scholarly journals Ropivacaine-Loaded Poloxamer Binary Hydrogels for Prolonged Regional Anesthesia: Structural Aspects, Biocompatibility, and Pharmacological Evaluation

2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Kelli Cristina Freitas Mariano ◽  
Juliana Zampoli Boava Papini ◽  
Naially Cardoso de Faria ◽  
Daniele Nicoli Cabral Heluany ◽  
Ana Luiza Lourençoni Botega ◽  
...  
Keyword(s):  
Polymer Concentration ◽  
Viscoelastic Behavior ◽  
Histological Evaluation ◽  
Sensory Blockade ◽  
Cytotoxic Effects ◽  
Analgesic Effects ◽  
Viscous Modulus ◽  
Thermosensitive Hydrogels ◽  
Biopharmaceutical Properties

This study reports the development of thermosensitive hydrogels for delivering ropivacaine (RVC), a wide clinically used local anesthetic. For this purpose, poloxamer- (PL-) based hydrogels were synthesized for evaluating the influence of polymer concentration, hydrophilic-lipophilic balances, and binary system formation on biopharmaceutical properties and pharmacological performance. Transition temperatures were shifted, and rheological analysis revealed a viscoelastic behavior with enhanced elastic/viscous modulus relationship ( G ’ / G ” = 1.8 to 22 times), according to hydrogel composition and RVC incorporation. The RVC release from PL407 and PL407/338 systems followed the Higuchi model ( R 2 = 0.923 –0.989), indicating the drug diffusion from hydrogels to the medium. RVC-PL hydrogels were potentially biocompatible evoking low cytotoxic effects (in fibroblasts and Schwann cells) and mild/moderate inflammation signs on sciatic nerve nearby histological evaluation. In vivo pharmacological assays demonstrated that PL407 and PL407/338 evoked differential analgesic effects, by prolonging the sensory blockade duration up to ~340 and 250 min., respectively. All those results highlighted PL407 and PL407/338 as promising new strategies for sustaining analgesic effects during the postoperative period.

scholarly journals Photoprotective activity of geopropolis produced by Melipona subnitida (Apidae, Meliponinae) in the semiarid of the Brazilian Northeast

2021 ◽  
Vol 10 (2) ◽  
pp. e1121021305
Author(s):  
Jael Soares Batista ◽  
Antonio Salatino ◽  
Giuseppina Negri ◽  
Carmen Eusebia P. Jara ◽  
Kaliane Alessandra R. de Paiva ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Histological Evaluation ◽  
Cytotoxic Effects ◽  
Melipona Subnitida ◽  
Varied Chemical ◽  
The Subject ◽  
Brazilian Northeast ◽  
Hydroethanolic Extract

Although geopropolis has been the subject of many chemical and pharmacological studies, there are few studies investigating the photoprotective activity of formulations containing propolis. Thus, we investigated in vivo the photoprotective efficacy of the cream containing geopropolis extract by macroscopic and histological evaluation of the skin of Wistar rats subjected to ultraviolet radiation (UVB). We also evaluated the chemical composition of hydroethanolic extract using the HPLC-DADESI-MS/MS technique, as well as antioxidant activity by the photocolorimetric method of free radical DPPH (2.2-diphenyl-1-picrylhydrazine) and cytotoxic activity by the in vitro MTT quantitative method [brometo de 3- (4.5dimetiltiazol-2-il)-2.5-difeniltetrazolio]. The extract had a varied chemical composition, 29 different phenolic compounds being detected, distributed between phenols and flavonoids, the latter being represented by chalcones, flavones and flavonols. The highest percentages of DPPH inhibition e o baixo valor de IC50 indicaram que o extrato apresentou alta atividade antioxidante. The hydroethanolic extract did not exert cytotoxic effects since high percentages of viability of L929 fibroblasts were observed after incubation for 72 hours at different concentrations of the extract.  On skin submitted to cream application containing of geopropolis extract and the irradiation with UVB did not occur macroscopic and histological lesions. Thus, we concluded that the cream containing of geopropolis extract produced by Melipona subnitida was able to protect the skin from lesions induced by UVB irradiation, thus demonstrating photoprotective effect.

Preparation and Evaluation of Gemifloxacin Mesylate Floating Matrix Tablets in Healthy Human Volunteers

2017 ◽  
Vol 10 (1) ◽  
pp. 3623-3630
Author(s):  
Bhikshapathi D. V. R. N. ◽  
Haarika B ◽  
Jyothi Sri S ◽  
K Abbulu
Keyword(s):  
Drug Release ◽  
Sodium Bicarbonate ◽  
Polymer Concentration ◽  
Hydroxypropyl Methylcellulose ◽  
Matrix Tablets ◽  
Physical Parameters ◽  
Drug Bioavailability ◽  
Floating Tablets

The purpose of present investigation was to develop floating matrix tablets of gemifloxacin mesylate, which after oral administration could prolong the gastric residence time, increase the drug bioavailability and diminish the side effects of irritating drugs. Tablets containing drug, various viscosity grades of hydroxypropyl methylcellulose such as HPMC K4M and HPMC K15M as matrix forming agent, Sodium bicarbonate as gas-forming agent and different additives were tested for their usefulness in formulating gastric floating tablets by direct compression method. The physical parameters, in vitro buoyancy, release characteristics and in vivo radiographic study were investigated in this study. The gemifloxacin mesylate floating tablets were prepared using HPMC K4M polymer giving more sustained drug release than the tablet containing HPMC K15M. All these formulations showed floating lag time of 30 to 47 sec and total floating time more than 12 h. The drug release was decreased when polymer concentration increases and gas generating agent decreases. Formulation that contains maximum concen-tration of both HPMC K15M and sodium bicarbonate (F9) showing sufficiently sustained with 99.2% of drug release at 12 h. The drug release from optimized formulation follows Higuchi model that indicates the diffusion controlled release. The best formulation (F9) was selected based on in vitro characteristics and used in vivo radiographic studies by incorporating barium sulphate as a radio-opaque agent and the tablet remained in the stomach for about 6 h.   

scholarly journals Composite Ferroelectric Membranes Based on Vinylidene Fluoride-Tetrafluoroethylene Copolymer and Polyvinylpyrrolidone for Wound Healing

Membranes ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 21
Author(s):  
Tamara S. Tverdokhlebova ◽  
Ludmila S. Antipina ◽  
Valeriya L. Kudryavtseva ◽  
Ksenia S. Stankevich ◽  
Ilya M. Kolesnik ◽  
...  
Keyword(s):  
Wound Healing ◽  
Vinylidene Fluoride ◽  
Ferroelectric Properties ◽  
Composite Membranes ◽  
Modern Medicine ◽  
In Vivo Studies ◽  
Cytotoxic Effects ◽  
Complex Process ◽  
Purulent Wounds

Wound healing is a complex process and an ongoing challenge for modern medicine. Herein, we present the results of study of structure and properties of ferroelectric composite polymer membranes for wound healing. Membranes were fabricated by electrospinning from a solution of vinylidene fluoride/tetrafluoroethylene copolymer (VDF–TeFE) and polyvinylpyrrolidone (PVP) in dimethylformamide (DMF). The effects of the PVP content on the viscosity and conductivity of the spinning solution, DMF concentration, chemical composition, crystal structure, and conformation of VDF–TeFE macromolecules in the fabricated materials were studied. It was found that as PVP amount increased, the viscosity and conductivity of the spinning solutions decreased, resulting in thinner fibers. Using FTIR and XRD methods, it was shown that if the PVP content was lower than 50 wt %, the VDF–TeFE copolymer adopted a flat zigzag conformation (TTT conformation) and crystalline phases with ferroelectric properties were formed. Gas chromatography results indicated that an increase in the PVP concentration led to a higher residual amount of DMF in the material, causing cytotoxic effects on 3T3L1 fibroblasts. In vivo studies demonstrated that compared to classical gauze dressings impregnated with a solution of an antibacterial agent, ferroelectric composite membranes with 15 wt % PVP provided better conditions for the healing of purulent wounds.

scholarly journals Antidiabetic and antiulcerative potential of Garcinia lanceifolia Roxb. bark

2020 ◽  
Vol 6 (1) ◽  
Author(s):  
Nilutpal Sharma Bora ◽  
Partha Sarathi Bairy ◽  
Abdus Salam ◽  
Bibhuti Bhusan Kakoti
Keyword(s):  
Body Weight ◽  
Serum Levels ◽  
Northeast India ◽  
Scientific Data ◽  
Antidiabetic Activity ◽  
Histological Evaluation ◽  
Albino Rats ◽  
Antiulcer Activity ◽  
Dose Dependent

Abstract Background Garcinia lanceifolia Roxb. has been used by many ethnic communities of Northeast India to mitigate various disorders like dyspepsia, ulcers, diabetes, etc. However, a robust scientific study on its antidiabetic and antiulcer potential is unavailable till date. The aim of this present study is to scientifically validate if the antidiabetic and antiulcer effects reported by the ethnic tribes of Assam has any scientific value or not. The effects were tested in adult Wistar albino rats using approved animal models for preclinical testing of pharmacological activities. Results The hydroalcoholic extract of the bark of Garcinia lanceifolia Roxb. was prepared and its LD50 was calculated. The LD50 was determined to be greater than 5000 mg/kg body weight. The extract at doses of 250 mg/kg body weight and 500 mg/kg body weight was found to exhibit a very potent dose-dependent antidiabetic activity. The results were backed by a battery of test including analysis of serum levels of blood glucose, lipid profiles, in vivo antioxidant enzymes, and histopathological studies. Evidence of dose-dependent antiulcer activity of the extract was backed by robust scientific data. It was found that HAEGL induced a significant dose-dependent increase in the ulcer index in both alcohol-induced and acetic acid-induced ulcer models, which was evident from the macroscopic observation of the inner lining of the gastric mucosa and the histological evaluation of the extracted stomach. Conclusion The results suggested that the bark of Garcinia lanceifolia (Roxb.) has significant antidiabetic and antiulcer potential. Further studies with respect to the development herbal dosage forms and its safety evaluation are required.

scholarly journals Silver Nanoparticles and Their Antibacterial Applications

2021 ◽  
Vol 22 (13) ◽  
pp. 7202
Author(s):  
Tamara Bruna ◽  
Francisca Maldonado-Bravo ◽  
Paul Jara ◽  
Nelson Caro
Keyword(s):  
Silver Nanoparticles ◽  
Antibacterial Agents ◽  
Multidrug Resistant ◽  
Secondary Effects ◽  
Cytotoxic Effects ◽  
Factors Affecting ◽  
Gram Positive Bacteria ◽  
Resistant Strains

Silver nanoparticles (AgNPs) have been imposed as an excellent antimicrobial agent being able to combat bacteria in vitro and in vivo causing infections. The antibacterial capacity of AgNPs covers Gram-negative and Gram-positive bacteria, including multidrug resistant strains. AgNPs exhibit multiple and simultaneous mechanisms of action and in combination with antibacterial agents as organic compounds or antibiotics it has shown synergistic effect against pathogens bacteria such as Escherichia coli and Staphylococcus aureus. The characteristics of silver nanoparticles make them suitable for their application in medical and healthcare products where they may treat infections or prevent them efficiently. With the urgent need for new efficient antibacterial agents, this review aims to establish factors affecting antibacterial and cytotoxic effects of silver nanoparticles, as well as to expose the advantages of using AgNPs as new antibacterial agents in combination with antibiotic, which will reduce the dosage needed and prevent secondary effects associated to both.

The Toxic Effects of Two Dental Materials on Human Buccal Epithelium In Vitro and Monkey Buccal Epithelium In Vivo

1987 ◽  
Vol 14 (3) ◽  
pp. 166-167
Author(s):  
D. Arenholt-Bindslev ◽  
P. Hørsted-Bindslev ◽  
H.P. Philipsen
Keyword(s):  
Dental Materials ◽  
Microscopical Examination ◽  
Buccal Epithelium ◽  
Cytotoxic Effects ◽  
Buccal Epithelial Cells ◽  
Toxicity In Vitro ◽  
Toxic Reactions ◽  
Light Microscopical Examination

The aim of the present study was to compare the toxicity in vitro with the toxicity in vivo of two commercial chemicals marketed for use in the oral cavity (GLUMA BondR and 3M Etching LiquidR). Confluent cultures of human buccal epithelial cells were exposed to graded concentrations of GLUMA Bond or 3M Etching Liquid for 5 minutes. The cytotoxic effects induced by this treatment were observed (cytomorphology, proliferation rate). In vivo, monkey buccal epithelium was exposed to GLUMA Bond or 3M Etching Liquid for 5 minutes. Biopsies were taken after 24 hours, and the buccal epithelium processed for light microscopical examination. In both models, the toxic reactions to GLUMA Bond were far more extensive than those caused by 3M Etching Liquid.

scholarly journals Satureja subspicata and S. horvatii Extracts Induce Overexpression of the BCl-2 Family of Anti-apoptotic Genes and Reduce Micronuclei Frequency in Mice

2018 ◽  
Vol 13 (6) ◽  
pp. 1934578X1801300
Author(s):  
Jasmina Čakar ◽  
Naida Kadrić Lojo ◽  
Anja Haverić ◽  
Maida Hadžić ◽  
Lejla Lasić ◽  
...  
Keyword(s):  
Human Lymphocyte ◽  
Micronucleus Assay ◽  
Balkan Peninsula ◽  
Lymphocyte Culture ◽  
Cytotoxic Activities ◽  
Cytotoxic Effects ◽  
Apoptotic Genes ◽  
Apoptotic Activity

Satureja subspicata and S. horvatii are endemic species of the Balkan Peninsula and often used in traditional medicine in Bosnia and Herzegovina to treat different health conditions. We aimed to analyze the unevaluated apoptotic, genotoxic and cytotoxic effects of two Satureja species, as well as their content of phenolics that are mainly responsible for the plant's biological activity. Apoptotic and geno/cytotoxic activities of S. subspicata and S. horvatii were investigated in vitro in human lymphocyte culture and in vivo in mice. The content of the main phenolics in plant extracts was determined by ultra-high pressure liquid chromatography-MS-MS (UHPLC–MS/MS). Genotoxic and cytotoxic activities of Satureja extracts were evaluated in vitro by applying a cytokinesis-block micronucleus cytome assay in human lymphocyte culture and in vivo applying a mice reticulocytes micronucleus assay. SALSA RT-MLPA R011-C1 apoptosis assay was used for measuring the relative expression of 44 genes associated with the regulation of the apoptotic pathways in human lymphocyte cultures treated with different concentrations of two Satureja extracts. The first analysis of phenolic compounds in S. horvatii and S. subspicata determined by an UHPLC-MS/MS method revealed high levels of rosmarinic and caffeic acids. Minor genotoxic potential was determined in relation to the tested concentrations while no cytostatic and cytotoxic effects were revealed in vitro. However, when applied in concentrations of 200 mg/kg per os, aqueous extracts of two Satureja species significantly decreased frequency of reticulocytes micronuclei in treated mice against controls. Extracts of S. subspicata and S. horvatii in concentrations of 0.2 mg/mL, regardless of solvent used, downregulated pro-apoptotic and upregulated anti-apoptotic genes, showing anti-apoptotic activity. Our results indicate that the registered anti-genotoxic and anti-apoptotic activity is most likely related to the high level of phenolic acids (particularly rosmarinic and caffeic) in the tested extracts.

scholarly journals EXTH-70. ENHANCEMENT OF ANTITUMOR ACTIVITY BY USING 5-ALA–MEDIATED SONODYNAMIC THERAPY TO INDUCE APOPTOSIS AND NECROSIS IN A MOUSE GLIOMA MODEL

2019 ◽  
Vol 21 (Supplement_6) ◽  
pp. vi97-vi97
Author(s):  
Satoshi Suehiro ◽  
Takanori Ohnishi ◽  
Akihiro Inoue ◽  
Daisuke Yamashita ◽  
Masahiro Nishikawa ◽  
...  
Keyword(s):  
Tumor Cells ◽  
Malignant Gliomas ◽  
Glioma Cells ◽  
High Intensity Focused Ultrasound ◽  
Control Group ◽  
Normal Brain ◽  
Sonodynamic Therapy ◽  
Cytotoxic Effects

Abstract OBJECTIVE High invasiveness of malignant gliomas frequently causes local tumor recurrence. To control such recurrence, novel therapies targeted toward infiltrating glioma cells are required. Here, we examined cytotoxic effects of sonodynamic therapy (SDT) combined with a sonosensitizer, 5-aminolevulinic acid (5-ALA), on malignant gliomas both in vitro and in vivo. METHODS In vitro cytotoxicity of 5-ALA-SDT was evaluated in U87 and U251 glioma cells and in U251Oct-3/4 glioma stemlike cells. Treatment-related apoptosis was analyzed using flow cytometry. Intracellular reactive oxygen species (ROS) were measured and the role of ROS in treatment-related cytotoxicity was examined. Effects of 5-ALA-SDT with high-intensity focused ultrasound (HIFU) on tumor growth, survival of glioma-transplanted mice, and histological features of the mouse brains were investigated. RESULTS The 5-ALA-SDT inhibited cell growth and changed cell morphology. Flow cytometric analysis indicated that 5-ALA-SDT induced apoptotic cell death. The 5-ALA-SDT generated higher ROS than in the control group, and inhibition of ROS generation completely eliminated the cytotoxic effects of 5-ALA-SDT. In the in vivo study, 5-ALA-SDT with HIFU greatly prolonged survival of the tumor-bearing mice compared with that of the control group (p < 0.05). Histologically, 5-ALA-SDT produced mainly necrosis of the tumor tissue in the focus area and induced apoptosis of the tumor cells in the perifocus area around the target of the HIFU-irradiated field. Normal brain tissues around the ultrasonic irradiation field of HIFU remained intact. CONCLUSIONS The 5-ALA-SDT was cytotoxic toward malignant gliomas. Generation of ROS by the SDT was thought to promote apoptosis of glioma cells. The 5-ALA-SDT with HIFU induced tumor necrosis in the focus area and apoptosis in the perifocus area of the HIFU-irradiated field. These results suggest that 5-ALA-SDT with HIFU may present a less invasive and tumor-specific therapy, not only for a tumor mass but also for infiltrating tumor cells in malignant gliomas.

scholarly journals Longitudinal in vivo evaluation of bone regeneration by combined measurement of multi-pinhole SPECT and micro-CT for tissue engineering

2015 ◽  
Vol 5 (1) ◽  
Author(s):  
Philipp S. Lienemann ◽  
Stéphanie Metzger ◽  
Anna-Sofia Kiveliö ◽  
Alain Blanc ◽  
Panagiota Papageorgiou ◽  
...  
Keyword(s):  
Computed Tomography ◽  
High Resolution ◽  
Bone Formation ◽  
Bone Regeneration ◽  
Bone Defects ◽  
Histological Evaluation ◽  
Biological Processes ◽  
Micro Ct ◽  
Pinhole Spect

Abstract Over the last decades, great strides were made in the development of novel implants for the treatment of bone defects. The increasing versatility and complexity of these implant designs request for concurrent advances in means to assess in vivo the course of induced bone formation in preclinical models. Since its discovery, micro-computed tomography (micro-CT) has excelled as powerful high-resolution technique for non-invasive assessment of newly formed bone tissue. However, micro-CT fails to provide spatiotemporal information on biological processes ongoing during bone regeneration. Conversely, due to the versatile applicability and cost-effectiveness, single photon emission computed tomography (SPECT) would be an ideal technique for assessing such biological processes with high sensitivity and for nuclear imaging comparably high resolution (<1 mm). Herein, we employ modular designed poly(ethylene glycol)-based hydrogels that release bone morphogenetic protein to guide the healing of critical sized calvarial bone defects. By combined in vivo longitudinal multi-pinhole SPECT and micro-CT evaluations we determine the spatiotemporal course of bone formation and remodeling within this synthetic hydrogel implant. End point evaluations by high resolution micro-CT and histological evaluation confirm the value of this approach to follow and optimize bone-inducing biomaterials.

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