Studies on the antihypertensive and antidyslipidemic activities of Viola odorata leaves extract

<p>Abstract</p> <p>Background</p> <p>This study was undertaken to provide pharmacological basis for the medicinal use of <it>Viola odorata </it>Linn. in hypertension and dyslipidemia using the <it>in vivo </it>and <it>in vitro </it>assays.</p> <p>Results</p> <p><it>Viola odorata </it>leaves extract (Vo.Cr), which tested positive for alkaloids, saponins, tannins, phenolics, coumarins and flavonoids, caused a dose-dependent (0.1-1.0 mg/kg) decrease in mean arterial blood pressure in anaesthetized rats. In isolated guinea-pig atria, Vo.Cr equally inhibited force and rate of spontaneous atrial contractions. On the baseline of rat thoracic aortae (endothelium-intact and denuded), the plant extract caused phentolamine-sensitive vasoconstriction. When tested on phenylephrine (PE, 1 μM) and K⁺(80 mM)-induced vasoconstriction, Vo.Cr caused a concentration-dependent relaxation and also caused a rightward shift of Ca⁺⁺concentration-response curves as well as suppression of PE (1 μM) control peaks in Ca⁺⁺-free medium, similar to that caused by verapamil. In the presence of L-NAME, the relaxation curve of Vo.Cr was partially inhibited showing involvement of Nitric oxide (NO) mediated pathway. In Tyloxapol-induced dyslipidemia, Vo.Cr caused reduction in total cholesterol and triglyceride levels. In high-fat diet-induced dyslipidemia model, the plant extract caused a significant decrease in total cholesterol, LDL-C, atherogenic index and prevented the increase in average body weights, while it increased HDL-C.</p> <p>Conclusions</p> <p>These data indicate that the vasodilator effect of the plant extract is mediated through multiple pathways like inhibition of Ca⁺⁺influx via membranous Ca⁺⁺channels, its release from intracellular stores and NO-mediated pathways, which possibly explain the fall in BP. The plant also showed reduction in body weight and antidyslipidemic effect which may be due to the inhibition of synthesis and absorption of lipids and antioxidant activities. Thus, this study provides a pharmacologic rationale to the medicinal use of <it>Viola odorata </it>in hypertension and dyslipidemia.</p

Ranking diffusion-MRI models with in-vivo human brain data

Diffusion MRI microstructure imaging provides a unique non-invasive probe into the microstructure of biological tissue. Its analysis relies on mathematical models relating microscopic tissue features to the MR signal. This work aims to determine which compartment models of diffusion MRI are best at describing the signal from in-vivo brain white matter. Recent work shows that three compartment models, including restricted intra-axonal, glial compartments and hindered extra-cellular diffusion, explain best multi b-value data sets from fixed rat brain tissue. Here, we perform a similar experiment using in-vivo human data. We compare one, two and three compartment models, ranking them with standard model selection criteria. Results show that, as with fixed tissue, three compartment models explain the data best, although simpler models emerge for the in-vivo data. We also find that splitting the scanning into shorter sessions has little effect on the models fitting and that the results are reproducible. The full ranking assists the choice of model and imaging protocol for future microstructure imaging applications in the brain

Perspectives of plantation forests in the sustainable forest development of China

Modern forestry is gradually moving towards man-made forests on a large scale. Plantations with advanced forestry system have been introduced with the goal of sustainable forestry development and to enhance social, ecological, and economic benefits. Forest plantations with native and exotic species have been established in China and worldwide with shorter rotation cycles than natural forests. In this paper, we discuss the role and perspectives of plantation forests in the Chinese sustainable forest development, the evolution of various plantation programs, the ecological effects of plantations, and the measures to improve plantation forestry. The Chinese government has given substantial importance to nurturing plantation forest resources through various large scale afforestation programs. In 2019, the total area covered by plantations in China reached 79.54 million ha, with a stock volume of 3.39 billion m³ (59.30 m³ per ha); coniferous forests (26.11 million ha, 32.83%) and broad-leaved forests (26.45 million ha, 33.25%) are the dominant types. Plantations have been primarily distributed in the central and southern parts of the country. Plantations with fast-growing and high-yielding tree species facilitated Chinese afforestation activities and improved the administration of forest production, which effectively boosted the forest industry. Plantation forest resources offer many potential productive, economic, and social advantages, though they are also associated with a loss of biodiversity and climate change makes them likely susceptible to disease and insect attack. Appropriate forest management practices during planning, execution, and maintenance of plantations can contribute to the conservation, promotion, and restoration of biodiversity, with the final aim of attaining a balance between having forest plantations and natural forests.We thank the great help from two anonymous reviews. We also thank our friend Chris Ijeoma for the grammar checking of the manuscript. The funding sources included the Postdoctoral research funding of Central South University of Forestry and Technology, Changsha, China (70702-4520 0003

Optimal power flow and unified control strategy for multi-terminal HVDC systems

© 2019 IEEE. This paper presents an automation strategy for multi-terminal HVDC (MT-HVDC) systems combining a dc optimal power flow (dc OPF) routine and a unified reference controller (URC). In the presented automatic framework, the dc OPF algorithm is implemented at the power dispatch center (PDC) of the MT-HVDC system to find optimal reference operation points of the power converters to minimize the losses during the operation of the MT-HVDC grid and solves the contradiction between minimizing losses and preventing commutation failure. At the local control systems, the operating points of the voltage-source converter (VSC) stations are tuned based on the calculations executed in the PDC, which enables fast response to power fluctuation and ensures a stable dc voltage. However, if the communication between the two control layers is lost, the MT-HVDC grid remains stable based on the pre-defined $V$-$P$ droop characteristics for the power converter stations till the connection establishes again, and a set of new operating points is generated and sent. The static and dynamic simulations conducted on the CIGRE B4 HVDC test grid establish the efficient and effective grid control performance with the proposed automation strategy. The analysis shows that the proposed control scheme achieves the desired minimum losses while, at the same time, satisfying the system constraints

Protuupalno i analgetsko djelovanje ekstrakta cijele biljke Fumaria indica na eksperimentalnim životinjama

The 50% ethanolic extract of Fumaria indica was investigated for its anti-inflammatory and antinociceptive potential in animal models. Oral administration of F. indica dry extract (100, 200 and 400 mg kg1) exhibited dose dependent and significant anti-inflammatory activity in acute (carrageenean and histamine induced hind paw oedema – p < 0.05) and chronic (cotton pellet granuloma models of inflammation – p < 0.01). The extract (400 mg kg1) exhibited maximum anti-inflammatory effects of 42.2 and 42.1% after 3 h with carrageenean and histamine respectively. The same dose of extract showed 38.9% reduction in granuloma mass in a chronic condition. A significant anti-nociceptive activity was evidenced in mice; 6.6–67.7% (p < 0.01) protection in mechanical, 33.9–125.1% (p < 0.05) protection in thermal induced pain and 22.2–73.9% (p < 0.05) protection in acetic acid-induced writhing.Na animalnom modelu ispitivano je protuupalno i analgetsko djelovanje ekstrakta biljke Fumaria indica sa 50%-tnim etanolnom. Peroralna primjena suhog ekstrakta F. indica (100, 200 i 400 mg kg1) pokazuje značajno i o dozi ovisno protuupalno djelovanje na akutni (edem šape uzrokovan karagenom i histaminom – p < 0.05) i kronični upalni proces (granulomi uzrokovani pamučnim peletama – p < 0.01). Najveći protuupalni učinak u karagenskom, odnosno histaminskom testu od 42,2 i 42,1% dobiven je s dozom 400 mg kg1 nakon 3 h. Ista doza ekstrakta pokazala je 38,9% smanjenje mase granuloma. Značajno analgetsko djelovanje dokazano je pokusima na miševima: 6,6–67,7% (p < 0,01) zaštita od mehanički izazvane boli, 33,9–125,1% (p < 0,05) zaštita od termički izazvane boli i 22,2–73,9% (p < 0,05) zaštita od kemijski izazvane boli octenom kiselinom

Studies on two polyherbal formulations (ZPTO and ZTO) for comparison of their antidyslipidemic, antihypertensive and endothelial modulating activities

Background Cardiovascular disorders (CVDs) are the leading cause of disease burden worldwide. Apart from available synthetic drugs used in CVDs, there are many herbal formulations including POL-10 (containing 10 herbs), which have been shown to be effective in animal studies but POL-10 was found to cause tachycardia in rodents as its side effect. This study was designed to modify the composition of POL-10 for better efficacy and/or safety profile in CVDs. Methods To assess the antidyslipidemic, antihypertensive and endothelial modulatory properties of two herbal formulations, (ZPTO and ZTO) containing Z: Zingiber officinalis, P: Piper nigrum, T: Terminalia belerica and O: Orchis mascula, different animal models including, tyloxapol and high fat diet-induced dyslipidemia and spontaneously hypertensive rats (SHR) were used. Effect on endothelial function was studied using isolated tissue bath set up coupled with PowerLab data acquisition system. The antioxidant activity was carried out using DPPH radical-scavenging assay. Results Based on preliminary screening of the ingredients of POL-10 in tyloxapol-induced hyperlipidemic rats, ZPTO and ZTO containing four active ingredients namely; Z, P, T and O were identified for further studies and comparison. In tyloxapol-induced hyperlipidemic rats, both ZPTO and ZTO caused significant reduction in serum triglyceride (TG) and total cholesterol (TC). In high fat diet-fed rats, ZPTO decreased TC, low-density lipoproteins cholesterol (LDL-C) and atherogenic index (AI). ZTO also showed similar effects to those of ZPTO with additional merits being more effective in reducing AI, body weight and more importantly raising high-density lipoproteins. In SHR, both formulations markedly reduced systolic blood pressure, AI and TG levels, ZTO being more potent in reversing endothelial dysfunction while was devoid of cardiac stimulatory effect. In addition, ZTO also reduced LDL-C and improved glucose levels in SHR. In DPPH radical-scavenging activity test, ZTO was also more potent than ZPTO. Conclusion The modified formulation, ZTO was not only found more effective in correcting cardiovascular abnormalities than ZPTO or POL-10 but also it was free from tachycardiac side-effect, which might be observed because of the presence of Piper nigrum in ZPTO

Ward Identities, B-> \rho Form Factors and |V_ub|

The exclusive FCNC beauty semileptonic decay B-> \rho is studied using Ward identities in a general vector meson dominance framework, predicting vector meson couplings involved. The long distance contributions are discussed which results to obtain form factors and |V_ub|. A detailed comparison is given with other approaches.Comment: 30 pages+four postscript figures, an Appendix adde

Reliability of Optical Coherence Tomography Angiography Retinal Blood Flow Analyses

PURPOSE: Investigate the association between the optical coherence tomography angiography (OCTA) metrics derived from different analysis programs to understand the comparability of studies using these different approaches. METHODS: Secondary analysis of a prospective observational study (March 2018-September 2021). Forty-four right eyes and 42 left eyes from 44 patients were included. Patients were either undergoing upper gastrointestinal surgery with a critical care stay planned or were already in the critical care unit with sepsis. OCTA scans were obtained in an ophthalmology department or critical care setting. Fourteen OCTA metrics were compared within and between the programs, and agreement was measured by Pearson's R coefficient and intraclass correlation coefficient. RESULTS: Correlation was highest between all Heidelberg metrics and Fractalyse (all >0.84), and lowest between Matlab skeletonized or foveal avascular zone metrics and all other measures (e.g., skeletal fractal dimension and vessel density at -0.02). Agreement between eyes was moderate to excellent in all metrics (0.60-0.90). CONCLUSIONS: The significant variability between metrics and programs used for OCTA analysis demonstrates that they are not interchangeable and supports a recommendation for perfusion density metrics to be reported as standard. TRANSLATIONAL RELEVANCE: Agreement between different OCTA analyses is variable and not interchangeable. The high agreement between non-skeletonized vessel density metrics suggests that these should be routinely reported