scholarly journals Injectable Thermosensitive Formulation Based on Polyurethane Hydrogel/Mesoporous Glasses for Sustained Co-Delivery of Functional Ions and Drugs

Pharmaceutics ◽  
2019 ◽  
Vol 11 (10) ◽  
pp. 501 ◽  
Author(s):  
Monica Boffito ◽  
Carlotta Pontremoli ◽  
Sonia Fiorilli ◽  
Rossella Laurano ◽  
Gianluca Ciardelli ◽  
...  
Keyword(s):  
Therapeutic Agents ◽  
Chemical Degradation ◽  
Burst Release ◽  
Injectable Hydrogels ◽  
Micro Particles ◽  
Custom Made ◽  
Thermosensitive Hydrogels ◽  
Polyurethane Hydrogel ◽  
Over Time ◽  
Incipient Wetness Method

Mini-invasively injectable hydrogels are widely attracting interest as smart tools for the co-delivery of therapeutic agents targeting different aspects of tissue/organ healing (e.g., neo-angiogenesis, inflammation). In this work, copper-substituted bioactive mesoporous glasses (Cu-MBGs) were prepared as nano- and micro-particles and successfully loaded with ibuprofen through an incipient wetness method (loaded ibuprofen approx. 10% w/w). Injectable hybrid formulations were then developed by dispersing ibuprofen-loaded Cu-MBGs within thermosensitive hydrogels based on a custom-made amphiphilic polyurethane. This procedure showed almost no effects on the gelation potential (gelation at 37 °C within 3–5 min). Cu2+ and ibuprofen were co-released over time in a sustained manner with a significantly lower burst release compared to MBG particles alone (burst release reduction approx. 85% and 65% for ibuprofen and Cu2+, respectively). Additionally, released Cu2+ species triggered polyurethane chemical degradation, thus enabling a possible tuning of gel residence time at the pathological site. The overall results suggest that hybrid injectable thermosensitive gels could be successfully designed for the simultaneous localized co-delivery of multiple therapeutics.

scholarly journals Thermosensitive Chitosan Hydrogels Containing Polymeric Microspheres for Vaginal Drug Delivery

2017 ◽  
Vol 2017 ◽  
pp. 1-12 ◽  
Author(s):  
Ting-Ting Yang ◽  
Yuan-Zheng Cheng ◽  
Meng Qin ◽  
Yong-Hong Wang ◽  
Hong-Li Yu ◽  
...  
Keyword(s):  
Drug Delivery ◽  
Sustained Release ◽  
Delivery System ◽  
Drug Loading ◽  
Great Promise ◽  
Burst Release ◽  
Bletilla Striata ◽  
Vaginal Drug Delivery ◽  
Thermosensitive Hydrogels

Thermosensitive hydrogels have increasingly received considerable attention for local drug delivery based on many advantages. However, burst release of drugs is becoming a critical challenge when the hydrogels are employed. Microspheres- (MS-) loaded thermosensitive hydrogels were thus fabricated to address this limitation. Employing an orthogonal design, the spray-dried operations of tenofovir (TFV)/Bletilla striata polysaccharide (BSP)/chitosan (CTS) MS were optimized according to the drug loading (DL). The physicochemical properties of the optimal MS (MS F) were characterized. Depending on the gelation temperature and gelating time, the optimal CTS-sodium alginate- (SA-) α,β-glycerophosphate (GP) (CTS-SA-GP) hydrogel was obtained. Observed by scanning electron microscope (SEM), TFV/BSP/CTS MS were successfully encapsulated in CTS-SA-GP. In vitro releasing demonstrated that MS F-CTS-SA-GP retained desirable in vitro sustained-release characteristics as a vaginal delivery system. Bioadhesion measurement showed that MS-CTS-SA-GP exhibited the highest mucoadhesive strength. Collectively, MS-CTS-SA-GP holds great promise for topical applications as a sustained-release vaginal drug delivery system.

scholarly journals Functional intersection of the kallikrein-related peptidases (KLKs) and thrombostasis axis

2010 ◽  
Vol 391 (4) ◽  
Author(s):  
Michael Blaber ◽  
Hyesook Yoon ◽  
Maria A. Juliano ◽  
Isobel A. Scarisbrick ◽  
Sachiko I. Blaber
Keyword(s):  
Initial Conditions ◽  
Tissue Injury ◽  
Large Body ◽  
Therapeutic Agents ◽  
Specific Interactions ◽  
Complete Understanding ◽  
Functional Interaction ◽  
Regulatory Interactions ◽  
Normal Health ◽  
Over Time

Abstract A large body of emerging evidence indicates a functional interaction between the kallikrein-related peptidases (KLKs) and proteases of the thrombostasis axis. These interactions appear relevant for both normal health as well as pathologies associated with inflammation, tissue injury, and remodeling. Regulatory interactions between the KLKs and thrombostasis proteases could impact several serious human diseases, including neurodegeneration and cancer. The emerging network of specific interactions between these two protease families appears to be complex, and much work remains to elucidate it. Complete understanding how this functional network resolves over time, given specific initial conditions, and how it might be controllably manipulated, will probably contribute to the emergence of novel diagnostics and therapeutic agents for major diseases.

Peak Impact Accelerations during Track and Treadmill Running

2013 ◽  
Vol 29 (5) ◽  
pp. 639-644 ◽  
Author(s):  
Erin M.R. Bigelow ◽  
Niell G. Elvin ◽  
Alex A. Elvin ◽  
Steven P. Arnoczky
Keyword(s):  
Healthy Subjects ◽  
Treadmill Running ◽  
Acrylic Plate ◽  
Custom Made ◽  
The Individual ◽  
Long Term Impact ◽  
Wireless Accelerometer ◽  
Vertical Impact ◽  
Over Time

To determine whether peak vertical and horizontal impact accelerations were different while running on a track or on a treadmill, 12 healthy subjects (average age 32.8 ± 9.8 y), were fitted with a novel, wireless accelerometer capable of recording triaxial acceleration over time. The accelerometer was attached to a custom-made acrylic plate and secured at the level of the L5 vertebra via a tight fitting triathlon belt. Each subject ran 4 miles on a synthetic, indoor track at a self-selected pace and accelerations were recorded on three perpendicular axes. Seven days later, the subjects ran 4 miles on a treadmill set at the individual runner’s average pace on the track and the peak vertical and horizontal impact magnitudes between the track and treadmill were compared. There was no difference (P= .52) in the average peak vertical impact accelerations between the track and treadmill over the 4 mile run. However, peak horizontal impact accelerations were greater (P= .0012) on the track when compared with the treadmill. This study demonstrated the feasibility for long-term impact accelerations monitoring using a novel wireless accelerometer.

scholarly journals Synthesis of the Nakanishi Ring-Locked Retinoid

2011 ◽  
Vol 2011 ◽  
pp. 1-8
Author(s):  
Jamie B. Côté ◽  
Tan D. Quach ◽  
Andrey P. Demenev ◽  
David S. Garvey ◽  
Judd M. Berman
Keyword(s):  
Therapeutic Agents ◽  
Proof Of Concept ◽  
Synthetic Route ◽  
Biological Tool ◽  
Purification Protocol ◽  
Over Time

An optimized synthetic route to prepare ring-locked retinoid 1a has been developed. We fully describe a purification protocol that provides isomerically pure 1a in support of on-going proof of concept studies for the development of therapeutic agents to treat human ADRP. Additionally, we have found that isomerically pure 1a can be stored in amber vials under argon at −20°C for use over time (up to six months) without degradation. Thus, enabling 1a to be an accessible and valuable biological tool.

scholarly journals In vitro Retention Loss of Attachment-retained Removable Partial Denture

2013 ◽  
Vol 14 (6) ◽  
pp. 1049-1053
Author(s):  
Gülsen Can ◽  
Baransel Özmumcu ◽  
Pinar Altinci
Keyword(s):  
Test Machine ◽  
Clinical Use ◽  
Removable Partial Denture ◽  
Partial Denture ◽  
Retention Force ◽  
Retention Loss ◽  
Custom Made ◽  
Slide Type ◽  
Over Time

ABSTRACT Aim To investigate the importance of attachment types on the retention loss of extracoronal attachment-retained removable partial dentures depending on the usage period. Materials and methods In order to observe the retention loss of 5 different attachments (OT Strategy, OT Strategy-metal protected, Vario-stud-snap and Vario-soft 3 and ERA-RV) over time, attachment-retained partial dentures representing Kennedy II mod. I case were placed in a custom-made, retention test machine. For each minute, eight separating and joining movements were performed and retention values (Newton) of the attachments were recorded by computer. The retention tests implemented in 540,1080 and 2160 cycles. The data were evaluated statistically according to the two-way ANOVA and Tukey parametrical tests. Results The slide type attachment providing the best retention force was observed to be the most worn out by this process (p < 0.01) while the ball type attachments, which typically have the lesser retention force, showed less retention loss (p < 0.01). Conclusion It can be concluded that the retention attributes of the attachment-retained dentures were affected by the specific type of precision attachment as well as the usage period. Clinical significance Precision attachments with ball-type plastic matrices may be recommended for the clinical use due to their retention stability over time. How to cite this article Can G, Özmumcu B, Altinci P. In vitro Retention Loss of Attachment-retained Removable Partial Denture. J Contemp Dent Pract 2013;14(6):1049-1053.

Determination of Gelation Kinetic Parameters for a Chitosan/β-Glycerophosphate Injectable Hydrogel by Means of Rheological Measurement

2016 ◽  
Vol 848 ◽  
pp. 543-550 ◽  
Author(s):  
Qian Qian Wang ◽  
Da Jun Chen
Keyword(s):  
Sol Gel ◽  
Gelation Time ◽  
Transition Process ◽  
Reaction Rate Constant ◽  
Disodium Salt ◽  
Injectable Hydrogels ◽  
Rheological Measurement ◽  
Zero Order Kinetics ◽  
Thermosensitive Hydrogels ◽  
Sol Gel Transition

The aim of the current study was to improve the knowledge of the gelation process of injectable thermosensitive hydrogels comprising chitosan (CS) and β-glycerophosphate disodium salt (β-GP). The sol-gel transition process was precisely tracked by means of rheological measurement, in which the viscosity changed considerably with gelation time and temperature. The zero-order kinetics model was assumed to adequately describe the extent of gelation reaction. The reaction rate constant increased continuously with the increasing temperature and β-GP concentration. According to Arrhenius equation, the activation energies of gelation reaction for the chitosan injectable hydrogels were calculated as 64.38 KJ/mol, 101.68 KJ/mol and 140.92 KJ/mol for the samples containing 4% w/v, 6% w/v and 8% w/v of β-GP, respectively. It could be an effective way to study the gelation dynamics of injectable hydrogels, and provide references for clinical practice.

scholarly journals Standardization of an Experimental Murine Model of Invasive Pulmonary Aspergillosis

2006 ◽  
Vol 50 (10) ◽  
pp. 3501-3503 ◽  
Author(s):  
Donald C. Sheppard ◽  
John R. Graybill ◽  
Laura K. Najvar ◽  
Lisa Y. Chiang ◽  
Thomas Doedt ◽  
...  
Keyword(s):  
Murine Model ◽  
Liposomal Amphotericin ◽  
Invasive Pulmonary Aspergillosis ◽  
Therapeutic Agents ◽  
Pulmonary Aspergillosis ◽  
High Level ◽  
Aerosol Infection ◽  
Interlaboratory Reproducibility ◽  
Over Time ◽  
Experimental Murine Model

ABSTRACT Evaluating new therapeutic agents for invasive aspergillosis requires animal models that are reproducible among different laboratories. We therefore evaluated a murine model of aerosol infection in two independent laboratories and found a high level of both intra- and interlaboratory reproducibility of survival, fungal burden over time, and the efficacy of liposomal amphotericin B.

scholarly journals In-Situ Forming pH and Thermosensitive Injectable Hydrogels to Stimulate Angiogenesis: Potential Candidates for Fast Bone Regeneration Applications

2020 ◽  
Vol 21 (5) ◽  
pp. 1633 ◽  
Author(s):  
Fatma Z. Kocak ◽  
Abdullah C.S. Talari ◽  
Muhammad Yar ◽  
Ihtesham U. Rehman
Keyword(s):  
Bone Regeneration ◽  
Sol Gel ◽  
Chorioallantoic Membrane ◽  
Cam Assay ◽  
Injectable Hydrogels ◽  
Angiogenic Potential ◽  
Homogeneous Solutions ◽  
Chick Chorioallantoic Membrane ◽  
Thermosensitive Hydrogels

Biomaterials that promote angiogenesis are required for repair and regeneration of bone. In-situ formed injectable hydrogels functionalised with bioactive agents, facilitating angiogenesis have high demand for bone regeneration. In this study, pH and thermosensitive hydrogels based on chitosan (CS) and hydroxyapatite (HA) composite materials loaded with heparin (Hep) were investigated for their pro-angiogenic potential. Hydrogel formulations with varying Hep concentrations were prepared by sol–gel technique for these homogeneous solutions were neutralised with sodium bicarbonate (NaHCO3) at 4 °C. Solutions (CS/HA/Hep) constituted hydrogels setting at 37 °C which was initiated from surface in 5–10 minutes. Hydrogels were characterised by performing injectability, gelation, rheology, morphology, chemical and biological analyses. Hydrogel solutions facilitated manual dropwise injection from 21 Gauge which is highly used for orthopaedic and dental administrations, and the maximum injection force measured through 19 G needle (17.191 ± 2.296N) was convenient for manual injections. Angiogenesis tests were performed by an ex-ovo chick chorioallantoic membrane (CAM) assay by applying injectable solutions on CAM, which produced in situ hydrogels. Hydrogels induced microvascularity in CAM assay this was confirmed by histology analyses. Hydrogels with lower concentration of Hep showed more efficiency in pro-angiogenic response. Thereof, novel injectable hydrogels inducing angiogenesis (CS/HA/Hep) are potential candidates for bone regeneration and drug delivery applications.

scholarly journals Collaborative Models for Translational Neuroscience and Rehabilitation Research

2009 ◽  
Vol 23 (7) ◽  
pp. 633-640 ◽  
Author(s):  
Bruce H. Dobkin
Keyword(s):  
Neurological Diseases ◽  
Academic Research ◽  
Therapeutic Agents ◽  
Government Agencies ◽  
Translational Neuroscience ◽  
Collaborative Models ◽  
Laboratory Capacity ◽  
Narrow Width ◽  
Ongoing Assessment ◽  
Over Time

Little formal research has been conducted on strategies to structure basic, preclinical, and clinical research to increase the likelihood of discovering efficacious interventions for patients with neurological diseases. How academic research is organized and funded by government agencies and foundations seems likely to affect the quality and rate of production of valued therapeutic agents. Few models for translational biomedical research, however, have been defined and no strategies have been compared. Given the narrow width of expertise and laboratory capacity of individual investigators, the complexity of identifying and manipulating mechanisms of disease components over time, and the demand for solutions from society, our continued reliance on funding therapeutic discovery through standalone investigators and projects seems counterproductive. Models are described for funding collaborations of basic and clinical scientists to work in iterative, adaptable, cross-disciplinary interactions around key progress-limiting questions. Problem-oriented collaborations require leadership, incentives, trust, ongoing assessment, and an efficient infrastructure that overcomes barriers. These models are as testable as the hypotheses that drive scientific research.

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