Elucidation of the profound antagonism of contractile action of phenylephrine in rat aorta effected by an atypical sympathomimetic decongestant

Eldina Rizvić,Goran Janković,Miroslav M. Savić 대한약리학회 2017 The Korean Journal of Physiology & Pharmacology Vol.21 No.4

Vasoconstrictive properties of sympathomimetic drugs are the basis of their widespread use as decongestants and possible source of adverse responses. Insufficiently substantiated practice of combining decongestants in some marketed preparations, such are those containing phenylephrine and lerimazoline, may affect the overall contractile activity, and thus their therapeutic utility. This study aimed to examine the interaction between lerimazoline and phenylephrine in isolated rat aortic rings, and also to assess the substrate of the obtained lerimazoline-induced attenuation of phenylephrine contraction. Namely, while lower concentrations of lerimazoline (10–6 M and especially 10–7 M) expectedly tended to potentiate the phenylephrine-induced contractions, lerimazoline in higher concentrations (10–4 M and above) unexpectedly and profoundly depleted the phenylephrine concentration-response curve. Suppression of NO with NO synthase (NOS) inhibitor Nw-nitro-L-arginine methyl ester (L-NAME; 10–4 M) or NO scavanger OHB12 (10–3 M), as well as non-specific inhibition of K+-channels with tetraethylammonium (TEA; 10–3 M), have reversed lerimazoline-induced relaxation of phenylephrine contractions, while cyclooxygenase inhibitor indomethacin (10–5 M) did not affect the interaction between two vasoconstrictors. At the receptor level, non-selective 5-HT receptor antagonist methiothepin reversed the attenuating effect of lerimazoline on phenylephrine contraction when applied at 3×10–7 and 10–6 M, but not at the highest concentration (10–4 M). Neither the 5-HT1D-receptor selective antagonist BRL 15572 (10–6 M) nor 5-HT7 receptor selective antagonist SB 269970 (10–6 M) affected the lerimazoline-induced attenuation of phenylephrine activity. The mechanism of lerimazoline-induced suppression of phenylephrine contractions may involve potentiation of activity of NO and K+-channels and activation of some methiothepinsensitive receptors, possibly of the 5-HT2B subtype.

Antifilarial activity of Nigella sativa on Setaria cervi-an in vitro study

Rizvi, Waseem,Kumar, Anil,Rizvi, NH,Ahmad, Razi,Singhal, KC,Khan, Atif Kyung Hee Oriental Medicine Research Center 2005 Oriental pharmacy and experimental medicine Vol.5 No.3

The effect of aqueous and alcoholic extract of seeds of Nigella sativa (N. sativa) was studied on the spontaneous movements of the whole worm (w.w) preparation and nerve muscle (n.m) complex of Setaria cervi (S. cervi). Both the extracts caused inhibition of spontaneous movements of the w.w and n.m complex characterized by initial stimulation followed by irreversible paralysis, with the exception that aqueous extract produced a partially reversible paralysis of w.w preparation. Lesser concentration of both the extracts was required to inhibit the movements of n.m complex than the w.w. Suggesting a cuticular permeability barrier. The lethal concentration $50\;(LC_{50})$ and lethal concentration $90\;(LC_{90})$ were 30 and 55 ng/ml for aqueous and 45 and 60 ng/ml for alcoholic extracts respectively.

Algorithm for Improving the Computing Power of Next Generation Wireless Receivers

Rizvi, Syed S. Korean Institute of Information Scientists and Eng 2012 Journal of Computing Science and Engineering Vol.6 No.4

Next generation wireless receivers demand low computational complexity algorithms with high computing power in order to perform fast signal detections and error estimations. Several signal detection and estimation algorithms have been proposed for next generation wireless receivers which are primarily designed to provide reasonable performance in terms of signal to noise ratio (SNR) and bit error rate (BER). However, none of them have been chosen for direct implementation as they offer high computational complexity with relatively lower computing power. This paper presents a low-complexity power-efficient algorithm that improves the computing power and provides relatively faster signal detection for next generation wireless multiuser receivers. Measurement results of the proposed algorithm are provided and the overall system performance is indicated by BER and the computational complexity. Finally, in order to verify the low-complexity of the proposed algorithm we also present a formal mathematical proof.

Performance Evaluation of Indices-Based Query Optimization from Flash-Based Data Centric Sensor Devices in Wireless Sensor Networks

Rizvi, Sanam Shahla,Chung, Tae Sun SAGE Publications 2012 International journal of distributed sensor networ Vol.2012 No.-

Diagnostic Performance of Hybrid Cardiac Imaging Methods for Assessment of Obstructive Coronary Artery Disease Compared With Stand-Alone Coronary Computed Tomography Angiography : A Meta-Analysis

Rizvi, Asim,Han, Donghee,Danad, Ibrahim,Ó,Hartaigh, Brí,ain,Lee, Ji Hyun,Gransar, Heidi,Stuijfzand, Wijnand J.,Roudsari, Hadi Mirhedayati,Park, Mahn Won,Szymonifka, Jackie,Chang, Hyuk-Jae Elsevier 2018 JACC CARDIOVASCULAR IMAGING Vol.11 No.4

<P><B>Abstract</B></P> <P><B>Objectives</B></P> <P>The current meta-analysis aimed to evaluate the diagnostic performance of hybrid cardiac imaging techniques compared with stand-alone coronary computed tomography angiography (CTA) for assessment of obstructive coronary artery disease (CAD).</P> <P><B>Background</B></P> <P>The usefulness of coronary CTA for detecting obstructive CAD remains suboptimal at present. Myocardial perfusion imaging encompasses positron emission tomography, single-photon emission computed tomography, and cardiac magnetic resonance, which permit the identification of myocardial perfusion defects to detect significant CAD. A hybrid approach comprising myocardial perfusion imaging and coronary CTA may improve diagnostic performance for detecting obstructive CAD.</P> <P><B>Methods</B></P> <P>PubMed and Web of Knowledge were searched for relevant publications between January 1, 2000 and December 31, 2015. Studies using coronary CTA and hybrid imaging for diagnosis of obstructive CAD (a luminal diameter reduction of >50% or >70% by invasive coronary angiography) were included. In total, 12 articles comprising 951 patients and 1,973 vessels were identified, and a meta-analysis was performed to determine pooled sensitivity, specificity, and summary receiver-operating characteristic curves.</P> <P><B>Results</B></P> <P>On a per-patient basis, the pooled sensitivity of hybrid imaging was comparable to that of coronary CTA (91% vs. 90%; p = 0.28). However, specificity was higher for hybrid imaging versus coronary CTA (93% vs. 66%; p < 0.001). On a per-vessel basis, sensitivity for hybrid imaging against coronary CTA was comparable (84% vs. 89%; p = 0.29). Notably, hybrid imaging yielded a specificity of 95% versus 83% for coronary CTA (p < 0.001). Summary receiver-operating characteristic curves displayed improved discrimination for hybrid imaging beyond coronary CTA alone, on a per-vessel basis (area under the curve: 0.97 vs. 0.93; p = 0.047), although not on a per-patient level (area under the curve: 0.97 vs. 0.93; p = 0.132).</P> <P><B>Conclusions</B></P> <P>Hybrid cardiac imaging demonstrated improved diagnostic specificity for detection of obstructive CAD compared with stand-alone coronary CTA, yet improvement in overall diagnostic performance was relatively limited.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Evaluation of antifilarial activity of Berberis aristata roots

Rizvi, Waseem,Kumar, Anil,Ahmad, Razi,Shahid, Mohammad,Shazad, Anwar,Haider, Nakhat Kyung Hee Oriental Medicine Research Center 2008 Oriental pharmacy and experimental medicine Vol.8 No.2

The effect of aqueous and alcoholic extract of roots of Berberis aristata was studied on the spontaneous movements of the whole worm (w.w) preparation and nerve muscle (n.m) complex of cattle filarial parasite Setaria cervi and on the survival of microfilariae. Only aqueous extract could inhibit the spontaneous movements of S. cervi, characterized by initial stimulation followed by reversible paralysis. The concentration required to produce similar effect on n.m complex was less as compared to the w.w. The lethal concentration 50 and lethal concentration 90 for aqueous extract were 48 ng/ml and 65 ng/ml.

Simvastatin-loaded solid lipid nanoparticles for enhanced anti-hyperlipidemic activity in hyperlipidemia animal model

Rizvi, Syed Zaki Husain,Shah, Fawad Ali,Khan, Namrah,Muhammad, Iftikhar,Ali, Khan Hashim,Ansari, Muhammad Mohsin,Din, Fakhar ud,Qureshi, Omer Salman,Kim, Kyoung-Won,Choe, Yeong-Hwan,Kim, Jin-Ki,Zeb, A Elsevier 2019 International journal of pharmaceutics Vol.560 No.-

<P><B>Abstract</B></P> <P>The objective of current study was to develop solid lipid nanoparticles-loaded with simvastatin (SIM-SLNs) and investigate their <I>in vivo</I> anti-hyperlipidemic activity in poloxamer-induced hyperlipidemia model. Nano-template engineering technique was used to prepare SIM-SLNs with palmityl alcohol as lipid core and a mixture of Tween 40/Span 40/Myrj 52 to stabilize the core. The prepared SIM-SLNs were evaluated for physicochemical parameters including particle diameter, surface charge, morphology, incorporation efficiency, thermal behaviour and crystallinity. <I>In vitro</I> release profile of SIM-SLNs in simulated gastric and intestinal fluids was evaluated by using dialysis bag technique and anti-hyperlipidemic activity was assessed in hyperlipidemia rat model. SIM-SLNs revealed uniform particle size with spherical morphology, zeta potential of −24.9 mV and high incorporation efficiency (∼85%). Thermal behaviour and crystallinity studies demonstrated successful incorporation of SIM in the lipid core and its conversion to amorphous form. SIM-SLNs demonstrated a sustained SIM release from the lipid core of nanoparticles. SIM-SLNs significantly reduced the elevated serum lipids as indicated by ∼3.9 and ∼1.5-times decreased total cholesterol compared to those of untreated control and SIM dispersion treated hyperlipidemic rats. In conclusion, SIM-SLNs showed a great promise for improving the therapeutic outcomes of SIM via its effective oral delivery.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Novel Architecture of Self-organized Mobile Wireless Sensor Networks

Rizvi, Syed,Karpinski, Kelsey,Razaque, Abdul Korean Institute of Information Scientists and Eng 2015 Journal of Computing Science and Engineering Vol.9 No.4

Self-organization of distributed wireless sensor nodes is a critical issue in wireless sensor networks (WSNs), since each sensor node has limited energy, bandwidth, and scalability. These issues prevent sensor nodes from actively collaborating with the other types of sensor nodes deployed in a typical heterogeneous and somewhat hostile environment. The automated self-organization of a WSN becomes more challenging as the number of sensor nodes increases in the network. In this paper, we propose a dynamic self-organized architecture that combines tree topology with a drawn-grid algorithm to automate the self-organization process for WSNs. In order to make our proposed architecture scalable, we assume that all participating active sensor nodes are unaware of their primary locations. In particular, this paper presents two algorithms called active-tree and drawn-grid. The proposed active-tree algorithm uses a tree topology to assign node IDs and define different roles to each participating sensor node. On the other hand, the drawn-grid algorithm divides the sensor nodes into cells with respect to the radio coverage area and the specific roles assigned by the active-tree algorithm. Thus, both proposed algorithms collaborate with each other to automate the self-organizing process for WSNs. The numerical and simulation results demonstrate that the proposed dynamic architecture performs much better than a static architecture in terms of the self-organization of wireless sensor nodes and energy consumption.

Beneficial Effects of Fish Liver Preparations of Sea Bass (Lates calcarifer) Versus Gemfibrozil in High Fat Diet-Induced Lipid-Intolerant Rats

F. Rizvi,M. Iftikhar,J.P. George 한국식품영양과학회 2003 Journal of medicinal food Vol.6 No.2

Abnormal lipid metabolism is a main cause of dyslipidemia, which is a major risk factor forcoronary heart disease and obesity and is even linked to diabetic-dyslipide mic complications.Fifteen days of high-fat feeding in Charles Foster rats resulted in a significant increase inbaseline serum lipid levels accompanied by pronounced dyslipidemia. Treatment with fishliver preparations (FLPs) from sea bass and the standard drug gemfibrozil produced a low-ering of serum lipids and glucose levels, along with a fall in very-low-density and low-den-sity lipoprotein and an increase in high-density lipoprotein levels. Simultaneously, reactiva-tion of plasma postheparin lipolytic activity (PHLA) and lecithin:cholesterol acyltransferase(LCAT) activity was also observed. A positive correlation was observed betwen low-densitylipoprotein activity and fecal bile acid excretion, which was enhanced on treatment with FLPsand gemfibrozil, indicating the catabolic process for normal lipids and cholesterol homeo-stasis. These data suggest that FLPs and gemfibrozil not only lower lipid intolerance but alsoreduce diabetic-dyslipide mic complications by activating peroxisome proliferator-activatedreceptors (PAR).123

Evaluation of antifilarial activity of Berberis aristata roots

Waseem Rizvi,NakhatHaider,Anil Kumar,Razi Ahmad,Mohammad Shahid,Anwar Shazad 경희대학교 융합한의과학연구소 2008 Oriental Pharmacy and Experimental Medicine Vol.8 No.2

The effect of aqueous and alcoholic extract of roots of Berberis aristata was studied on the spontaneous movements of the whole worm (w.w) preparation and nerve muscle (n.m) complex of cattle filarial parasite Setaria cervi and on the survival of microfilariae. Only aqueous extract could inhibit the spontaneous movements of S. cervi, characterized by initial stimulation followed by reversible paralysis. The concentration required to produce similar effect on n.m complex was less as compared to the w.w. The lethal concentration 50 and lethal concentration 90 for aqueous extract were 48 ng/ml and 65 ng/ml. The effect of aqueous and alcoholic extract of roots of Berberis aristata was studied on the spontaneous movements of the whole worm (w.w) preparation and nerve muscle (n.m) complex of cattle filarial parasite Setaria cervi and on the survival of microfilariae. Only aqueous extract could inhibit the spontaneous movements of S. cervi, characterized by initial stimulation followed by reversible paralysis. The concentration required to produce similar effect on n.m complex was less as compared to the w.w. The lethal concentration 50 and lethal concentration 90 for aqueous extract were 48 ng/ml and 65 ng/ml.