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Adnan F, Khan NU, Iqbal A, Ali I, Petruzziello A, Sabatino R, Guzzo A, Loquercio G, Botti G, Khan S, Naeem M, Khan MI. Interleukin-6 polymorphisms in HCC patients chronically infected with HCV. Infect Agent Cancer 2020; 15:21. [PMID: 32266003 PMCID: PMC7114800 DOI: 10.1186/s13027-020-00285-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Accepted: 03/19/2020] [Indexed: 02/07/2023] Open
Abstract
Hepatocellular carcinoma is a primary liver malignancy in which the risk of development is always multifunctional. Interleukin-6 is a proinflammatory and multifunctional cytokine, which plays an important role in the immune response, haematopoiesis and defence against viral infection. We aimed to evaluate the frequency of Interleukin-6 mutations (rs2069837 and rs17147230) associated with genetic risk of hepatocellular carcinoma in Khyber Pakthunkhwa population. A total of 72 hepatocellular carcinoma cases and 38 controls were included in this study. The genomic DNA was extracted from the peripheral blood cells and Interleukin-6 genotyping was performed using T-ARMS-PCR technique. Our results show a significant increase risk of developing hepatocellular carcinoma with the mutation within Interleukin-6 gene with heterozygous G allele (rs2069837) (OR = 10.667, 95%CI = 3.923–29.001, p = < 0.0001) and heterozygous T allele (rs17147230) (OR = 75.385, 95%CI = 9.797–580.065, p = < 0.0001). However, under recessive gene model the results were insignificant in case of Interleukin-6 rs2069837 (OR = 0.605, 95%CI = 0.217–1.689, p = 0.337), while significant in case of Interleukin-6 rs17147230 (OR = 0.298, 95%CI = 0.121–0.734, p = 0.0085). In conclusion, Interleukin-6 mutation is associated with hepatocellular carcinoma susceptibility. More related studies with other associated interleukins and their whole gene sequencing will be required.
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Petruzziello A, Loquercio G, Sabatino R, Balaban DV, Ullah Khan N, Piccirillo M, Rodrigo L, di Capua L, Guzzo A, Labonia F, Botti G. Prevalence of Hepatitis C virus genotypes in nine selected European countries: A systematic review. J Clin Lab Anal 2019; 33:e22876. [PMID: 30843304 PMCID: PMC6595292 DOI: 10.1002/jcla.22876,] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND Hepatitis C virus (HCV) infection is a global health problem especially for its increasing level of mortality. Detailed knowledge of HCV genotypes prevalence has clinical relevance since the efficacy of therapies is impacted by genotypes and subtypes distribution. Moreover, HCV exhibits a great genetic variability regionally. To date, there are no published studies assessing HCV genotypes distribution in specific countries of the Mediterranean basin. The aim of this study was to review data published from 2000 to 2017 with the purpose to estimate genotypes distribution of HCV infection in nine European countries all located in the Mediterranean basin. METHODS A systematic research of peer-reviewed journals indexed in PubMed, Scopus, and EMBASE databases selected if containing data regarding distribution of HCV genotypes in nine selected European countries (Albania, Bosnia, Croatia, France, Greece, Italy, Montenegro, Slovenia, and Spain) was performed. RESULTS Genotype 1 is the most common (61.0%), ranging from 80.0% in Croatia to 46.0% in Greece, followed by genotype 3 (20.0%), varying from 38.0% in Slovenia to 7.0% and 8.0%, respectively, in Italy and in Albania and by genotype 4 (10.0%) that shows an increase of 1.1% with respect to data obtained till 2014 probably due to the increasing migrants arrivals to Southern Europe. G2, the fourth most frequent genotype (8.5%), particularly common in Italy (27.0%) and Albania (18.0%) might be probably introduced in Southern Italy as a result of Albanian campaign during Second World War and more and more increased by the migration flows from Albania to Italy in the 90s. CONCLUSION Epidemiology of HCV infection shows a high variability across the European countries that border the Mediterranean Sea. HCV genotyping is a relevant tool to monitor the dynamic process influenced by both evolving transmission trends and new migration flows on HCV scenario.
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Petruzziello A, Loquercio G, Sabatino R, Balaban DV, Ullah Khan N, Piccirillo M, Rodrigo L, di Capua L, Guzzo A, Labonia F, Botti G. Prevalence of Hepatitis C virus genotypes in nine selected European countries: A systematic review. J Clin Lab Anal 2019; 33:e22876. [PMID: 30843304 PMCID: PMC6595292 DOI: 10.1002/jcla.22876] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 02/08/2019] [Accepted: 02/11/2019] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND Hepatitis C virus (HCV) infection is a global health problem especially for its increasing level of mortality. Detailed knowledge of HCV genotypes prevalence has clinical relevance since the efficacy of therapies is impacted by genotypes and subtypes distribution. Moreover, HCV exhibits a great genetic variability regionally. To date, there are no published studies assessing HCV genotypes distribution in specific countries of the Mediterranean basin. The aim of this study was to review data published from 2000 to 2017 with the purpose to estimate genotypes distribution of HCV infection in nine European countries all located in the Mediterranean basin. METHODS A systematic research of peer-reviewed journals indexed in PubMed, Scopus, and EMBASE databases selected if containing data regarding distribution of HCV genotypes in nine selected European countries (Albania, Bosnia, Croatia, France, Greece, Italy, Montenegro, Slovenia, and Spain) was performed. RESULTS Genotype 1 is the most common (61.0%), ranging from 80.0% in Croatia to 46.0% in Greece, followed by genotype 3 (20.0%), varying from 38.0% in Slovenia to 7.0% and 8.0%, respectively, in Italy and in Albania and by genotype 4 (10.0%) that shows an increase of 1.1% with respect to data obtained till 2014 probably due to the increasing migrants arrivals to Southern Europe. G2, the fourth most frequent genotype (8.5%), particularly common in Italy (27.0%) and Albania (18.0%) might be probably introduced in Southern Italy as a result of Albanian campaign during Second World War and more and more increased by the migration flows from Albania to Italy in the 90s. CONCLUSION Epidemiology of HCV infection shows a high variability across the European countries that border the Mediterranean Sea. HCV genotyping is a relevant tool to monitor the dynamic process influenced by both evolving transmission trends and new migration flows on HCV scenario.
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Xie J, Li F, Khan NU, Zhu X, Wang X, Zhang Z, Ma X, Zhao Y, Zhang Q, Zhang S, Zhang Z, Li J, Li Z, Zhang H. Identifying natural genotypes of grain number per panicle in rice (Oryza sativa L.) by association mapping. Genes Genomics 2018; 41:283-295. [PMID: 30456522 DOI: 10.1007/s13258-018-0758-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Accepted: 10/29/2018] [Indexed: 10/27/2022]
Abstract
INTRODUCTION As one of the main yield components, grain number per panicle (GNP) played critical role in the rice yield improvement. The identification of natural advantageous variations under different situations will promote the sustainable genetic improvement in rice yield. OBJECTIVES This study was designed to identify natural genotypes in a rice mini-core collection, to examine the genotypic effects across the indica and japonica genetic background in different environments, and excavating the superior genotypes that had drove the modern genetic improvement. METHODS The association mapping of GNP was carried out using a mini-core collection including 154 indica and 119 japonica accessions in seven different environments. Genotypic effects of each genotype for each QTL were calculated and genotype frequency distortion between the commercial rice cultivars and landraces was screened by χ2-test. RESULTS In total, 74 QTLs containing stable and sensitive QTLs in various environments were detected. Within them, 20 positive and 24 negative genotypes in indica, and 24 positive and 16 negative genotypes in japonica were identified. When checking the accumulation of positive genotypes identified in indica across cultivars in each of the two subspecies, it indicated that increased number of positive genotypes identified in indica results in the substantially increased GNP in both indica and japonica across all of the environments, while this trend was not obvious for the positive genotypes identified in japonica especially in short day environments. Moreover, the positive and negative genotype frequency distortion between the landraces and commercial rice cultivars indicated that both positive selection of positive genotypes and negative selection of negative genotypes had driven the genetic improvement on GNP. CONCLUSION Our findings suggested that the accumulation of positive genotypes and purifying negative genotypes played equivalently important roles in the improvement of rice yield, but the efficient use for some QTLs or genotypes depends on the comprehensive evaluation of their effect under diverse genetic backgrounds and environments.
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Khan NU, Zalan A, Petruzziello A, Ud Din I, Haq F, Hayat Y. Determining the Actual Prevalence of Hepatitis B in Khyber Pakhtunkhwa-Pakistan: A Meta-Analysis. Open Virol J 2018; 12:33-41. [PMID: 29576813 PMCID: PMC5848220 DOI: 10.2174/1874357901812010033] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Revised: 09/26/2017] [Accepted: 12/28/2017] [Indexed: 02/07/2023] Open
Abstract
Background: Hepatitis B is considered the most dangerous among the five types of Hepatitis, as it is clinically asymptomatic. It can silently damage the liver over many years without being diagnosed. Hepatitis B is one of the top risks of liver complications in Khyber Pakhtunkhwa (KP), a province of Pakistan, with an average prevalence rate of 2.70%. Aims: We aimed to carefully review the previously published data on prevalence of Hepatitis B Virus (HBV) in KP-Pakistan and use the statistical approach to obtain more precise estimate of the prevalence of HBV in KP-Pakistan. This study on one hand will provide a more reliable and consolidated estimate (pooled estimate) of HBV in the stated region, on the other hand, it enabled us to judge the heterogeneity among the estimates found from these studies. The study is intended to provide more authentic prevalence record and help government/ non-government organizations and health professionals, which plan to initiate HBV prevention programs in KP-Pakistan. Methods: A meta-analysis was performed based on studies found in literature search from electronic databases and bibliography on the prevalence of HBV in KP-Pakistan from 2007 to 2017. Abstracts and results of twenty papers were thoroughly studied and the data were extracted. The findings from these studies were distributed in two groups (general and population at high risk) constituting 15 and 5 studies respectively. Results: The combined prevalence by considering random model for the general population of KP-Pakistan was observed to be 2.71%, while population at high risk was reasonably high i.e. 5.64%. By comparing this prevalence rate to the highest global prevalence of HBV in the adult population of Western Pacific Region (6.2%), significant (p-value= 0.000) heterogeneity was observed among the estimates in each group. However, the funnel plot provides a symmetric look, eliminating the effect of publication bias. We can say that HBV has an alarming prevalence rate in KP-Pakistan. However, HBV is thrice more prevalent in male population of KP-Pakistan than the female population. Conclusion: The above results lead that HBV infection has reached an alarming state in KP-Pakistan, though projects like Prime Minister’s Program for Prevention & Control of Hepatitis which are contributing in improving the health of the people of KP by trying to prevent and control the incidence of HBV. More massive vaccination and awareness programs should be initiated to prevent the spread of HBV on urgent basis. Provision of diagnostics and treatment facilities against HBV in healthcare units of KP-Pakistan should be assured.
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Liu M, Khan NU, Wang N, Yang X, Qiu D. The Protein Elicitor PevD1 Enhances Resistance to Pathogens and Promotes Growth in Arabidopsis. Int J Biol Sci 2016; 12:931-43. [PMID: 27489497 PMCID: PMC4971732 DOI: 10.7150/ijbs.15447] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Accepted: 05/12/2016] [Indexed: 11/20/2022] Open
Abstract
The protein elicitor PevD1, isolated from Verticillium dahlia, could enhance resistance to TMV in tobacco and Verticillium wilt in cotton. Here, the pevd1 gene was over-expressed in wild type (WT) Arabidopsis, and its biological functions were investigated. Our results showed that the transgenic lines were more resistant to Botrytis cinerea and Pseudomonas syringae pv. tomato DC3000 than the WT line was. In transgenic plants, both the germination time and bolting time required were significantly shorter and fresh weights and plant heights were significantly higher than those in the WT line. A transcriptomics study using digital gene expression profiling (DGE) was performed in transgenic and WT Arabidopsis. One hundred and thirty-six differentially expressed genes were identified. In transgenic Arabidopsis, three critical regulators of JA biosynthesis were up-regulated and JA levels were slightly increased. Three important repressors of the ABA-responsive pathway were up-regulated, indicating that ABA signal transduction may be suppressed. One CML and two WRKY TFs involved in Ca2+-responsive pathways were up-regulated, indicating that this pathway may have been triggered. In conclusion, we show that PevD1 is involved in regulating several plant endogenous signal transduction pathways and regulatory networks to enhance resistance and promote growth and development in Arabidopsis.
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Khan NU, Shakeel N, Makda A, Mallick AS, Ali Memon M, Hashmi SH, Khan UR, Razzak JA. Anaphylaxis: incidence, presentation, causes and outcome in patients in a tertiary-care hospital in Karachi, Pakistan. QJM 2013; 106:1095-101. [PMID: 24082151 PMCID: PMC3840329 DOI: 10.1093/qjmed/hct179] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Anaphylaxis is a potentially fatal condition requiring immediate resuscitation. Data regarding the epidemiology of anaphylaxis are limited and inconsistent. A reason for the variability was unavailability of a universally acceptable case definition till 2005. We reviewed cases using this new definition AIM To review the incidence, clinical presentation, cause and outcome of anaphylaxis at a tertiary-care centre in a low-income country. DESIGN Retrospective, case series METHODS Chart review of all patients discharged from Aga Khan University Hospital between January 1988 and December 2012 (24 years) with anaphylaxis definition as per second National Institute of Allergy and Infection disease/Food Allergy and Anaphylaxis Network Symposium RESULTS Total of 129 cases were found with mean age of 41.6 years (SD 18.8). Majority of patients had cutaneous features (76.7%), followed by respiratory (68.9%), cardiac (64.3%) and gastrointestinal (20.9%) symptoms, respectively. About 22.4% of patients had positive history for allergens out of which 31% (n = 9) were exposed to the same allergens. The common causes identified for anaphylaxis were drugs (60.5%), food (16.3%) and intravenous contrast (10.9%), respectively. Only 22.5% of cases received epinephrine as a part of their initial management. In four patients (3.1%) the cause of death was attributed to anaphylaxis. CONCLUSION Anaphylaxis is a rare but life-threatening condition. Though cutaneous features are most common, their absence does not exclude the diagnosis. Drugs were the most common cause and epinephrine was not commonly used as first-line agent for its management.
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Khan NU, Khan FA, Khan DA, Asim N. Pregnancy-associated plasma protein-A levels in individuals with and without coronary artery disease. JCPSP-JOURNAL OF THE COLLEGE OF PHYSICIANS AND SURGEONS PAKISTAN 2011; 21:450-4. [PMID: 21798128 DOI: 08.2011/jcpsp.450454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 11/11/2010] [Accepted: 06/24/2011] [Indexed: 11/22/2022]
Abstract
OBJECTIVE To compare pregnancy-associated plasma protein-A (PAPP-A) levels in individuals with and without coronary artery disease (CAD). STUDY DESIGN Cross-sectional comparative study. PLACE AND DURATION OF STUDY Department of Chemical Pathology and Endocrinology, Armed Forces Institute of Pathology (AFIP), Rawalpindi, in collaboration with Armed Forces Institute of Cardiology (AFIC), from September 2008 to March 2010. METHODOLOGY One hundred and twenty five (125) individuals both male and female were included in the study. Blood for PAPP-A and lipid profile was collected, just before angiography. On the basis of angiography, the individuals were divided into those with and without CAD. PAPP-A was analyzed by using Diagnostic System Laboratories (DSL) Enzyme Linked Immunosorbent Assay (ELISA) kit and reading was taken by ELISA reader. Lipid profile was determined on automated analyzers Selectra-2 and Vitros 5.1. RESULTS Amongst the 125 individuals, 41 individuals were without CAD whereas 84 individuals were having CAD. Mean PAPP-A levels were 0.74 ± 0.35 mIU/L in those without CAD whereas mean PAPP-A levels in those with CAD were 1.35 ± 0.57 mIU/L. The difference between the two groups was statistically significant (p < 0.001). A PAPP-A cut off level of 0.85 mIU/L had a sensitivity and specificity of 78% and 70% respectively for diagnosing atherosclerotic CAD. CONCLUSION PAPP-A is a potentially relevant marker of the presence and extent of coronary atherosclerosis as its levels are elevated in CAD as compared to individuals without CAD.
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Khan AA, Khan NU, Bile KM, Awan H. Creating synergies for health systems strengthening through partnerships in Pakistan--a case study of the national eye health programme. EASTERN MEDITERRANEAN HEALTH JOURNAL = LA REVUE DE SANTE DE LA MEDITERRANEE ORIENTALE = AL-MAJALLAH AL-SIHHIYAH LI-SHARQ AL-MUTAWASSIT 2010; 16 Suppl:S61-S68. [PMID: 21495590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Blindness and visual impairment are major causes of noncomrnunicable diseases in Pakistan. Two national population-based blindness surveys conducted in 1988 and 2002-04 demonstrated a reduction in prevalence of blindness from 1.78% to 0.9% with a significant drop in cataract blindness as a result of accelerated nationwide interventions and eye care integration in primary health care. In addition, between 2006 and 2008, 88 facilities were upgraded as a result of the national eye health programme. These measures resulted in a 279% increase in eye outpatient attendances and a 375% increase in eye surgeries performed. Investment in human resources development and policy change contributed significantly to the sustainability of the programme. Key challenges facing the programme include aligning national eye health strategies with health system strengthening informed through health systems research. This paper attempts to document this extraordinary success.
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Azam S, Hadi N, Khan NU, Hadi SM. Prooxidant property of green tea polyphenols epicatechin and epigallocatechin-3-gallate: implications for anticancer properties. Toxicol In Vitro 2005; 18:555-61. [PMID: 15251172 DOI: 10.1016/j.tiv.2003.12.012] [Citation(s) in RCA: 256] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2003] [Accepted: 12/30/2003] [Indexed: 10/26/2022]
Abstract
It is believed that anticancer and apoptosis inducing properties of green tea are mediated by it's polyphenolic constituents particularly catechins. A number of reports have shown that green tea polyphenol (-)-epigallocatechin-3-gallate (EGCG) is among the most effective chemopreventive and apoptosis-inducing agents present in the beverage. Plant polyphenols are naturally occurring antioxidants but they also exhibit prooxidant properties. Over the last several years we have shown that various classes of plant polyphenols including flavonoids, curcuminoids and tannins are capable of catalyzing oxidative DNA cleavage particularly in the presence of transition metal ions such as copper and iron. With a view to understand the chemical basis of various pharmacological properties of green tea, in this paper we have compared the prooxidant properties of green tea polyphenols--EGCG and EC ((-)-epicatechin). The rate of oxidative DNA degradation as well as hydroxyl radical and superoxide anion formation was found to be greater in the case of EGCG as compared with EC. It was also shown that copper mediated oxidation of EC and EGCG possibly leads to the formation of polymerized polyphenols. Further, it was indicated that copper oxidized catechins were more efficient prooxidants as compared with their unoxidized forms. These results correlate with the observation by others that EGCG is the most effective apoptosis inducing polyphenol present in green tea. They are also in support of our hypothesis that prooxidant action of plant polyphenols may be an important mechanism of their anticancer properties. A model for binding of Cu(II) to EC has been presented where the formation of quinone and a quinone methide has been proposed.
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Uddin Q, Malik A, Azam S, Hadi N, Azmi AS, Parveen N, Khan NU, Hadi SM. The biflavonoid, amentoflavone degrades DNA in the presence of copper ions. Toxicol In Vitro 2004; 18:435-40. [PMID: 15130600 DOI: 10.1016/j.tiv.2003.12.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2003] [Accepted: 12/23/2003] [Indexed: 11/26/2022]
Abstract
Previous reports from this laboratory have shown that flavonoids including apigenin are capable of inducing oxidative DNA cleavage in the presence of copper ions. In the present report, we have examined the ability of amentoflavone, a biflavonoid which is a dimer of apigenin, to catalyze the degradation of DNA. Amentoflavone was found to degrade calf thymus DNA in the presence of Cu(II) at a rate almost twice that of apigenin. Amentoflavone was also shown to reduce Cu(II) to Cu(I) and to generate hydroxyl radicals in the presence of copper ions. In the presence of Cu(II), the absorption spectrum of amentoflavone undergoes a shift and a quenching effect indicating that the biflavonoid is capable of binding to copper ions. Amentoflavone and apigenin were isolated from Cycas rumphii and Trifolium alexandrinum, respectively. The results are discussed in relation to the putative chemopreventive mechanism of amentoflavone.
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Hadi N, Malik A, Azam S, Khan NU, Iqbal J. Serotonin-Cu(II)-mediated DNA cleavage: mechanism of copper binding by serotonin. Toxicol In Vitro 2002; 16:669-74. [PMID: 12423649 DOI: 10.1016/s0887-2333(02)00083-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
It has been proposed that considerable DNA damage may be caused by endogenous metabolites produced during the body's normal metabolic processes. 5-hydroxytryptamine (serotonin) is an important neurotransmitter in brain and spinal cord. We have previously shown that serotonin induces oxidative cleavage of DNA strands in the presence of copper ions. In the present paper we have examined the mechanism of copper binding by serotonin using absorption spectroscopy, Cu(II)-mediated lipid peroxidation and by determining the oxidation of the serotonin molecule. Addition of increasing concentrations of Cu(II) to serotonin leads to a progressive enhancement in the absorption band and is accompanied by a shift towards a lower wavelength indicative of the formation of an oxidised species of serotonin. Studies with the structurally related molecules tryptophan and melatonin showed that only serotonin is able to reduce Cu(II) to Cu(I). Similarly, only serotonin was found to be able to abolish the copper-mediated peroxidation of mitochondria. These results suggested the involvement of the phenolic group in copper binding. Further, it was also shown that the binding of copper to serotonin leads to the formation of a quinone in the absence of molecular oxygen. Based on these results, a model has been proposed in which serotonin reduces two molar equivalents of Cu(II) to Cu(I) through a reaction involving two electron oxidation of the phenolic ring to a quinone methide.
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Parveen N, Khan NU, Singhal KC. Potential antifilarial activity of the leaves and seeds extracts of Psoralea corylifolia on cattle filarial parasite Setaria cervi. JOURNAL OF ETHNOPHARMACOLOGY 2002; 82:23-28. [PMID: 12169401 DOI: 10.1016/s0378-8741(02)00141-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The effect of aqueous and alcohol extracts of the leaves and seeds of Psoralea corylifolia, on the spontaneous movements of both the whole worm and the nerve muscle preparation of Setaria cervi and on the survival of microfilariae in vitro was studied. Alcohol extracts of both leaves and seeds caused the inhibition of spontaneous movements of the whole worm and the nerve muscle preparation of S. cervi, characterised by initial, short lasting small increase in tone of contractions followed by paralysis. The initial stimulatory effect was not observed by alcohol extract of leaves on nerve muscle preparation. The concentrations required to inhibit the movements of whole worm and nerve muscle preparations for alcohol extracts of leaves and seeds were 160, 30, and 150, 20 microg/ml, respectively suggesting a cuticular permeability barrier. Alcohol extracts of both leaves and seeds caused death of microfilariae in vitro, LC(50) and LC(90) being 15 and 25 ng/ml for alcohol extract of leaves and 12 and 18 ng/ml for alcohol extract of seeds, respectively.
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Zamvar V, Deglurkar I, Abdullah F, Khan NU. Bleeding from the lung surface: a unique complication of off-pump CABG operation. Heart Surg Forum 2001; 4:172-3. [PMID: 11544619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2000] [Indexed: 02/21/2023]
Abstract
A patient, with post myocardial infarction (MI) thrombolysis, underwent emergency off-pump coronary artery bypass graft. Her post-operative course was complicated by excessive bleeding. At re-exploration, the bleeding was caused by a graze on the lung surface by the needle used during the insertion of the deep pericardial retraction suture.
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Singh S, Asad SF, Ahmad A, Khan NU, Hadi SM. Oxidative DNA damage by capsaicin and dihydrocapsaicin in the presence of Cu(II). Cancer Lett 2001; 169:139-46. [PMID: 11431102 DOI: 10.1016/s0304-3835(01)00544-4] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Capsaicin is the pungent phenolic principle of the Capsicum species, and has shown a wide range of pharmacological properties, including antigenotoxic, antimutagenic, and anticarcinogenic effects. Other studies have, however, shown it to be a tumor promoter and potential mutagen, and a carcinogen, resulting in capsaicin being termed a 'double edged sword'. In the present study, we show that capsaicin is capable of causing strand scission in calf thymus and plasmid DNA in the presence of Cu(II) and that this breakage is mediated by reactive oxygen species, especially the hydroxyl radical. Our results further show that capsaicin can directly generate hydroxyl radicals in the presence of Cu(II). To explore the chemical basis of the DNA breakage reaction by capsaicin, we have compared these properties of capsaicin with its saturated structural analog dihydrocapsaicin (DHC). The rate of DNA degradation, as well as hydroxyl radical formation, was found to be greater in the case of capsaicin. Both capsaicin and DHC are able to reduce Cu(II) to Cu(I), which was shown to be an essential intermediate in the DNA cleavage reaction. Stoichiometric analysis indicated that whereas 1 mol of capsaicin reduced 3 mol of Cu(II), 1 mol of DHC reduced only 2 mol of Cu(II). This explains the greater activity of capsaicin and also leads to a model for copper binding to the capsaicins.
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Asad SF, Singh S, Ahmad A, Khan NU, Hadi SM. Prooxidant and antioxidant activities of bilirubin and its metabolic precursor biliverdin: a structure-activity study. Chem Biol Interact 2001; 137:59-74. [PMID: 11518564 DOI: 10.1016/s0009-2797(01)00209-5] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Bilirubin, which is derived from its metabolic precursor biliverdin, is the end product of heme catabolism. It has been proposed as a physiological antioxidant present in human extracellular fluids. We have earlier shown that bilirubin in the presence of the transition metal ion Cu(II) causes strand cleavage in DNA through generation of reactive oxygen species, particularly the hydroxyl radical. Thus bilirubin possesses both antioxidant and prooxidant properties. In order to understand the chemical basis of various biological properties of bilirubin, we have studied the structure-activity relationship between bilirubin and its precursor biliverdin. The latter has also been reported to possess both antioxidant and toxic properties. In the present studies bilirubin was found to be more effective in the DNA cleavage reaction and a more efficient reducer of Cu(II). The rate of formation of hydrogen peroxide and hydroxyl radicals by the compounds also showed a similar pattern. The relative antioxidant activity was also examined by studying the effect of these compounds on DNA cleavage by a hydroxyl radical generating system and their quenching effect on hydroxyl radicals. The results indicate that bilirubin is more active both as an antioxidant as well as an oxidative DNA cleaving agent. A model for binding of copper to bilirubin has been proposed where two copper ions are bound to two molecules of bilirubin through their terminal pyrrole nitrogens. In order to account for the enhanced copper reducing capacity of bilirubin we have further proposed that an additional copper binding site is provided for in the case of bilirubin due to the absence of a double bond between pyrrole rings II and III. Further it would appear that the structural features of the bilirubin molecule which are important for its prooxidant action are also the ones that render it a more effective antioxidant.
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Singh R, Singhal KC, Khan NU. Exploration of antifilarial potential and possible mechanism of action of the root extracts of Saxifraga stracheyion on cattle filarial parasite Setaria cervi. Phytother Res 2000; 14:63-6. [PMID: 10641054 DOI: 10.1002/(sici)1099-1573(200002)14:1<63::aid-ptr567>3.0.co;2-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The effect of aqueous and alcohol extracts of the roots of Saxifraga stracheyi Engl. On the spontaneous movements of both the whole worm and the nerve muscle preparation of Setaria cervi and on the survival of microfilariae in vitro was studied. Both extracts caused the inhibition of spontaneous movements of the whole worm and the nerve-muscle preparation of S. cervi, characterized by an increase in the amplitude and a decrease in the rate of contractions, while the tone of the contractions remained visibly unaffected. The concentration required to inhibit the movements of the whole worm preparation was 140 microg/ml for the aqueous and 250 microg/ml for the alcohol extract. The concentration of S. stracheyi extracts required to produce an equivalent effect on the nerve-muscle preparation was 30 microg/ml for aqueous, and 20 microg/ml for the alcohol extract, suggesting a cuticular permeability barrier.
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Jain A, Martin MC, Parveen N, Khan NU, Parish JH, Hadi SM. Reactivities of flavonoids with different hydroxyl substituents for the cleavage of DNA in the presence of Cu(II). Phytother Res 1999; 13:609-12. [PMID: 10548756 DOI: 10.1002/(sici)1099-1573(199911)13:7<609::aid-ptr566>3.0.co;2-i] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
DNA strand scission reactions of flavonoids in the presence of Cu(II) have been extended by using flavonoids with a variety of patterns of hydroxyl substitution. In particular we have examined for the first time a flavonoid (7,8-dihydroxyflavone) that lacks the possibility of forming a complex involving the oxygen at position 4. By comparing the reactivities of several flavonoids, including data from the literature, we draw generalizations for the correlation of structure and activity and present evidence for at least three different modes of action of flavonoids as genotoxic agents.
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Ahsan H, Parveen N, Khan NU, Hadi SM. Pro-oxidant, anti-oxidant and cleavage activities on DNA of curcumin and its derivatives demethoxycurcumin and bisdemethoxycurcumin. Chem Biol Interact 1999; 121:161-75. [PMID: 10418962 DOI: 10.1016/s0009-2797(99)00096-4] [Citation(s) in RCA: 194] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Curcumin, a naturally occurring phytochemical responsible for the colour of turmeric shows a wide range of pharmacological properties including antioxidant, anti-inflammatory and anti-cancer effects. We have earlier shown that curcumin in the presence of Cu(II) causes strand cleavage in DNA through generation of reactive oxygen species, particularly the hydroxyl radical. Thus, curcumin shows both antioxidant as well as pro-oxidant effects. In order to understand the chemical basis of various biological properties of curcumin, we have studied the structure-activity relationship between curcumin and its two naturally occurring derivatives namely demethoxycurcumin (dmC) and bisdemethoxycurcumin (bdmC). Curcumin was found to be the most effective in the DNA cleavage reaction and a reducer of Cu(II) followed by dmC and bdmC. The rate of formation of hydroxyl radicals by the three curcuminoids also showed a similar pattern. The relative antioxidant activity was examined by studying the effect of these curcuminoids on cleavage of plasmid DNA by Fe(II)-EDTA system (hydroxyl radicals) and the generation of singlet oxygen by riboflavin. The results indicate that curcumin is considerably more active both as an antioxidant as well as an oxidative DNA cleaving agent. The DNA cleavage activity is the consequence of binding of Cu(II) to various sites on the curcumin molecule. Based on the present results, we propose three binding sites for Cu(II). Two of the sites are provided by the phenolic and methoxy groups on the two benzene rings and the third site is due to the presence of 1,3-diketone system between the rings. Furthermore, both the antioxidant as well as pro-oxidant effects of curcuminoids are determined by the same structural moieties.
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Singh R, Singhal KC, Khan NU. Antifilarial activity of Mallotus philippensis Lam. on Setaria cervie (Nematoda: Filarioidea) in vitro. INDIAN JOURNAL OF PHYSIOLOGY AND PHARMACOLOGY 1997; 41:397-403. [PMID: 10235663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
The effect of aqueous and alcoholic extracts of the leaves of Mallotus philippensis (Lam.) Muell. Arg. was studied on the spontaneous movements of the whole worm and nerve-muscle (n.m.) preparation of Setaria cervi and on the survival of microfilariae in vitro. Both the extracts caused inhibition of spontaneous motility of whole worm and the n.m. preparation of S. Cervi characterized by initial stimulation followed by depression in amplitude. The tone and rate of contractions remained visibly unaffected. Aqueous extract at higher concentration showed immediate reduction in tone. The concentration required to inhibit the movements of n.m. preparation was 1/5th for aqueous and 1/11th for alcoholic extract compared to that for the whole worm, suggesting a cuticular permeability barrier. The stimulatory response of acetylcholine was blocked by aqueous extract on whole worm movements. On the microfilariae the LC50 and LC90 were 18 and 20 ng/ml for aqueous and 12 and 15 ng/ml for alcoholic extracts respectively.
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Singh R, Khan NU, Singhal KC. Potential antifilarial activity of roots of Asparagus adscendens Roxb, against Setaria cervi in vitro. INDIAN JOURNAL OF EXPERIMENTAL BIOLOGY 1997; 35:168-72. [PMID: 9315227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Effect of aqueous and alcoholic extracts of the roots of A. adscendens was studied on the spontaneous movements of whole worm and nerve muscle (n.m.) preparation of S. cervi and on the survival of microfilariae in vitro. Aqueous as well alcoholic extracts caused inhibition of spontaneous motility of whole worm and n.m. preparation of S. cervi characterized by initial, short lasting small increase in amplitude and tone of contractions followed by paralysis. The initial stimulatory effect was not observed by aqueous extract on n.m. preparation. The concentration required to inhibit the movements of n.m. preparation was 1/4th for aqueous and 1/3rd for alcoholic extract suggesting a cuticular permeability barrier. The effect of acetylcholine on n.m. preparation was concentration related being more with a concentration of 5 micrograms/ml as compared to 1 microgram/ml. Both alcoholic as well as aqueous extracts caused death of microfilariae in vitro, LC50 and LC90 being 8 and 16 ng/ml for aqueous, 3 and 12 ng/ml for alcoholic extracts respectively.
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Singh R, Khan NU, Singhall KC. In vitro antifilarial activity of Sencio nudicaulis Buch. Ham. Effect on Setaria cervi (Nematoda Filarioidea). INDIAN JOURNAL OF PHYSIOLOGY AND PHARMACOLOGY 1996; 40:231-6. [PMID: 8950138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The effect on aqueous and alcoholic extracts of the leaves of Sencio nudicaulis Buch. Ham. was studied on the spontaneous movements of the whole worm and nerve-muscle preparation of Setaria cervi and on the survival of micro-filariae in vitro. Aqueous as well as alcoholic extracts caused inhibition of spontaneous motility of the whole worm and nerve-muscle preparation of S. cervi characterized by decreased amplitude, rate and tone of contractions. The concentration required to inhibit the movements of n.m. preparation was 1/3rd for aqueous and 1/20th for alcoholic extract suggesting a cuticular permeability barrier. The effect of S nudicaulis extracts was different than that produced by calcium channel blocker nifedipine on the whole worm and n.m. preparation. While nifedipine blocks the stimulant effect of Ach the extracts of S. nudicaulis fails to do so. While the response bears similarity with DEC which also does not block Ach response. Both aqueous and alcoholic extracts exhibited microfilaricidal action in vitro LC50 and LC90 being 10 and 15 ng/ml for aqueous extract, 5 and 12 ng/ml for alcoholic extract.
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Abstract
Nine cases of frontonasal dysplasia were seen during an 8-year period. Seven were managed in the authors' institution, and the two adult relatives were referred to adult units. The age and sex distribution, the types of defects, and the family pedigree of an affected family are described. Management criteria were formulated according to the severity and other associated abnormalities.
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Brett F, Mowat A, Farquharson MA, McGill M, Hind C, Richmond J, Murray D, Khan NU, Foulis AK. The distribution of immunoreactive interferon-gamma-containing cells in normal human tissues. Immunol Suppl 1992; 77:515-9. [PMID: 1493923 PMCID: PMC1421654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
An immunohistochemical technique has been used to study the distribution of lymphocytes expressing interferon-gamma in normal adult tissues. The greatest concentrations of these cells were seen in mucosal sites exposed to a resident microflora. It is proposed that such organisms, by eliciting immune responses, provide the stimulus for the production of 'physiological' interferon-gamma. This in turn may act to preserve the 'tone' or readiness of the immune system.
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