaea (ATCC19718), to three IC availability conditions: excess gaseous and excess ionic IC supply (40× stoichiometric requirement), excess gaseous IC supply (4× stoichiometric requirement in gaseous form only), and limiting IC supply (0.25× stoichiometric requirement). We found that, when switching from excess gaseous and excess ionic IC supply to excess gaseous IC supply, N. europaea chemostat cultures demonstrated an acclimation period that was characterized by transient decreases in the ammonia removal efficiency and transient peaks in the specific oxygen uptake rate. Limiting IC supply led to permanent reactor failures (characterized by biomass washout and failure of ammonia removal) that were preceded by similar decreases in the ammonia removal efficiency and peaks in the specific oxygen uptake rate. Notably, both excess gaseous IC supply and limiting IC supply elicited a previously undocumented increase in nitric and nitrous oxide emissions. Further, gene expression patterns suggested that excess gaseous IC supply and limiting IC supply led to consistent up-regulation of ammonia respiration genes and carbon assimilation genes. Under these conditions, interrogation of the N. europaea proteome revealed increased levels of carbon fixation and transport proteins and decreased levels of ammonia oxidation proteins (active in energy synthesis pathways). Together, the results indicated that N. europaea mobilized enhanced IC scavenging pathways for biosynthesis and turned down respiratory pathways for energy synthesis, when challenged with excess gaseous IC supply and limiting IC supply.


Subject(s)
Carbon/metabolism , Nitrosomonas europaea/metabolism , Ammonia/metabolism , Nitrogen/metabolism , Nitrous Oxide/metabolism
8.
Skin Pharmacol Physiol ; 26(4-6): 331-42, 2013.
Article in English | MEDLINE | ID: mdl-23921120

ABSTRACT

Despite its remarkable barrier function, the skin remains an attractive site for systemic drug delivery given its easy accessibility, large surface area and the possibility to bypass the gastrointestinal tract and the liver and so modify drug absorption kinetics. The pioneering work of Scheuplein, Higuchi and others in the 1960s helped to explain the processes involved in passive percutaneous absorption and led to the development of mathematical models to describe transdermal drug delivery. The intervening years have seen these theories turned to practice and a significant number of transdermal systems are now available including some that employ active drug delivery. This review briefly discusses the evolution of transdermal therapeutic systems over the years and the potential of newer transdermal technologies to deliver hydrophilic drugs and macromolecules through the skin.


Subject(s)
Drug Delivery Systems/trends , Models, Theoretical , Skin Absorption , Administration, Cutaneous , Drug Design , Humans , Hydrophobic and Hydrophilic Interactions , Macromolecular Substances/administration & dosage , Macromolecular Substances/chemistry , Macromolecular Substances/pharmacokinetics , Pharmaceutical Preparations/administration & dosage , Pharmaceutical Preparations/chemistry , Pharmaceutical Preparations/metabolism , Skin/metabolism , Technology, Pharmaceutical/trends
9.
J Clin Invest ; 123(5): 1964-75, 2013 May.
Article in English | MEDLINE | ID: mdl-23585478

ABSTRACT

Giant axonal neuropathy (GAN) is an early-onset neurological disorder caused by mutations in the GAN gene (encoding for gigaxonin), which is predicted to be an E3 ligase adaptor. In GAN, aggregates of intermediate filaments (IFs) represent the main pathological feature detected in neurons and other cell types, including patients' dermal fibroblasts. The molecular mechanism by which these mutations cause IFs to aggregate is unknown. Using fibroblasts from patients and normal individuals, as well as Gan-/- mice, we demonstrated that gigaxonin was responsible for the degradation of vimentin IFs. Gigaxonin was similarly involved in the degradation of peripherin and neurofilament IF proteins in neurons. Furthermore, proteasome inhibition by MG-132 reversed the clearance of IF proteins in cells overexpressing gigaxonin, demonstrating the involvement of the proteasomal degradation pathway. Together, these findings identify gigaxonin as a major factor in the degradation of cytoskeletal IFs and provide an explanation for IF aggregate accumulation, the subcellular hallmark of this devastating human disease.


Subject(s)
Cytoskeletal Proteins/genetics , Giant Axonal Neuropathy/pathology , Intermediate Filament Proteins/metabolism , Mutation , Animals , Cytoskeletal Proteins/metabolism , Cytoskeleton/metabolism , Enzyme-Linked Immunosorbent Assay , Fibroblasts/cytology , Fibroblasts/metabolism , HEK293 Cells , Humans , Leupeptins/pharmacology , Mice , Mice, Transgenic , Microscopy, Fluorescence , NIH 3T3 Cells , Neurons/metabolism , Proteasome Inhibitors/pharmacology , RNA, Messenger/metabolism , Sequence Analysis, DNA , Ubiquitin-Protein Ligases/metabolism , Vimentin/metabolism
11.
Water Res ; 46(9): 2937-46, 2012 Jun 01.
Article in English | MEDLINE | ID: mdl-22494493

ABSTRACT

The presence of micropollutants can be a concern for land application of biosolids. Of particular interest are nonylphenol diethoxylate (NP(2)EO), nonylphenol monoethoxylate (NP(1)EO), and nonylphenol (NP), collectively referred to as NPE, which accumulate in anaerobically digested biosolids and are subject to regulation based on the environmental risks associated with them. Because biosolids are a valuable nutrient resource, it is essential that we understand how various treatment processes impact the fate of NPE in biosolids. Thermal hydrolysis (TH) coupled with mesophilic anaerobic digestion (MAD) is an advanced digestion process that destroys pathogens in biosolids and increases methane yields and volatile solids destruction. We investigated the impact of thermal hydrolysis pretreatment on the subsequent biodegradation of NPE in digested biosolids. Biosolids were treated with TH, anaerobic digestion, and aerobic digestion in laboratory-scale reactors, and NPE were analyzed in the influent and effluent of the digesters. NP(2)EO and NP(1)EO have been observed to degrade to the more estrogenic NP under anaerobic conditions; therefore, changes in the ratio of NP:NPE were of interest. The increase in NP:NPE following MAD was 56%; the average increase of this ratio in four sets of TH-MAD samples, however, was only 24.6 ± 3.1%. In addition, TH experiments performed in pure water verified that, during TH, the high temperature and pressure alone did not directly destroy NPE; TH experiments with NP added to sludge also showed that NP was not destroyed by the high temperature and pressure of TH when in a more complex sludge matrix. The post-aerobic digestion phases removed NPE, regardless of whether TH pretreatment occurred. This research indicates that changes in biosolids processing can have impacts beyond just gas production and solids destruction.


Subject(s)
Phenols/chemistry , Sewage , Anaerobiosis , Chromatography, High Pressure Liquid , Estrogens/chemistry , Hydrolysis , Spectrometry, Mass, Electrospray Ionization , Water Pollutants/chemistry
12.
J Struct Biol ; 177(1): 14-23, 2012 Jan.
Article in English | MEDLINE | ID: mdl-22120848

ABSTRACT

Although intermediate filaments are one of three major cytoskeletal systems of vertebrate cells, they remain the least understood with respect to their structure and function. This is due in part to the fact that they are encoded by a large gene family which is developmentally regulated in a cell and tissue type specific fashion. This article is in honor of Ueli Aebi. It highlights the studies on IF that have been carried out by our laboratory for more than 40 years. Many of our advances in understanding IF are based on conversations with Ueli which have taken place during adventurous and sometimes dangerous hiking and biking trips throughout the world.


Subject(s)
Intermediate Filaments/metabolism , Intermediate Filaments/ultrastructure , Animals , Cell Movement , Cytoskeleton/metabolism , Cytoskeleton/ultrastructure , Keratins/metabolism , Keratins/ultrastructure , Phosphorylation , Vimentin/metabolism , Vimentin/ultrastructure
13.
Circ Arrhythm Electrophysiol ; 4(3): 388-96, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21421805

ABSTRACT

BACKGROUND: Atrial fibrillation (AF) is commonly associated with congestive heart failure (CHF). The autonomic nervous system is involved in the pathogenesis of both AF and CHF. We examined the role of autonomic remodeling in contributing to AF substrate in CHF. METHODS AND RESULTS: Electrophysiological mapping was performed in the pulmonary veins and left atrium in 38 rapid ventricular-paced dogs (CHF group) and 39 control dogs under the following conditions: vagal stimulation, isoproterenol infusion, ß-adrenergic blockade, acetylcholinesterase (AChE) inhibition (physostigmine), parasympathetic blockade, and double autonomic blockade. Explanted atria were examined for nerve density/distribution, muscarinic receptor and ß-adrenergic receptor densities, and AChE activity. In CHF dogs, there was an increase in nerve bundle size, parasympathetic fibers/bundle, and density of sympathetic fibrils and cardiac ganglia, all preferentially in the posterior left atrium/pulmonary veins. Sympathetic hyperinnervation was accompanied by increases in ß(1)-adrenergic receptor R density and in sympathetic effect on effective refractory periods and activation direction. ß-Adrenergic blockade slowed AF dominant frequency. Parasympathetic remodeling was more complex, resulting in increased AChE activity, unchanged muscarinic receptor density, unchanged parasympathetic effect on activation direction and decreased effect of vagal stimulation on effective refractory period (restored by AChE inhibition). Parasympathetic blockade markedly decreased AF duration. CONCLUSIONS: In this heart failure model, autonomic and electrophysiological remodeling occurs, involving the posterior left atrium and pulmonary veins. Despite synaptic compensation, parasympathetic hyperinnervation contributes significantly to AF maintenance. Parasympathetic and/or sympathetic signaling may be possible therapeutic targets for AF in CHF.


Subject(s)
Atrial Fibrillation/physiopathology , Autonomic Nervous System/physiopathology , Body Surface Potential Mapping/methods , Heart Atria/physiopathology , Heart Failure/physiopathology , Pulmonary Veins/physiopathology , Animals , Atrial Fibrillation/etiology , Cardiac Pacing, Artificial , Disease Models, Animal , Dogs , Heart Failure/complications , Pulmonary Veins/innervation
14.
Mol Biol Cell ; 22(8): 1274-89, 2011 Apr 15.
Article in English | MEDLINE | ID: mdl-21346197

ABSTRACT

Vimentin intermediate filaments (VIF) extend throughout the rear and perinuclear regions of migrating fibroblasts, but only nonfilamentous vimentin particles are present in lamellipodial regions. In contrast, VIF networks extend to the entire cell periphery in serum-starved or nonmotile fibroblasts. Upon serum addition or activation of Rac1, VIF are rapidly phosphorylated at Ser-38, a p21-activated kinase phosphorylation site. This phosphorylation of vimentin is coincident with VIF disassembly at and retraction from the cell surface where lamellipodia form. Furthermore, local induction of photoactivatable Rac1 or the microinjection of a vimentin mimetic peptide (2B2) disassemble VIF at sites where lamellipodia subsequently form. When vimentin organization is disrupted by a dominant-negative mutant or by silencing, there is a loss of polarity, as evidenced by the formation of lamellipodia encircling the entire cell, as well as reduced cell motility. These findings demonstrate an antagonistic relationship between VIF and the formation of lamellipodia.


Subject(s)
Cell Movement , Neuropeptides/metabolism , Peptide Fragments/metabolism , Pseudopodia/metabolism , Vimentin/metabolism , rac GTP-Binding Proteins/metabolism , Animals , Cell Polarity , Escherichia coli , Gene Expression , Gene Silencing , Humans , Intermediate Filaments/metabolism , Mice , Mice, Knockout , Microinjections , NIH 3T3 Cells , Neuropeptides/genetics , Peptide Fragments/genetics , Phosphorylation , Pseudopodia/genetics , RNA, Small Interfering/metabolism , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism , Serine/metabolism , Serum/metabolism , Vimentin/genetics , p21-Activated Kinases/genetics , p21-Activated Kinases/metabolism , rac GTP-Binding Proteins/genetics , rac1 GTP-Binding Protein
15.
Complement Ther Clin Pract ; 17(1): 9-12, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21168107

ABSTRACT

AIM: The primary aim was to study the effect of naturopathy and yoga interventions in treatment of mild to moderate hypertension. DESIGN: The variables of interest were measured at the beginning and end of the intervention using a pre-post design. SETTING: The study was conducted by INYS medical research society in Jindal Nature Cure Institute, Bangalore. SUBJECTS: A total of 104 subjects, already diagnosed with mild to moderate hypertension and on treatment with antihypertensive medicines were included in study. INTERVENTIONS: The intervention consisted of various inpatient administration of different naturopathy treatments, yoga therapies, low calorie and low sodium diet for 21 days. Antihypertensive medicines were withdrawn for some patients in one week based upon response to the treatment. OUTCOME MEASURES: The outcome measures were values of diastolic and systolic blood pressure and body weight. Subjects were followed for a period of one year after every 3 months. RESULTS: After starting nonpharmacological approach of naturopathy and yoga, Systolic blood pressure came down from mean of 139.6 to 129.6 where as it came down from 91.2 to 86.1 for diastolic blood pressure. At the same time favorable effect was also seen in other variables like lipid profile and body weight. At the end of one year out of 57 patients who came for follow-up, 14 cases were found to have blood pressure within normal ranges without any medication over the previous 12 months. CONCLUSION: Naturopathy and yoga therapy can be considered as a valuable nonpharmacological approach in treatment of hypertension.


Subject(s)
Blood Pressure , Hypertension/therapy , Lipids/blood , Naturopathy , Yoga , Antihypertensive Agents/therapeutic use , Body Weight , Caloric Restriction , Diet, Sodium-Restricted , Humans , Hypertension/blood , Hypertension/physiopathology , Life Style , Treatment Outcome
17.
J Tissue Eng Regen Med ; 4(8): 600-10, 2010 Dec.
Article in English | MEDLINE | ID: mdl-20222010

ABSTRACT

The mechanism for stem cell-mediated improvement following acute myocardial infarction has been actively debated. We support hypotheses that the stem cell effect is primarily paracrine factor-linked. We used a heparin-presenting injectable nanofibre network to bind and deliver paracrine factors derived from hypoxic conditioned stem cell media to mimic this stem cell paracrine effect. Our self-assembling peptide nanofibres presenting heparin were capable of binding paracrine factors from a medium phase. When these factor-loaded materials were injected into the heart following coronary artery ligation in a mouse ischaemia-reperfusion model of acute myocardial infarction, we found significant preservation of haemodynamic function. Through media manipulation, we were able to determine that crucial factors are primarily < 30 kDa and primarily heparin-binding. Using recombinant VEGF- and bFGF-loaded nanofibre networks, the effect observed with conditioned media was recapitulated. When evaluated in another disease model, a chronic rat ischaemic hind limb, our factor-loaded materials contributed to extensive limb revascularization. These experiments demonstrate the potency of the paracrine effect associated with stem cell therapies and the potential of a biomaterial to bind and deliver these factors, pointing to a potential therapy based on synthetic materials and recombinant factors as an acellular therapy.


Subject(s)
Cardiovascular Diseases/therapy , Heparin/pharmacology , Mesenchymal Stem Cells/drug effects , Mesenchymal Stem Cells/metabolism , Nanofibers/chemistry , Paracrine Communication/drug effects , Animals , Culture Media, Conditioned/pharmacology , Fibroblast Growth Factor 2/metabolism , Heart Ventricles/physiopathology , Hindlimb/blood supply , Hindlimb/drug effects , Hindlimb/pathology , Mesenchymal Stem Cell Transplantation , Mice , Molecular Weight , Myocardial Contraction/drug effects , Myocardial Infarction/physiopathology , Peptides/chemistry , Peptides/metabolism , Rats , Vascular Endothelial Growth Factor A/metabolism
18.
Curr Drug Deliv ; 7(2): 125-36, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20158490

ABSTRACT

The stratum corneum (SC) is a primary rate limiting barrier to permeation of drug molecules through the skin. Small molecular weight lipophilic drugs that are effective at low doses can be effectively delivered by passive transdermal delivery. The SC does not permit passage of polar/hydrophilic and macromolecules. Passive and physical penetration enhancements strategies are used to overcome this barrier property of the SC. Passive penetration enhancement techniques include use of supersaturated solutions and penetration enhancers. In general, the drug delivery potential of chemical modalities is limited. Therefore, physical permeation enhancement techniques gained a lot of focus in the recent past. Physical penetration enhancement techniques include iontophoresis, electroporation and sonophoresis. Electroporation utilizes high voltage pulses that are applied for a very short time to permeabilize the skin to facilitate transport of macromolecules and hydrophilic compounds. Several drugs have been administered via this system successfully. This review presents an overview of in-vitro and in-vivo studies demonstrating therapeutic benefits offered by electroporation assisted permeation. Factors affecting electroporation, synergism between electroporation and other penetration enhancing strategies are also discussed.


Subject(s)
Administration, Cutaneous , Drug Delivery Systems/methods , Electroporation/methods , Nonprescription Drugs/administration & dosage , Prescription Drugs/administration & dosage , Animals , Drug Delivery Systems/adverse effects , Electroporation/trends , Humans , Skin Absorption/physiology
19.
Water Sci Technol ; 60(10): 2647-57, 2009.
Article in English | MEDLINE | ID: mdl-19923771

ABSTRACT

The effectiveness of four different electron donors, specifically methanol, ethanol, glycerol, and sulfide (added as Na(2)S), were evaluated in post-denitrifying bench-scale moving bed biofilm reactors (MBBRs). With the requirement for more wastewater treatment plants to reach effluent total nitrogen levels approaching 3 mg/L, alternative electron donors could promote more rapid MBBR startup/acclimation times and increased cold weather denitrification rates compared to methanol, which has been most commonly used for post-denitrification processes due to low cost and effectiveness. While the application of alternative substrates in suspended growth processes has been studied extensively, fixed film post denitrification processes have been designed to use primarily low yield substrates like methanol. Bench-scale MBBRs were operated continuously at 12 degrees Celsius, and performance was monitored by weekly sampling and insitu batch profile testing. Ethanol and glycerol, though visually exhibited much higher biofilm carrier biomass content, performed better than methanol in terms of removal rate (0.9 and 1.0 versus 0.6 g N/m(2)/day, respectively.) Maximum denitrification rate measurements from profile testing suggested that ethanol and glycerol (2.2 and 1.9 g N/m(2)/day, respectively) exhibited rates that were four times that of methanol (0.49 g N/m(2)/day.) Sulfide also performed much better than either of the other three electron donors with maximum rates at 3.6 g N/m(2)/day and with yield (COD/NO(3)-N) that was similar to or slightly less than that of methanol.


Subject(s)
Bacteria/metabolism , Biofilms/growth & development , Electron Transport , Biodegradation, Environmental , Bioreactors , Carbon/metabolism , Electrons , Nitrites/metabolism , Time Factors , Waste Disposal, Fluid/methods , Water Pollutants, Chemical , Water Purification/methods
20.
Biochemistry ; 48(12): 2654-60, 2009 Mar 31.
Article in English | MEDLINE | ID: mdl-19222223

ABSTRACT

Transglutaminases (TGs) are known to exhibit remarkable specificities not only for the Q (or Gln) sites but also for the K (or Lys) sites of proteins with which they react. To gain further insight into K-site specificity, we examined the reactions of dansyl-epsilon-aminocaproyl-GlnGlnIleVal with three chemically and structurally well-characterized proteins (bovine pancreatic ribonuclease A, bovine pancreatic trypsin inhibitor, and chicken egg white lysozyme), as catalyzed by TG2, a biologically important post-translational enzyme. The substrates represent a total of 20 potential surface sites for acylation by the fluorescent Gln probe, yet only two of the lysine side chains reacted with TG2. While the K1 site of ribonuclease and the K15 site of the trypsin inhibitor could be readily acylated by the enzyme, none of the lysines in lysozyme were modified. The findings lead us to suggest that the selection of lysine residues by TG2 is not encoded in the primary amino acid sequence surrounding the target side chain but depends primarily on its being positioned in an accessible segment of the protein structure.


Subject(s)
Lysine/metabolism , Protein Processing, Post-Translational , Transglutaminases/metabolism , Acylation , Animals , Binding Sites , Cattle , Models, Molecular , Protein Conformation , Substrate Specificity
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