Biochemistry Commons^™

Acanthamoeba Castellanii Of The T4 Genotype Is A Potential Environmental Host For Enterobacter Aerogenes And Aeromonas Hydrophila, Farzana Abubakar Yousuf, Ruqaiyyah Siddiqui, Naveed Ahmed Khan

Department of Biological & Biomedical Sciences

Background: Acanthamoeba can interact with a wide range of microorganisms such as viruses, algae, yeasts, protists and bacteria including Legionella pneumophila, Pseudomonas aeruginosa, Vibrio cholerae, Helicobacter pylori, Listeria monocytogenes, Mycobacterium spp., and Escherichia coli. In this capacity, Acanthamoeba has been suggested as a vector in the transmission of bacterial pathogens to the susceptible hosts.
Methods: Here, we used a keratitis isolate of A. castellanii of the T4 genotype and studied its interactions with two bacterial genera which have not been tested before, Enterobacter aerogenes, and Aeromonas hydrophila, as well as E. coli. Assays were performed to determine bacterial association with …

Epidemiological Ins And Outs Of Helicobacter Pylori: A Review, Jibran Sualeh Muhammad, Syed Faisal Zaidi, Toshiro Sugiyama

Department of Biological & Biomedical Sciences

Helicobacter pylori infection is now recognised as a worldwide problem. It is the most common cause of chronic gastritis, and is strongly linked to peptic ulcer disease and gastric cancer. A comprehensive understanding of epidemiological ins and outs of H. pylori infection is very important in solving the patho-physiological enigma and might help in leading towards better management and prognosis of infection. This article presents a review of the literature on the epidemiology of H. pylori infection from 2006 to 2011. The authors used Medical Subject Heading (MeSH) terms 'Helicobacter' with 'epidemiology,' 'transmission' or 'risk factor' to search PubMed database. …

Photochemotherapeutic Strategies Against Acanthamoeba Keratitis, Ruqaiyyah Siddiqui, Naveed Ahmed Khan

Department of Biological & Biomedical Sciences

Here, we determined the potential of photochemotherapy, namely the application of photodynamic compounds followed by exposure to a suitable source of UV-visible radiation against corneal pathogen, Acanthamoeba. Organometallic macromolecule, tin porphyrin [Sn(IV)porphyrin] was synthesized and purity confirmed using nuclear magnetic resonance spectroscopy. The Sn(IV)porphyrin was tested against a keratitis isolate of Acanthamoeba castellanii belonging to the T4 genotype using growth and viability assays. The effects of Sn(IV)porphyrin on A. castellanii binding to and cytopathogenicity of human corneal epithelial cells in vitro were tested. The metalloporphyrin showed potent amoebistatic effects. The tin porphyrin inhibited amoebae binding to and cytopathogenicity of corneal …

Effects Of Betel Nut On Cardiovascular Risk Factors In A Rat Model, Mohammad Perwaiz Iqbal, Naseema Mehboobali, Ghulam Haider, Shahid Pervez, Iqbal Azam

Department of Biological & Biomedical Sciences

Background: Areca nut (commonly known as betel nut) chewing has been shown to be associated with metabolic syndrome and cardiovascular disease (CVD). The mechanism by which betel nut ingestion could lead to development of CVD is not precisely known; however, dyslipidemia, hyperhomocysteinemia, hypertriglyceridemia and inflammation could be some of the potential risk factors. This study was undertaken to investigate the effects of two dosages of betel nut on homocysteinemia, inflammation and some of the components of metabolic syndrome, such as hypertriglyceridemia, low HDL-cholesterol, obesity and fasting hyperglycemia in a rat model.
Methods: Thirty-six adult female Sprague Dawley rats, aged 10–12 …

The Role Of Src Kinase In The Biology And Pathogenesis Of Acanthamoeba Castellanii, Ruqaiyyah Siddiqui, Junaid Iqbal, Marie-Josee Maugueret, Naveed Ahmed Khan

Department of Biological & Biomedical Sciences

Background: Acanthamoeba species are the causative agents of fatal granulomatous encephalitis in humans. Haematogenous spread is thought to be a primary step, followed by blood-brain barrier penetration, in the transmission of Acanthmaoeba into the central nervous system, but the associated molecular mechanisms remain unclear. Here, we evaluated the role of Src, a non-receptor protein tyrosine kinase in the biology and pathogenesis of Acanthamoeba.
Methods: Amoebistatic and amoebicidal assays were performed by incubating amoeba in the presence of Src kinase-selective inhibitor, PP2 (4-amino-5-(4-chlorophenyl)-7-(t-butyl)pyrazolo[3,4-d]pyrimidine) and its inactive analog, PP3 (4-amino-7-phenylpyrazolo[3,4-d]pyrimidine). Using this inhibitor, the role of Src kinase in A. castellanii interactions …

Studies On Antidyslipidemic Effects Of Morinda Citrifolia (Noni) Fruit, Leaves And Root Extracts., Saf-Ur Rehman Mandukhail, Nauman Aziz, Anwar Gilani

Department of Biological & Biomedical Sciences

Background: The objective of present study was to provide the pharmacological basis for the medicinal use of Morinda citrifolia Linn in dyslipidemia using the aqueous-ethanolic extracts of its fruits (Mc.Cr.F), leaves (Mc.Cr.L) and roots (Mc.Cr.R). Results: Mc.Cr.F, Mc.Cr.L and Mc.Cr.R showed antidyslipidemic effects in both triton (WR-1339) and high fat diet-induced dyslipidemic rat models to variable extents. All three extracts caused reduction in total cholesterol and triglyceride levels in triton-induced dyslipidemia. In high fat diet-induced dyslipidemia all these extracts caused significant reduction in total cholesterol, triglyceride, low density lipoprotein-cholesterol (LDL-C), atherogenic index and TC/HDL ratio. Mc.Cr.R extract also caused increase …

Antispasmodic And Vasodilator Activities Of Morinda Citrifolia Root Extract Are Mediated Through Blockade Of Voltage Dependent Calcium Channels, Anwarul Hassan Gilani, Saf-Ur-Rehman Mandukhail, Javeid Iqbal, Masoom Yasinzai, Nauman Aziz, Aslam Khan, Najeeb-Ur-Rehman

Department of Biological & Biomedical Sciences

Background: Morinda citrifolia (Noni) is an edible plant with wide range of medicinal uses. It occurs exclusively in tropical climate zone from India through Southeast Asia and Australia to Eastern Polynesia and Hawaii. The objective of this study was to explore the possible mode(s) of action for its antispasmodic, vasodilator and cardio-suppressant effects to rationalize its medicinal use in gut and cardiovascular disorders. Methods: Isolated tissue preparations such as, rabbit jejunum, rat and rabbit aorta and guinea pig atria were used to test the antispasmodic and cardiovascular relaxant effects and the possible mode of action(s) of the 70% aqueous-ethanolic extract …

Effect Of Chronic Treatment With A Cyclooxygenase Inhibitor On Reproductive Parameters In Male Rat, Sheikh A Saeed, Naheed Anwar, Khalid M Khan, Noorjehan Sarfraz

Department of Biological & Biomedical Sciences

BACKGROUND: Indomethacin is a member of non-steroidal anti-inflammatory drugs (NSAIDs) commonly used for treatment of gout, arthritis, and other inflammatory conditions. It has been shown to inhibit ovarian prostaglandins synthesis in mammals, birds, fish and reptiles. However, the effects of its chronic administration on male reproductive functions remain largely unknown. Using rat as a model, we studied the effect of chronic treatment with indomethacin on the male reproductive system.

METHODS: Testosterone was measured in the serum, testicular tissue, and testicular interstitial fluid by radioimmunoassay. Moreover, we also studied the direct effect of indomethacin in vitro on luteinizing hormone stimulated testosterone …

Altered Expression Of Cell Cycle And Apoptotic Proteins In Chronic Hepatitis C Virus Infection., Saira Sarfraz, Saeed Hamid, Anwar Ali Siddiqui, Snawar Hussain, Shahid Pervez, Graeme Alexander

Department of Biological & Biomedical Sciences

Background: A disrupted cell cycle progression of hepatocytes was reported in chronic hepatitis C virus (HCV) infection, which can contribute significantly in the associated pathogenesis. The present study aimed to further elaborate these disruptions by evaluating the expression of key cell cycle and apoptotic proteins in chronic HCV infection with particular reference to genotype 3. Archival liver biopsy specimens of chronic HCV-infection (n = 46) and normal histology (n = 5) were analyzed by immunohistochemistry using antibodies against proliferation marker Mcm-2, G1 phase marker Cyclin D1, S phase marker Cyclin A, cell cycle regulators p21 (CDK inhibitor) and p53 (tumor …

Ginger Facilitates Cholinergic Activity Possibly Due To Blockade Of Muscarinic Autoreceptors In Rat Stomach Fundus, Muhammad N. Ghayur, Adil H. Khan, Anwarul H. Gilani

Department of Biological & Biomedical Sciences

Ginger (Zingiber officinale) is a universally known food plant reputed for its medicinal use in gastrointestinal disorders as a prokinetic and laxative. We recently showed that 70% aqueous-methanolic extract of ginger (Zo.Cr) exhibits prokinetic activity in rats via activation of post-synaptic muscarinic M3 receptor in rat stomach fundus. In view of the physiological significance of pre-synaptic muscarinic M1 and M2 autoreceptors, this study was undertaken to further look into the possible mode of action of the prokinetic effect of ginger through inhibition of pre-synaptic muscarinic receptors. Isolated tissue bath experiments were performed with Sprague-Dawley rat stomach fundus strip preparations immersed …

Hiv/Aids In Pakistan: The Battle Begins, Mohammad A. Rai, Haider J. Warraich, Syed H. Ali, Vivek R. Nerurkar

Department of Biological & Biomedical Sciences

Pakistan, the second most populous Muslim nation in the world, has started to finally experience and confront the HIV/AIDS epidemic. The country had been relatively safe from any indigenous HIV cases for around two decades, with most of the infections being attributable to deported HIV positive migrants from the Gulf States. However, the virus finally seems to have found a home-base, as evidenced by the recent HIV outbreaks among the injection drug user community. Extremely high-risk behavior has also been documented among Hijras (sex workers) and long-distance truck drivers. The weak government response coupled with the extremely distressing social demographics …

Total Parotidectomy Under Local Anesthesia: A Novel Technique, Kamran Shahid, Bilal Karim Siddiqui, Muhammad Hammad Tahir, Salman Bin Ayub, Ghulam Murtaza Memon, Adnan Yousuf, Arif Hussain, Osmani, Abdul Karim Siddiqui

Department of Biological & Biomedical Sciences

Parotidectomy is a common procedure usually done for a parotid mass necessitating a histological diagnosis. Operation is normally performed under General anesthesia with a nerve stimulator to facilitate facial nerve stimulation. We describe a new technique with reports of three cases, making total parotidectomy under local anesthesia possible. The ascending cervical branch of cervical plexus and the auriculotemporal nerve were anesthetized by bupivacaine 0.25% (2mg/kg) and lignocaine with adrenaline 7 mg/kg. Effective onset of anesthesia was within 15-25 minutes and the operations lasted between 2-3 hours without any complications. This offers advantage in high-risk patients where general anesthesia is contraindicated. …

Beta-Lactamase: An Ideal Reporter System For Monitoring Gene Expression In Live Eukaryotic Cells, Sohail A. Qureshi

Department of Biological & Biomedical Sciences

To gain insightful information about the mechanisms through which genes are activated and repressed requires gene reporter systems that are sensitive, robust, and cost-effective. Although numerous reporter gene technologies are commercially available, none are as sophisticated and user-friendly as beta-lactamase (BLA) when it comes to studying gene expression in live cells. This article presents an overview of the BLA technology and describes how it can be exploited for studying rare events such as homologous recombination in somatic cells and be used to deliver any DNA sequence of choice anywhere within the genome.

Polymorphism Of Hla-Dr And Hla-Dq In Rheumatoid Arthritis Patients And Clinical Response To Methotrexate--A Hospital-Based Study, Azra Arif I Ali, Tariq Moatter, Jawed Altaf Baig, Ahmed Iqbal, Azmat Hussain, Mohammad Perwaiz Iqbal

Department of Biological & Biomedical Sciences

Objective: To investigate the frequency and distribution of DRB1 and DQB1 alleles in Patients with rheumatoid arthritis (RA) and analyze the relationship between clinical response to methotrexate (MTX) and the HLA-DR and HLA-DQ genotypes in these patients.
Methods: In this case-control study, the HLA-DRB1 and HLA-DQB1 polymorphism in 91 RA patients and 91 healthy controls was done using polymerase chain reaction and sequence specific primers.
Results: There was no statistical difference in frequencies of HLA-DRB1*03, DRB1*04, DRB1*07, DRB1*10, DRB1*11, DRB1*12, DRB1*13, DRB1*14, DRB1*15 and DRB1*16 genotypes between patients and controls. However, DRB1*01 was found to be significantly more common (p=0.015) …

Hyperhomocysteinemia And Coronary Artery Disease In Pakistan, M Perwaiz Iqbal

Department of Biological & Biomedical Sciences

The relative risk of developing coronary artery disease (CAD) in Pakistani men is highest in early ages. Majority of those suffering from CAD belong to the lower middle socioeconomic stratum of the society. Mild hyperhomocysteinemia (concentration of plasma homocysteine between 15-25 micromol/l) is very commonly seen in Pakistani patients with acute myocardial infarction (AMI) as well as in normal healthy subjects. There appears to be a lack of association between hyperhomocysteinemia and CAD in Pakistani population. There is also no evidence of association of methylenetetrahydrofolate reductase 677C>T mutation with CAD in this population. High prevalence of deficiency of folate …

Critical Evaluation Of The Claims Made By Pharmaceutical Companies In Drug Promotional Material In Pakistan, Dileep Kumar Rohra, Anwarul Hassan Gilani, Ismail Kamal Memon, Ghazala Perven, Muhammad Talha Khan, Hina Zafar, Rakesh Kumar

Department of Biological & Biomedical Sciences

Background: In Pakistan, there is no mechanism to monitor the drug promotional campaign by pharmaceutical industry despite the fact that there is enough evidence that irrational pharmacotherapy is increasingly encountered even in the developed countries due to unethical practices of pharmaceutical promotion. Objectives. To audit the drug promotional claims made by the pharmaceutical companies in Pakistan.
Methods: Drug promotional pamphlets and brochures containing claims for the drugs, which were circulated by the pharmaceuticalrepresentatives were collected from 122 general practitioners (GPs) from Karachi and Larkana cities of the Sindh Province. The claims were critically analyzed and audited with the help of …

[3120+1kbdel86kb]+[Pn1303k] Genotype In An Emirati Cystic Fibrosis Patient: Indication Of A Founder Mutation In Palestinian Arabs, Danish Saleheen, Philippe M. Frossard, Emmanuelle Girodon

Department of Biological & Biomedical Sciences

Cystic fibrosis (CF) is the most common life-limiting autosomal recessive disorder in Caucasian population. The disease was initially considered to be rare in Middle Eastern countries. 95% of CF in Emirati families is due to two mutations only--p.S549R(T > G) and p.F508del. We report here the case of a patient referred to CF and Respiratory Clinic at Tawam Hospital for cystic fibrosis transmembrane regulator (CFTR) gene screening to ascertain the diagnosis of CF, who was found to carry a unique genotype, signifying the importance of retrieving ancestral histories of patients with monogenic disorders.

Hiv-1 Subtype A Infection In A Community Of Intravenous Drug Users In Pakistan, Saeed Khan, Mohammad A. Rai, Mohammad R. Khanani, Muhammad N. Khan, Syed H. Ali

Department of Biological & Biomedical Sciences

Background: Data on the subtypes of HIV in a population help in predicting the potential foci of epidemic, tracking the routes of infection and following the patterns of the virus' genetic divergence. Globally, the most prevalent HIV infection is the HIV-1 subtype C. In Asia, predominant subtypes of HIV-1 are B, C, and CRF-01AE. During the last few years, HIV prevalence in Pakistan has taken the form of a concentrated epidemic in at least two high risk groups, namely, Intravenous Drug Users (IDUs) and Male Sex Workers (MSWs). Factors that have facilitated the proliferation of HIV infection include transmission through …

Fractals Analysis Of Cardiac Arrhythmias, Mohammed Saeed

Department of Biological & Biomedical Sciences

Heart rhythms are generated by complex self-regulating systems governed by the laws of chaos. Consequently, heart rhythms have fractal organization, characterized by self-similar dynamics with long-range order operating over multiple time scales. This allows for the self-organization and adaptability of heart rhythms under stress. Breakdown of this fractal organization into excessive order or uncorrelated randomness leads to a less-adaptable system, characteristic of aging and disease. With the tools of nonlinear dynamics, this fractal breakdown can be quantified with potential applications to diagnostic and prognostic clinical assessment. In this paper, I review the methodologies for fractal analysis of cardiac rhythms and …

Lack Of Association Of Methylenetetrahydrofolate Reductase 677c>T Mutation With Coronary Artery Disease In A Pakistani Population, M Perwaiz Iqbal, Tasneem Fatima, Siddiqa Parveen, Farzana A. Yousuf, Majid Shafiq, Naseema Mehboobali, Abrar H. Khan, Iqbal Azam, Philippe M. Frossard

Department of Biological & Biomedical Sciences

Pakistanis belong to the South Asian population which has the highest known rate of coronary artery disease. Folic acid deficiency also appears to be highly prevalent in this population. Methylenetetrahydrofolate reductase (MTHFR) 677C>T polymorphism decreases the activity of this enzyme and can be associated with mild to moderate hyperhomocysteinemia in homozygotes, particularly when there is folic acid deficiency, as well as with coronary artery disease. To assess the value of genotyping the MTHFR 677C>T dimorphism, we carried out a case-control study of dimorphism 677C>T for putative association with myocardial infarction (MI) among Pakistani nationals. We investigated a …

Variability In Lipid Profile Before And After Coronary Artery Bypass Grafting (Cabg), M Perwaiz Iqbal, Hasanat Mohammad Sharif, Naseema Mehboobali

Department of Biological & Biomedical Sciences

Objective: To investigate changes in total cholesterol, low density lipoprotein (LDL) cholesterol, high density lipoprotein (HDL) cholesterol, and triglycerides in serum of Pakistani patients before, immediately after and 5 days post CABG.
Method: Serum samples from 31 consecutive Pakistani angina patients undergoing CABG at the Aga Khan University Hospital were analyzed for total cholesterol, LDL cholesterol, HDL cholesterol and triglycerides using kit methods.
Results: Immediately after CABG, there is a significant decline in the mean levels of serum cholesterol, LDL cholesterol, HDL cholesterol and triglycerides. However, 5 days post CABG, there is a significant increase in the concentrations of total …

Biochemical Screening For The Prediction Of Preeclampsia, Dileep Kumar Rohra, Nazia Qidwai

Department of Biological & Biomedical Sciences

No abstract provided.

Gene Markers And Complex Disorders: A Review, M S. Mahmood, N Kureshi, P M. Frossard

Department of Biological & Biomedical Sciences

No abstract provided.

Variability In Lipid Profile In Patients With Acute Myocardial Infarction From Two Tertiary Care Hospitals In Pakistan, M P. Iqbal, M Shafiq, N Mehboobali, S P. Iqbal, K Abbasi

Department of Biological & Biomedical Sciences

Objective: To investigate changes in total cholesterol, high density lipoprotein (HDL)-cholesterol, low density lipoprotein (LDL)-cholesterol and triglycerides in serum of Pakistani patients with AMI due to age, gender, body mass index (BMI), diabetes, hypertension, and smoking, and also find out the prevalence of hypercholesterolemia, hypertriglyceridemia, "low HDL-cholesterol" and "isolated low-HDL cholesterol" in them.
Patients and Methods: Serum samples from 451 consecutive AMI patients (250 from National Institute of Cardiovascular Diseases, Karachi and 201 from Armed Forces Institute of Cardiology, Rawalpindi) were analyzed for total cholesterol, HDL-cholesterol and triglycerides using kit methods. LDL-cholesterol was determined using the Friedewald formula.
Results: Mean …

Cystic Breast Lymphangioma, S N. Waqar, H Khan, S F. Mekan, N Kayani, A J. Raja

Department of Biological & Biomedical Sciences

No abstract provided.

Immunity In Medicine, M Saeed

Department of Biological & Biomedical Sciences

No abstract provided.

Involvement Of Thromboxane A2 And Tyrosine Kinase In The Synergistic Interaction Of Platelet Activating Factor And Calcium Ionophore A23187 In Human Platelet Aggregation, Huma Rasheed, Sheikh Arshad Saeed

Department of Biological & Biomedical Sciences

The present study was carried out to examine the mechanisms of the synergistic interaction of PAF and A23187 mediated platelet aggregation. We found that platelet aggregation mediated by subthreshold concentrations of PAF (5 nM) and A23187 (1 mM) was inhibited by PAF receptor blocker (WEB 2086, IC50 = 0.65 mM) and calcium channel blockers, diltiazem (IC50 = 13 mM) and verapamil (IC50 = 18 mM). Pretreatment of platelets with PAF and A23187 induced rise in intracellular calcium and this effect was also blocked by verapamil. While examining the role of the down stream signaling pathways, we found that platelet aggregation …

Increased Levels Of Erythrocyte Glutathione In Acute Myocardial Infarction: An Antioxidant Defence, M P. Iqbal, M Ishaq, N Mehboobali

Department of Biological & Biomedical Sciences

Objective: Glutathione (GSH) has a central role in the defence against oxidative damage. This study was carried out to investigate any change in erythrocyte GSH levels in a population of patients with acute myocardial infarction (AMI) and compare them with levels in normal healthy subjects.
Method: GSH levels were determined in erythrocytes of one hundred and seventy six patients with AMI (age: 30-70 years; 131 males and 45 females) admitted to the National Institute of Cardiovascular Diseases, Karachi. These levels were compared with eryrocyte GSH levels obtained from 95 normal healthy subjects (controls).
Results: Mean +/- SD erythrocyte GSH levels …

Association Study Of The Angiotensin-Converting Enzyme (Ace) Gene G2350a Dimorphism With Myocardial Infarction, M Perwaiz Iqbal, Saeed Mahmood, Naseema Mehboobali, Mohammad Ishaq, Tasnim Fatima, Saddiqa Parveen, Philippe Frossard

Department of Biological & Biomedical Sciences

The angiotensin converting enzyme (ACE) is a strong candidate gene for myocardial infarction (MI). Insertion-deletion dimorphism in intron 16 of this gene has been inconclusively found to be associated with it. Several new polymorphisms in the ACE gene have been identified and among these, a dimorphism in exon 17, ACE G2350A, has a significant effect on plasma ACE concentrations. To assess the value of genotyping the ACE G2350A dimorphism in a genetically homogeneous population, we carried out a case-control study of dimorphism G2350A for a putative association with MI among Pakistani nationals. We investigated a sample population of 370 Pakistanis, …

Core Concepts In Biochemistry And Molecular Biology In An Integrated Mbbs Curriculum, M P. Iqbal

Department of Biological & Biomedical Sciences

No abstract provided.