scholarly journals The flavonoid Licochalcone A induces tegumental damages in Schistosoma mansoni and impairs its oviposition in vitro

2021 ◽  
Vol 14 (3) ◽  
pp. 165-172
Author(s):  
Juliane Felicissimo ◽  
◽  
Danielle Marconato ◽  
Nayara Emídio ◽  
Lara Carvalho ◽  
...  
Keyword(s):  
Single Dose ◽  
Intraperitoneal Injection ◽  
Dosage Form ◽  
In Vitro Tests ◽  
Murine Models ◽  
Licochalcone A ◽  
In Vivo Assays ◽  
Significant Difference

In this study, Licochalcone A (LicoA) was investigated in in vitro and in vivo assays. The survival of worms in culture, the pattern of oviposition, the count of intact tubers and the integrity of the coat were adopted in the in vitro tests. After the animals were perfused, the number of worms recovered, their location and the oogram study were the parameters analyzed to signal the existence of potential schistosomicidal activity in vivo. We observed reduction on the survival, integument integrity and reproduction of adult worms in vitro. Murine models did not show a significant difference in the parasitological parameters analyzed that indicate activity against the worms with an oral single dose of 25 mg/ kg of LicoA or two intraperitoneal injection of 50 mg/ kg LicoA. Nevertheless, it is too early to completely exclude the schistosomicide activity of LicoA, considering that the used dosage form could not provide a regular absorption of the drug.

Effect of Treatment with Calcium Antagonists in Vitro and in Vivo on the Contractile Response of Isolated Rat and Human Detrusor Muscle

1996 ◽  
Vol 91 (4) ◽  
pp. 467-474 ◽  
Author(s):  
Ruth A. Elliott ◽  
Robert I. Norman ◽  
Stuart G. Parker ◽  
R. Paul Whitaker ◽  
C. Mark Castleden
Keyword(s):  
Single Dose ◽  
Calcium Antagonists ◽  
Contractile Response ◽  
Detrusor Muscle ◽  
Significant Difference ◽  
Effect Of Treatment ◽  
Human Detrusor ◽  
Isolated Rat

1. The effect of calcium antagonists on the contractile response of human and rat isolated detrusor muscle in vitro was investigated. The effect of treatment with nimodipine on rat detrusor muscle in vivo was also examined. 2. Nimodipine 0.1 μmol/l, nifedipine 0.1 μmol/l, nifedipine 0.25 μmol/l and verapamil 1.5 μmol/l reduced the maximum contractile response of isolated human detrusor muscle to carbachol by 42%, 35%, 41% and 28% respectively (P < 0.01). Verapamil 0.1 μmol/l had no significant effect on contractile response. 3. Nimodipine 0.1 μmol/l reduced the maximum contractile response of isolated rat detrusor muscle in vitro to electrical field stimulation and carbachol by 53% and 84% respectively (P < 0.01). 4. Rats were pretreated with nimodipine for 8 days (5 mg day−1 kg−1) or with a single dose. Serum nimodipine concentrations were higher in rats treated for 8 days. In rats treated with nimodipine for 8 days there was no significant difference in detrusor contractile response compared with controls. However, after one dose of nimodipine the maximum contractile response was significantly reduced compared with controls (P < 0.05). 5. At the concentrations studied, nimodipine had a greater inhibitory effect on the contractile response of isolated human detrusor muscle. Nimodipine significantly reduced the contractile response of rat detrusor muscle in vitro and after a single dose in vivo, but had no significant effect after 8 days' treatment in vivo. It is possible that chronic oral treatment with nimodipine caused an up-regulation of 1,4-dihydropyridine-sensitive calcium channels, which may explain the lack of clinical effect of chronic treatment with calcium antagonists in patients with detrusor instability.

scholarly journals Angiogenesis Assays: A Critical Overview

2003 ◽  
Vol 49 (1) ◽  
pp. 32-40 ◽  
Author(s):  
Robert Auerbach ◽  
Rachel Lewis ◽  
Brenda Shinners ◽  
Louis Kubai ◽  
Nasim Akhtar
Keyword(s):  
Cellular Proliferation ◽  
Chorioallantoic Membrane ◽  
Aortic Ring ◽  
Corneal Neovascularization ◽  
Complex Nature ◽  
In Vitro Tests ◽  
Antiangiogenic Agents ◽  
In Vivo Assays

Abstract Background: Angiogenesis, the formation of new blood vessels, is an integral part of both normal developmental processes and numerous pathologies, ranging from tumor growth and metastasis to inflammation and ocular disease. Angiogenesis assays are used to test efficacy of both pro- and antiangiogenic agents. Methods: Most studies of angiogenesis inducers and inhibitors rely on various models, both in vitro and in vivo, as indicators of efficacy. In this report we describe the principal methods now in use: the in vivo Matrigel plug and corneal neovascularization assays, the in vivo/in vitro chick chorioallantoic membrane (CAM) assay, and the in vitro cellular (proliferation, migration, tube formation) and organotypic (aortic ring) assays. We include description of two new methods, the chick aortic arch and the Matrigel sponge assays. Conclusions: In vitro tests are valuable, can be carried out expeditiously, and lend themselves to quantification, but must be interpreted with extreme caution. In vitro tests are best viewed as providing initial information, subject to confirmation by in vivo assays. Multiple tests should be used to obtain maximum benefit from in vitro tests. In vivo tests are more difficult and time-consuming to perform, thereby limiting the number of tests that can run at any one time. Quantification is generally more difficult as well. However, in vivo assays are essential because of the complex nature of vascular responses to test reagents, responses that no in vitro model can fully achieve.

scholarly journals Evaluation of In Vivo Mutagenicity of Low-Dose Methylene Chloride in Mice

1988 ◽  
Vol 7 (5) ◽  
pp. 699-703 ◽  
Author(s):  
R. Raje ◽  
M. Basso ◽  
T. Tolen ◽  
M. Greening
Keyword(s):  
Methylene Chloride ◽  
Corn Oil ◽  
In Vitro Tests ◽  
Male Mice ◽  
Vaginal Plug ◽  
Significant Difference ◽  
In Vivo Mutagenicity ◽  
Negative Controls

Methylene chloride, a widely used industrial solvent, has been shown to be mutagenic by in vitro tests. The aim of this study was to determine in vivo mutagenicity. Groups of 20 Swiss-Webster (S/W) male mice were injected subcutaneously three times/week with 5 ml/kg of 5% vol/vol or 10% vol/vol solution of methylene chloride in corn oil for 4 weeks, followed by 1 week of no treatment. Other groups of 20 S/W male mice were exposed to airflow of 10 L/min carrying 100, 150, or 200 ppm of methylene chloride daily for 2 hr/day, 5 days/week for 6 weeks. Each study contained appropriate negative controls. Mating was started 1 week later for the injection group and 2 days later for the inhalation group. Each male mouse was mated with a S/W virgin adult female. The mating was allowed to continue for 2 weeks. Presence of a vaginal plug was taken as a sign of successful mating and was designated as day 0 of gestation. On day 17, the females were killed, and the fetuses were removed and processed. Male mice were killed, and the testes were removed, preserved in 10% formalin, and processed. No significant difference in any of the mutagenicity parameters was found between control and treated groups. No microscopic lesions were found in testes of the treated males.

scholarly journals In Vitro and In Vivo Biocompatibility Studies of a Cast and Coated Titanium Alloy

Molecules ◽  
2020 ◽  
Vol 25 (15) ◽  
pp. 3399 ◽  
Author(s):  
Ursula Sommer ◽  
Stephan Laurich ◽  
Lucie de Azevedo ◽  
Katharina Viehoff ◽  
Sabine Wenisch ◽  
...  
Keyword(s):  
Cell Culture ◽  
Titanium Alloy ◽  
Femoral Condyle ◽  
Titanium Implant ◽  
In Vitro Tests ◽  
Large Animal ◽  
Sheep Model ◽  
Significant Difference

The biocompatibility of a cast porous and with a calcium titanate reaction layer functionalized titanium alloy (Ti-6Al-7Nb) was tested by means of cell culture, and a small (rat) and large animal (sheep) model. The uncoated titanium material served as a control. In-vitro tests included the validation of osteoblast-like cells attached to the surface of the material with scanning electron microscopy and immunofluorescence of cytoskeletal actin as well as their osteogenic development, the ability to mineralize, and their vitality. Following the in-vitro tests a small animal (rat) and big animal (sheep) model were accomplished by inserting a cylindrical titanium implant into a drill hole defect in the femoral condyle. After 7, 14, and 30 days (rat) and 6 months (sheep) the condyles were studied regarding histological and histomorphometrical characteristics. Uncoated and coated material showed a good biocompatibility both in cell culture and animal models. While the defect area in the rat is well consolidated after 30 days, the sheep show only little bone inside the implant after 6 months, possibly due to stress shielding. None of the executed methods indicated a statistically significant difference between coated and uncoated material.

Subacute and late cardiovascular sequelae to low doses of gamma radiation

1959 ◽  
Vol 197 (4) ◽  
pp. 725-729
Author(s):  
Durwood J. Smith ◽  
Robert C. Parker ◽  
Calvin Hanna ◽  
Henry E. Curley
Keyword(s):  
Gamma Radiation ◽  
Cardiovascular System ◽  
Whole Body ◽  
In Vitro Tests ◽  
Low Doses ◽  
Significant Difference ◽  
Cardiovascular Performance ◽  
And Control

A battery of in vivo and in vitro tests of cardiovascular performance were used to assess the effects of whole-body gamma radiation (cobalt-60) upon the cardiovascular system of dogs. A new method for study of the pressure-volume relations of isolated surviving arteries is described. Groups of six beagles were exposed to 30 r and 100 r 22 months before death and compared with littermate controls. No differences between irradiated and control dogs could be demonstrated. Eight mongrel dogs received 300 r 30 days before death and were compared with five mongrel controls. The only significant difference observed was in the pressure-volume curves of arteries from irradiated dogs, these vessels having a greater initial tone than control arteries. It is concluded that 30 r and 100 r of whole-body gamma radiation have no demonstrable effect upon the cardiovascular system of dogs irradiated 22 months before study, but that 300 r of gamma radiation does produce a significant abnormality of blood vessels.

Comparison of High Purity Factor IX Concentrates and a Prothrombin Complex Concentrate in a Canine Model of Thrombogenicity

1991 ◽  
Vol 66 (05) ◽  
pp. 609-613 ◽  
Author(s):  
I R MacGregor ◽  
J M Ferguson ◽  
L F McLaughlin ◽  
T Burnouf ◽  
C V Prowse
Keyword(s):  
High Purity ◽  
Time Course ◽  
Prothrombin Complex Concentrate ◽  
Degradation Products ◽  
Canine Model ◽  
Factor Ix ◽  
In Vitro Tests ◽  
Albumin Infusion

SummaryA non-stasis canine model of thrombogenicity has been used to evaluate batches of high purity factor IX concentrates from 4 manufacturers and a conventional prothrombin complex concentrate (PCC). Platelets, activated partial thromboplastin time (APTT), fibrinogen, fibrin(ogen) degradation products and fibrinopeptide A (FPA) were monitored before and after infusion of concentrate. Changes in FPA were found to be the most sensitive and reproducible indicator of thrombogenicity after infusion of batches of the PCC at doses of between 60 and 180 IU/kg, with a dose related delayed increase in FPA occurring. Total FPA generated after 100-120 IU/kg of 3 batches of PCC over the 3 h time course was 9-12 times that generated after albumin infusion. In contrast the amounts of FPA generated after 200 IU/kg of the 4 high purity factor IX products were in all cases similar to albumin infusion. It was noted that some batches of high purity concentrates had short NAPTTs indicating that current in vitro tests for potential thrombogenicity may be misleading in predicting the effects of these concentrates in vivo.

A Comparison of the in Vitro and in Vivo Thrombogenic Activity of Factor IX Concentrates Using Stasis (Wessler) and Non-Stasis Rabbit Models

1980 ◽  
Vol 44 (02) ◽  
pp. 081-086 ◽  
Author(s):  
C V Prowse ◽  
A E Williams
Keyword(s):  
Platelet Rich Plasma ◽  
Thrombus Formation ◽  
Factor Ix ◽  
Coagulation System ◽  
In Vitro Tests ◽  
Clinical Use ◽  
Low Activity

SummaryThe thrombogenic effects of selected factor IX concentrates were evaluated in two rabbit models; the Wessler stasis model and a novel non-stasis model. Concentrates active in either the NAPTT or TGt50 in vitro tests of potential thrombogenicity, or both, caused thrombus formation in the Wessler technique and activation of the coagulation system in the non-stasis model. A concentrate with low activity in both in vitro tests did not have thrombogenic effects in vivo, at the chosen dose. Results in the non-stasis model suggested that the thrombogenic effects of factor IX concentrates may occur by at least two mechanisms. A concentrate prepared from platelet-rich plasma and a pyrogenic concentrate were also tested and found to have no thrombogenic effect in vivo.These studies justify the use of the NAPTT and TGt50 in vitro tests for the screening of factor IX concentrates prior to clinical use.

Inhibition of Fibrinolysis and Fibrinogenolysis in Man: Comparison of ε-Aminocaproic Acid and Kallikrein Inhibitor

1963 ◽  
Vol 10 (01) ◽  
pp. 106-119 ◽  
Author(s):  
E Beck ◽  
R Schmutzler ◽  
F Duckert ◽  
Keyword(s):  
Aminocaproic Acid ◽  
Side Reactions ◽  
In Vitro Tests ◽  
Factor V ◽  
Clinical Use ◽  
Strong Inhibitor ◽  
Kallikrein Inhibitor ◽  
Therapeutic Possibilities

SummaryInhibitor of kallikrein and trypsin (KI) extracted from bovine parotis was compared with ε-aminocaproic acid (EACA): both substances inhibit fibrinolysis induced with streptokinase. EACA is a strong inhibitor of fibrinolysis in concentrations higher than 0, 1 mg per ml plasma. The same amount and higher concentrations are not able to inhibit completely the proteolytic-side reactions of fibrinolysis (fibrinogenolysis, diminution of factor V, rise of fibrin-polymerization-inhibitors). KI inhibits well proteolysis of plasma components in concentrations higher than 2,5 units per ml plasma. Much higher amounts of KI are needed to inhibit fibrinolysis as demonstrated by our in vivo and in vitro tests.Combination of the two substances for clinical use is suggested. Therapeutic possibilities are discussed.

Significance of In-Vitro and In-Vivo Correlation in Drug Delivery System

2018 ◽  
Vol 4 (4) ◽  
pp. 523-531
Author(s):  
Hina Mumtaz ◽  
Muhammad Asim Farooq ◽  
Zainab Batool ◽  
Anam Ahsan ◽  
Ashikujaman Syed
Keyword(s):  
Dosage Form ◽  
Pharmaceutical Preparations ◽  
Pharmacokinetic Profile ◽  
In Vitro Dissolution ◽  
Time Saving ◽  
Pharmaceutical Dosage Form ◽  
Short Period ◽  
Form Development

The main purpose of development pharmaceutical dosage form is to find out the in vivo and in vitro behavior of dosage form. This challenge is overcome by implementation of in-vivo and in-vitro correlation. Application of this technique is economical and time saving in dosage form development. It shortens the period of development dosage form as well as improves product quality. IVIVC reduce the experimental study on human because IVIVC involves the in vivo relevant media utilization in vitro specifications. The key goal of IVIVC is to serve as alternate for in vivo bioavailability studies and serve as justification for bio waivers. IVIVC follows the specifications and relevant quality control parameters that lead to improvement in pharmaceutical dosage form development in short period of time. Recently in-vivo in-vitro correlation (IVIVC) has found application to predict the pharmacokinetic behaviour of pharmaceutical preparations. It has emerged as a reliable tool to find the mode of absorption of several dosage forms. It is used to correlate the in-vitro dissolution with in vivo pharmacokinetic profile. IVIVC made use to predict the bioavailability of the drug of particular dosage form. IVIVC is satisfactory for the therapeutic release profile specifications of the formulation. IVIVC model has capability to predict plasma drug concentration from in vitro dissolution media.

Role of in vivo and in vitro Tests in the Diagnosis of Severe Cutaneous Adverse Reactions (SCAR) to Drug

2019 ◽  
Vol 25 (36) ◽  
pp. 3872-3880 ◽  
Author(s):  
Marcel M. Bergmann ◽  
Jean-Christoph Caubet
Keyword(s):  
Adverse Reactions ◽  
Lymphocyte Transformation ◽  
Stevens Johnson Syndrome ◽  
In Vitro Tests ◽  
High Morbidity ◽  
Patch Tests ◽  
Severe Cutaneous Adverse Reactions ◽  
Cutaneous Adverse Reactions

Severe cutaneous adverse reactions (SCAR) are life-threatening conditions including acute generalized exanthematous pustulosis (AGEP), Stevens-Johnson Syndrome (SJS), toxic epidermal necrolysis (TEN) and drug reaction with eosinophilia and systemic symptoms (DRESS). Diagnosis of causative underlying drug hypersensitivity (DH) is mandatory due to the high morbidity and mortality upon re-exposure with the incriminated drug. If an underlying DH is suspected, in vivo test, including patch tests (PTs), delayed-reading intradermal tests (IDTs) and in vitro tests can be performed in selected patients for which the suspected culprit drug is mandatory, or in order to find a safe alternative treatment. Positivity of in vivo and in vitro tests in SCAR to drug varies depending on the type of reaction and the incriminated drugs. Due to the severe nature of these reactions, drug provocation test (DPT) is highly contraindicated in patients who experienced SCAR. Thus, sensitivity is based on positive test results in patients with a suggestive clinical history. Patch tests still remain the first-line diagnostic tests in the majority of patients with SCAR, followed, in case of negative results, by delayed-reading IDTs, with the exception of patients with bullous diseases where IDTs are still contra-indicated. In vitro tests have shown promising results in the diagnosis of SCAR to drug. Positivity is particularly high when the lymphocyte transformation test (LTT) is combined with cytokines and cytotoxic markers measurement (cyto-LTT), but this still has to be confirmed with larger studies. Due to the rarity of SCAR, large multi-center collaborative studies are needed to better study the sensitivity and specificity of in vivo and in vitro tests.

Sign in / Sign up

Export Citation Format

Share Document