scholarly journals Quantitative Characterization of the Hemorrhagic, Necrotic, Coagulation-Altering Properties and Edema-Forming Effects of Zebra Snake (Naja nigricincta nigricincta) Venom

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Erick Kandiwa ◽  
Borden Mushonga ◽  
Alaster Samkange ◽  
Ezequiel Fabiano
Keyword(s):  
Broiler Chicks ◽  
Thrombolytic Activity ◽  
Linear Dose ◽  
Paw Oedema ◽  
Freeze Dried ◽  
Phosphate Buffered Saline ◽  
Dose Dependent ◽  
Subplantar Injection

This study was designed to investigate the cytotoxicity and haemotoxicity of the Western barred (zebra) spitting cobra (Naja nigricincta nigricincta) venom to help explain atypical and inconsistent reports on syndromes by Namibian physicians treating victims of human ophidian accidents. Freeze-dried venom milked from adult zebra snakes was dissolved in phosphate buffered saline (PBS) for use in this study. Haemorrhagic and necrotic activity of venom were studied in New Zealand albino rabbits. Oedema-forming activity was investigated in 10-day-old Cobb500 broiler chicks. Procoagulant and thrombolytic activity was investigated in adult Kalahari red goat blood in vitro. The rabbit skin minimum hemorrhagic dose (MHD) for N. n. nigricincta was 9.8μg. The minimum necrotizing dose (MND) for N. n. nigricincta venom was 12.2μg. The N. n. nigricincta venom showed linear dose-dependent procoagulant activity on goat blood (p<0.05). Likewise, N. n. nigricincta venom showed linear dose-dependent thrombolytic activity on goat blood (p<0.05, n = 6). Subplantar injection of N. n. nigricincta venom (25μg, 50μg, 75μg, and 100μg) into chick paw resulted in peak oedema of 35.5%, 38.5%, 42.9%, and 47.5%, respectively, two hours after injection. Paw oedema subsided within five hours to a mean volume ranging from 5% (25μg venom) to 17.6% (100μg venom). In conclusion, though N. n. nigricincta belongs to the genus Elapidae, the current study has shown its venom to possess potent hemorrhagic, necrotic (cytotoxic), and paradoxically, both procoagulant and thrombolytic activity. The authors propose further work to fractionate, isolate, and elucidate the structure of the various N. n. nigricincta venom toxins as a prelude to the development of an antivenom.

Production and utilization of monoclonal antibodies to human/rat corticotrophin-releasing factor-41

1990 ◽  
Vol 5 (2) ◽  
pp. 159-166 ◽  
Author(s):  
N. G. N. Milton ◽  
E. W. Hillhouse ◽  
S. A. Nicholson ◽  
C. H. Self ◽  
A. M. McGregor
Keyword(s):  
Monoclonal Antibodies ◽  
Enzyme Linked Immunosorbent Assay ◽  
Dependent Manner ◽  
Corticotrophin Releasing Factor ◽  
Tissue Extracts ◽  
Rat Pituitary ◽  
Hypothalamic Tissue ◽  
Dose Dependent

ABSTRACT Murine monoclonal antibodies against human/rat corticotrophin-releasing factor-41 (CRF-41) were produced and characterized for use in the immunological and biological characterization of CRF-41. Spleen cells from BALB/c mice immunized with CRF-41 conjugated to bovine γ-globulin were fused with a BALB/c-derived non-secretor X-63 myeloma line. Hybridomas were selected for CRF antibody production by enzyme-linked immunosorbent assay, and positive hybridomas cloned twice. Three monoclonal antibodies were obtained (KCHMB001, KCHMB002 and KCHMB003) and characterized as IgG1, IgG1 and IgG2a isotypes respectively, with affinity constants for rat CRF-41 of 30, 53 and 34 nmol/l respectively. All three monoclonal antibodies recognize an epitope contained between residues 34 and 41 of the human/rat sequence. The antibodies were able to neutralize the ACTH-releasing activity of rat CRF-41, applied to rat pituitary fragments in vitro, in a dose-dependent manner. Isoelectric focusing showed that KCHMB 003 detected bands of synthetic rat CRF-41 and rat [Met(O)21,38]-CRF-41 at pH 7·1 and 6·8 respectively. Use of KCHMB003 in a two-site enzyme-amplified immunoassay showed that this antibody recognizes both synthetic rat CRF-41 and immunoreactive CRF-41 in rat hypothalamic tissue extracts.

scholarly journals Anti-Inflammatory Activity of Pleurotus ostreatus, a Culinary Medicinal Mushroom, in Wistar Rats

2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
W. J. A. Banukie N. Jayasuriya ◽  
Shiroma M. Handunnetti ◽  
Chandanie A. Wanigatunge ◽  
Gita H. Fernando ◽  
D. Thusitha U. Abeytunga ◽  
...  
Keyword(s):  
Pleurotus Ostreatus ◽  
Inflammatory Activity ◽  
No Production ◽  
Protective Effects ◽  
Paw Oedema ◽  
Freeze Dried ◽  
Anti Inflammatory ◽  
Rat Paw ◽  
Rat Paw Oedema

Context. Pleurotus ostreatus (P.o) is a culinary mushroom which is commonly called as “oyster mushroom” belonging to the Basidiomycetous fungi of the order Agaricales and family Pleurotaceae. Objectives. The present study investigates the anti-inflammatory potential of P.o and the underlying mechanisms of activity. Materials and Methods. Anti-inflammatory activity was evaluated using suspensions of freeze-dried and powdered (SFDP) P.o and acetone extract (AE) of P.o in normal and alloxan-induced diabetic rats using the carrageenan-induced rat paw oedema model. The mechanisms by which P.o is mediating the anti-inflammatory activity were studied using in vivo and in vitro assays. Results. At doses of 500–1000 mg/kg, the SFDP of P.o showed long-lasting activity at both early and late phases of carrageenan-induced rat paw oedema. The dose of 750 mg/kg showed the most potent inhibitory activity (92% inhibition) in healthy rats. The AE of P.o showed maximum inhibition of oedema of 87%. P.o exerted protective effects on the inflammatory pathologies in rats with diabetes. The possible mechanisms by which P.o mediates the anti-inflammatory activity were antihistamine activity (52.1%), inhibition of cell migration to the site of inflammation (45.4%), in vitro membrane stabilizing activity (52.6%), and inhibition of nitric oxide (NO) production (91.2%) (P<0.05). Dose-dependent inhibition of NO production was seen with in vitro treatment of rat peritoneal cells with AE of P.o (r = 0.95; P<0.05). Discussion and Conclusion. The promising activity of culinary mushroom P.o against inflammation suggests its potential application as a functional food during inflammatory conditions.

scholarly journals In Vitro Effect of Local Anesthetics onCandida albicansGerm Tube Formation

1994 ◽  
Vol 1 (4) ◽  
pp. 193-197 ◽  
Author(s):  
Acácio Rodrigues ◽  
Cidália Pina Vaz ◽  
A. Freitas Fonseca ◽  
J. Martinez de Oliveira ◽  
Henrique Barros
Keyword(s):  
Germ Tube ◽  
Inhibitory Effect ◽  
Tube Formation ◽  
Vaginal Candidiasis ◽  
Sabouraud Agar ◽  
Colony Forming Units ◽  
Vitro Effect ◽  
Phosphate Buffered Saline ◽  
Dose Dependent

Objective:This study was planned to clarify the in vitro effect of lidocaine and bupivacaine on germ tube formation byCandida albicansisolates from cases of clinical vaginal candidiasis.Methods:FourteenC. albicansstrains (clinical vaginal isolates) were grown on Sabouraud agar for 24 h at 37℃ and tested as follows: 100 μl of a yeast suspension [105colony forming units (CFU)/ml of phosphate buffered saline (PBS)] was added to 500 μl of fresh human serum with lidocaine or bupivacaine (pure salts) in serial concentrations. The test was run in duplicate. Controls were prepared for each strain. After 4 h of incubation at 37℃, samples were taken from each vial and 200 yeasts were counted in a counting chamber. The pH of each suspension was measured.Results:The results are given as the mean of the 2 readings and are expressed as the percentage of blastoconidia with germ tubes/total blastoconidia.Conclusions:Our experiments show that both lidocaine and bupivacaine have a dose-dependent inhibitory effect, pH-independent, on germ tube formation byC. albicansand that both drugs seem to be promising in the treatment of genital candidiasis due to the combination of anesthetic and antifungal properties.

scholarly journals Detection and Characterization of Autoagglutination Activity by Campylobacter jejuni

2000 ◽  
Vol 68 (11) ◽  
pp. 6168-6175 ◽  
Author(s):  
Naoaki Misawa ◽  
Martin J. Blaser
Keyword(s):  
Campylobacter Jejuni ◽  
Natural Transformation ◽  
Host Cells ◽  
Vitro Assay ◽  
Sodium Metaperiodate ◽  
Bacterial Hydrophobicity ◽  
Phosphate Buffered Saline ◽  
Common Cell

ABSTRACT In several gram-negative bacterial pathogens, autoagglutination (AAG) activity is a marker for interaction with host cells and virulence. Campylobacter jejuni strains also show AAG, but this property varies considerably among strains. To examine the characteristics of C. jejuni AAG, we developed a quantitative in vitro assay. For strain 81-176, which shows high AAG, activity was optimal for cells grown for ≤24 h, was independent of growth temperature, and was best measured for cells suspended in phosphate-buffered saline at 25°C for 24 h. AAG activity was heat labile and was abolished by pronase or acid-glycine (pH 2.2) treatment but not by lipase, DNase, or sodium metaperiodate. Strain 4182 has low AAG activity, but extraction with water increased AAG, suggesting the loss of an inhibitor. Strain 6960 has weak AAG with no effect due to water extraction. Our study with clinical isolates suggests that C. jejuni strains may be grouped into three AAG phenotypes. A variant derived from strain 81116 that is flagellate but immotile showed the strong AAG exhibited by the parent strain, suggesting that motility per se is not necessary for the AAG activity. AAG correlated with both bacterial hydrophobicity and adherence to INT407 cells. Mutants which lack flagella (flaA,flaB, and flbA) or common cell surface antigen (peb1A) were constructed in strain 81-176 by natural transformation-mediated allelic exchange. Both AAG activity and bacterial hydrophobicity were abolished in the aflagellate mutants but not the peb1A mutant. In total, these findings indicate that C. jejuni AAG is highly associated with flagellar expression.

Fabrication and Characterization of Mechanically Reinforced Collagen Sponge

2005 ◽  
Vol 288-289 ◽  
pp. 385-388
Author(s):  
Yosuke Hiraoka ◽  
Ueda Hiroki ◽  
Yu Kimura ◽  
Yasuhiko Tabata
Keyword(s):  
Cell Attachment ◽  
Average Pore Size ◽  
Collagen Sponge ◽  
Average Pore ◽  
Culture Studies ◽  
Collagen Solution ◽  
Freeze Dried ◽  
Interconnected Pore

This study describes an investigation of collagen sponge mechanically reinforced through the incorporation of poly(glycolic acid)(PGA) fiber. A collagen solution with PGA fiber homogeneously dispersed was freeze-dried, followed by dehydrothermal cross-linking to obtain collagen sponges incorporating PGA fiber. A collagen sponge without PGA fiber was prepared similarly by using the collagen solution. By scanning electron observation, the collagen sponges exhibited isotropic and interconnected pore structures with an average pore size of 180 µm, irrespective of PGA fiber incorporation. As expected, PGA fiber incorporation enabled the collagen sponge to significantly enhance the compression strength. In vitro cell culture studies revealed that the number of L929 fibroblasts initially attached was significantly greater for the collagen sponge incorporating PGA fiber than for the collagen sponge. In vitro cell proliferation studies revealed that the proliferation of cell was higher for the collagen sponge incorporating PGA fiber, by day 21, than the collagen sponge without PGA fiber. It is possible that shrinkage suppression results in the superior cell attachment and proliferation of sponge incorporating PGA fiber. After subcutaneous implantation into the backs of mice, the residual volume of collagen sponge incorporating PGA fiber was significantly large compared with that of collagen sponge. We concluded that the incorporation of PGA fiber is a simple way to reinforce collagen sponge without impairing the biocompatibility.

scholarly journals Ethanolic extract of ocimum kilimandscharicum linnleaves: phytochemical and in vitro pharmacological activity

2021 ◽  
pp. 106-109
Author(s):  
Yamini N ◽  
Lahari S ◽  
Phani deepthi V
Keyword(s):  
In Vitro Model ◽  
Ethanolic Extract ◽  
Clinical Development ◽  
Dependent Manner ◽  
Thrombolytic Activity ◽  
Standard Drug ◽  
Ethanolic Extracts ◽  
Vitro Model ◽  
Dose Dependent

Using an in vitro model, the anti-thrombolytic efficacy of ethanolic extracts of Ocimum kilimandscharicum Linn was investigated. The researchers discovered that different concentrations of the extract had significant anti-thrombolytic activity in a dose-dependent manner , which was comparable to a standard drug. As a result of the presence of flavonoids and polyphenols in the plant extract, it can be concluded that it has a promising future in the treatment of thrombosis. This knowledge will be useful in the clinical development of thrombolytic therapeutics by identifying more potent anti-thrombolytic principles from natural resources..    

scholarly journals Antitumor and Antimicrobial Potential of Manganese(II), Nickel(II) and Copper(II) Complexes of 4-Methoxy Benzohydrazide Derived Schiff Base Ligand

2021 ◽  
Vol 11 (1) ◽  
pp. 3249-3260
Keyword(s):  
Schiff Base ◽  
Metal Complexes ◽  
Schiff Base Ligand ◽  
Antimicrobial Activities ◽  
Molar Ratio ◽  
Gram Positive Bacteria ◽  
Ft Ir ◽  
Dose Dependent

Herein, we describe the synthesis and characterization of a Schiff base ligand (E)-N'-(2-hydroxybenzylidene)-4-methoxybenzohydrazide (HBMB) and its Mn(II), Ni(II), and Cu(II) metal complexes (C1-C3) respectively. The ligand HBMB was synthesized by reacting condensation of salicylaldehyde and 4-methoxy benzohydrazide in a 1:1 molar ratio. The structure of HBMB and its metal complexes (C1-C3) were evaluated by using UV-Vis, FT-IR, 1H-NMR, mass spectroscopy as well as on the basis of elemental analysis, conductivity measurements, and thermogravimetric techniques (TGA). The synthesized molecules' tumoricidal properties were performed against human breast cancer (MCF-7) and colon cancer (HT 29) cell lines. The biological results indicated that the ligand, HBMB, and metal complexes possess dose-dependent selective cytotoxicity against the tested carcinoma cells. The synthesized compounds were further evaluated for their in vitro antimicrobial activities against Gram-positive bacteria (Staphylococcus aureus), Gram-negative bacteria (Escherichia coli), and fungal strains (Aspergillus niger).

355 DEVELOPMENTAL COMPETENCE OF IMMATURE BUBALINE CUMULUS - OOCYTE COMPLEXES VITRIFIED BY THE OPEN PULLED STRAW AND CONVENTIONAL STRAW METHODS

2007 ◽  
Vol 19 (1) ◽  
pp. 293
Author(s):  
A. Sharma ◽  
G. N. Purohit
Keyword(s):  
Morphological Changes ◽  
Developmental Competence ◽  
Control Group ◽  
Equal Concentration ◽  
Nuclear Maturation ◽  
Developmental Capacity ◽  
Phosphate Buffered Saline ◽  
Dose Dependent Increase ◽  
Dose Dependent

The in vitro maturation (IVM), fertilization (IVF), and morphological changes in buffalo cumulus–oocyte complexes (COCs) cryopreserved by ultrarapid freezing using conventional (CON) and open pulled staw (OPS) methods were tested. COCs were cryopreserved using a vitrification solution comprised of Dulbecco&apos;s phosphate-buffered saline+0.5 M sucrose+0.4% BSA and two concentrations (4.5 or 5.5 M) of each cryoprotectant ethylene glycol (EG) and dimethylsulfoxide (DMSO) by either the CON or the OPS method. Vitrified COCs were stored in LN for 7 days and then thawed; morphologically normal COCs were used for IVM (n = 1070) and IVF (n = 933) in 2 separate experiments to record morphological damage of COCs due to vitrification, nuclear maturation 24 h after culture (9 replicates), and fertilization 24 h after insemination (10 replicates). The COCs were matured in vitro in TCM-199 media with hormone supplements and fertilized using TALP-BSA as described previously (Purohit et al. 2005 Anim. Reprod. Sci. 87, 229–239). Freshly collected COCs were separately used for IVM (n = 110) and IVF (n = 130) and kept as controls. The arcsin transformed data of the proportions of oocytes matured or fertilized was compared by Duncan&apos;s new multiple range test. The highest proportion of morphologically normal oocytes was seen in 5.5 M EG with the CON method (94.5%) and the lowest was seen in 4.5 M DMSO with the OPS method (82.4%). At the end of experiment 1, it was apparent that IVM in all vitrification groups was significantly lower (P &lt; 0.05) compared to the control group (66.4%). Among the various vitrification treatments, the highest IVM occurred in 5.5 M EG with the OPS method (39.2%) and the lowest in 4.5 DMSO with the CON method (19.3%). Comparison of both concentrations of EG and DMSO showed that the proportion of COCs attaining Metaphase-II (M-II) increased with increasing concentration of both of the cryoprotectants. However, at equal concentration of EG and DMSO, the proportion of COCs attaining M-II was significantly higher in the OPS method compared to the CON method. In experiment 2, a significantly higher (P &lt; 0.05) IVF was seen for fresh COCs (45.4%) compared to vitrified COCs. Among the vitrification treatments, the highest fertilization was seen in 5.5 M EG with the OPS method (33.6%) and the lowest in 4.5 M DMSO with the CON method (15.17%). A dose-dependent increase in the proportion of oocytes fertilized was seen with increasing concentration of both EG and DMSO [CON: 4.5 M (15.2%), 5.5 M (25.6%); OPS: 4.5 M (21.3%), 5.5 M (27.5%)] in both CON and OPS methods. Comparison of the 2 cryoprotectants revealed that EG was better compared to DMSO.At equal concentrations of EG or DMSO, a significantly higher (P &lt; 0.05) proportion of fertilized oocytes was seen in the OPS method compared to the CON method. It was concluded that vitrification results in some damage to oocytes, with decrease in their subsequent IVM and IVF. Developmental capacity of vitrified buffalo oocytes can be improved by using OPS instead of conventional straws.

scholarly journals A procedure for in vitro evaluation of the immunosuppressive effect of mesenchymal stem cells on activated T cell proliferation

2020 ◽  
Author(s):  
Catalina Marinescu ◽  
Bogdan Preda ◽  
Alexandrina Burlacu
Keyword(s):  
Cell Proliferation ◽  
T Cell ◽  
Inhibitory Effect ◽  
Immunosuppressive Effect ◽  
T Cell Proliferation ◽  
Immunomodulatory Capacity ◽  
Activated T Cell ◽  
Dose Dependent

Abstract Background: Mesenchymal stem/stromal cells (MSC) represent adult cells with multipotent capacity. Besides their capacity to differentiate into multiple lineages in vitro and in vivo, increasing evidence points towards the immunomodulatory capacity of these cells, as an important feature for their therapeutic power. Although not included in the minimal criteria established by the International Society for Cellular Therapy as a defining MSC attribute, demonstration of the immunomodulatory capacity of MSC can be useful for the characterization of these cells before being considered MSC. Here we present a simple and reliable protocol by which the immunosuppressive effect of MSC can be evaluated in vitro. It is based on the measuring of the proliferation of activated T cells cultured in direct contact with irradiated MSC.Results: Our results showed that MSC have a dose-dependent inhibitory effect on activated T cell proliferation, which can be quantified as a percentage of maximum proliferation. Our data shows that batch-to-batch variability can be determined within one or multiple experiments, by extracting the area under curve of T cell proliferation plotted against the absolute number of MSC in co-culture.Conclusions: The validation of the immunomodulatory capacity of MSC could be added to the characterization of the cells before being used in various MSC-based approaches to treat immunological diseases. Our results showed that MSC have a dose-dependent inhibitory effect on activated T cell proliferation. The immunosuppressive properties of MSC vary between batches, but not between different passages of the same batch.

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