Search Results

You are looking at 1 - 10 of 18 items for

  • Author: Muhammad Ahmed x
Clear All Modify Search
Open access

Ahmed M. Gouda, Ahmed H. Abdelazeem, Ashraf N. Abdalla and Muhammad Ahmed

Abstract

Towards optimization of the pyrrolizine-5-carboxamide scaffold, a novel series of six derivatives (4a-c and 5a-c) was prepared and evaluated for their anti-inflammatory, analgesic and anticancer activities. The (EZ)-7-cyano-6-((4-hydroxybenzylidene)amino)-N-(p-tolyl)-2,3-dihydro-1H-pyrrolizine-5-carboxamide (4b) and (EZ)-6-((4-chlorobenzylidene)-amino)-7-cyano-N-(p-tolyl)-2,3-dihydro-1H-pyrrolizine-5-carboxamide (5b) bearing the electron donating methyl group showed the highest anti-inflammatory activity while (EZ)-6-((4-chlorobenzylidene)amino)-7-cyano-N-phenyl-2,3-dihydro-1H-pyrrolizine-5-carboxamide (5a) was the most active analgesic agent. Cytotoxicity of the new compounds was evaluated against the MCF-7, A2780 and HT29 cancer cell lines using the MTT assay. Compounds 4b and 5b displayed high anticancer activity with IC 50 in the range of 0.30–0.92 μmol L−1 against the three cell lines, while compound (EZ)-N-(4-chlorophenyl)-7-cyano-6-((4-hydroxybenzylidene)-amino)-2,3-dihydro-1H-pyrrolizine-5-carboxamide (4c) was the most active against MCF-7 cells (IC 50 = 0.08 μmol L−1). Both the anti-inflammatory and anticancer activities of the new compounds were dependent on the type of substituent on the phenyl rings. Substituents with opposite electronic effects on the two phenyl rings are preferable for high cytotoxicity against the MCF-7 and A2780 cells. COX inhibition was suggested as the molecular mechanism of the anti-inflammatory activity of the new compounds while no clear relationship could be observed between COX inhibition and anticancer activity. Compound 5b, the most active against the three cell lines, induced dose-dependent early apoptosis with 0.1–0.2 % necrosis in MCF-7 cells. New compounds showed promising drug-likeness scores while the docking study revealed high binding affinity to COX-2. Taken together, this study highlighted the significant impact of the substituents on the anti-inflammatory and anticancer activity of pyrrolizine-5-carboxamides, which could help in further optimization to discover good leads for the treatment of cancer and inflammation.

Open access

Asad Gulzar, Mahmood Ahmed, Muhammad Abdul Qadir, Muhammad Imtiaz Shafiq, Sakhawat Ali, Ijaz Ahmad and Muhammad Farooq Mukhtar

Abstract

The present invention was undertaken to study and determine the effect of potassium metabisulphite (6%) and potassium sorbate (350 ppm) treatments on the nutritional quality of osmotically-dehydrated, infrared- and microwave-blanched dried mango slices (local cultivars “Chaunsa” and “Fajri”) stored for the period of 6 months under ambient conditions. The studied parameters included physical characteristics such as water activity, non-enzymatic browning, and color values, chemical parameters such as moisture, ash, fiber, acidity and content of proteins, sugars, vitamin C, total carotenoids, and sensory attributes such as appearance, flavor and texture. Vitamin C content in osmotically-dried mango slices was higher than that of IR and MW blanched dried mango slices but the content of vitamin C of both cultivars was lower than of the fresh mango samples (Chaunsa: 135 mg/100 g, Fajri: 94 mg/100 g). Significant loss was noticed in total carotenoids content of both the cultivars with passage of time because of their susceptibility to oxidative loss caused by dry heat. No growth of yeast and mold was detected in potassium sorbate-treated dried mango slices due to their preservative effect. From the point of view of the composition and sensory quality, dried mango slices of both the cultivars have excellent nutritional qualities.

Open access

Mahmood Ahmed, Muhammad Abdul Qadir, Muhammad Imtiaz Shafiq, Muhammad Muddassar, Abdul Hameed, Muhammad Nadeem Arshad and Abdullah M. Asiri

Abstract

Curcumin is a natural product with enormous biological potential. In this study, curcumin synthesis was revisited using different reaction solvents, a catalyst (n-butylamine) and a water scavenger [(n-BuO)3B], to develop the optimal procedure for its rapid acquisition. During synthesis, solvent choice was found to be an important parameter for better curcumin yield and high purity. In a typical reaction, acetyl acetone was treated with boron trioxide, followed by condensation with vanillin in the presence of tri-n-butyl borate as water scavenger and n-butylamine as catalyst at 80 °C in ethyl acetate to afford curcumin. Moreover, curcumin was also extracted from turmeric powder and spectroscopic properties such as IR, MS, 1H NMR and 13C NMR with synthetic curcumin were established to identify any impurity. The purity of synthetic and extracted curcumin was also checked by TLC and HPLC-DAD. To computationally assess its therapeutic potential against cyclin dependent kinases (CDKs), curcumin was docked in different isoforms of CDKs. It was observed that it did not dock at the active sites of CDK2 and CDK6. However, it could enter into weak interactions with CDK4 protein.

Open access

Nisar Ahmed, Azeem Nabi, Jawad Nisar, Muhammad Tariq, Muhammad Arshad Javid and M. H. Nasim

Abstract

The electronic structure and magnetic properties of Mn doped zinc blende cadmium sulfide Cd1-xMnxS (x = 6.25 %) have been studied using spin-polarized density functional theory within the framework of Generalized Gradient Approximation (GGA), its further corrections including Hubbard U interactions (GGA + U) and a model for exchange and correlation potential Tran Blaha modified Becke-Johnson (TB-mBJ). Ferromagnetic interactions have been observed between Mn atoms via S atom due to strong p-d hybridization. The magnetic moments on Mn and its neighboring atoms have also been studied in detail using different charge analysis techniques. It has been observed that p-d hybridization reduced the value of local magnetic moment of Mn in comparison to its free space charge value and produced small local magnetic moments on the nonmagnetic S and Cd host sites. The magnetocrystalline anisotropy in [1 0 0] and [1 1 1] directions as well as exchange splitting parameters Noα and Noβ have been analyzed to confirm that ferromagnetism exists. We conclude that the ferromagnetic phase in Mn-doped CdS is not stable in “near” configuration but it is stable for “far” configuration. Mn doped CdS is a p-type semiconductor and the d-states at the top of the valence band edge give a very useful material for photoluminescence and magneto-optical devices.

Open access

Ahmed Abdul Malik, Muhammad Khairi Bin Mahyuddin, Najib Sheikh Abdisamad and Mikail Ibrahim

Abstract

Conflict is an inevitable part of human life. In any situation involving more than one person, conflict can arise. The causes of conflict range from philosophical differences and divergent goals, to power imbalances. When conflict arises, it is easy for people to be stubborn and remain entrenched in their positions and for tempers to flare, voices to rise and body language to become defensive or aggressive. Conflict is an unexpected inconvenience. This can be proved by the Lahad Datu Sabah conflict which occurred in 2013, where armed men landed in Lahad Datu to enforce an ancestral land claim. During the conflict, 12 security police were killed and some of them were mutilated. A week-long impasse in a coastal village ended in bloodshed, as a Malaysian ground assault gave way to air strikes. The aims of this research is to analyze the issues of Lahad Datu, to examine the strategies that can be used to promote peace and stability and to introduce an Islamic model of conflict resolution. A self-constructed survey instrument was distributed to 236 residents of Lahad Datu, who voluntarily participated in the study. The results indicated that a level of awareness and a resolution of conflict effects peoples’ reaction towards a government’s response to invaders, their perceptions about the causes of the conflict and their stance during a conflict. Furthermore, the study found that gender, religion, education, occupation and marital status had no effect on the dependent variables. Finally, the findings of the research disclosed that an Islamic model of conflict resolution can be used to resolve the conflict of Lahad Datu or similar social conflicts.

Open access

Tasawar Hayat, Muhammad Waqas, Sabir Ali Shehzad and Ahmed Alsaedi

Abstract

The steady stagnation-point flow of an electrically conducting fluid due to convectively heated stretched disk in the radial direction is considered. Effects of viscous dissipation and Joule heating are present. Mathematical modelling is based upon constitutive relations of Jeffrey fluid. The governing partial differential equations are first transformed into the coupled system of ordinary differential equations and then solved for the convergent series solutions. Numerical values of skin friction coefficient and local Nusselt number are also computed and analysed.

Open access

Rao Muhammad Abid Khan, Sana Anwar and Zaid Ahmed Pirzada

Abstract

Background

Many reports from developing and developed countries have shown increased resistance against macrolides and other antibiotics among Streptococcus pyogenes or group A streptococci (GAS).

Objectives

To study the current resistance pattern of S. pyogenes in Pakistan to commonly prescribed antibiotics.

Materials and Methods

Altogether, 85 (53%) of S. pyogenes strains were isolated and collected from 160 various clinical specimens from patients in Pakistan.

Results

Among other strains, 51 (32%) group D streptococci, 15 (9%) group B streptococci, 7 (4%) group G streptococci, and 2 (1%) group C streptococci were also identified. Predominantly, S. pyogenes were isolated from throat swabs (55%), followed by pus (17%), tissues (12%), and blood or wound swabs (7%). The majority of the S. pyogenes isolates were collected during the rainy season (55%) followed by cool season (40%), while merely 5% strains were isolated during the hot season, indicating a correlation of GAS incidence with seasonal changes. The highest rate of resistance was observed against clindamycin (29%), followed by macrolides (20%), and ciprofloxacin (14%). However, all strains of GAS were sensitive to penicillin and co-amoxiclav.

Conclusions

The emergence of lincosamide and macrolide resistance among GAS is a major problem worldwide which is probably due to misuse of antibiotics, self-medication, or frequent use of these antibiotics.

Open access

Shabeer Ahmad Mian, Muhammad Muzammil, Gul Rahman and Ejaz Ahmed

Abstract

The structural, electronic, elastic and optical properties of CsYx I(1 − x)(Y = F, Cl, Br) are investigated using full potential linearized augmented plane wave (FP-LAPW) method within the generalized gradient approximation (GGA). The ground state properties such as lattice constant (ao) and bulk modulus (K) have been calculated. The mechanical properties including Poisson’s ratio (σ), Young’s modulus (E), anisotropy factor (A) and shear modulus (G) were also calculated. The results of these calculations are comparable with the reported experimental and theoretical values. The ductility of CsYx I(1 − x) was analyzed using Pugh’s rule (B/G ratio) and Cauchy’s pressure (C12−C44). Our results revealed that CsF is the most ductile among the CsYxI(1 − x)(Y = F, Cl, Br) compounds. The incremental addition of lighter halogens (Yx) slightly weakens the strength of ionic bond in CsYxI(1 − x). Moreover, the optical transitions were found to be direct for binary and ternary CsYxI(1 − x). We hope that this study will be helpful in designing binary and ternary Cs halides for optoelectronic applications.

Open access

Muhammad Sohail Afzal, Shakir Ullah, Zia Ur Rehmann Farooqi, Sadia Anjum, Talha Shafi, Tahir Ahmed, Muhammad Ashraf and Ishtiaq Qadri

Abstract

Background: Malaria is a leading cause of morbidity and mortality worldwide resulting in approximately 350 to 500 million clinical cases and up to two million deaths. In Pakistan, 1.5 million cases of malaria are reported annually. The genetic factors of both host and pathogen are related to the severity of the disease. Interleukin-10 (IL-10) is an anti-inflammatory cytokine that can play a key role in plasmodium falciparum infection. Variations in IL-10 production are genetically related to polymorphisms within the IL-10 promoter region.

Objective:We investigated the association of IL-10 gene promoter -1082 G/A, -819 C/T, and -592 C/A polymorphism with malarial susceptibility in Pakistani individuals.

Methods: Ninety malarial patients and 99 healthy control subjects were enrolled. IL-10 genotyping was performed by amplification refractory mutation system-polymerase chain reaction (ARMS-PCR). Results: There was no significant difference observed in inheritance pattern of studied single nucleotide polymorphisms. All the alleles, genotypes, and haplotypes had almost similar frequencies among diseased and healthy control groups. IL-10 -1,082 homozygous G was comparatively higher in healthy subjects but difference was not statistically significant.

Conclusion: We have found no significant association between IL-10 promoter polymorphism and plasmodium falciparum infection in Pakistan. Our result from Pakistani population confirm previous association in studies from Thailand, Gambia, Republic of Mali, Tanzania, and contradict one from Kenyan population.

Open access

Ahmed Tunio, Shamasuddin Bughio, Jam Kashif Sahito, Muhammad Ghiasuddin Shah, Mahdi Ebrahimi and Shazia Parveen Tunio

Abstract

The objective of this study was to determine the physiological effects of detomidine on Pateri goats. A total of six female Pateri goats were randomly treated with three different dose rates of Detomidine at 40 μg, 50 μg and 60 μg/kg body weights. The effects of Detomidine on respiratory and heart rate, rectal temperature and serum glucose level were investigated. Following detomidine intravenous administration in goats, it produced dose dependent effect on physiological parameters. Respiratory and heart rate decreased after intravenous administration in all goats. The heart rate decreased at 5 min with all dose rates and returned to the base line at 60 min. This change in heart rate was dose dependent and there was no significant (P>0.05) change observed with 40 μg and 50 μg/kg of Detomidine. However, there was significant difference (P<0.05) at 75 min between the 40 μg and 60 μg/kg of Detomidine in all goats. However, significant (P<0.01) increase in serum glucose level occurred with all dose rates at 30 min compared with control groups. It is concluded that Detomidine has produced no adverse effect on physiological parameters.