Ahmad N

References (11)

Title : Cholinesterase activity as a potential biomarker for neurotoxicity induced by pesticides in vivo exposed Oreochromis niloticus (Nile tilapia) - Amin_2021_Environ.Technol__1
Author(s) : Amin M , Yousuf M , Attaullah M , Ahmad N , Azra MN , Latif M , Buneri ID , Zekker I , Batiha GE , Aboelenin SM , Zahoor M , Ikram M , Naeem M
Ref : Environ Technol , :1 , 2021
Abstract : Organophosphates (OPs) and synthetic pyrethroids (SPs) are the most popular broad spectrum pesticides, used in agriculture as they have a strong pesticidal activity while also being biodegradable in the environment. The present study aimed to demonstrate the effects of these pesticides on the Acetylcholinesterase (AChE) activity in brain, gills and body muscles of Oreochromis niloticus- an important enzyme for the assessment and biomonitoring pollution caused by neurotoxins in the environment. The fish were exposed for 24 and 48h to the LC(0) concentrations of the malathion (1.425mg/L), the chlorpyrifos (0.125mg/L) and the lambda-cyhalothrin (0.0039mg/L), respectively. The activity of the AChE was significantly increased (p < 0.05) at 24hours and decreased at 48hours (except for the chlorpyrifos- treated brain and gills while tissues had shown no activity at 48 hours' exposure) in all pesticides- treated tissues. The maximum increase in the activity and inhibition in the AChE activity were recorded as +92% and -52% in the chlorpyrifos and the lambda -cyhalothrin exposed brain tissues, respectively. Thus, the alterations in the AChE activities indicated that the applied pesticides are highly neurotoxic to fish and the enzyme (AChE) could be used as a useful biomarker for estimation of water pollution.
ESTHER : Amin_2021_Environ.Technol__1
PubMedSearch : Amin_2021_Environ.Technol__1
PubMedID: 34962184

Title : Insecticide resistance of Dengue vectors in South East Asia: a systematic review - Hassan_2021_Afr.Health.Sci_21_1124
Author(s) : Hassan MR , Azit NA , Fadzil SM , Ghani SRA , Ahmad N , Nawi AM
Ref : Afr Health Sci , 21 :1124 , 2021
Abstract : BACKGROUND: The insecticides used widely has led to resistance in the vector and impose a challenge to vector control operation. OBJECTIVES: This review aims to analyse the distribution of insecticide resistance of dengue vectors in South East Asia and to describe the mechanism of insecticide resistance. METHODS: Literature search for articles published on 2015 to 2019 from PubMed, Scopus and ProQuest was performed. Total of 37 studies included in the final review from the initial 420 studies. RESULTS: Pyrethroid resistance was concentrated on the west coast of Peninsular Malaysia and Northern Thailand and scattered at Java Island, Indonesia while organophosphate resistance was seen across the Java Island (Indonesia), West Sumatera and North Peninsular Malaysia. Organochlorine resistance was seen in Sabah, Malaysia and scattered distribution in Nusa Tenggara, Indonesia. V1016G, S989P, F1269C gene mutation in Aedes Aegypti were associated with Pyrethroid resistance in Singapore and Indonesia. In Malaysia, over-expressed with monooxygenase P450 genes (CYP9J27, CYP6CB1, CYP9J26 and CYP9M4) Glutathione S-transferases, carboxylesterases commonly associated with pyrethroids resistance in Aedes Aegypti and CYP612 overexpressed in Aedes Albopictus. The genetic mutation in A302S in Aedes Albopictus was associated with organochlorine resistance in Malaysia. CONCLUSIONS: Rotation of insecticide, integration with synergist and routine assessment of resistance profile are recommended strategies in insecticide resistance management.
ESTHER : Hassan_2021_Afr.Health.Sci_21_1124
PubMedSearch : Hassan_2021_Afr.Health.Sci_21_1124
PubMedID: 35222575

Title : Isolation, Characterization, and Medicinal Potential of Polysaccharides of Morchella esculenta - Badshah_2021_Molecules_26_
Author(s) : Badshah SL , Riaz A , Muhammad A , Tel Cayan G , Cayan F , Emin Duru M , Ahmad N , Emwas AH , Jaremko M
Ref : Molecules , 26 : , 2021
Abstract : Mushroom polysaccharides are active medicinal compounds that possess immune-modulatory and anticancer properties. Currently, the mushroom polysaccharides krestin, lentinan, and polysaccharopeptides are used as anticancer drugs. They are an unexplored source of natural products with huge potential in both the medicinal and nutraceutical industries. The northern parts of Pakistan have a rich biodiversity of mushrooms that grow during different seasons of the year. Here we selected an edible Morchella esculenta (true morels) of the Ascomycota group for polysaccharide isolation and characterization. Polysaccharopeptides and polysaccharides from this mushroom were isolated using the green chemistry, hot water treatment method. Fourier transform infrared spectroscopy revealed the sugar nature and possible beta-glucan type structure of these polysaccharides. Antioxidant assays showed that the deproteinized polysaccharides have moderate free radical scavenging activity. These isolated polysaccharides exhibited good acetylcholinesterase (AChE) and butyryl cholinesterase (BChE) inhibition activities. Therefore, these polysaccharides may be valuable for the treatment of Alzheimer's and Parkinson's diseases. Further bioassays are needed to discover the true potential of M. esculenta polysaccharides for medicinal purposes.
ESTHER : Badshah_2021_Molecules_26_
PubMedSearch : Badshah_2021_Molecules_26_
PubMedID: 33800212

Title : Attenuation of Spatial Memory in 5xFAD Mice by Halting Cholinesterases, Oxidative Stress and Neuroinflammation Using a Cyclopentanone Derivative - Ullah_2020_Pharmaceuticals.(Basel)_13_
Author(s) : Ullah R , Ali G , Ahmad N , Akram M , Kumari G , Amin MU , Umar MN
Ref : Pharmaceuticals (Basel) , 13 : , 2020
Abstract : Alzheimer's disease (AD) is an irreversible and chronic neurological disorder that gradually destroys memory and thinking skills. The research study was designed to investigate the underlying molecular signaling involved in the neuroprotective effects of cyclopentanone derivative i.e., 2-(hydroxyl-(3-nitrophenyl)methyl)cyclopentanone (3NCP) as a therapeutic agent for AD. In this study, In vivo studies were carried out on a well-known 5xFAD mice model using different behavioural test models such as open field, rotarod, Morris water maze (MWM), and Y-maze tests. Furthermore, in vitro cholinesterase inhibition activity assays were carried out. The frontal cortex (FC) and hippocampus (HC) homogenates were tested for the levels/activities of cholinesterases, glutathione (GSH), glutathione S-transferase (GST), and catalase. Furthermore, the hippocampal expression of inflammatory cytokines was observed via RT-PCR and western blot. The results of in vivo studies show an enhancement in the learning behavior. The 3NCP treatment reduced latency time in MWM and Y-maze tests, also increase spontaneous alternation indicate significant effect of 3NCP on memory. Furthermore, open field and rotarod studies revealed that 3NCP does not cause motor coordination deficit. The results of the in vitro studies revealed that the IC(50) values of the 3NCP against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) were 16.17 and 20.51 microg/mL, respectively. This decline in AChE and BChE was further supported by ex vivo studies. Further, the 3NCP mitigates the GSH level, GST, and catalase activities in HC and FC. The mRNA and protein expression of inflammatory cytokines (IL-1beta, IL-6, TNF-alpha) markedly declined in RT-PCR and western blotting. The results of the current study conclusively demonstrate that 3NCP reduces oxidative stress and mitigates neuroinflammation in 5xFAD mice, implying that 3NCP may be a potential therapeutic candidate for AD treatment in the future.
ESTHER : Ullah_2020_Pharmaceuticals.(Basel)_13_
PubMedSearch : Ullah_2020_Pharmaceuticals.(Basel)_13_
PubMedID: 33086500

Title : Silver nanoparticles from leaf extract of Mentha piperita: Eco-friendly synthesis and effect on acetylcholinesterase activity - Khatoon_2018_Life.Sci_209_430
Author(s) : Khatoon A , Khan F , Ahmad N , Shaikh S , Rizvi SMD , Shakil S , Al-Qahtani MH , Abuzenadah AM , Tabrez S , Ahmed ABF , Alafnan A , Islam H , Iqbal D , Dutta R
Ref : Life Sciences , 209 :430 , 2018
Abstract : Silver nanoparticles (AgNPs) have been used in various medicinal and commercial products because of their exceptional anti-microbial and anti-odor properties. On the other hand, increased commercialization of AgNPs containing products has led to its release into the environment. Thus, studies are needed to assess their impact on the environment as well as on human body. Several reports have shown that AgNPs could cause some serious neurotoxic effects. Most of these studies have been performed using chemically synthesized AgNPs. In contrast, green nanoparticles are usually considered safer than their chemically synthesized counterparts. Accordingly, in this research work, we have assessed the effect of AgNPs synthesized from aqueous-leaf-extract of Mentha piperita on one of the most important neurological enzymes i.e. acetylcholinesterase (AChE) to predict its neurotoxicity. M. piperita synthesized AgNPs were subjected to characterization by UV-visible-spectrometry, Scanning Electron-Microscopy as well as Transmission Electron-Microscopy. Here, the size of the AgNPs was found to be 35nm with spherical shape. These AgNPs showed concentration-dependent inhibitory-effect on the AChE enzyme-activity displaying an IC50 of 150nM. Further, kinetic analysis showed mixed type of inhibition, which means that AgNPs were capable of binding to both the free enzyme (AChE) and to the enzyme-substrate (AChE-acetylcholine) complex. These results suggest that even green synthesized AgNPs might cause neurotoxicity via inhibiting AChE activity. However, more studies are needed to elucidate the exact mechanism of neurotoxicity by AgNPs. Nevertheless, we could safely state that the present study provides relevant preliminary information regarding neurotoxicity of green synthesized AgNPs.
ESTHER : Khatoon_2018_Life.Sci_209_430
PubMedSearch : Khatoon_2018_Life.Sci_209_430
PubMedID: 30138593

Title : Anti-Alzheimer's Studies on beta-Sitosterol Isolated from Polygonum hydropiper L - Ayaz_2017_Front.Pharmacol_8_697
Author(s) : Ayaz M , Junaid M , Ullah F , Subhan F , Sadiq A , Ali G , Ovais M , Shahid M , Ahmad A , Wadood A , El-Shazly M , Ahmad N , Ahmad S
Ref : Front Pharmacol , 8 :697 , 2017
Abstract : The family Polygonaceae is known for its traditional use in the management of various neurological disorders including Alzheimer's disease (AD). In search of new anti-AD drugs, beta-sitosterol isolated from Polygonum hydropiper was subjected to in vitro, in vivo, behavioral and molecular docking studies to confirm its possibility as a potential anti-Alzheimer's agent. The in vitro AChE, BChE inhibitory potentials of beta-sitosterol were investigated following Ellman's assay. The antioxidant activity was tested using DPPH, ABTS and H2O2 assays. Behavioral studies were performed on a sub-strain of transgenic mice using shallow water maze (SWM), Y-maze and balance beam tests. beta-sitosterol was tested for in vivo inhibitory potentials against cholinesterase's and free radicals in the frontal cortex (FC) and hippocampus (HC). The molecular docking study was performed to predict the binding mode of beta-sitosterol in the active sites of AChE and BChE as inhibitor. Considerable in vitro and in vivo cholinesterase inhibitory effects were observed in the beta-sitosterol treated groups. beta-sitosterol exhibited an IC50 value of 55 and 50 mug/ml against AChE and BChE respectively. Whereas, the activity of these enzymes were significantly low in FC and HC homogenates of transgenic animals. Molecular docking studies also support the binding of beta-sitosterol with the target enzyme and further support the in vitro and in vivo results. In the antioxidant assays, the IC50 values were observed as 140, 120, and 280 mug/ml in the DPPH, ABTS and H2O2 assays respectively. The free radicals load in the brain tissues was significantly declined in the beta-sitosterol treated animals as compared to the transgenic-saline treated groups. In the memory assessment and coordination tasks including SWM, Y-maze and balance beam tests, beta-sitosterol treated transgenic animals showed gradual improvement in working memory, spontaneous alternation behavior and motor coordination. These results conclude that beta-sitosterol is a potential compound for the management of memory deficit disorders like AD.
ESTHER : Ayaz_2017_Front.Pharmacol_8_697
PubMedSearch : Ayaz_2017_Front.Pharmacol_8_697
PubMedID: 29056913

Title : Isolation of cold-active, acidic endocellulase from Ladakh soil by functional metagenomics - Bhat_2013_Extremophiles_17_229
Author(s) : Bhat A , Riyaz-Ul-Hassan S , Ahmad N , Srivastava N , Johri S
Ref : Extremophiles , 17 :229 , 2013
Abstract : Mining of soil sample from cold desert of Ladakh by functional metagenomics led to the isolation of cold-adapted endocellulase (CEL8M) that hydrolyses carboxymethyl cellulose (CMC). Mature CEL8M, a 347-residue polypeptide with a molecular mass of 38.9 kDa showed similarity to beta-1,3-1,4 D-glucanase from Klebsiella sp. The enzyme contains the catalytic module of glycosyl hydrolase family 8 but does not possess a carbohydrate-binding domain. 3D structural model of the enzyme built by homology modeling showed an architecture of (alpha/alpha)6-barrel fold. The purified enzyme was found to be active against CMC, xylan, colloidal chitosan and lichenan but not active against avicel. Glucose was not among the initial hydrolysis products, indicating an endo mode of action. CEL8M displayed maximal activity at pH 4.5 and remained significantly active (~28 %) when the temperature decreased to 10 degrees C. Cold-active endocellulase CEL8M may find applications in textile industry at low temperature which can result in energy savings.
ESTHER : Bhat_2013_Extremophiles_17_229
PubMedSearch : Bhat_2013_Extremophiles_17_229
PubMedID: 23354361

Title : The clinical significance of early proteinuria after renal transplantation - Cherukuri_2010_Transplantation_89_200
Author(s) : Cherukuri A , Welberry-Smith MP , Tattersall JE , Ahmad N , Newstead CG , Lewington AJ , Baker RJ
Ref : Transplantation , 89 :200 , 2010
Abstract : BACKGROUND: Late-onset proteinuria after renal transplantation has been universally associated with poor allograft outcomes. However, the significance of early low-grade posttransplant proteinuria remains uncertain.
METHODS: We analyzed the effect of proteinuria 3 months posttransplantation on death-censored graft loss, death with a functioning graft, vascular events within the graft's life, and estimated glomerular filtration rate at 5 years. Four hundred seventy-seven renal transplants from a single center (1988-2003) with a mean follow-up of 122 months were divided into four groups based on the median protein creatinine ratio (PCR) during the 3rd posttransplant month (PCR<0.15 [group 1, n=85]; PCR 0.15-0.5 [group 2, n=245]; PCR 0.5-1.00 [group 3, n=96]; PCR>1.00 [group 4, n=51]). Cox proportional hazards analysis was performed to study the impact of proteinuria on the various outcomes.
RESULTS: Multivariate analysis revealed that even low-level proteinuria at 3 months predicted death-censored graft failure (group 1 [reference]--hazard ratio [HR]=1, group 2--HR=7.1, group 3--HR = 10.5, group 4--HR 16.0; P=0.001). The impact on death and the occurrence of vascular events was only significant for group 4 (HR: 2.6; P=0.01 for death and HR: 2.2; P=0.04 for vascular events). Estimated glomerular filtration rate at 5 years was group 1, 48.5 mL/min; group 2, 41.2 mL/min; group 3, 31.1 mL/min; and group 4, 24.5 mL/min (P<0.001). Continued observation of group 2 to 1 year revealed adverse outcomes with increasing proteinuria.
CONCLUSIONS: Low-grade proteinuria at 3 months is associated with adverse clinical outcomes and identifies high-risk group of patients who may benefit from further intervention.
ESTHER : Cherukuri_2010_Transplantation_89_200
PubMedSearch : Cherukuri_2010_Transplantation_89_200
PubMedID: 20098283

Title : Determination of organochlorine and organophosphate pesticide residues in fruits, vegetables and sediments - Ahmad_1999_J.Environ.Sci.Health.B_34_829
Author(s) : Ahmad N , Bugueno G , Guo L , Marolt R
Ref : J Environ Sci Health B , 34 :829 , 1999
Abstract : A method is described for the determination of organochlorine and organophosphate pesticide residues in fruits, vegetables and sediments. The concentrated solvent extract was sealed in a polymeric membrane tube, dialysed in cyclohexane and the solvent replaced with hexane. The organophosphates were analysed on a specific thermionic detector without further clean-up. For the organochlorine pesticides the extract was eluted through 3 g of alumina and analysed on GC/ECD. The clean-up for sediment extract was carried out on a 10 g alumina column with 100 mL hexane containing 5% acetone and the eluate was concentrated to 5 mL. The detection limit for organophosphates on a 40 g sample and a final volume of 10 mL was on the average 0.01 mg/kg. The detection limit for organochlorine pesticides, with the final volume of 25 mL, was 0.005 mg/kg for all pesticides except for p,p'-DDT and endosulfan sulphate, which was 0.01 mg/kg. The detection limit for organochlorine pesticides in sediment, with the final volume of 2 mL, was less than 1 microgram/kg and for organophosphate pesticides less than 10 micrograms/kg when the final volume was made to 0.5 mL. At the detection limits the method produced a very high coefficient of variation for both organochlorine and organophosphate pesticides.
ESTHER : Ahmad_1999_J.Environ.Sci.Health.B_34_829
PubMedSearch : Ahmad_1999_J.Environ.Sci.Health.B_34_829
PubMedID: 10466104

Title : Passive diffusion through polymeric membranes: a novel cleanup procedure for analysis of azinphos-methyl and azinphos-ethyl residues in fruits and vegetables - Ahmad_1995_J.AOAC.Int_78_1450
Author(s) : Ahmad N , Guo L , Mandarakas P , Appleby S , Bugueno G
Ref : Journal of AOAC International , 78 :1450 , 1995
Abstract : A novel procedure is described for simple removal of coextractives prior to analysis of fruits and vegetables for azinphos-methyl and azinphos-ethyl residues. The solvent extract is concentrated, placed in a polymeric membrane tube, and then dialyzed in cyclohexane. Both azinphos-methyl and azinphos-ethyl diffuse into the surrounding solvent while coextractants remain inside the membrane. The dialyzing solvent is exchanged during concentration with n-hexane and analyzed without further cleanup by gas-liquid chromatography with a specific thermionic detector. The detection limit for a 25 g grape sample with final volume of extract made to 15 mL was 0.01 mg/kg. Recoveries of both residues from grapes averaged 107% (spike levels of 0.3 to 2.0 mg/kg). From a 20 g spinach sample, recoveries averaged 82% for azinphos-methyl and 72% for azinphos-ethyl when final volume of extract was made to 5 mL (spike levels of 0.1 to 1.0 mg/kg). Recoveries from 20 types of fruits and vegetables (20 g sample spiked at 1 mg/kg for both azinphos-methyl and azinphos-ethyl) were consistently greater than 70%, except for strawberries (61-67%) and avocado (28-34%). The high lipid content of avocado may impede diffusion of azinphos-methyl and azinphos-ethyl through the polymeric membrane. A field evaluation of the procedure showed a strong correlation (r = 0.957) between azinphos-methyl residues on grapes and treatments with 2 spray formulations. The membrane cleanup procedure is a simple and cost-effective alternative to other column or liquid-liquid partitioning procedures for azinphos-methyl and azinphos-ethyl residue analysis.
ESTHER : Ahmad_1995_J.AOAC.Int_78_1450
PubMedSearch : Ahmad_1995_J.AOAC.Int_78_1450
PubMedID: 8664581

Title : A large-scale evaluation of pirimiphos-methyl 25\% WP during 1980-1981 for malaria control in Pakistan - Nasir_1982_J.Trop.Med.Hyg_85_239
Author(s) : Nasir SM , Ahmad N , Shah MA , Azam CM
Ref : J Trop Med Hyg , 85 :239 , 1982
Abstract : The emergence of strains of malaria vectors resistant to malathion in an area of Pakistan, and the continuing search for improved methods of control, necessitated the examination of alternative safe insecticides, with improved residual effects, for future use in the Malaria Control Programme in Pakistan. For these reasons, the effectiveness of pirimiphos-methyl, as Actellic 25 WP, was evaluated on a large scale in one sub-sector of Sheikhupura district of Punjab Province near Lahore. Entomological and parasitological evaluations demonstrated that 1 g of pirimiphos-methyl/m2 was as effective as 2 g/m2. Vector mosquito densities were reduced to zero, or almost so, in all areas sprayed with pirimiphos-methyl, and only began to approach vector levels in unsprayed areas after 9-10 months. No new cases of malaria were detected in those areas sprayed with pirimiphos-methyl. Blood cholinesterase determinations after the application of the pirimiphos-methyl spray confirmed the absence of any toxic effect on the spray operators, nor were there any toxic symptoms in the house occupants.
ESTHER : Nasir_1982_J.Trop.Med.Hyg_85_239
PubMedSearch : Nasir_1982_J.Trop.Med.Hyg_85_239
PubMedID: 7154146