Development of highly potent melanogenesis inhibitor by in vitro, in vivo and computational studies

Abbas, Qamar,Ashraf, Zaman,Hassan, Mubashir,Nadeem, Humaira,Latif, Muhammad,Afzal, Samina,Seo, Sung-Yum Dove Medical Press 2017 Drug design, development and therapy Vol.11 No.-

<P>The present work describes the synthesis of few hydroxylated amide derivatives as melanogenesis inhibitors. In vitro, in vivo and computational studies proved that compound <B>6d</B> is a highly potent melanogenesis inhibitor compared to standard kojic acid. The title amides <B>4a</B>–<B>e</B> and <B>6a</B>–<B>e</B> were synthesized following simple reaction routes with excellent yields. Most of the synthesized compounds exhibited good mushroom tyrosinase inhibitory activity, but compound <B>6d</B> showed excellent activity (IC<SUB>50</SUB> 0.15 µM) compared to standard kojic acid (IC<SUB>50</SUB> 16.69 µM). Lineweaver–Burk plots were used for the determination of kinetic mechanism, and it was found that compounds <B>4c</B> and <B>6d</B> showed non-competitive inhibition while <B>6a</B> and <B>6b</B> showed mixed-type inhibition. The kinetic mechanism further revealed that compound <B>6d</B> formed irreversible complex with the target enzyme tyrosinase. The <I>Ki</I> values determined for compounds <B>4c</B>, <B>6a</B>, <B>6b</B> and <B>6d</B> are 0.188, 0.84, 2.20 and 0.217 µM respectively. Results of human tyrosinase inhibitory activity in A375 human melanoma cells showed that compound <B>6d</B> exhibited 91.9% inhibi-tory activity at a concentration of 50 µg/mL. In vivo cytotoxicity evaluation of compound <B>6d</B> in zebrafish embryos showed that it is non-toxic to zebrafish. Melanin depigmentation assay performed in zebrafish indicated that compound <B>6d</B> possessed greater potential in decreasing melanin contents compared to kojic acid at the same concentration. Computational studies also supported the wet lab findings as compound <B>6d</B> showed a highest binding affinity with the target protein (PDBID: 2Y9X) with a binding energy value of −7.90 kcal/mol. Molecular dynamic simulation studies also proved that amide <B>6d</B> formed the most stable complex with tyrosinase. Based upon our in vitro, in vivo and computational studies, we propose that compound <B>6d</B> is a promising candidate for the development of safe cosmetic agent.</P>

Synthesis and enzyme inhibitory kinetics of some novel 3-(substituted benzoyl)-2-thioxoimidazolidin-4-one derivatives as α-glucosidase/α-amylase inhibitors

Qamar, Rabia,Saeed, Aamer,Saeed, Maria,Shah, Babar Hussain,Ashraf, Zaman,Abbas, Qamar,Seo, Sung Yum Springer-Verlag 2018 Medicinal Chemistry Research Vol.27 No.5

Performance evaluation of novel solarpowered domestic air cooler with Peltier modules

Zafar Abbas,A. N. Shah,M. Tahir Hassan,M. Sarfraz Ali,Qamar ud Din,Bilal Naseem,Ammar Asghar,Ali Haider 대한기계학회 2020 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.34 No.11

Shifting of air conditioning and ventilation plants from conventional to renewable energy systems is one of the effective ways to save energy and attain sustainability. In this experimental study, an effort has been made to design, fabricate, and evaluate the cooling performance of a solar-powered domestic air cooler with Peltier plates to meet the comfort criteria as per ASHRAE standards. It also investigates the effect of Peltier modules on the performance of conventional room air cooler. The experiments were conducted in a 12x12 room with one, two, three, and four Peltier modules operating at various ambient temperatures. The experiments were repeated three times at specified conditions. Peltier effect was used to decrease water temperature, and subsequently cooled water was used to decrease the temperature of the air after coming in contact with this water. The cooled air was then used to create a comfort zone. The results indicated a decrease in temperature of the experimental zone by 5 %, 13 %, 19 %, and 23 % using one, two, three, and four Peltier modules respectively. The increase in relative humidity was recorded as 5 % at 27 °C temperature of the experimental zone. The results of energy analysis showed a substantial amount of energy savings in this study and suggest that more than 200 MW energy can be saved by replacing conventional electric air coolers all over the country with proposed Peltier based domestic solar powered air cooler.

Erratum to "Marine Sponges as a Drug Treasure" [Biomol.Ther. 24 (2016) 347-362]

Anjum, Komal,Abbas, Syed Qamar,Shah, SayedAsmat Ali,Akhter, Najeeb,Batool, Sundas,Hassan, Syed Shams ul The Korean Society of Applied Pharmacology 2016 Biomolecules & Therapeutics(구 응용약물학회지) Vol.24 No.5

Marine Sponges as a Drug Treasure

Anjum, Komal,Abbas, Syed Qamar,Shah, Sayed Asmat Ali,Akhter, Najeeb,Batool, Sundas,Hassan, Syed Shams ul The Korean Society of Applied Pharmacology 2016 Biomolecules & Therapeutics(구 응용약물학회지) Vol.24 No.4

Marine sponges have been considered as a drug treasure house with respect to great potential regarding their secondary metabolites. Most of the studies have been conducted on sponge's derived compounds to examine its pharmacological properties. Such compounds proved to have antibacterial, antiviral, antifungal, antimalarial, antitumor, immunosuppressive, and cardiovascular activity. Although, the mode of action of many compounds by which they interfere with human pathogenesis have not been clear till now, in this review not only the capability of the medicinal substances have been examined in vitro and in vivo against serious pathogenic microbes but, the mode of actions of medicinal compounds were explained with diagrammatic illustrations. This knowledge is one of the basic components to be known especially for transforming medicinal molecules to medicines. Sponges produce a different kind of chemical substances with numerous carbon skeletons, which have been found to be the main component interfering with human pathogenesis at different sites. The fact that different diseases have the capability to fight at different sites inside the body can increase the chances to produce targeted medicines.

Computational modeling and biomarker studies of pharmacological treatment of Alzheimer's disease

Hassan, Mubashir,Abbas, Qamar,Seo, Sung-Yum,Shahzadi, Saba,Ashwal, Hany Al,Zaki, Nazar,Iqbal, Zeeshan,Moustafa, Ahmed A. SPANDIDOS PUBLICATIONS 2018 MOLECULAR MEDICINE REPORTS Vol.18 No.1

<P>Alzheimer's disease (AD) is a complex and multifactorial disease. In order to understand the genetic influence in the progression of AD, and to identify novel pharmaceutical agents and their associated targets, the present study discusses computational modeling and biomarker evaluation approaches. Based on mechanistic signaling pathway approaches, various computational models, including biochemical and morphological models, are discussed to explore the strategies that may be used to target AD treatment. Different biomarkers are interpreted on the basis of morphological and functional features of amyloid β plaques and unstable microtubule-associated tau protein, which is involved in neurodegeneration. Furthermore, imaging and cerebrospinal fluids are also considered to be key methods in the identification of novel markers for AD. In conclusion, the present study reviews various biochemical and morphological computational models and biomarkers to interpret novel targets and agonists for the treatment of AD. This review also highlights several therapeutic targets and their associated signaling pathways in AD, which may have potential to be used in the development of novel pharmacological agents for the treatment of patients with AD. Computational modeling approaches may aid the quest for the development of AD treatments with enhanced therapeutic efficacy and reduced toxicity.</P>

Protocol-Aware Radio Frequency Jamming inWi-Fi and Commercial Wireless Networks

Hussain, Abid,Saqib, Nazar Abbas,Qamar, Usman,Zia, Muhammad,Mahmood, Hassan The Korea Institute of Information and Commucation 2014 Journal of communications and networks Vol.16 No.4

Radio frequency (RF) jamming is a denial of service attack targeted at wireless networks. In resource-hungry scenarios with constant traffic demand, jamming can create connectivity problems and seriously affect communication. Therefore, the vulnerabilities of wireless networks must be studied. In this study, we investigate a particular type of RF jamming that exploits the semantics of physical (PHY) and medium access control (MAC) layer protocols. This can be extended to any wireless communication network whose protocol characteristics and operating frequencies are known to the attacker. We propose two efficient jamming techniques: A low-data-rate random jamming and a shot-noise based protocol-aware RF jamming. Both techniques use shot-noise pulses to disrupt ongoing transmission ensuring they are energy efficient, and they significantly reduce the detection probability of the jammer. Further, we derived the tight upper bound on the duration and the number of shot-noise pulses for Wi-Fi, GSM, and WiMax networks. The proposed model takes consider the channel access mechanism employed at the MAC layer, data transmission rate, PHY/MAC layer modulation and channel coding schemes. Moreover, we analyze the effect of different packet sizes on the proposed jamming methodologies. The proposed jamming attack models have been experimentally evaluated for 802.11b networks on an actual testbed environment by transmitting data packets of varying sizes. The achieved results clearly demonstrate a considerable increase in the overall jamming efficiency of the proposed protocol-aware jammer in terms of packet delivery ratio, energy expenditure and detection probabilities over contemporary jamming methods provided in the literature.

Erratum to "Marine Sponges as a Drug Treasure"

( Komal Anjum ),( Syed Qamar Abbas ),( Sayedasmat Ali Shah ),( Najeeb Akhter ),( Sundas Batool ),( Syed Shams Ul Hassan ) 한국응용약물학회 2016 Biomolecules & Therapeutics(구 응용약물학회지) Vol.24 No.5

Marine Sponges as a Drug Treasure

( Komal Anjum ),( Syed Qamar Abbas ),( Sayed Asmat Ali Shah ),( Najeeb Akhter ),( Sundas Batool ),( Syed Shams Ul Hassan ) 한국응용약물학회 2016 Biomolecules & Therapeutics(구 응용약물학회지) Vol.24 No.4

Marine sponges have been considered as a drug treasure house with respect to great potential regarding their secondary metabolites. Most of the studies have been conducted on sponge’s derived compounds to examine its pharmacological properties. Such compounds proved to have antibacterial, antiviral, antifungal, antimalarial, antitumor, immunosuppressive, and cardiovascular activity. Although, the mode of action of many compounds by which they interfere with human pathogenesis have not been clear till now, in this review not only the capability of the medicinal substances have been examined in vitro and in vivo against serious pathogenic microbes but, the mode of actions of medicinal compounds were explained with diagrammatic illustrations. This knowledge is one of the basic components to be known especially for transforming medicinal molecules to medicines. Sponges produce a different kind of chemical substances with numerous carbon skeletons, which have been found to be the main component interfering with human pathogenesis at different sites. The fact that different diseases have the capability to fight at different sites inside the body can increase the chances to produce targeted medicines.

Applications of Chondrocyte-Based Cartilage Engineering: An Overview

Phull, Abdul-Rehman,Eo, Seong-Hui,Abbas, Qamar,Ahmed, Madiha,Kim, Song Ja Hindawi Publishing Corporation 2016 BioMed research international Vol.2016 No.-

<P>Chondrocytes are the exclusive cells residing in cartilage and maintain the functionality of cartilage tissue. Series of biocomponents such as different growth factors, cytokines, and transcriptional factors regulate the mesenchymal stem cells (MSCs) differentiation to chondrocytes. The number of chondrocytes and dedifferentiation are the key limitations in subsequent clinical application of the chondrocytes. Different culture methods are being developed to overcome such issues. Using tissue engineering and cell based approaches, chondrocytes offer prominent therapeutic option specifically in orthopedics for cartilage repair and to treat ailments such as tracheal defects, facial reconstruction, and urinary incontinence. Matrix-assisted autologous chondrocyte transplantation/implantation is an improved version of traditional autologous chondrocyte transplantation (ACT) method. An increasing number of studies show the clinical significance of this technique for the chondral lesions treatment. Literature survey was carried out to address clinical and functional findings by using various ACT procedures. The current study was conducted to study the pharmacological significance and biomedical application of chondrocytes. Furthermore, it is inferred from the present study that long term follow-up studies are required to evaluate the potential of these methods and specific positive outcomes.</P>