Antinociceptive and anti-inflammatory activities of Hymenaea martiana Hayne (Fabaceae) in mice

Hymenaea martiana is a species popularly known in Northeastern Brazil as “jatobá” and used in folk medicine to treat pain and inflammation. The aim of this work was to evaluate the antinociceptive and anti-inflammatory activity of H. martiana. In the present study, we carried out an investigation about the effects of the crude ethanolic extract (Hm-EtOH) and the ethyl acetate fraction (Hm-AcOEt) in models of nociception and inflammation in mice. Chemical (acetic acid-induced writhing and formalin) and thermal stimuli (hot plate) were used for the evaluation of antinociceptive activity, while for the anti-inflammatory profile paw edema induced by carrageenan was used, along with leukocyte migration to the peritoneal cavity. The presence of the flavonoid astilbin in the samples was characterized through HPLC-DAD-MS analysis. Hm-EtOH and Hm-AcOEt (100, 200 and 400 mg.kg-1, i.p.) significantly reduced the number of abdominal contortions and decreased the paw licking time in the formalin test. In the hot plate, the extract increased the latency time of animals. Hm-EtOH and Hm-AcOEt inhibited significantly the increase in the edema after the administration of carrageenan. Hm-EtOH and Hm-AcOEt inhibited leukocyte migration in the peritonitis test. HPLC-DAD-MS analysis of Hm-EtOH and Hm-AcOEt revealed the presence of the flavonoid astilbin in the samples. According to the results of this study, both Hm-EtOH and Hm-AcOEt have antinociceptive and anti-inflammatory activities, which could be related with the presence of flavonoid in the extracts. The results reinforce the popular use of this plant.

Optimization of Mechanically Assembled Van Der Waals Heterostructure Based On Solution Immersion and Hot Plate Heating

Layers of two-dimensional material are bonded together by van der Waals force, as a result, there is no need to take into consideration of the lattice mismatch in the formation of heterojunction, which is endowed with the characteristics of simple stacking in method, free of limitation to the type of materials and diverse changes. However, although the Van Der Waals heterojunction is relatively easy to stack, it is still difficult to generate inter-layer coupling between the thin crystal layers that form the Van Der Waals heterojunction. In most cases, the stacked heterojunction is simply stacked together without any new effects. Therefore, the realization of heterojunction coupling is a difficult problem to be considered in the process of preparing Van Der Waals heterojunction. In this paper, a method based on solution immersion and hot plate heating is proposed to optimize the mechanical stacking of Van Der Waals heterojunctions. It is found that the heterojunctions prepared by normal mechanical stacking method are usually uncoupled before treatment, but they can be stably coupled after treatment. Our method, simple, fast with low-cost, has been repeatedly verified to have a high success rate of coupling, which is suitable for most experimental groups to use and reproduce.

Analgesic Effect of Ethanolic Extract of Seeds and Leaves of Coriandrum Sativum on Swiss Albino Mice

INTRODUCTION: Pain has been described by the International Association for the Study of Pain as an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage. Although NSAIDS and OPIOIDS are available for the treatment, still pain (chronic) is major problem. The present study was designed to study the analgesic effect of ethanolic extract of Coriandrum sativum using hot plate method and acetic acid induced writhing method in experimental animals (Swiss albino mice). MATERIAL AND METHODS:The analgesic effect of leaves and seeds of Coriandrum sativum was assessed using hot plate method and acetic acid induced writhing method in Swiss albino mice. The animals were treated with the ethanolic extract of leaves and seeds of Coriandrum sativum orally at two doses of 100, 500 mg/kg body weight after electric heat and acetic acid induced pain in mice. RESULTS: The study showed that ethanolic extract of leaves and seeds of Coriandrum sativum presented significant (p<0.05) and (p<0.05) analgesic activity in mice simultaneously. The data were analyzed by one-way ANOVA followed by Dunette's multiple comparison test. The results demonstrate that ethanolic extract of leaves and seeds of Coriandrum sativum has got analgesic potential. CONCLUSION: The results demonstrate that ethanolic extract of leaves and seeds of Coriandrum sativum has got significant analgesic effect.

Analgesic activity of Phong Thap Dan tablets in animal models

Phong thap dan tablets are intended to treat low back pain. This study was carried out to evaluate theanalgesic effects of Phong thap dan tablets in experimental animals. The analgesic effects were evaluated inthree animal models: hot plate, mechanical stimulation and acetic acid-induced writhing test. Mice were dividedinto 4 groups given oral water, control drug (codein phosphate in hot plate and mechanical stimulation tests oraspirin in writhing test), Phong thap dan at 2.88 tablets (1.44 g) or 8.64 tablets (4.32 g)/kg b.w/day, respectively.Our results showed that Phong thap dan tablets at both doses increased the reaction time to thermal stimulation,increased the paw withdrawal latency and the force required to elicit a paw withdrawal and decreased thenumber of acetic acid-induced writhing movements in mice. There was no statistically significant differencebetween 2 doses of Phong thap dan tablets in three animal models. We conclude that Phong thap dan tabletsat the doses of 2.88 tablets and 8.64 tablets/kg b.w/day showed significant analgesic effect in animal models.

CNS Depressant and Analgesic Activities of Thysanolaena maxima Roxb. Available in Bangladesh

In Bangladesh, numerous tribal people of Chittagong Hill Tracts have been using different parts of Thysanolaena maxima Roxb. for many years. The present study was designed to investigate CNS depressant and analgesic activities of methanol extract of the aerial parts of the plant in mice models. CNS depressant activity of the crude extract (200 and 400 mg/kg) was evaluated using open field, hole cross and thiopental-induced sleeping time tests using diazepam as the standard. Analgesic activity was determined using acetic acid-induced writhing and hot plate tests using diclofenac sodium as the standard. The extract showed dose dependent suppression of locomotion in open field and hole cross tests and exerted sedative action in thiopental induced sleeping time. In the open field and the hole-cross tests, maximum CNS depressant activity was observed at 90 min after administration of extract and the standard drug. The extract significantly induced the onset of sleep and prolonged the sleeping time in thiopental induced sleeping test compared to the control group. The extract produced significant (p < 0.05) analgesic activity by inhibiting writhing by 41.89% and 60.81%, at doses of 200 and 400 mg/kg body weight, respectively, which was comparable to the inhibition of diclofenac sodium (73.64%). Additionally, in hot plate test, the extract exhibited a significant (p < 0.05) increase in pain threshold in a dose dependent manner. The findings of the study are encouraging and demands further investigation of other bioactivities with isolation of pure compounds. Dhaka Univ. J. Pharm. Sci. 20(2): 227-233, 2021 (December)

Measurement of thermal conductivity in lightweight concrete produced with ground stone residue

With the advancement of concrete production technologies, such as the development of additives, use of different aggregates, dosing methods, mixing and application equipment, they have contributed to the emergence of concrete with special characteristics, as is the case with light concrete. Given the above, this research continues the experimental studies of structural lightweight concrete with expanded clay (coarse aggregate) developed by Lucas and Azambuja (2020). This research presents the results of mechanical properties at older ages, 28 days 214 days for Trait 1 (AN100%) and Trait 2 (AB20%) compared to the results of 7 days of age, however, the main contribution was the measurement of thermal conductivity with construction of a low-cost prototype in accordance with NBR 15220-4:2005, using the protected hot plate method. The results showed compressive strength values ​​of a minimum of 17,8 MPa at 7 days of age and a maximum of 28,6 MPa at 214 days, values ​​above 17 MPa established by NBR NM 35:1995 at 28 days, as well as the tensile strength by diametrical compression, which also presented values ​​that served as a basis for framing concrete as lightweight and structural. The evaluation of thermal conductivity was performed using a hot plate, in which the results were satisfactory between 0,44 and 0,71 W/(m.k), appropriate values ​​to answer the question of thermal performance, thus as well as complying with the established by ABNT NBR 15220-2:2008.

Water Mediated One-Pot, Stepwise Green Synthesis, Anti-Inflammatory and Analgesic Activities of (3-Amino-1-Phenyl-1H-Benzo[f]Chromen-2-yl) (1H-Indol-3-yl) Methanone Catalysed by L-Proline

Aim: The reactions were carried out by one pot three-component synthesis, 3-cyanoacetylindole (1) on reaction with aromatic aldehydes (2) and β-naphthol (3) in an aqueous medium in presence of L-proline as a catalyst under reflux for 30 min, resulted (3-amino-1-phenyl-1H-benzo[f]chromen-2-yl) (1H-indol-3-yl)methanone (4). The method has many advantages like short reaction times, good yields and simple workup procedure besides being green in nature. Pharmacological evaluation of title compounds was done for anti-inflammatory and analgesic activities. Anti-inflammatory activity was carried carrageenan-induced paw edema model in which indomethacin was used as standard and analgesic activity was evaluated by eddy's hot plate method using diclofenac as standard drug. Background: Benzopyrans or chromenes are an important class of heterocyclic compounds due to their broad spectrum of biological activity and a wide range of applications in medicinal chemistry. The chromene moiety is found in various natural products with interesting biological properties. Chromenes constitute the basic backbone of various types of polyphenols and are widely found in alkaloids, tocopherols, flavonoids and anthocyanins. Indoles are omnipresent in various bioactive compounds like alkaloids, agrochemicals and pharmaceuticals. Objective: To synthesize one-pot stepwise Green synthesis, anti-inflammatory and analgesic activities of 3-amino-1-phenyl-1H-benzo[f]chromen-2-yl) (1H-indol-3-yl)methanones Methods: The acute anti-inflammatory effect was evaluated by carrageenan-induced mice paw edema (Ma Rachchh et al., 2011). Edema was induced by injecting carrageenan (1% w/v, 0.1 ml) in the right hind paw of mice. The test compounds 1-12, indomethacin (10 mg/kg) and the vehicle were administered orally one hour before injection of carrageenan. Paw volume was measured with digital plethysmometer at 0, 30, 60, 90, 120 min after injection. Percentage increase =A-B/ A *100 Results: Carrageenan Induced paw edema model was used for Anti-inflammatory activity in which animals treated with standard (indomethacin) and test compounds showed a significant decrease in the paw edema. Analgesic activity was estimated by using Eddy’s hot plate method; animals were treated with standard (diclofenac) and test compounds showed a significant increase in the reaction time. Conclusion: A green, One-pot, step-wise and three-component synthesis of 3-amino-1-phenyl-1H-benzo[f]chromen-2-yl) (1H-indol-3-yl) methanone was achieved by using water as a solvent, L-proline as catalyst under reflux conditions. The reactions were carried out in eco-friendly conditions with shorter reaction times, easier workup and high yields. Anti-inflammatory activity was evaluated by carrageenan-induced paw edema model where significant anti-inflammatory activity is shown by all the test compounds (4a-l) when compared to standard drug. Analgesic activity was studied by Eddy’s Hot plate method and Test compounds 4e, 4f, 4h, 4i, 4j, 4k, 4l showed significant activities when compared to the reference drug.

Design and evaluation of pharmacological properties of a new 1,3,4-thiadiazolylamide derivative of 2-propylpentanoic acid

Introduction: The use of the pharmacophoric approach is a promising direction for modifying the chemical structure of 2-propylpentanoic (valproic) acid in order to obtain new drugs. Materials and methods: In the experiments on mice, acute toxicity, neurotoxicity, antiepileptic activity and analgesic effect of N-(5-ethyl-1,3,4-thiadiazol-2-yl)-2-propylpentanamide (valprazolamide) were evaluated. LD50 was determined by probit analysis. Neurotoxicity was determined in a rotarod test and a bar test in mice. The effects of valprazolamide on the exploratory behavior of mice in open field test and in a light/dark transition test were evaluated. Its antiepileptic activity was tested in mice against seizures induced by maximal electroshock, pentylenetetrazole (scPTZ); isoniazid, thiosemicarbazide, pilocarpine, and camphor. The analgesic effect was studied in a hot plate test. Results and discussion: N-(5-ethyl-1,3,4-thiadiazol-2-yl)-2-propylpentanamide was obtained by introducing pharmacophores into the structure of 2-propylpentanoic acid: a substituted amide group and an electron-donor domain of 1,3,4-thiadiazole. The LD50 value for intraperitoneal administration of a new 2-propylpentanoic acid: derivative to mice was 924.8 mg/kg, and the TD50 value in the rotarod test and the bar test were 456.7 mg/kg and 546.7 mg/kg, respectively. The suppression of orienting responses in the animals was noted when it was administered in neurotoxic doses. Valprazolamide showed the most antiepileptic activity on models of MES, scPTZ and isoniazid antagonism tests. The ED50 values were 138.4 mg/kg, 74.5 mg/kg, and 126.8 mg/kg, respectively. The therapeutic indices for these models of epilepsy were 6.7; 12.4; 7.3, and protective index – 3.3; 6.1 and 3.6, respectively. In the hot plate test, valprazolamide increased the latency period before a defensive response to a thermal stimulus (ED50 165 mg/kg). Conclusion: N-(5-ethyl-1,3,4-thiadiazol-2-yl)-2-propylpentanamide is a new 1,3,4-thiadiazolylamide derivative of 2-propylpentanoic acid with antiepileptic and analgesic activities, which belongs to the group of low-toxic agents. Graphic abstract N-(5-ethyl-1,3,4-thiadiazol-2-yl)-2-propylpentanamide (3D) LD50=924.8 mg/kg (mice, intraperitoneally) TD50=456.7 mg/kg (rotarod, mice, intraperitoneally) ED50=138.4 mg/kg (MES, mice, intraperitoneally) ED50=74.5 mg/kg (scPTZ, mice, intraperitoneally)

Optically Tunable and Thermally Erasable Terahertz Intensity Modulators Using Dye-Doped Liquid Crystal Cells with Metasurfaces

A terahertz metasurface that is imbedded into a dye-doped liquid crystal (DDLC) cell is fabricated in this work. After the metasurface-imbedded DDLC cell is irradiated with a linearly polarized pump beam, the irradiated cell is measured with a terahertz spectrometer. The irradiation of the pump beam causes the adsorption of the dye on one of the substrates of the cell, scattering incident terahertz waves and decreasing the transmittances of the terahertz metasurface at all the frequencies of its resonance spectrum. In addition, these transmittances decrease with an increase in the irradiation times of the pump beam. The adsorbed dye molecules are erased from the substrate after the cell is heated by a hot plate. The cell has similar spectra before the irradiation of the pump beam and after the heating of the hot plate. The aforementioned results reveal that the metasurface-imbedded DDLC cell is an optically tunable and thermally erasable terahertz intensity modulator. Therefore, this cell has the potential in developing intensity attenuators for terahertz imaging, frequency isolators for terahertz telecommunication, and spatial light modulators for terahertz information encryption and decryption.