Lahore, Pakistan
Lahore, Pakistan

Time filter

Source Type

Pervez H.,Bahauddin Zakariya University | Saira N.,Bahauddin Zakariya University | Iqbal M.S.,FC College | Yaqub M.,Bahauddin Zakariya University | Khan K.M.,University of Karachi
Medicinal Chemistry Research | Year: 2013

A series of N 4-aryl-substituted 5-fluoroisatin-3- thiosemicarbazones 3a-3l was synthesized and evaluated for selected biological activities. The brine shrimp lethality bioassay was carried out to study their in vitro cytotoxicity potential and besides, their antifungal, phytotoxic and urease inhibitory effects were also investigated. Seven compounds i.e. 3a, 3d, 3f, 3g, 3h, 3j and 3k proved to be active in the brine shrimp assay, displaying promising cytotoxicity (LD50 = 6.89 × 10-5-2.79 × 10-4 M). Amongst these, 3a and 3h were found to be the most active ones (LD50 = 6.89 × 10-5 and 9.79 × 10-5 M, respectively). Compounds 3i, 3j and 3 k displayed moderate (40 %) antifungal activity against one or two fungal strains i.e. A. flavus and/or M. canis. In phytotoxicity assay, all the synthesized compounds, including the reference point 2m showed weak-to-moderate (15-70 %) activity at the highest tested concentration (500 μg/mL). In urease inhibition assay, compounds 3f, 3g and 3j proved to be the most potent inhibitors, demonstrating relatively a higher degree of enzymatic inhibition with IC50 values ranging from 37.7 to 47.3 μM. © 2013 Springer Science+Business Media New York.


Pervez H.,Bahauddin Zakariya University | Saira N.,Bahauddin Zakariya University | Iqbal M.S.,FC College | Yaqub M.,Bahauddin Zakariya University | Khan K.M.,University of Karachi
Molecules | Year: 2011

A series of twenty one N4-aryl substituted 5-trifluoromethoxyisatin-3- thiosemicarbazones 3a-3u was synthesized by the reaction of trifluoromethoxyisatin 1 with different arylthiosemicarbazides 2 in aqueous ethanol (50%), containing a few drops of acetic acid. Their structures were established on the basis of analytical (CHN) and spectral (IR, 1H-NMR, EIMS) data. All the synthesized compounds were evaluated for their toxicity potential by a brine shrimp lethality bioassay. Ten compounds i.e., 3a, 3e, 3i-3l and 3n-3q proved to be active in this assay, displaying promising toxicity (LD 50 = 1.11 × 10-5 M - 1.80 × 10-4 M). Amongst these, 3k, 3n and 3o were found to be the most active ones (LD 50 = 1.11 × 10-5 M - 1.43 × 10-5 M). Compound 3k showed the highest activity with a LD50 value of 1.11 × 10-5 M and can, therefore, be used as a lead for further studies. Structure-activity relationship (SAR) studies revealed that the presence of strong inductively electron-attracting trifluoromethoxy substituent at position-5 of the isatin moiety played an important role in inducing or enhancing toxic potentiality of some of the synthesized compounds.


PubMed | FC College, Bahauddin Zakariya University and University of Karachi
Type: Journal Article | Journal: Molecules (Basel, Switzerland) | Year: 2014

A series of twenty one N4-aryl substituted 5-trifluoromethoxyisatin-3-thiosemicarbazones 3a-3u was synthesized by the reaction of trifluoromethoxyisatin 1 with different arylthiosemicarbazides 2 in aqueous ethanol (50%), containing a few drops of acetic acid. Their structures were established on the basis of analytical (CHN) and spectral (IR, 1H-NMR, EIMS) data. All the synthesized compounds were evaluated for their toxicity potential by a brine shrimp lethality bioassay. Ten compounds i.e., 3a, 3e, 3i-3l and 3n-3q proved to be active in this assay, displaying promising toxicity (LD50 = 1.11 10-5 M - 1.80 10-4 M). Amongst these, 3k, 3n and 3o were found to be the most active ones (LD50 = 1.11 10-5 M - 1.43 10-5 M). Compound 3k showed the highest activity with a LD50 value of 1.11 10-5 M and can, therefore, be used as a lead for further studies. Structure-activity relationship (SAR) studies revealed that the presence of strong inductively electron-attracting trifluoromethoxy substituent at position-5 of the isatin moiety played an important role in inducing or enhancing toxic potentiality of some of the synthesized compounds.


Limami Y.,CNRS Chemistry of Natural Substances Laboratory | Pinon A.,CNRS Chemistry of Natural Substances Laboratory | Riaz A.,FC College | Simon A.,CNRS Chemistry of Natural Substances Laboratory
Cellular and Molecular Biology | Year: 2015

Targeting cancer cells is one of the challenges of current treatment strategies. TRAIL represents a promising therapeutic approach and over the past decades there was an increased interest in targeting TRAIL signaling to treat cancer. Indeed, TRAIL can specifically target cancer cells and exhibits very low cytotoxicity towards normal cells. However, rapidly accumulating experimental evidence has started to shed light on multiple factors which induce resistance against TRAIL in cancer cells. This resistance consists of various mechanisms including downregulation of death receptors and caspase-8 and overexpression of decoy receptors as well as antiapoptotic factors such as members of Bcl-2 family. Even if several studies focused on elucidating those resistance mechanisms, there still remain gray areas that need to be fully elucidated. Thus, therapeutic approaches could consist of targeting both resistance signaling pathways and TRAIL signaling to enhance TRAIL therapy efficiency. © 2015.


Ashraf N.,University of Central Florida | Shen Y.,University of Central Florida | Shen Y.,AMD Inc | Cao X.,University of Central Florida | And 3 more authors.
Computer Vision and Image Understanding | Year: 2013

In this paper, we fully investigate the concept of fundamental ratios, demonstrate their application and significance in view-invariant action recognition, and explore the importance of different body parts in action recognition. A moving plane observed by a fixed camera induces a fundamental matrix F between two frames, where the ratios among the elements in the upper left 2 × 2 submatrix are herein referred to as the fundamental ratios. We show that fundamental ratios are invariant to camera internal parameters and orientation, and hence can be used to identify similar motions of line segments from varying viewpoints. By representing the human body as a set of points, we decompose a body posture into a set of line segments. The similarity between two actions is therefore measured by the motion of line segments and hence by their associated fundamental ratios. We further investigate to what extent a body part plays a role in recognition of different actions and propose a generic method of assigning weights to different body points. Experiments are performed on three categories of data: the controlled CMU MoCap dataset, the partially controlled IXMAS data, and the more challenging uncontrolled UCF-CIL dataset collected on the internet. Extensive experiments are reported on testing (i) view-invariance, (ii) robustness to noisy localization of body points, (iii) effect of assigning different weights to different body points, (iv) effect of partial occlusion on recognition accuracy, and (v) determining how soon our method recognizes an action correctly from the starting point of the query video. © 2013 Elsevier Ltd. All rights reserved.


Aslam M.,College of Economy and Administration | Mughal A.R.,P.A. College | Ahmad M.,College of Economy and Administration | Yab Z.,FC College
Journal of Testing and Evaluation | Year: 2010

In this paper, we propose a group acceptance sampling plan (GASP) for truncated life tests when the lifetimes of items follow the Pareto distribution of the second kind. The minimal group size, the operating characteristic value, and the minimal ratio of the true mean life to the specified mean life regarding the proposed GASPs are found, and some of them are tabulated. An example is given for illustration. Copyright © 2010 by ASTM International.

Loading FC College collaborators
Loading FC College collaborators