scholarly journals EVALUATION OF STERCULIA FOETIDA L. GUM AS NATURAL BASED CONTROLLED RELEASE EXCIPIENT

2019 ◽  
Vol 57 (4) ◽  
pp. 428
Author(s):  
Vu Thi Hong Quan ◽  
Nguyen Thi Quan ◽  
Mai Thanh Phong ◽  
Le Thi Kim Phung
Keyword(s):  
Melting Point ◽  
Controlled Release ◽  
Drug Release ◽  
Physicochemical Properties ◽  
Electron Micrographs ◽  
Dosage Forms ◽  
Particle Sizes ◽  
Scanning Electron Micrographs ◽  
Scanning Electron

Therefore, the physicochemical properties of Sterculia foetida L. gum, including solubility, scanning electron micrographs, melting point, swelling index, pH, viscosity, loss on drying were determined. Furthermore, compressed tablets were successfully prepared for in vitro studies at many different particle sizes, concentrations of gum, rotational speeds and media in order to evaluate the effects of these parameters on the rate of drug release. Besides, SFG tablets were compared with the tablets prepared with Hydroxymethylcellulose E15. The findings indicated that Sterculia foetida L. gum exhibited an excellent potential in managed release dosage forms. 

Cultivation of Periodontal Ligament Fibroblasts on Dental Implant Materials and Enzymatically Debrided Teeth

1974 ◽  
Vol 53 (6) ◽  
pp. 1368-1376 ◽  
Author(s):  
T.K. Huard ◽  
L.F. Arnold ◽  
P. Baram
Keyword(s):  
Rhesus Monkey ◽  
Methyl Methacrylate ◽  
Dental Implant ◽  
Electron Micrographs ◽  
Periodontal Ligament ◽  
Scanning Electron Micrographs ◽  
Periodontal Ligament Fibroblasts ◽  
Implant Materials ◽  
Scanning Electron

Rhesus monkey periodontal ligament-derived fibroblasts were cultured on glass, Vitallium, poly(methyl methacrylate) and enzymatically debrided teeth. Scanning electron micrographs of these preparations and of the periodontal ligament surrounding normal and replanted teeth were compared. The fibroblasts cultured in vitro could organize on implant material and enzymatically debrided teeth to produce a network with fibers resembling those that are seen in the normal periodontal ligament.

scholarly journals The ALGINATE MICROSPHERES CONTAINING CURCUMIN: PREPARATION, CHARACTERIZATION, AND IN VITRO HUMAN HAEMOGLOBIN GLYCOSYLATION ASSAY

2019 ◽  
pp. 221-225
Author(s):  
KULKARNI AS ◽  
BHUJBAL SS
Keyword(s):  
Particle Size ◽  
Drug Release ◽  
Therapeutic Potential ◽  
Release Kinetics ◽  
Glycosylated Hemoglobin ◽  
Scanning Electron Micrographs ◽  
In Vitro Drug Release ◽  
Human Haemoglobin ◽  
Scanning Electron

Objective: The objective of the present study was to formulate, evaluate alginate microspheres of curcumin, and to investigate the inhibitory effect on glycosylated hemoglobin. Methods: All formulations were prepared by an ionotropic gelation technique using sodium alginate as a polymer and calcium chloride as a crosslinker in varying concentrations. The formulation batches (F1–F6) were evaluated for physical properties such as compatibility studies, percentage entrapment efficiency (%EE), microsphere yield, particle size, and polydispersity index. In vitro, drug release was studied and surface morphology was characterized by scanning electron microscopy. Results: The microspheres showed %EE, microsphere yield, particle size in the ranges of 44.86%–84.24%, 43.05%–81.4%, and 352–559 μm, respectively. In vitro, drug release and release kinetics showed that the developed curcumin microspheres system is a promising delivery system for controlled drug release. Scanning electron micrographs indicate porous and rough surface. The inhibitory properties of curcumin and microspheres (F4) on glycosylation formation were investigated in hemoglobin using quercetin as standard. The decreased in hemoglobin concentration after incubation of hemoglobin with a graded concentration of glucose over a specified time was used as an index for in vitro human hemoglobin glycosylation assay. Glycosylation inhibition was about 75% for standard quercetin, 60% for curcumin microspheres, and 38.74% for curcumin suspension occurred after 72 h. Conclusion: From these results, it can be concluded that curcumin in microsphere formulation has better therapeutic potential and could prove to be useful in the development of antidiabetic formulation.

scholarly journals Lysine bioavailability among 2 lipid-coated lysine products after exposure to silage1

2017 ◽  
Vol 1 (3) ◽  
pp. 311-319 ◽  
Author(s):  
J. N. Reiners ◽  
J. E. Held ◽  
C. L. Wright ◽  
Q. Qiao ◽  
G. D. Djira ◽  
...  
Keyword(s):  
Electron Micrographs ◽  
Corn Silage ◽  
Scanning Electron Micrographs ◽  
Visual Evaluation ◽  
Peripheral Surface ◽  
Physical And Chemical ◽  
Direct Measures ◽  
Scanning Electron

Abstract We conducted 2 experiments to determine lysine bioavailability from 2 lipid-coated lysine products. In an in vitro experiment we mixed each lipid-coated lysine product with either alfalfa- or corn-silage at different amounts of acidity. Scanning electron micrographs indicated that surface structure of each lipid-coated lysine particle was eroded after mixing with silage. Additionally, visual evaluation of scanning electron micrographs suggested that peripheral surface abrasion of lipid-coated lysine may be greater when lipid-coated lysine was mixed with alfalfa silage in comparison to corn silage. In a corresponding experiment, in vivo measures of lysine bioavailability to sheep from 2 lipid-coated lysine products and lysine-HCl were determined after mixing in corn silage. Plasma lysine concentrations increased linearly (P < 0.01) in response to abomasal lysine infusion indicating that our model was sensitive to increases in metabolizable lysine flow. Bioavailability of each lipid-coated lysine source and dietary lysine-HCl were calculated to be 23, 15, and 18%, respectively. Even though each dietary source of lysine increased plasma lysine, rates of increases in plasma lysine from one lipid-coated lysine source (linear; P = 0.20) and lysine-HCl (linear; P = 0.11) were not different from plasma lysine levels supported by diet alone. However, the rate of plasma lysine increase in response to lysine from the other lipid-coated lysine source was greater (P = 0.04) than plasma lysine from feed alone. Nonetheless, the rate of plasma lysine increase in response to lipid-coated lysine did not differ (P ≥ 0.70) from the rate of plasma lysine increase from lysine-HCl. Clearly, methods of manufacture, together with physical and chemical characteristics of diet, can impact amounts of metabolizable lysine provided from lipid-coated lysine products. Direct measures of lysine bioavailability from lipid-coated lysine products after mixing with diets should be based on measurements with the products treated similarly to the method of feeding.

Development and Evaluation of Controlled Release Mucoadhesive Tablets of Captopril

1970 ◽  
Vol 9 (3) ◽  
pp. 3318-3329
Author(s):  
Kranthi Kumar Kotta ◽  
L. Srinivas
Keyword(s):  
Controlled Release ◽  
Drug Release ◽  
Xanthan Gum ◽  
Diffusion Mechanism ◽  
Matrix Tablets ◽  
Fickian Diffusion ◽  
Content Uniformity ◽  
In Vitro Drug Release ◽  
Mucoadhesive Tablets

The present investigation focuses on the development of mucoadhesive tablets of captopril which are designed to prolong the gastric residence time after oral administration. Matrix tablets of captopril were formulated using four mucoadhesive polymers namely guar gum, xanthan gum, HPMC K4M and HPMC K15M and studied for parameters such as weight variation, thickness, hardness, content uniformity, swelling index, mucoadhesive force and in vitro drug release. Tablets formulated Xanthan gum or HPMC K4M with HPMC K15M provide slow release of captopril over period of 12 hr and were found suitable for maintenance portion of oral controlled release tablets. The cumulative % of drug release of formulation F9 and F10 were 90 and 92, respectively. In vitro release from these tablets was diffusion controlled and followed zero order kinetics. The ‘n’ values obtained from the pappas-karsemeyer equation suggested that all the formulation showed drug release by non-fickian diffusion mechanism. Tablets formulated Xanthan gum or HPMC K4M with HPMC K15M (1:1) were established to be the optimum formulation with optimum bioadhesive force, swelling index & desired invitro drug release. This product was further subjected to stability study, the results of which indicated no significant change with respect to Adhesive strength and in vitro drug release study.

Formulation Development and Characterization of controlled release core in cup matrix tablets of venlafaxine HCl

2020 ◽  
Vol 15 ◽  
Author(s):  
Balaji Maddiboyina ◽  
Vikas Jhawat ◽  
Gandhi Sivaraman ◽  
Om Prakash Sunnapu ◽  
Ramya Krishna Nakkala ◽  
...  
Keyword(s):  
Controlled Release ◽  
Drug Release ◽  
Release Rate ◽  
Zero Order ◽  
Water Soluble ◽  
Matrix Tablets ◽  
Drug Dissolution ◽  
Crystalline Cellulose ◽  
Hydrophobic Polymers

Background: Venlafaxine HCl is a selective serotonin reuptake inhibitor which is given in the treatment of depression. The delivery of the drug at a controlled rate can be of great importance for prolonged effect. Objective: The objective was to prepare and optimize the controlled release core in cup matrix tablet of venlafaxine HCl using the combination of hydrophilic and hydrophobic polymers to prolong the effect with rate controlled drug release. Methods: The controlled release core in cup matrix tablets of venlafaxine HCl were prepared using HPMC K5, K4, K15, HCO, IPA, aerosol, magnesium sterate, hydrogenated castor oil and micro crystalline cellulose PVOK-900 using wet granulation technique. Total ten formulations with varying concentrations of polymers were prepared and evaluated for different physicochemical parameters such FTIR analysis for drug identification, In-vitro drug dissolution study was performed to evaluate the amount of drug release in 24 hrs, drug release kinetics study was performed to fit the data in zero order, first order, Hixson–crowell and Higuchi equation to determine the mechanism of drug release and stability studies for 3 months as observed. Results: The results of hardness, thickness, weight variation, friability and drug content study were in acceptable range for all formulations. Based on the In vitro dissolution profile, formulation F-9 was considered to be the optimized extending the release of 98.32% of drug up to 24 hrs. The data fitting study showed that the optimized formulation followed the zero order release rate kinetics and also compared with innovator product (flavix XR) showed better drug release profile. Conclusion: The core-in-cup technology has a potential to control the release rate of freely water soluble drugs for single administration per day by optimization with combined use of hydrophilic and hydrophobic polymers.

scholarly journals Synthesis and Evaluation of AlgNa-g-poly(QCL-co-HEMA) Hydrogels as Platform for Chondrocyte Proliferation and Controlled Release of Betamethasone

2021 ◽  
Vol 22 (11) ◽  
pp. 5730
Author(s):  
Jomarien García-Couce ◽  
Marioly Vernhes ◽  
Nancy Bada ◽  
Lissette Agüero ◽  
Oscar Valdés ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Controlled Release ◽  
Biomedical Applications ◽  
Release Kinetics ◽  
Cell Types ◽  
Tissue Engineering Scaffolds ◽  
Almost All ◽  
Scanning Electron

Hydrogels obtained from combining different polymers are an interesting strategy for developing controlled release system platforms and tissue engineering scaffolds. In this study, the applicability of sodium alginate-g-(QCL-co-HEMA) hydrogels for these biomedical applications was evaluated. Hydrogels were synthesized by free-radical polymerization using a different concentration of the components. The hydrogels were characterized by Fourier transform-infrared spectroscopy, scanning electron microscopy, and a swelling degree. Betamethasone release as well as the in vitro cytocompatibility with chondrocytes and fibroblast cells were also evaluated. Scanning electron microscopy confirmed the porous surface morphology of the hydrogels in all cases. The swelling percent was determined at a different pH and was observed to be pH-sensitive. The controlled release behavior of betamethasone from the matrices was investigated in PBS media (pH = 7.4) and the drug was released in a controlled manner for up to 8 h. Human chondrocytes and fibroblasts were cultured on the hydrogels. The MTS assay showed that almost all hydrogels are cytocompatibles and an increase of proliferation in both cell types after one week of incubation was observed by the Live/Dead® assay. These results demonstrate that these hydrogels are attractive materials for pharmaceutical and biomedical applications due to their characteristics, their release kinetics, and biocompatibility.

A new genus and four new species of millipedes from Tasmania, Australia (Diplopoda: Polydesmida: Dalodesmidae), with notes on male leg setae in some Tasmanian dalodesmids

Zootaxa ◽  
2004 ◽  
Vol 558 (1) ◽  
pp. 1 ◽  
Author(s):  
ROBERT MESIBOV
Keyword(s):  
New Species ◽  
Electron Micrographs ◽  
Type Species ◽  
New Genus ◽  
Scanning Electron Micrographs ◽  
Scanning Electron

Bromodesmus catrionae n. gen., n. sp. (type species), B. militaris n. sp., B. riparius n. sp. and B. rufus n. sp. are described. The new genus is characterized by greatly reduced paranota and a gonopod telopodite expanded at the distal end into a posteriorly concave hood fringed with teeth; the hood partly protects a long, curved, acutely pointed solenomerite. Male leg setation in the type species of six Tasmanian dalodesmid genera is briefly discussed and illustrated with scanning electron micrographs. The sphaerotrichome shaft is sharply pointed in Atrophotergum; gently tapered in Dasystigma, Lissodesmus and Tasmanodesmus; expanded at the tip in Bromodesmus; and entirely absent in Gasterogramma. Tips of the setae forming the dense ventral brush on male podomeres are gently tapered in Dasystigma and Lissodesmus, truncated in Gasterogramma, expanded in Bromodesmus and forked in Tasmanodesmus.

The ultrastructure of the epidermis of the redia and cercaria of Parorchis acanthus, Nicoll. A study by scanning and transmission electron-microscopy

Parasitology ◽  
1971 ◽  
Vol 62 (3) ◽  
pp. 479-488 ◽  
Author(s):  
Gwendolen Rees
Keyword(s):  
Electron Micrographs ◽  
Technical Assistance ◽  
Ventral Surface ◽  
The Body ◽  
Muscle Fibres ◽  
Scanning Electron Micrographs ◽  
Large Area ◽  
Transmission Electron ◽  
Parorchis Acanthus ◽  
Scanning Electron

Scanning electron-micrographs have shown the covering of microvilli on the surface of the redia of Parorchis acanthus. In the contracted state the elongated microvilli with bulbous extremities seen in the surface grooves may be the result of compression. The surface of the epidermis of the cercaria is smooth on a large area of the ventral surface and lattice-like with microvilli, laterally, anteriorly, dorsally and on the tail. The spines on the body can be withdrawn into sheaths by the contraction of muscle fibres inserted into the basement lamina below each spine.I would like to express my sincere gratitude to Dr I. ap Gwynn of this department for preparing the scanning electron-micrographs and the School of Engineering Science, University of North Wales, Bangor for the use of their stereoscan. I should also like to thank Mr M. C. Bibby for technical assistance and Professor E. G. Gray and Dr W. Sinclair for assistance with the transmission electron-micrographs.

Aphid parasitoids infesting cotton, citrus, tobacco, and cereal crops in southeastern Europe: aphid-plant associations and keys

2005 ◽  
Vol 137 (5) ◽  
pp. 516-531 ◽  
Author(s):  
Nickolas G. Kavallieratos ◽  
Željko Tomanović ◽  
Christos G. Athanassiou ◽  
Petr Starý ◽  
Vladimir Žikić ◽  
...  
Keyword(s):  
Electron Micrographs ◽  
Separate Group ◽  
Cereal Crops ◽  
Scanning Electron Micrographs ◽  
Southeastern Europe ◽  
Line Drawings ◽  
Plant Associations ◽  
New Information ◽  
Aphid Parasitoids ◽  
Scanning Electron

AbstractWe present new information on the parasitoids (Hymenoptera: Braconidae: Aphidiinae) of aphids infesting cotton, tobacco, citrus, and cereal agroecosystems in southeastern Europe. Nineteen species are keyed and illustrated with scanning electron micrographs and line drawings. The aphidiines presented in this work have been identified from 18 aphid taxa. Furthermore, 96 original parasitoid–aphid–plant associations are presented. Cotton, tobacco, and citrus agroecosystems are connected through aphids and their parasitoids, whereas cereal agroecosystems represent a separate group of associations.

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