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Fulltext Psychological Distress among Adults in Home Confinement in the Midst of COVID-19 Outbreak

Lal A, Sanaullah A, M Saleem MK, Ahmed N, Maqsood A, Ahmed N

Eur J Dent, 2020 Dec;14(S 01):S27-S33.
PMID: 33242914 DOI: 10.1055/s-0040-1718644

OBJECTIVES: The aim of this study was to evaluate psychological distress caused by the novel coronavirus disease 2019 (COVID-19) pandemic among the adult population residing in Pakistan.
MATERIALS AND METHODS: This cross-sectional survey-based study comprised 1,000 adults residing in Pakistan. A questionnaire was formulated and circulated among adult population of Pakistan, the depression and anxiety symptoms using Patient Health Questionnaire-9 (PHQ-9) and Generalized Anxiety Disorder-7 (GAD-7) scales were assessed.
STATISTICAL ANALYSIS: Independent t-test, cross tabulation, and regression analysis were used to identify variables having impact on PHQ-9 and GAD-7 scores. A p-value of ≤ 0.05 was considered statistically significant.
RESULTS: Among 1,000 participants, 573 were males and 427 were females who completed the survey. Majority were restricted to home for more than 40 days. Considerable number of participants reported depressive (540, 54%) and anxiety (480, 48%) symptoms. Gender, age, earnings, and occupation have significant relation with psychological distress, although similar was not found with education levels.
CONCLUSION: Psychological distress, a concerning yet addressable issue was found among adults arising amid COVID-19 outbreak. Currently, physical health effects of COVID-19 are being looked, while mental health effects being under-addressed. This issue should be addressed to avoid any psychological impact in future.
Fulltext Genotypic and phenotypic profiles of Escherichia coli isolates belonging to clinical sequence type 131 (ST131), clinical non-ST131, and fecal non-ST131 lineages from India

Hussain A, Ranjan A, Nandanwar N, Babbar A, Jadhav S, Ahmed N

Antimicrob Agents Chemother, 2014 Dec;58(12):7240-9.
PMID: 25246402 DOI: 10.1128/AAC.03320-14

In view of the epidemiological success of CTX-M-15-producing lineages of Escherichia coli and particularly of sequence type 131 (ST131), it is of significant interest to explore its prevalence in countries such as India and to determine if antibiotic resistance, virulence, metabolic potential, and/or the genetic architecture of the ST131 isolates differ from those of non-ST131 isolates. A collection of 126 E. coli isolates comprising 43 ST131 E. coli, 40 non-ST131 E. coli, and 43 fecal E. coli isolates collected from a tertiary care hospital in India was analyzed. These isolates were subjected to enterobacterial repetitive intergenic consensus (ERIC)-based fingerprinting, O typing, phylogenetic grouping, antibiotic sensitivity testing, and virulence and antimicrobial resistance gene (VAG) detection. Representative isolates from this collection were also analyzed by multilocus sequence typing (MLST), conjugation, metabolic profiling, biofilm production assay, and zebra fish lethality assay. All of the 43 ST131 E. coli isolates were exclusively associated with phylogenetic group B2 (100%), while most of the clinical non-ST131 and stool non-ST131 E. coli isolates were affiliated with the B2 (38%) and A (58%) phylogenetic groups, respectively. Significantly greater proportions of ST131 isolates (58%) than non-ST131 isolates (clinical and stool E. coli isolates, 5% each) were technically identified to be extraintestinal pathogenic E. coli (ExPEC). The clinical ST131, clinical non-ST131, and stool non-ST131 E. coli isolates exhibited high rates of multidrug resistance (95%, 91%, and 91%, respectively), extended-spectrum-β-lactamase (ESBL) production (86%, 83%, and 91%, respectively), and metallo-β-lactamase (MBL) production (28%, 33%, and 0%, respectively). CTX-M-15 was strongly linked with ESBL production in ST131 isolates (93%), whereas CTX-M-15 plus TEM were present in clinical and stool non-ST131 E. coli isolates. Using MLST, we confirmed the presence of two NDM-1-positive ST131 E. coli isolates. The aggregate bioscores (metabolite utilization) for ST131, clinical non-ST131, and stool non-ST131 E. coli isolates were 53%, 52%, and 49%, respectively. The ST131 isolates were moderate biofilm producers and were more highly virulent in zebra fish than non-ST131 isolates. According to ERIC-based fingerprinting, the ST131 strains were more genetically similar, and this was subsequently followed by the genetic similarity of clinical non-ST131 and stool non-ST131 E. coli strains. In conclusion, our data provide novel insights into aspects of the fitness advantage of E. coli lineage ST131 and suggest that a number of factors are likely involved in the worldwide dissemination of and infections due to ST131 E. coli isolates.
Maslinic acid modulates secreted phospholipase A2-IIA (sPLA2-IIA)-mediated inflammatory effects in macrophage foam cells formation

Yap WH, Ooi BK, Ahmed N, Lim YM

J Biosci, 2018 Jun;43(2):277-285.
PMID: 29872016

Secretory phospholipase A2-IIA (sPLA2-IIA) is one of the key enzymes causing lipoprotein modification and vascular inflammation. Maslinic acid is a pentacyclic triterpene which has potential cardioprotective and anti-inflammatory properties. Recent research showed that maslinic acid interacts with sPLA2-IIA and inhibits sPLA2-IIA-mediated monocyte differentiation and migration. This study elucidates the potential of maslinic acid in modulating sPLA2-IIA-mediated inflammatory effects in THP-1 macrophages. We showed that maslinic acid inhibits sPLA2-IIA-mediated LDL modification and suppressed foam cell formation. Further analysis revealed that sPLA2-IIA only induced modest LDL oxidation and that inhibitory effect of maslinic acid on sPLA2-IIA-mediated foam cells formation occurred independently of its anti-oxidative properties. Interestingly, maslinic acid was also found to significantly reduce lipid accumulation observed in macrophages treated with sPLA2-IIA only. Flow cytometry analysis demonstrated that the effect observed in maslinic acid might be contributed in part by suppressing sPLA2-IIA-induced endocytic activity, thereby inhibiting LDL uptake. The study further showed that maslinic acid suppresses sPLA2-IIA-induced up-regulation of PGE2 levels while having no effects on COX-2 activity. Other pro-inflammatory mediators TNF-a and IL-6 were not induced in sPLA2-IIA-treated THP-1 macrophages. The findings of this study showed that maslinic acid inhibit inflammatory effects induced by sPLA2-IIA, including foam cells formation and PGE2 production.
Fulltext One year survivor of metastatic renal cell carcinoma treated with pazopanib

Inn FX, Ahmed N, Hing EY, Jasman MH

Urol Ann, 2017 5 10;9(2):194-196.
PMID: 28479777 DOI: 10.4103/0974-7796.204178

Tyrosine kinase inhibitor (TKI) and its side effects are well known. However, these are mainly descriptive, with pictorial data lacking. Here, in we report a case of metastatic renal cell carcinoma, treated with TKI, with classic side effects; supplemented with images that demonstrate the adverse effects of the drug. In addition, we discuss and demonstrate the computed tomography changes.
Differential effects of sPLA2-GV and GX on cellular proliferation and lipid accumulation in HT29 colon cancer cells

Yap WH, Phang SW, Ahmed N, Lim YM

Mol Cell Biochem, 2018 Oct;447(1-2):93-101.
PMID: 29374817 DOI: 10.1007/s11010-018-3295-y

Secretory phospholipase A2 (sPLA2) group of enzymes have been shown to hydrolyze phospholipids, among which sPLA2 Group V (GV) and Group X (GX) exhibit high selectivity towards phosphatidylcholine-rich cellular plasma membranes. The enzymes have recently emerged as key regulators in lipid droplets formation and it is hypothesized that sPLA2-GV and GX enhanced cell proliferation and lipid droplet accumulation in colon cancer cells (HT29). In this study, cell viability and lipid droplet accumulation were assessed by Resazurin assay and Oil-Red-O staining. Interestingly, both sPLA2-GV and GX enzymes reduced intracellular lipid droplet accumulation and did not significantly affect cell proliferation in HT29 cells. Incubation with varespladib, a pan-inhibitor of sPLA2-Group IIA/V/X, further suppressed lipid droplets accumulation in sPLA2-GV but have no effects in sPLA2-GX-treated cells. Further studies using catalytically inactive sPLA2 enzymes showed that the enzymes intrinsic catalytic activity is required for the net reduction of lipid accumulation. Meanwhile, inhibition of intracellular phospholipases (iPLA2-γ and cPLA2-α) unexpectedly enhanced lipid droplet accumulation in both sPLA2-GV and GX-treated cells. The findings suggested an interconnected relationship between extracellular and intracellular phospholipases in lipid cycling. Previous studies indicated that sPLA2 enzymes are linked to cancer development due to their ability to induce release of arachidonic acid and eicosanoids as well as the stimulation of lipid droplet formation. This study showed that the two enzymes work in a distinct manner and they neither confer proliferative advantage nor enhanced the net lipid droplet accumulation in HT29 cells.
A study to examine the ageing behaviour of cold plasma-treated agricultural seeds

Ahmed N, Siow KS, Wee MFMR, Patra A

Sci Rep, 2023 Jan 30;13(1):1675.
PMID: 36717647 DOI: 10.1038/s41598-023-28811-w

Cold plasma (low pressure) technology has been effectively used to boost the germination and growth of various crops in recent decades. The durability of these plasma-treated seeds is essential because of the need to store and distribute the seeds at different locations. However, these ageing effects are often not ascertained and reported because germination and related tests are carried out within a short time after the plasma-treatment. This research aims to fill that knowledge gap by subjecting three different types of seeds (and precursors): Bambara groundnuts (water), chilli (oxygen), and papaya (oxygen) to cold plasma-treatment. Common mechanisms found for these diverse seed types and treatment conditions were the physical and chemical changes induced by the physical etching and the cold plasma on the seeds and subsequent oxidation, which promoted germination and growth. The high glass transition temperature of the lignin-cellulose prevented any physical restructuring of the surfaces while maintaining the chemical changes to continue to promote the seeds germination and growth. These changes were monitored over 60 days of ageing using water contact angle (WCA), water uptake, electrical conductivity, field emission scanning electron microscopy (FE-SEM) and X-ray photoelectron spectroscopy (XPS). The vacuum effect was also investigated to separate its effect from cold plasma (low pressure). This finding offers a framework for determining how long agricultural seeds that have received plasma treatment can be used. Additionally, there is a need to transfer this research from the lab to the field. Once the impact of plasma treatment on seeds has been estimated, it will be simple to do so.
Identification of dual active sites in Caenorhabditis elegans GANA-1 protein: an ortholog of the human α-GAL a and α-NAGA enzymes

Cheong CSY, Khan SU, Ahmed N, Narayanan K

J Biomol Struct Dyn, 2023 Jul;41(11):5261-5276.
PMID: 35694994 DOI: 10.1080/07391102.2022.2084162

Fabry disease (FD) is caused by a defective α-galactosidase A (α-GAL A) enzyme responsible for breaking down globotriaosylceramide (Gb3). To develop affordable therapeutics, more effort is needed to obtain insights into the underlying mechanism of FD and understanding human α-GAL A structure and function in related animal models. We adopted C. elegans as a model to elucidate the sequence and 3D structure of its GANA-1 enzyme and compared it to human α-GAL A. We constructed GANA-1 3D structure by homology modelling and validated the quality of the predicted GANA-1 structure, followed by computational docking of human ligands. The GANA-1 protein shared sequence similarities up to 42.1% with the human α-GAL A in silico and had dual active sites. GANA-1 homology modelling showed that 11 out of 13 amino acids in the first active site of GANA-1 protein overlapped with the human α-GAL A active site, indicating the prospect for substrate cross-reaction. Computational molecular docking using human ligands like Gb3 (first pocket), 4-nitrophenyl-α-D-galactopyranoside (second pocket), α-galactose (second pocket), and N-acetyl-D-galactosamine (second pocket) showed negative binding energy. This revealed that the ligands were able to bind within both GANA-1 active sites, mimicking the human α-GAL A and α-NAGA enzymes. We identified human compounds with adequate docking scores, predicting robust interactions with the GANA-1 active site. Our data suggested that the C. elegans GANA-1 enzyme may possess structural and functional similarities to human α-GAL A, including an intrinsic capability to metabolize Gb3 deposits.Communicated by Ramaswamy H. Sarma.
18F-FDG PET Uptake in the Scalp After Platelet-Rich Plasma Therapy

Usmani S, Al-Turkait D, Al-Kandari F, Ahmed N

Clin Nucl Med, 2022 Jan 01;47(1):e43-e44.
PMID: 34034312 DOI: 10.1097/RLU.0000000000003707

18F-FDG PET/CT has been found useful for the detection of the source of infection/inflammation in the body. Platelet-rich plasma is a new treatment modality in which plasma is injected subdermally or intradermally for potential hair regrowth into the scalp. We report a case of 43-year-old woman with right breast cancer who underwent surgery, chemotherapy, and radiotherapy 2 years ago and is currently on hormonal therapy. 18F-FDG PET/CT demonstrate incidental findings of increased FDG avidity in the scalp after platelet-rich plasma therapy.
Fulltext In vivo anticlastogenic effect of silymarin from milk thistle Silybum marianum L

Anwar S, Madkor HR, Ahmed N, Wagih ME

Indian J Pharmacol, 2018 9 1;50(3):108-115.
PMID: 30166747 DOI: 10.4103/ijp.IJP_660_16

OBJECTIVE: Silymarin, extracted from the seeds of Silybum marianum L. (Milk thistle), is traditionally used for treating various illnesses such as diabetes, cancer, inflammation, hepatitis, liver cirrhosis, and renal problems. Acute cytotoxicity and genotoxicity studies have been reported with ambiguous outcomes; however, its relevant anticlastogenic potential is not yet evaluated. This study was aimed to evaluate in vivo subacute anticlastogenic properties of silymarin to validate its use as a medicinal agent.
MATERIALS AND METHODS: Silymarin was isolated from seeds of milk thistle. Various genotoxicity bioassays of silymarin were performed using mice. First, the bone marrow cell proliferation was estimated by calculating mitotic index. Second, the chromosomal abnormalities in mice bone marrow cells were studied. Third, micronucleated polychromatic erythrocytes (MPE) test and in vivo activation of sister chromatid exchanges (SCEs) were carried out in mice bone marrow cells. Finally, primary spermatocytes were analyzed to estimate genotoxic effect of silymarin on germ cells.
RESULTS: We found that silymarin is capable of inducing a significant increase (P ≤ 0.05) in cell proliferation of bone marrow cells. There is no increase in chromosomal aberrations following silymarin treatments. Results clearly showed that it significantly (P ≤ 0.05) decreased the MPE. Likewise, it was found to be a negative inducer of SCEs. It decreased in total abnormal metaphase, SCEs, MPE, and aberrant diakinesis.
CONCLUSION: The results demonstrated that silymarin has a strong anticlastogenic activity upon mice genome in somatic and germ cells, indicating its safe use as a medicinal substance. Furthermore, it is not only safe but also has protective effect from clastogens.
Fulltext An Approach for the Optimization of Thermal Conductivity and Viscosity of Hybrid (Graphene Nanoplatelets, GNPs: Cellulose Nanocrystal, CNC) Nanofluids Using Response Surface Methodology (RSM)

Yaw CT, Koh SP, Sandhya M, Ramasamy D, Kadirgama K, Benedict F, et al.

Nanomaterials (Basel), 2023 May 10;13(10).
PMID: 37242013 DOI: 10.3390/nano13101596

Response surface methodology (RSM) is used in this study to optimize the thermal characteristics of single graphene nanoplatelets and hybrid nanofluids utilizing the miscellaneous design model. The nanofluids comprise graphene nanoplatelets and graphene nanoplatelets/cellulose nanocrystal nanoparticles in the base fluid of ethylene glycol and water (60:40). Using response surface methodology (RSM) based on central composite design (CCD) and mini tab 20 standard statistical software, the impact of temperature, volume concentration, and type of nanofluid is used to construct an empirical mathematical formula. Analysis of variance (ANOVA) is applied to determine that the developed empirical mathematical analysis is relevant. For the purpose of developing the equations, 32 experiments are conducted for second-order polynomial to the specified outputs such as thermal conductivity and viscosity. Predicted estimates and the experimental data are found to be in reasonable arrangement. In additional words, the models could expect more than 85% of thermal conductivity and viscosity fluctuations of the nanofluid, indicating that the model is accurate. Optimal thermal conductivity and viscosity values are 0.4962 W/m-K and 2.6191 cP, respectively, from the results of the optimization plot. The critical parameters are 50 °C, 0.0254%, and the category factorial is GNP/CNC, and the relevant parameters are volume concentration, temperature, and kind of nanofluid. From the results plot, the composite is 0.8371. The validation results of the model during testing indicate the capability of predicting the optimal experimental conditions.
Fulltext Synthesis, characterization, optical properties, biological activity and theoretical studies of a 4 nitrobenzylidene) amino) phenyl)imino)methyl)naphthalen-2-ol -based fluorescent Schiff base

AlHazmy SM, Zouaghi MO, Al-Hakimi AN, Alorini T, Alhagri IA, Arfaoui Y, et al.

Heliyon, 2024 Mar 15;10(5):e26349.
PMID: 38495175 DOI: 10.1016/j.heliyon.2024.e26349

A new Schiff base, 1-(E)-(4-((E) 4nitrobenzylidene) amino) phenyl)imino) methyl)naphthalen-2-ol (4NMN), was prepared from the reaction of p-phenylenediamine with 2-hydroxy-1-naphthaldehyde and 4-nitrobenzaldehyde and characterized with spectroscopic analysis. UV-VIS and NMR. Frontier molecular orbitals, molecular electrostatic potential, and chemical reactivity descriptors of the synthesized compound were studied using molecular modeling methods. The antibacterial and antifungal activities of the Schiff base were studied for its minimum inhibitory concentration. The compound showed a higher effect on yeast than against bacteria. Density functional theory (DFT) calculations were performed to study the mechanism of reaction for the synthesis of 4NMN, and the results were consistent with the experimental findings. 4NMN exhibited moderate antibacterial and antifungal activities and demonstrated higher inhibition potential against different resistant strains compared to the reference drug gentamycin. The absorption and fluorescence spectra of 4NMN were measured in different solvents, and the effect of relative polarity and acidity on the medium was observed. An inner filter effect was observed at high concentrations, and the compound showed considerable fluorescence enhancement with increasing medium viscosity and fluorescence quenching by the addition of traces of Cr1+ and Cu2+. Additionally, molecular docking studies were conducted to investigate the efficiency of antibacterial and antifungal targets.
Fulltext Investigation of the EMG-time relationship of the biceps Brachii muscle during contractions

Ahamed NU, Ahmed N, Alqahtani M, Altwijri O, Ahmad RB, Sundaraj K

J Phys Ther Sci, 2015 Jan;27(1):39-40.
PMID: 25642033 DOI: 10.1589/jpts.27.39

[Purpose] This study investigated the changes in the slope of EMG-time curves (relationship) at the maximal and different levels of dynamic (eccentric and concentric) and static (isometric) contractions. [Subjects and Methods] The subject was a 17 year-old male adolescent. The surface EMG signal of the dominant arm's biceps brachii (BB) was recorded through electrodes placed on the muscle belly. [Results] The results obtained during the contractions show that the regression slope was very close to 1.00 during concentric contraction, whereas those of eccentric and isometric contractions were lower. Significant differences were found for the EMG amplitude and time lags among the contractions. [Conclusion] The results show that the EMG signal of the BB varies among the three modes of contraction and the relationship of the EMG amplitude with a time lag gives the best fit during concentric contraction.
Fulltext Numerical investigation of the effect of stenosis geometry on the coronary diagnostic parameters

Kamangar S, Kalimuthu G, Badruddin IA, Badarudin A, Ahmed NJ, Khan TM

ScientificWorldJournal, 2014;2014:354946.
PMID: 25258722 DOI: 10.1155/2014/354946

The present study deals with the functional severity of a coronary artery stenosis assessed by the fractional flow reserve (FFR). The effects of different geometrical shapes of lesion on the diagnostic parameters are unknown. In this study, 3D computational simulation of blood flow in three different geometrical shapes of stenosis (triangular, elliptical, and trapezium) is considered in steady and transient conditions for 70% (moderate), 80% (intermediate), and 90% (severe) area stenosis (AS). For a given percentage AS, the variation of diagnostic parameters which are derived from pressure drop across the stenosis was found in three different geometrical shapes of stenosis and it was observed that FFR is higher in triangular shape and lower in trapezium shape. The pressure drop coefficient (CDP) was higher in trapezium shape and lower in triangular model whereas the LFC shows opposite trend. From the clinical perspective, the relationship between percentage AS and FFR is linear and inversely related in all the three models. A cut-off value of 0.75 for FFR was observed at 76.5% AS in trapezium model, 79.5% in elliptical model, and 82.7% AS for the triangular shaped model. The misinterpretation of the functional severity of the stenosis is in the region of 76.5%-82.7 % AS from different shapes of stenosis models.
Extraintestinal pathogenic Escherichia coli (ExPEC) of human and avian origin belonging to sequence type complex 95 (STC95) portray indistinguishable virulence features

Nandanwar N, Janssen T, Kühl M, Ahmed N, Ewers C, Wieler LH

Int J Med Microbiol, 2014 Oct;304(7):835-42.
PMID: 25037925 DOI: 10.1016/j.ijmm.2014.06.009

Extraintestinal pathogenic Escherichia coli (ExPEC) strains of certain genetic lineages are frequently implicated in a wide range of diseases in humans and birds. ExPEC strains belonging to the phylogenetic lineage/sequence type complex 95 (STC95) are one such prominent lineage that is commonly isolated from extraintestinal infections such as systemic disease in poultry and urinary tract infections (UTIs), neonatal meningitis and sepsis in humans. Several epidemiological studies have indicated that ST95 strains obtained from such infections may share similar virulence genes and other genomic features. However, data on their ability to establish infections in vivo as deduced from the manifestation of similar virulence phenotypes remain elusive. In the present study, 116 STC95 ExPEC isolates comprising 55 human and 61 avian strains, possessing similar virulence gene patterns, were characterized in vitro using adhesion, invasion, biofilm formation and serum bactericidal assays. Overall, STC95 strains from both groups, namely human and birds, were equally capable of adhering to and invading the two mammalian kidney cell lines. Similarly, these strains were able to form strong biofilms in M63 medium. Furthermore, they were equally resistant to the bactericidal activity of human and avian serum. Our cumulative data reinforce the understanding that ST95 strains from poultry present a potential zoonotic risk and therefore need a One Health strategy for a successfull intervention.
Mycobacterium avium subsp. paratuberculosis is not discerned in diabetes mellitus patients in Hyderabad, India

Rani PS, Doddam SN, Agrawal S, Hasnain SE, Sechi LA, Kumar A, et al.

Int J Med Microbiol, 2014 Jul;304(5-6):620-5.
PMID: 24863528 DOI: 10.1016/j.ijmm.2014.04.010

Mycobacterium avium ssp. paratuberculosis (MAP) is an obligate intracellular pathogen. It causes chronic intestinal inflammation in ruminants known as Johne's disease and is associated with human Crohn's disease. Furthermore, association of MAP with other autoimmune diseases, such as type-1 diabetes, has been established in patients from Sardinia (Italy) which is a MAP endemic and genetically isolated region. Due to largest livestock population and consequently high MAP prevalence amidst a very high diabetes incidence in India, we sought to test this association on a limited number of patient samples from Hyderabad. Our results of ELISA with MAP lysate and MAP-specific protein MAP3738c as well as PCR/real-time PCR of MAP-specific sequences IS900 and/or f57 indicated that, in contrast to Sardinian diabetic patients, MAP infection in blood is not discerned in diabetic patients in Hyderabad. The association of a mycobacterial trigger with diabetes therefore could well be a population-specific phenomenon, highly dependent on genetic repertoire and the environment of susceptible populations. However, a larger study is needed in order to confirm this.
Effect of porous media of the stenosed artery wall to the coronary physiological diagnostic parameter: a computational fluid dynamic analysis

Govindaraju K, Kamangar S, Badruddin IA, Viswanathan GN, Badarudin A, Salman Ahmed NJ

Atherosclerosis, 2014 Apr;233(2):630-635.
PMID: 24549189 DOI: 10.1016/j.atherosclerosis.2014.01.043

Functional assessment of a coronary artery stenosis severity is generally assessed by fractional flow reserve (FFR), which is calculated from pressure measurements across the stenosis. The purpose of this study is to investigate the effect of porous media of the stenosed arterial wall on this diagnostic parameter. To understand the role of porous media on the diagnostic parameter FFR, a 3D computational simulations of the blood flow in rigid and porous stenotic artery wall models are carried out under steady state and transient conditions for three different percentage area stenoses (AS) corresponding to 70% (moderate), 80% (intermediate), and 90% (severe). Blood was modeled as a non Newtonian fluid. The variations of pressure drop across the stenosis and diagnostic parameter were studied in both models. The FFR decreased in proportion to the increase in the severity of the stenosis. The relationship between the percentage AS and the FFR was non linear and inversely related in both the models. The cut-off value of 0.75 for FFR was observed at 81.89% AS for the rigid artery model whereas 83.61% AS for the porous artery wall model. This study demonstrates that the porous media consideration on the stenotic arterial wall plays a substantial role in defining the cut-off value of FFR. We conclude that the effect of porous media on FFR, could lead to misinterpretation of the functional severity of the stenosis in the region of 81.89 %-83.61% AS.
The influence of artery wall curvature on the anatomical assessment of stenosis severity derived from fractional flow reserve: a computational fluid dynamics study

Govindaraju K, Viswanathan GN, Badruddin IA, Kamangar S, Salman Ahmed NJ, Al-Rashed AA

Comput Methods Biomech Biomed Engin, 2016 Nov;19(14):1541-9.
PMID: 27052093 DOI: 10.1080/10255842.2016.1170119

This study aims to investigate the influence of artery wall curvature on the anatomical assessment of stenosis severity and to identify a region of misinterpretation in the assessment of per cent area stenosis (AS) for functionally significant stenosis using fractional flow reserve (FFR) as standard. Five artery models of different per cent AS severity (70, 75, 80, 85 and 90%) were considered. For each per cent AS severity, the angle of curvature of the arterial wall varied from straight to an increasingly curved model (0°, 30°, 60°, 90° and 120°). Computational fluid dynamics was performed under transient physiologic hyperemic flow conditions to investigate the influence of artery wall curvature on the pressure drop and the FFR. The findings in this study may be useful in in vitro anatomical assessment of functionally significant stenosis. The FFR decreased with increasing stenosis severity for a given curvature of the artery wall. Moreover, a significant decrease in FFR was found between straight and curved models discussed for a given severity condition. These findings indicate that the curvature effect was included in the FFR assessment in contrast to minimum lumen area (MLA) or per cent AS assessment. The MLA or per cent AS assessment may lead to underestimation of stenosis severity. From this numerical study, an uncertainty region could be evaluated using the clinical FFR cutoff value of 0.8. This value was observed at 81.98 and 79.10% AS for arteries with curvature angles of 0° and 120° respectively. In conclusion, the curvature of the artery should not be neglected in in vitro anatomical assessment.
Fulltext Cytotoxic and apoptotic effects of heat killed Mycobacterium indicus pranii (MIP) on various human cancer cell lines

Subramaniam M, In LL, Kumar A, Ahmed N, Nagoor NH

Sci Rep, 2016;6:19833.
PMID: 26817684 DOI: 10.1038/srep19833

Mycobacterium indicus pranii (MIP) is a non-pathogenic mycobacterium, which has been tested on several cancer types like lung and bladder where tumour regression and complete recovery was observed. In discovering the potential cytotoxic elements, a preliminary test was carried out using four different fractions consisting of live bacteria, culture supernatant, heat killed bacteria and heat killed culture supernatant of MIP against two human cancer cells A549 and CaSki by 3-(4,5-dimethyl thiazol)-2,5-diphenyl tetrazolium bromide (MTT) assay. Apoptosis was investigated in MCF-7 and ORL-115 cancer cells by poly-(ADP-ribose) polymerase (PARP) and DNA fragmentation assays. Among four MIP fractions, only heat killed MIP fraction (HKB) showed significant cytotoxicity in various cancer cells with inhibitory concentration, IC50 in the range 5.6-35.0 μl/(1.0 × 10(6) MIP cells/ml), while cytotoxicity effects were not observed in the remaining fractions. HKB did not show cytotoxic effects on non-cancerous cells contrary to cancerous cells, suggesting its safe usage and ability to differentially recognize between these cells. Evaluation on PARP assay further suggested that cytotoxicity in cancer cells were potentially induced via caspase-mediated apoptosis. The cytotoxic and apoptotic effects of MIP HKB have indicated that this fraction can be a good candidate to further identify effective anti-cancer agents.
Intravesical stent position as a predictor of quality of life in patients with indwelling ureteral stent

Inn FX, Ahmed N, Hou LG, Abidin ZAZ, Yi LL, Zainuddin ZM

Int Urol Nephrol, 2019 Nov;51(11):1949-1953.
PMID: 31441009 DOI: 10.1007/s11255-019-02262-7

PURPOSE: The internal drainage provided by a ureteral stent helps with the relief and prevention of ureteral obstruction. By definition, correct stent placement is one with a complete loop in both the renal pelvis and bladder. This prevents stent migration proximally or distally despite urinary flow, patient movement, and ureteral peristalsis.
METHODS: We performed a comparative prospective cross-sectional study assessing the impact of intravesical stent position on the quality of life in 46 patients with a ureteral stent. This is done using the Ureteral Stent Symptom Questionnaire (USSQ).
RESULTS: 52.5% of patients had an ipsilateral positioned intravesical stent, while the remaining had their stent positioned contralaterally. Intravesical stent position significantly influenced the quality of life. The USSQ score was worse for the contralateral group. Subscore analysis found that urinary symptoms and body pain index contribute significantly to the morbidity. Majority of patients in the ipsilateral group reported no discomfort as compared to the contralateral group.
CONCLUSIONS: To the best of our knowledge, this is the first study assessing the impact of intravesical stent position on the quality of life in the Asian population. Intravesical stent position has a significant influence on patient's morbidity and quality of life in particular towards their urinary irritative symptoms and body pain. It is imperative to ensure correct distal placement of ureteric stent that does not cross the midline to the contralateral site. We believe that the USSQ should be used in daily clinical practice in assessing the symptoms related to indwelling ureteric stents.
Indole alkaloids and anti-nociceptive mechanisms of Tabernaemontana divaricata (L.) R. Br. flower methanolic extract

Ali Khan MS, Misbah, Ahmed N, Arifuddin M, Rehman A, Ling MP

Food Chem Toxicol, 2018 Jun 05.
PMID: 29883785 DOI: 10.1016/j.fct.2018.06.007

Flowers of Tabernaemontana divaricata (L.) R. Br., (Apocynaceae) are used in traditional medicine for analgesic property. The present study was performed to isolate the active principles and investigate the mechanisms involved in the anti-nociception caused by T. divaricata flower methanolic extract (TDFME). The extract in the doses of 125, 250 and 500 mg/kg, p.o was subjected to various assays in acetic acid induced abdominal writhing and formalin induced paw licking test models. Naloxone, L-Arginine, Glibenclamide and Glutamate were used as inducers while Morphine, L-NAME, Methylene blue and Aspirin served as standard drugs. The phytochemical analysis led to the isolation of three indole alkaloids namely Voacangine, Catharanthine and O-acetyl Vallesamine. The anti-nociception produced by TDFME was attenuated significantly (p< 0.001) by the intra-peritoneal pretreatment of naloxone, L-Arginine and glibenclamide. The nociception produced by glutamate was inhibited by TDFME. TDFME also enhanced the antinociceptive activity of L-NAME when given in combination. However TDFME co-administration did not produce significant results with methylene blue indicating lack of cGMP involvement. These results indicate that TDFME produces anti-nociception action mediated by opioid, nitric oxide, K+-ATP and glutamate mechanisms and the effect is largely related to the indole alkaloids.

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