scholarly journals Effect of the CCL5-Releasing Fibrin Gel for Intervertebral Disc Regeneration

Cartilage ◽  
2018 ◽  
Vol 11 (2) ◽  
pp. 169-180 ◽  
Author(s):  
Zhiyu Zhou ◽  
Stephan Zeiter ◽  
Tanja Schmid ◽  
Daisuke Sakai ◽  
James C. Iatridis ◽  
...  
Keyword(s):  
Animal Study ◽  
Culture Media ◽  
Histopathological Examination ◽  
In Vitro Release ◽  
Dependent Manner ◽  
Fibrin Gel ◽  
Defect Sites ◽  
Intervertebral Disc Regeneration ◽  
Chemotactic Effect

Objective To explore if chemokine (C-C motif) ligand 5 (CCL5) delivery could recruit annulus fibrosus (AF) cells to the injury sites and facilitate the repair of ruptured AF. Design The effects of CCL5 on bovine AF cells in vitro were tested by transwell assay and quantitative real-time polymerase chain reaction. Fibrin gel containing CCL5 was used to treat annulotomized bovine caudal discs cultured under dynamic loading conditions. After 14 days of loading, the samples were collected for histological examination. A pilot animal study was performed using sheep cervical discs to investigate the effect of fibrin gel encapsulated with CCL5 for the treatment of ruptured AF. After 14 weeks, the animals were sacrificed, and the discs were scanned with magnetic resonance imaging before histopathological examination. Results CCL5 showed a chemotactic effect on AF cells in a dose-dependent manner. AF cells cultured with CCL5 in vitro did not show any change of the gene expression of CCL5 receptors, catabolic and proinflammatory markers. In vitro release study showed that CCL5 exhibited sustained release from the fibrin gel into the culture media; however, in the organ culture study CCL5 did not stimulate homing of AF cells toward the defect sites. The pilot animal study did not show any repair effect of CCL5. Conclusions CCL5 has a chemotactic effect on AF cells in vitro, but no ex vivo or in vivo regenerative effect when delivered within fibrin gel. Further study with a stronger chemotactic agent and/or an alternate biomaterial that is more conductive of cell migration is warranted.

scholarly journals The effect of calcium antagonists on the growth of Entamoeba histolytica in vitro

2010 ◽  
Vol 4 (1) ◽  
pp. 5-10
Author(s):  
Zahra’a Abdul-Raheem Ahmed ◽  
Ali H. Ad’hiah ◽  
Amna N. Jasim
Keyword(s):  
Entamoeba Histolytica ◽  
Calcium Antagonists ◽  
Culture Media ◽  
Agar Medium ◽  
Reproduction Rate ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Infusion Agar ◽  
Ethylene Diaminetetraacetic Acid

he E. histolytica parasite was maintained in vitro using Locke-egg medium (LEM) and Liver infusion agar medium (LIAM). The effect of two calcium antagonists (Nifedipine and Ethylene-diaminetetraacetic acid EDTA) on the growth and activity of the parasite in the two culture media was investigated. The calcium antagonists Nifedipine and EDTA inhibited the reproduction rate of E. histolytica in a concentration-dependent manner. For Nifedipine, a concentration of 41.6 mg/ml inhibited the reproduction rate to 99.7% in both media. The EDTA had an approximate effect (98.2 and 95.8)% at a concentration of 0.83 mg/ml in LEM and LIAM media, respectively. Additionally, some cases of a parasite encystment were observed in LEM medium that was treated with Nifedipine.

Antral gland cell column: a method for studying release of gastric hormones

1983 ◽  
Vol 245 (4) ◽  
pp. G463-G469
Author(s):  
B. Richelsen ◽  
J. F. Rehfeld ◽  
L. I. Larsson
Keyword(s):  
In Vitro Release ◽  
Dependent Manner ◽  
Gastrin Release ◽  
Cell Column ◽  
Independent Manner ◽  
Response Characteristics ◽  
Dose Dependent ◽  
Vitro Release ◽  
Stimulation Of

A technique for studying in vitro release of gastric hormones has been developed. The system utilizes nonenzymatically isolated antropyloric glands from humans or rats, which are perifused in a Bio-Gel P-2 column. The system permits the study of kinetics and dose-response characteristics using the glands as their own control. The glands were stimulated with carbachol and bombesin, and the antral peptides gastrin and somatostatin were measured. Bombesin and carbachol both evoked a dose-dependent stimulation of gastrin release, beginning at below 10(-10) M (bombesin) and 10(-7) M (carbachol). Carbachol inhibited the release of somatostatin in a dose-dependent manner, being maximally effective at 10(-6) M and then producing 60% inhibition of somatostatin release. Bombesin was without effect on antropyloric somatostatin release. These data suggest that the gastrin-stimulating effect of carbachol is partially or totally due to inhibition of somatostatin release, whereas bombesinergic stimulation of gastrin release must work in an independent manner. In addition, data on the effects of these substances on the release of gastrin and ACTH-like peptides from human antropyloric glands are presented. Due to the absence of local neural reflexes, this system is a useful supplement to the isolated perfused stomach model.

A Novel Liposomal Bupivacaine Formulation to Produce Ultralong-Acting Analgesia

2004 ◽  
Vol 101 (1) ◽  
pp. 133-137 ◽  
Author(s):  
Gilbert J. Grant ◽  
Yechezkel Barenholz ◽  
Elijah M. Bolotin ◽  
Mylarrao Bansinath ◽  
Herman Turndorf ◽  
...  
Keyword(s):  
Ammonium Sulfate ◽  
In Vitro Release ◽  
Rank Test ◽  
Dependent Manner ◽  
Liposomal Bupivacaine ◽  
Freeze And Thaw ◽  
Phospholipid Ratio ◽  
Remote Loading ◽  
Vitro Release

Background Currently available local anesthetics have relatively brief durations of action. An ultralong-acting local anesthetic would benefit patients with acute and chronic pain. The authors prepared and characterized a novel liposomal bupivacaine formulation using remote loading of bupivacaine along an ammonium sulfate gradient and assessed its efficacy in humans. Methods A large multivesicular liposomal bupivacaine formulation was prepared by subjecting small unilamellar vesicles to successive freeze-and-thaw cycles. Bupivacaine hydrochloride was then remotely loaded into the liposomes along an ammonium sulfate gradient ([(NH4)2SO4)]intraliposome/[(NH4)2SO4)]medium > 1000). The liposomes were then characterized for size distribution; drug-to-phospholipid ratio; in vitro release profile at 4 degree, 21 degree C, and 37 degree C; sterility; and pyrogenicity. Six subjects each received six intradermal injections in the lower back with 0.5 ml of 0.5, 1.0, and 2% liposomal bupivacaine; 0.5% standard bupivacaine; saline; and "empty" liposomes. Duration of analgesia was assessed using pinprick testing of the skin directly over the injection sites. Results were compared using the log-rank test. Results The mean large multivesicular vesicle size was 2439 +/- 544 nm, with a drug-to-phospholipid ratio of 1.8, fivefold greater than results previously reported. In vitro release was slowest at 4 degree C. The median duration of analgesia with 0.5% standard bupivacaine was 1 h. The median durations of analgesia after 0.5, 1.0, and 2.0% liposomal bupivacaine were 19, 38, and 48 h, respectively. Neither saline nor "empty" liposomes produced analgesia. Conclusions This novel liposomal formulation had a favorable drug-to-phospholipid ratio and prolonged the duration of bupivacaine analgesia in a dose-dependent manner. If these results in healthy volunteers can be duplicated in the clinical setting, this formulation has the potential to significantly impact the management of pain.

Repurposing Glyburide as Antileishmanial Agent to Fight Against Leishmaniasis

2019 ◽  
Vol 26 (5) ◽  
pp. 371-376 ◽  
Author(s):  
Abdur Rub ◽  
Kamal Shaker ◽  
Mohammad Kashif ◽  
Mohd Arish ◽  
Abdul Aziz Bin Dukhyil ◽  
...  
Keyword(s):  
Leishmania Donovani ◽  
Culture Media ◽  
Drug Repurposing ◽  
Parasite Growth ◽  
High Rate ◽  
Mammalian Host ◽  
Dependent Manner ◽  
The World

Background: Leishmaniasis is caused by a protozoan parasite, Leishmania. It is common in more than 98 countries throughout the world. Due to insufficient availability of antileishmanial chemotherapeutics, it is an urgent need to search for new molecules which have better efficacy, low toxicity and are available at low cost. Objectives: There is a high rate of diabetic cases throughout the world that is why we planned to test the antileishmanial activity of glyburide, an effective sugar lowering drug used for the treatment of diabetes. In this study, glyburide showed a significant decrease in the parasite growth and survival in vitro in a dose-dependent manner. Methods: Anti-leishmanial activity of glyburide was checked by culturing Leishmania donovani promastigotes in the presence of glyburide in a dose and time dependent manner. Docking study against Leishmania donovani-Trypanothione synthetase (LdTrySyn) protein was performed using Autodock Vina tool. Results: Growth reversibility assay shows that growth of treated parasite was not reversed when transferred to fresh culture media after 7 days. Moreover, docking studies show efficient interactions of glyburide with key residues in the catalytic site of Leishmania donovani- Trypanothione synthetase (LdTrySyn), a very important leishmanial enzyme involved in parasite’s survival by detoxification of Nitric Oxide (NO) species, generated by the mammalian host as a defense molecule. Thus this study proves that the drug-repurposing is a beneficial strategy for identification of new and potent antileishmanial molecules. Conclusion: The results suggest that glyburide binds to LdTrySyn and inhibits its activity which further leads to the altered parasite morphology and inhibition of parasite growth. Glyburide may also be used in combination with other anti-leishmanial drugs to potentiate the response of the chemotherapy. Overall this study provides information about combination therapy as well as a single drug treatment for the infected patients suffering from diabetes. This study also provides raw information for further in vivo disease model studies to confirm the hypothesis.

Fibronectin provides a conduit for fibroblast transmigration from collagenous stroma into fibrin clot provisional matrix

1997 ◽  
Vol 110 (7) ◽  
pp. 861-870 ◽  
Author(s):  
D. Greiling ◽  
R.A. Clark
Keyword(s):  
Wound Healing ◽  
In Vitro Model ◽  
Collagen Gel ◽  
Fibrin Clot ◽  
Dependent Manner ◽  
Fibrin Gel ◽  
Concentration Dependent Manner ◽  
Vitro Model ◽  
Early Wound

After injury, the wound space is filled with a fibrin/fibronectin clot containing growth factors released by platelets and monocytes. In response to these factors, fibroblasts migrate into the fibrin clot and contribute to the formation of granulation tissue. The functional mechanisms allowing fibroblasts to leave the collagenous matrix of normal connective tissue and invade the provisional matrix of the fibrin clot have not been fully defined. To investigate these mechanisms we established a new in vitro model which simulates specific aspects of early wound healing, that is, the migration of fibroblasts from a three-dimensional collagen matrix into a fibrin clot. This transmigration could be induced by physiological concentrations of platelet releasate or platelet-derived growth factor BB (PDGF-BB) in a concentration-dependent manner. At 24 hours irradiated fibroblasts invaded the fibrin gel almost as well as non-irradiated cells, indicating that transmigration was independent of proliferation. Plasminogen and its activators appear to be necessary for invasion of the fibrin clot since protease inhibitors decreased the amount of migration. These serine proteases, however, were not necessary for exit from the collagen gel as fibroblasts migrated out of the collagen gel onto a surface coated with fibrin fibrils even in the presence of inhibitors. Removal of fibronectin (FN) from either the collagen gel or the fibrin gel markedly decreased the number of migrating cells, suggesting that FN provides a conduit for transmigration. Cell movement in the in vitro model was inhibited by RGD peptide, and by monoclonal antibodies against the subunits of the alpha5 beta1 and alpha v beta3 integrin receptor. Thus, the functional requirements for fibroblast transmigration from collagen-rich to fibrin-rich matrices, such as occurs in early wound healing, have been partially defined using an in vitro paradigm of this important biologic process.

scholarly journals Sequential Delivery of Dual Growth Factors from Injectable Chitosan-Based Composite Hydrogels

Marine Drugs ◽  
2019 ◽  
Vol 17 (6) ◽  
pp. 365 ◽  
Author(s):  
Qing Min ◽  
Jiaoyan Liu ◽  
Xiaofeng Yu ◽  
Yuchen Zhang ◽  
Jiliang Wu ◽  
...  
Keyword(s):  
Bone Repair ◽  
In Vitro Release ◽  
C2c12 Cells ◽  
Bone Morphogenetic Protein 2 ◽  
Temporal Separation ◽  
Composite Gels ◽  
Sequential Release ◽  
Morphogenetic Protein ◽  
Chemotactic Effect

Local administration of platelet-derived growth factor-BB (PGDF-BB) and bone morphogenetic protein-2 (BMP-2) in a sequential release manner could substantially promote bone healing. To achieve this goal, a delivery system that could sustain the release of PGDF-BB and BMP-2 by way of temporal separation was developed. One type of PGDF-BB-encapsulated alginate microsphere and another type of BMP-2-encapsulated microsphere with a core-shell structure were respectively produced using emulsification methods. These two types of microspheres were then embedded into chitosan/glycerophosphate hydrogel for constructing composite gels. Some of them were found to be injectable at ambient temperature and had thermo-sensitive features near physiological temperature and pH. The optimally formulated composite gels showed the ability to control the release of PGDF-BB and BMP-2 in a sequential fashion in which PDGF-BB was released earlier than BMP-2. In vitro release patterns indicated that the release rates could be significantly regulated by varying the embedded amount of the factor-encapsulated microspheres, which can in turn mediate the temporal separation release interval between PGDF-BB and BMP-2. The released PDGF-BB and BMP-2 were detected to be bioactive based on their respective effects on Balb/c 3T3 and C2C12 cells. These results suggest that the presently developed composite gels have the potential for bone repair by synergistically utilizing the early chemotactic effect of PDGF-BB and the subsequent osteogenic and angiogenic functions of PDGF-BB and BMP-2.

scholarly journals Effect of bacterial endotoxin on the in vitro release of Type II phospholipase-A2 and prostaglandin E2 from human placenta

1999 ◽  
Vol 160 (2) ◽  
pp. 291-296 ◽  
Author(s):  
W Farrugia ◽  
L Nicholls ◽  
GE Rice
Keyword(s):  
Prostaglandin E2 ◽  
Phospholipase A2 ◽  
Incubation Medium ◽  
In Vitro Release ◽  
Bacterial Endotoxin ◽  
Dependent Manner ◽  
Type Ii ◽  
Intracellular Enzyme ◽  
Tissue Content

The aim of this study was to establish the effect of bacterial endotoxin lipopolysaccharide (LPS) on the release of Type II phospholipase-A2 (PLA2) and prostaglandin E2 (PGE2) from late-pregnant human placental tissue incubated in vitro. Under basal conditions, immunoreactive Type II PLA2 and PGE2 were released from tissue explants in a time-dependent manner (up to 24 h, ANOVA, P<0. 0001, n=6). The release of these mediators was not associated with a loss of cell membrane integrity, as indicated by concentrations of the intracellular enzyme, lactate dehydrogenase (LDH), in the incubation medium. Incubation of explants in the presence of LPS (0. 001-100 microg LPS/ml) significantly decreased PLA2 tissue content (P<0.02, n=6) and increased the accumulation of PLA2 and PGE2 in the incubation medium (P<0.0001, n=6). The data obtained in this study indicated that Type II PLA2 and PGE2 are released from term placenta under basal conditions and that LPS stimulated their release. The associated decrease in PLA2 tissue content is consistent with the hypothesis that LPS induces the release of stored PLA2. This study identifies one pathway by which products of bacterial infection may induce the release of a pro-inflammatory, extracellularly active PLA2 from intrauterine tissues that may promote the formation of phospholipid metabolites involved in the process of labour and delivery (e.g. the prostaglandins).

scholarly journals Expression of a Mycobacterium tuberculosis Arabinomannan Antigen In Vitro and In Vivo

2001 ◽  
Vol 69 (9) ◽  
pp. 5671-5678 ◽  
Author(s):  
J. Reid Schwebach ◽  
Arturo Casadevall ◽  
Rachel Schneerson ◽  
Zhongdong Dai ◽  
Xiaojuan Wang ◽  
...  
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Culture Media ◽  
Extended Period ◽  
Tween 80 ◽  
Surface Expression ◽  
Dependent Manner ◽  
Bacteria Growth ◽  
Growth Changes

ABSTRACT The outermost layer of Mycobacterium tuberculosiscontains two major polysaccharides, arabinomannan (AM) and glucan (GC). We studied the in vitro and in vivo expression of anM. tuberculosis AM antigen using monoclonal antibody (MAb) 9d8 (2a), an isotype-switched variant of the immunoglobulin G3 (IgG3) MAb 9d8. MAb 9d8 had been previously shown to bind M. tuberculosis AM and the M. tuberculosis surface. Our in vitro experiments showed that MAb 9d8(2a) bound strongly to whole-cell M. tuberculosis Erdman but not to the CDC 1551 strain grown in medium for an extended period. However, AM antigen was detected in the culture supernatant of both strains, and its concentration increased in a time-dependent manner. The detection of AM antigen from both strains was decreased in the presence of Tween 80. In mice infected with M. tuberculosis Erdman, AM antigen accumulated in organ homogenates concomitant to an increase in bacterial organ burden and an increase in IgG and IgM titer to AM. These results (i) indicate that the surface expression of AM during in vitro growth changes with culture age, is strain dependent, and is affected by the presence of Tween 80 in the culture media; (ii) show that AM is produced by bacteria growth in vivo; and (iii) demonstrate that the amount of in vivo-detected AM can be dependent on the number of bacteria in the infected organ.

Formulation and Evaluation of Teneligliptine Pellet

2019 ◽  
Vol 9 (01) ◽  
pp. 51-57
Author(s):  
Bodhle Priyanka Raju ◽  
Satish V Shirolkar
Keyword(s):  
Chemical Interaction ◽  
In Vitro Release ◽  
Angle Of Repose ◽  
Dependent Manner ◽  
32 Factorial Design ◽  
Formulation Parameters ◽  
Tapped Density ◽  
Vitro Release ◽  
Pellet Formulation

The present study is an attempt to formulate and evaluate Teneligliptin hydrobromide hydrate pellets. Teneligliptin is a potent, selective DPP-4 inhibitor, which is believed to exert its actions in diabetes mellitus patients. Teneligliptin increases insulin release and decreases glucagon levels in the circulation in a glucose dependent manner. The Teneligliptin pellets were prepared by using blend of MCC, Lactose, Crospovidone and PVP K-30. Pellet formulation was optimized for formulation parameters (concentration of Crosspovidone and PVP K-30) using 32 factorial design. FTIR studies showed absence of chemical interaction between the drug and polymer. The pellets were prepared and evaluated in terms of bulk density, tapped density, angle of repose and in-vitro release study. In-vitro release of drug was compared with in-vitro release of drug from marketed formulation (Dynaglipt Tablet).

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