Measurement of axial forces during emptying from the human stomach

1992 ◽  
Vol 263 (2) ◽  
pp. G230-G239 ◽  
Author(s):  
M. J. Vassallo ◽  
M. Camilleri ◽  
C. M. Prather ◽  
R. B. Hanson ◽  
G. M. Thomforde
Keyword(s):  
Axial Force ◽  
Longitudinal Axis ◽  
Force Transducer ◽  
Human Stomach ◽  
In Vitro Studies ◽  
In Vivo Studies ◽  
Dependent Manner ◽  
Axial Forces

Our aim was to measure axial forces in the stomach and to evaluate their relation to circumferential contractions of the gastric walls and the emptying of gastric content. We used a combination of simultaneous radioscintigraphy, gastroduodenal manometry, and an axial force transducer with an inflatable 2-ml balloon fluoroscopically placed in the antrum. In vitro studies demonstrated that the axial force transducer records only antegrade forces along the longitudinal axis of this probe in an intensity-dependent manner. In vivo studies were performed in five healthy subjects for at least 3 h after ingestion of radiolabeled meals. When administered separately, the emptying of liquids or solids from the stomach is associated with generation of antral axial forces and coincident phasic pressure activity; however, almost 20% (average) of gastric axial forces during emptying of liquids or solids are unassociated with proximal or distal antral pressure activity ("isolated" forces). High amplitude antral axial forces and pressures occur during both lag and postlag emptying phases. During emptying of liquids, there is a trend for axial forces to be coincident more often with proximal than with distal antral pressure activity and vice versa for the emptying of solids (P = 0.015). These data suggest that when placed in the antrum, the transducer can semiquantitatively record axial forces during gastric emptying. By combining these observations with the data from in vitro studies, it appears that axial forces predominantly result from traction on the balloon by the longitudinal vector resulting from circumferential gastric contractions. The combination of radioscintigraphy and measurement of antral axial forces is a promising method to evaluate mechanical forces involved in the emptying of the human stomach.

Transplantation of Adipose-derived Cells for Periodontal Regeneration: A Systematic Review

2019 ◽  
Vol 14 (6) ◽  
pp. 504-518 ◽  
Author(s):  
Dilcele Silva Moreira Dziedzic ◽  
Bassam Felipe Mogharbel ◽  
Priscila Elias Ferreira ◽  
Ana Carolina Irioda ◽  
Katherine Athayde Teixeira de Carvalho
Keyword(s):  
Systematic Review ◽  
Animal Models ◽  
Platelet Rich Plasma ◽  
Periodontal Regeneration ◽  
In Vitro Studies ◽  
In Vivo Studies ◽  
Cell Sources ◽  
Study Designs

This systematic review evaluated the transplantation of cells derived from adipose tissue for applications in dentistry. SCOPUS, PUBMED and LILACS databases were searched for in vitro studies and pre-clinical animal model studies using the keywords “ADIPOSE”, “CELLS”, and “PERIODONTAL”, with the Boolean operator “AND”. A total of 160 titles and abstracts were identified, and 29 publications met the inclusion criteria, 14 in vitro and 15 in vivo studies. In vitro studies demonstrated that adipose- derived cells stimulate neovascularization, have osteogenic and odontogenic potential; besides adhesion, proliferation and differentiation on probable cell carriers. Preclinical studies described improvement of bone and periodontal healing with the association of adipose-derived cells and the carrier materials tested: Platelet Rich Plasma, Fibrin, Collagen and Synthetic polymer. There is evidence from the current in vitro and in vivo data indicating that adipose-derived cells may contribute to bone and periodontal regeneration. The small quantity of studies and the large variation on study designs, from animal models, cell sources and defect morphology, did not favor a meta-analysis. Additional studies need to be conducted to investigate the regeneration variability and the mechanisms of cell participation in the processes. An overview of animal models, cell sources, and scaffolds, as well as new perspectives are provided for future bone and periodontal regeneration study designs.

scholarly journals Modulatory Effects of Osthole on Lipopolysaccharides-Induced Inflammation in Caco-2 Cell Monolayer and Co-Cultures with THP-1 and THP-1-Derived Macrophages

Nutrients ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 123
Author(s):  
Natalia K. Kordulewska ◽  
Justyna Topa ◽  
Małgorzata Tańska ◽  
Anna Cieślińska ◽  
Ewa Fiedorowicz ◽  
...  
Keyword(s):  
Gene Expression ◽  
Inflammatory Reaction ◽  
Wide Spectrum ◽  
Cell Monolayer ◽  
In Vivo Studies ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Tnf Α

Lipopolysaccharydes (LPS) are responsible for the intestinal inflammatory reaction, as they may disrupt tight junctions and induce cytokines (CKs) secretion. Osthole has a wide spectrum of pharmacological effects, thus its anti-inflammatory potential in the LPS-treated Caco-2 cell line as well as in Caco-2/THP-1 and Caco-2/macrophages co-cultures was investigated. In brief, Caco-2 cells and co-cultures were incubated with LPS to induce an inflammatory reaction, after which osthole (150–450 ng/mL) was applied to reduce this effect. After 24 h, the level of secreted CKs and changes in gene expression were examined. LPS significantly increased the levels of IL-1β, -6, -8, and TNF-α, while osthole reduced this effect in a concentration-dependent manner, with the most significant decrease when a 450 ng/mL dose was applied (p < 0.0001). A similar trend was observed in changes in gene expression, with the significant osthole efficiency at a concentration of 450 ng/μL for IL1R1 and COX-2 (p < 0.01) and 300 ng/μL for NF-κB (p < 0.001). Osthole increased Caco-2 monolayer permeability, thus if it would ever be considered as a potential drug for minimizing intestinal inflammatory symptoms, its safety should be confirmed in extended in vitro and in vivo studies.

scholarly journals Effect of Synchronous Versus Sequential Regimens on the Pharmacokinetics and Biodistribution of Regorafenib with Irradiation

Pharmaceutics ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 386
Author(s):  
Tung-Hu Tsai ◽  
Yu-Jen Chen ◽  
Li-Ying Wang ◽  
Chen-Hsi Hsieh
Keyword(s):  
Stereotactic Body Radiation Therapy ◽  
In Vivo Studies ◽  
Control Group ◽  
High Dose ◽  
Dependent Manner ◽  
Hep G2 ◽  
Time Curve ◽  
Dose Dependent

This study was performed to evaluate the interaction between conventional or high-dose radiotherapy (RT) and the pharmacokinetics (PK) of regorafenib in concurrent or sequential regimens for the treatment of hepatocellular carcinoma. Concurrent and sequential in vitro and in vivo studies of irradiation and regorafenib were designed. The interactions of RT and regorafenib in vitro were examined in the human hepatoma Huh-7, HA22T and Hep G2 cell lines. The RT–PK phenomenon and biodistribution of regorafenib under RT were confirmed in a free-moving rat model. Regorafenib inhibited the viability of Huh-7 cells in a dose-dependent manner. Apoptosis in Huh-7 cells was enhanced by RT followed by regorafenib treatment. In the concurrent regimen, RT decreased the area under the concentration versus time curve (AUC)regorafenib by 74% (p = 0.001) in the RT2 Gy × 3 fraction (f’x) group and by 69% (p = 0.001) in the RT9 Gy × 3 f’x group. The AUCregorafenib was increased by 182.8% (p = 0.011) in the sequential RT2Gy × 1 f’x group and by 213.2% (p = 0.016) in the sequential RT9Gy × 1 f’x group. Both concurrent regimens, RT2Gy × 3 f’x and RT9Gy × 3 f’x, clearly decreased the biodistribution of regorafenib in the heart, liver, lung, spleen and kidneys, compared to the control (regorafenib × 3 d) group. The concurrent regimens, both RT2Gy × 3 f’x and RT9Gy × 3 f’x, significantly decreased the biodistribution of regorafenib, compared with the control group. The PK of regorafenib can be modulated both by off-target irradiation and stereotactic body radiation therapy (SBRT).

Focus on the therapeutic efficacy of 3BNC117 against HIV-1: In vitro studies, in vivo studies, clinical trials and challenges

2017 ◽  
Vol 52 ◽  
pp. 44-50 ◽  
Author(s):  
Zhi-Jun Liu ◽  
Jing Bai ◽  
Feng-Li Liu ◽  
Xiang-Yang Zhang ◽  
Jing-Zhang Wang
Keyword(s):  
Clinical Trials ◽  
Therapeutic Efficacy ◽  
In Vitro Studies ◽  
In Vivo Studies ◽  
Hiv 1

The Control Of Antithrombotic Prophylaxis And Therapy: A Pro-Coagulant Effect Of Heparin

1981 ◽  
Author(s):  
E Szwarcer ◽  
R Giuliani ◽  
E Martinez Aquino
Keyword(s):  
Blood Coagulation ◽  
Antithrombin Iii ◽  
Fixed Time ◽  
In Vitro Studies ◽  
In Vivo Studies ◽  
Clotting Factors ◽  
Platelet Poor Plasma ◽  
Normal Platelet

For studying heparin effect on blood coagulation and on inhibitors, the drug was added at increasing amounts to a normal platelet poor plasma (PPP), and to plasmas of patients with variable amounts of clotting factors (cirrhotic, pregnant, etc) -IN VITRO STUDIES-, and infused to the same individuals -IN VIVO STUDIES-. Modifications on two clotting assays (KCCT-TT) were compared to heparin potentiating effect on AntiXa (Denson & Bonnar tech).When studied IN VITRO, the sensibility of KCCT, TT, and AntiXa techniques for heparin measurement was similar. IN VIVO, an apparently greater sensibility using AntiXa technique was observed.For determining if this phenomena was related to a specific enhanced potentiating effect of the inhibitor against Xa, exerted by heparin IN VIVO, experiences were repeated IN VITRO and IN VIVO, measuring heparin effect on KCCT, TT, and on the inhibitor, studied against Xa and thrombin. A personal technique was used for the measurement of Antithrombin III heparin potentiating effect, using diluted platelet poor test plasma, heated (56°C 15’) and incubated with thrombin during a fixed time, and reading residual thrombin on citrated human PPP. IN VITRO, all techniques were similar in their ability to show heparin presence.IN VIVO, the potentiating effect of heparin on the inhibitor, measured against Xa or thrombin, was greater than the changes obtained on KCCT or TT.So, AntiXa-Antithrombin III techniques seem to be more sensitive for heparin measurement IN VIVO.This “dissociation” of results in between the potentiating effect on the inhibitor, that is not simultaneously exerted on global coagulation, is interpreted as a heparin pro-coagulant effect, exerted by the drug IN VIVO.

scholarly journals Engineering Silicone Rubbers for In Vitro Studies: Creating AAA Models and ILT Analogues With Physiological Properties

2009 ◽  
Vol 132 (1) ◽  
Author(s):  
T. J. Corbett ◽  
B. J. Doyle ◽  
A. Callanan ◽  
M. T. Walsh ◽  
T. M. McGloughlin
Keyword(s):  
In Vitro Studies ◽  
In Vivo Studies ◽  
Aortic Tissue ◽  
Element Analysis ◽  
Future Design ◽  
Change Behavior ◽  
Physiological Properties ◽  
Diameter Change

In vitro studies of abdominal aortic aneurysm (AAA) have been widely reported. Frequently mock artery models with intraluminal thrombus (ILT) analogs are used to mimic the in vivo AAA. While the models used may be physiological, their properties are frequently either not reported or investigated. This study is concerned with the testing and characterization of previously used vessel analog materials and the development of new materials for the manufacture of AAA models. These materials were used in conjunction with a previously validated injection molding technique to manufacture AAA models of ideal geometry. To determine the model properties (stiffness (β) and compliance), the diameter change of each AAA model was investigated under incrementally increasing internal pressures and compared with published in vivo studies to determine if the models behaved physiologically. A FEA study was implemented to determine if the pressure-diameter change behavior of the models could be predicted numerically. ILT analogs were also manufactured and characterized. Ideal models were manufactured with ILT analog internal to the aneurysm region, and the effect of the ILT analog on the model compliance and stiffness was investigated. The wall materials had similar properties (Einit 2.22 MPa and 1.57 MPa) to aortic tissue at physiological pressures (1.8 MPa (from literature)). ILT analogs had a similar Young’s modulus (0.24 MPa and 0.33 MPa) to the medial layer of ILT (0.28 MPa (from literature)). All models had aneurysm sac compliance (2.62–8.01×10−4/mm Hg) in the physiological range (1.8–9.4×10−4/mm Hg (from literature)). The necks of the AAA models had similar stiffness (20.44–29.83) to healthy aortas (17.5±5.5 (from literature)). Good agreement was seen between the diameter changes due to pressurization in the experimental and FEA wall models with a maximum difference of 7.3% at 120 mm Hg. It was also determined that the inclusion of ILT analog in the sac of the models could have an effect on the compliance of the model neck. Ideal AAA models with physiological properties were manufactured. The behavior of these models due to pressurization was predicted using finite element analysis, validating this technique for the future design of realistic physiological AAA models. Addition of ILT analogs in the aneurysm sac was shown to affect neck behavior. This could have implications for endovascular AAA repair due to the importance of the neck for stent-graft fixation.

scholarly journals Isopsoralen Enhanced Osteogenesis by Targeting AhR/ERα

Molecules ◽  
2018 ◽  
Vol 23 (10) ◽  
pp. 2600 ◽  
Author(s):  
Luna Ge ◽  
Yazhou Cui ◽  
Kai Cheng ◽  
Jinxiang Han
Keyword(s):  
Osteoblast Differentiation ◽  
Estrogen Receptor Alpha ◽  
Biological Effects ◽  
Hormone Deficiency ◽  
In Vivo Studies ◽  
Osteogenic Potential ◽  
Type I ◽  
Dependent Manner

Isopsoralen (IPRN), one of the main effective ingredients in Psoralea corylifolia Linn, has a variety of biological effects, including antiosteoporotic effects. In vivo studies show that IPRN can increase bone strength and trabecular bone microstructure in a sex hormone deficiency-induced osteoporosis model. However, the mechanism underlying this osteogenic potential has not been investigated in detail. In the present study, we investigated the molecular mechanism of IPRN-induced osteogenesis in MC3T3-E1 cells. Isopsoralen promoted osteoblast differentiation and mineralization, increased calcium nodule levels and alkaline phosphatase (ALP) activity and upregulated osteoblast markers, including ALP, runt-related transcription factor 2 (RUNX2), and collagen type I alpha 1 chain (COL1A1). Furthermore, IPRN limited the nucleocytoplasmic shuttling of aryl hydrocarbon receptor (AhR) by directly binding to AhR. The AhR target gene cytochrome P450 family 1 subfamily A member 1 (CYP1A1) was also inhibited in vitro and in vivo. This effect was inhibited by the AhR agonists indole-3-carbinol (I3C) and 3-methylcholanthrene (3MC). Moreover, IPRN also increased estrogen receptor alpha (ERα) expression in an AhR-dependent manner. Taken together, these results suggest that IPRN acts as an AhR antagonist and promotes osteoblast differentiation via the AhR/ERα axis.

IWR-1 Inhibits Collagen-Induced Platelet Activation and Protects against Thrombogenesis

2019 ◽  
Vol 39 (04) ◽  
pp. 392-397
Author(s):  
Wei Wang ◽  
Songqing Lai ◽  
ZiJin Xiao ◽  
Haiyue Yan ◽  
Yongxi Li ◽  
...  
Keyword(s):  
Platelet Activation ◽  
Antiplatelet Agent ◽  
Wnt Signalling ◽  
In Vivo Studies ◽  
Dependent Manner ◽  
Platelet Activity ◽  
Occlusion Time ◽  
Negative Effect

AbstractPlatelets play a crucial role in haemostasis and several pathophysiological processes. Collagen is a main initiator for platelet activation and aggregation. Given that Wnt signalling negatively regulates platelet function, and IWR-1 (a small molecule inhibitor for Wnt signalling) has the potential of inhibiting collagen synthesis, it is essential to investigate whether IWR-1 regulates collagen-induced platelet activation and protects against thrombogenesis. In the present study we found that IWR-1 pretreatment effectively suppressed collagen-induced platelet aggregation in a dose-dependent manner. In addition, IWR-1 also resulted in a decrease of P-selectin and phosphatidylserine surface exposure using fluorescence-activated cell sorting analysis. In vitro studies further revealed that IWR-1 had a negative effect on integrin a2β1 activation and platelet spreading. More importantly, the results from in vivo studies showed that IWR-1 exhibited a robust bleeding diathesis in the tail-bleeding assay and a prolonged occlusion time in the FeCl3-induced carotid injury model. Taken together, current results demonstrate that IWR-1 could effectively block collagen-induced platelet activity in vitro and in vivo, and suggest its candidacy as a new antiplatelet agent.

Digestibility of Native and Modified Starches: In Vitro Studies with Human and Rabbit Pancreatic Amylases and In Vivo Studies in Rabbits

1985 ◽  
Vol 115 (1) ◽  
pp. 93-103 ◽  
Author(s):  
Ping C. Lee ◽  
Stephen P. Brooks ◽  
Ok Kim ◽  
Leo A. Heitlinger ◽  
Emanuel Lebenthal
Keyword(s):  
In Vitro Studies ◽  
In Vivo Studies ◽  
Modified Starches

Effect of Single Dose In Vivo Propranolol Therapy on In Vitro Adhesion of Human SS RBC.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 1234-1234 ◽  
Author(s):  
Laura M. De Castro ◽  
Jude C. Jonassaint ◽  
Jennifer G. Johnson ◽  
Milena Batchvarova ◽  
Marilyn J. Telen
Keyword(s):  
Safety Data ◽  
Study Drug ◽  
Flow Chamber ◽  
In Vivo Studies ◽  
Dependent Manner ◽  
Number Of Patients ◽  
Significant Difference ◽  
Before And After

Abstract Sickle red blood cells (SS RBC) are abnormally adhesive to both endothelial cells (ECs) and components of the extracellular matrix (ECM). Epinephrine (epi) has been shown to elevate cAMP in SS RBC and increase adhesion of SS RBC to ECs in a protein kinase A-dependent manner. In vitro and in vivo studies performed in our lab have led to the hypothesis that adrenergic stimuli such as epi may initiate or exacerbate vaso-occlusion and thus contribute to the association of vaso-occlusive events with physiologic stress. We are conducting a prospective, dose-escalation pilot clinical study to investigate whether in vivo administration of one dose of propranolol either down-regulates baseline SS RBC adhesion in vitro or prevents its upregulation by epi. In addition, this study will provide additional safety data regarding the use of propranolol in normotensive patients with sickle cell disease (SCD). Figure Figure To date, we have completed the first two dose cohorts. 11 subjects (9 SS and 1 Sβ° thalassemia; 7 females, 3 males) have participated. No severe adverse events were noted. Cohorts 1 and 2 had mean pre-propranolol blood pressure (BP) of 116 (5.9 SD)/ 60.4 (3.98 SD) and 106.8 (4.68 SD)/ 58 (3.9 SD), respectively; this difference was not statistically significant. Minimal and asymptomatic changes in BP were noted in both cohorts after drug administration, with biphasic systolic and diastolic BP nadirs at 45 and 240 minutes. No clinically significant changes in heart rate were observed. Adhesion studies were performed using a graduated height flow chamber on the day of RBC collection. RBC adhesion to ECs was studied before and after epi stimulation and was measured at sheer stresses ranging from 1 to 3 dyne/cm2. Baseline adhesion measurements were validated by comparing percent (%) adhesion assayed at 2 different times within 7 days—at screening and before propranolol dose on the study drug day. We observed no significant difference in adhesion at the 2 different time points without propranolol. Comparison of % adhesion of epi-stimulated RBC to ECs before and 1 hour after propranolol showed that propranolol given in vivo significantly inhibited both non-stimulated and epi-stimulated SS RBC adhesion (p=0.04 and p=0.001, respectively). Lastly, comparison of SS RBC adhesion at both drug doses confirmed the drug-related inhibition of adhesion (p&lt;0.004). We conclude that propranolol administered in vivo decreases SS RBC baseline adhesion to ECs and substantially abrogates epi-stimulated adhesion to ECs, as measured in vitro. Although we have thus far studied only a small number of patients and low propranolol doses, we expect to confirm these results with the 3rd cohort, in which a higher dose of propranolol will be used. If our findings continue to show that propranolol can decrease both SS RBC baseline and epi-stimulated adhesion to ECs, study of propranolol on a larger scale would be warranted in order to ascertain its safety and efficacy as an anti-adhesive therapy in SCD.

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