Effect of methanol extract of Anacardium occidentale stem bark on agonist-induced contraction in rat uterine muscle

Anacardium occidentale (Ao) is widely used in ethnomedicine and the effect on contractility of the gut and heart muscles of laboratory rodents have been established however, its effect on the contractility of uterine muscle has been rarely researched. The present study investigated the effect of stem bark methanolic extract of Anacardium occidentale (AoME) on Isolated Rat Uterus Strips (IRUS). The Anacardium occidentale methanol extract (AoME) was obtained by solvent extraction. The IRUS were suspended in a bath containing 15 ml of De Jalon's solution through a silk connected to a force transducer. A tension of 1.0 g was applied. The strips were allowed to equilibrate for a period of 60–90 min before the commencement of the experiment. The extract (0.025- 0.3mg/ml) added cumulatively did not modify the normal tonus in most of the IRUS used except in one where it feebly contracted it. However, the contractile responses induced by acetylcholine (10-9 -10-5 M) and oxytocin (10-9 -10-5 M) on the IRUS were almost completely blocked by pre-incubated AoME at a concentration of 0.2 mg/ml. Stem bark methanol extract of Anacardium occidentale shifted the log concentration curve of both agonists to the right. The present results report the antagonistic effects of stem bark methanol extract of Anacardium occidentale on oxytocin and acetylcholine-induced contraction in rat uterus strips. Keywords: Anacardium occidentale, Oxytocin, Acetylcholine, Uterus, Smooth muscle

Effect of Geometrical Parameters On Sensitivity And Volume Of Dual Octal Ring

Force transducer is one of the load cell which is used to measure force or weight, pressure etc. various types of transducers are manufacturing for various applications. But most of strain gauge type of transducer is used. In current research, optimization of octagonal type of force transducer design is carried out by maximizing sensitivity and minimizing the volume. Force transducer is analyze with the help of finite element method and find the critical parameters, its effect also as sensitivity and volume. Response surface methodology is used for experimental set up. For performance of all parameters analysis of variance is carried out and multi-objective optimization is also performed.

VERIFICATION OF FORCE TRANSDUCER FOR DIRECT AND INDIRECT MEASUREMENTS

Paper deals with verification of high load force sensor using the small weight weights. Test band was built for this purpose. Verification of test band were executed using the etalon reference sensor. Small forces were executed via using the direct method through the applying of weights. High forces were executed using the indirect method through the lever amplification of load derived from small weights. Uncertainties of measurement were evaluated.

Kinematic study of a road power generator for the port transport network

Nowadays, energy-saving applications are based on alternative energy sources that enable autonomous powering of electrical consumers. Within the port transport network, 62% of freight transport is carried by road. One solution for the alternative generation of electrical energy for lighting and power supply of small power consumers is the use of road electromechanical systems such as artificial road bumps with an electromagnetic generator that converts the energy of vehicle movement into electrical energy. This article deals with a road power generator transducer with a slider-rocker kinematic pair for converting translational motion into rotational motion. The authors conducted a kinematic study of the actuating force transducer and analysed its performance at various connecting rod lengths with the required speed and dimensional criteria. They determined the effect of the connecting rod length on the trajectory and speed of the rocker arm. Analysis has shown that a connecting rod length of 100 and 150 mm, providing a working section with a uniform increase in speed of the rocker arm, satisfies the specified requirements. For further investigation of the electromechanical power system, the researchers adopted a 100 mm long connecting rod, as this allows the unit to be realised with reduced dimensions.

The mechanical force of minority cells modulates the tumor taxol-resistance and progression

Cancer is a leading cause of death worldwide. The chemotherapy is one of a major treatment for cancer. However, resistance to chemotherapeutic agents is still a crucial problem in cancer therapies. Majority drug resistance results from the accumulation of mutation of genes in the minority-resistant cells. The mechanism underlying the emergence and the development of cancer resistance from minority-resistant cells has not been fully elucidated. Here, we revealed that minority taxol-resistant cancer cells (MRCs) with enhanced mechanical force can transmit the high force to surrounding sensitive cells through force transducer merlin, and thus enhancing the contraction and adhesion strength of tumor cells (termed as mechanoassimilation), which eventually accelerates the development of drug resistance and tumor progression in vivo. In addition, disturbance and reduction of mechanoassimilation in tumor leads them sensitive to taxol again in vitro and in vivo, which also provide a preliminary indication of MRC contribution in drug-resistance and malignancy development through mechanoassimilation, and offer a new opportunity for cancer therapy by targeting the tumor mechanics.

Rat skeletal muscle-nerve preparation to teach skeletal muscle physiology

This sourcebook update describes a variation of a previous sourcebook experiment that used isolated extensor digitorum longus muscle from mouse to teach skeletal muscle properties (Head and Arber, Adv Physiol Educ 37: 405-414, 2013; doi:10.1152/advan.00155.2012). Gastrocnemius-sciatic nerve preparation in an anaesthetized rat was developed and muscle contractions were recorded in a computerized data acquisition system using an isometric force transducer. Teachers and students in physiology or biology can use this preparation to demonstrate skeletal muscle properties like simple muscle twitch, quantal summation, wave summation, superposition, incomplete tetanus, complete tetanus, treppe, fatigue, and length-tension relationship.

Nox4 Knockout Does Not Prevent Diaphragm Atrophy, Contractile Dysfunction, or Mitochondrial Maladaptation in the Early Phase Post-Myocardial Infarction in Mice

Background/Aims: Diaphragm dysfunction with increased reactive oxygen species (ROS) occurs within 72 hrs post-myocardial infarction (MI) in mice and may contribute to loss of inspiratory maximal pressure and endurance in patients. Methods: We used wild-type (WT) and whole-body Nox4 knockout (Nox4KO) mice to measure diaphragm bundle force in vitro with a force transducer, mitochondrial respiration in isolated fiber bundles with an O2 sensor, mitochondrial ROS by fluorescence, mRNA (RT-PCR) and protein (immunoblot), and fiber size by histology 72 hrs post-MI. Results: MI decreased diaphragm fiber cross-sectional area (CSA) (~15%, p = 0.015) and maximal specific force (10%, p = 0.005), and increased actin carbonylation (5-10%, p = 0.007) in both WT and Nox4KO. Interestingly, MI did not affect diaphragm mRNA abundance of MAFbx/atrogin-1 and MuRF-1 but Nox4KO decreased it by 20-50% (p < 0.01). Regarding the mitochondria, MI and Nox4KO decreased the protein abundance of citrate synthase and subunits of electron transport system (ETS) complexes and increased mitochondrial O2 flux (JO2) and H2O2 emission (JH2O2) normalized to citrate synthase. Mitochondrial electron leak (JH2O2/JO2) in the presence of ADP was lower in Nox4KO and not changed by MI. Conclusion: Our study shows that the early phase post-MI causes diaphragm atrophy, contractile dysfunction, sarcomeric actin oxidation, and decreases citrate synthase and subunits of mitochondrial ETS complexes. These factors are potential causes of loss of inspiratory muscle strength and endurance in patients, which likely contribute to the pathophysiology in the early phase post-MI. Whole-body Nox4KO did not prevent the diaphragm abnormalities induced 72 hrs post-MI, suggesting that systemic pharmacological inhibition of Nox4 will not benefit patients in the early phase post-MI.

Techniques to Determine Powder Flow Properties

The goal of the current work was to do an orderly assessment of flow of powders and granules using compendial and non-compendial procedure. Angle of repose, Tapped density, Carr's compressibility file, Bulk density, Hausner’s ratios were assessed. Moreover, flow was described utilizing powder rheometer wherein delicate force transducer screens the forces created as consequence of the sample displacement, another technique FT4 powder rheometer. The Freeman Technology (FT4 powder rheometer) is intended to describe powders undergoing different circumstances in manners that look like wide scale creation climate. Techniques incorporate security and irregular flow rate, compressibility, shear cell, air circulation, porousness, divider contact and union. The FT4 has demonstrated application on the whole powders preparing ventures, including drugs, fine synthetic substances, cosmetics, food, additives and powder covering. The FT4 application connect to filling, hopper flow, Tablet pressure, wet granulation, end point, flow added substance determination and enhancement, moisture impacts, static change, feeding, stirring, separation, caking, processing, Wall grating, grip, hopper configuration etc.