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Dive into the research topics where Sultan Asad is active.

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Featured researches published by Sultan Asad.


BMC Gastroenterology | 2011

A comparison of four fibrosis indexes in chronic HCV: Development of new fibrosis-cirrhosis index (FCI)

Waqar Ahmad; Bushra Ijaz; Fouzia T Javed; Sana Gull; Humaira Kausar; Muhammad Tahir Sarwar; Sultan Asad; Imran Shahid; Aleena Sumrin; Saba Khaliq; Shah Jahan; Asim Pervaiz; Sajida Hassan

BackgroundHepatitis C can lead to liver fibrosis and cirrhosis. We compared readily available non-invasive fibrosis indexes for the fibrosis progression discrimination to find a better combination of existing non-invasive markers.MethodsWe studied 157 HCV infected patients who underwent liver biopsy. In order to differentiate HCV fibrosis progression, readily available AAR, APRI, FI and FIB-4 serum indexes were tested in the patients. We derived a new fibrosis-cirrhosis index (FCI) comprised of ALP, bilirubin, serum albumin and platelet count. FCI = [(ALP × Bilirubin) / (Albumin × Platelet count)].ResultsAlready established serum indexes AAR, APRI, FI and FIB-4 were able to stage liver fibrosis with correlation coefficient indexes 0.130, 0.444, 0.578 and 0.494, respectively. Our new fibrosis cirrhosis index FCI significantly correlated with the histological fibrosis stages F0-F1, F2-F3 and F4 (r = 0.818, p < 0.05) with AUROCs 0.932 and 0.996, respectively. The sensitivity and PPV of FCI at a cutoff value < 0.130 for predicting fibrosis stage F0-F1 was 81% and 82%, respectively with AUROC 0.932. Corresponding value of FCI at a cutoff value ≥1.25 for the prediction of cirrhosis was 86% and 100%.ConclusionsThe fibrosis-cirrhosis index (FCI) accurately predicted fibrosis stages in HCV infected patients and seems more efficient than frequently used serum indexes.


Virology Journal | 2011

A brief review on molecular, genetic and imaging techniques for HCV fibrosis evaluation

Waqar Ahmad; Bushra Ijaz; Sana Gull; Sultan Asad; Saba Khaliq; Shah Jahan; Muhammad Tahir Sarwar; Humera Kausar; Aleena Sumrin; Imran Shahid; Sajida Hassan

BackgroundChronic HCV is one of the major causes of morbidity and mortality in the present day world. The assessment of disease progression not only provides useful information for diagnosis and therapeutic supervision judgment but also for monitoring disease. Different invasive and non invasive methods are applied to diagnose the disease from initial to end stage (mild fibrosis to cirrhosis). Although, liver biopsy is still considered as gold standard to identify liver histological stages, an assessment of the disease development based on non-invasive clinical findings is also emerging and this may replace the need of biopsy in near future. This review gives brief insight on non-invasive methods currently available for predicting liver fibrosis in HCV with their current pros and cons to make easier for a clinician to choose better marker to assess liver fibrosis in HCV infected patients.MethodsMore than 200 studies regarding invasive and noninvasive markers available for HCV liver disease diagnosis were thoroughly reviewed. We examined year wise results of these markers based on their sensitivity, specificity, PPV, NPV and AUROCs.ResultsWe found that in all non-invasive serum markers for HCV, FibroTest, Forns Index, Fibrometer and HepaScore have high five-year predictive value but with low AUROCs (0.60~0.85) and are not comparable to liver biopsy (AUROC = 0.97). Even though from its beginning, Fibroscan is proved to be best with high AUROCs (> 0.90) in all studies, no single noninvasive marker is able to differentiate all fibrosis stages from end stage cirrhosis. Meanwhile, specific genetic markers may not only discriminate fibrotic and cirrhotic liver but also differentiate individual fibrosis stages.ConclusionsThere is a need of marker which accurately determines the stage based on simplest routine laboratory test. Genetic marker in combination of imaging technique may be the better non invasive diagnostic method in future.


Virology Journal | 2011

Claudin-1 required for HCV virus entry has high potential for phosphorylation and O-glycosylation.

Waqar Ahmad; Khadija Shabbiri; Bushra Ijaz; Sultan Asad; Muhammad Tahir Sarwar; Sana Gull; Humera Kausar; Kiran Fouzia; Imran Shahid; Sajida Hassan

HCV is a leading cause of hepatocellular carcinoma and cirrhosis all over the world. Claudins belong to family of tight junctions proteins that are responsible for establishing barriers for controlling the flow of molecules around cells. For therapeutic strategies, regulation of viral entry into the host cells holds a lot of promise. During HCV infection claudin-1 is highly expressed in liver and believed to be associated with HCV virus entry after HCV binding with or without co-receptor CD81. The claudin-1 assembly with tight junctions is regulated by post translational modifications. During claudins assembly and disassembly with tight junctions, phosphorylation is required at C-terminal tail. In cellular proteins, interplay between phosphorylation and O-β-GlcNAc modification is believed to be functional switch, but it is very difficult to monitor these functional and vibrant changes in vivo. Netphos 2.0 and Disphos 1.3 programs were used for potential phosphorylation; NetPhosK 1.0 and KinasePhos for kinase prediction; and YinOYang 1.2 and OGPET to predict possible O-glycosylation sites. We also identified Yin Yang sites that may have potential for O-β-GlcNAc and phosphorylation interplay at same Ser/Thr residues. We for the first time proposed that alternate phosphorylation and O-β-GlcNAc modification on Ser 192, Ser 205, Ser 206; and Thr 191 may provide an on/off switch to regulate assembly of claudin-1 at tight junctions. In addition these phosphorylation sites may be targeted by novel chemotherapeutic agents to prevent phosphorylation lead by HCV viral entry complex.


Virology Journal | 2011

Association of laboratory parameters with viral factors in patients with hepatitis C.

Bushra Ijaz; Waqar Ahmad; Fouzia T Javed; Sana Gull; Muhammad Tahir Sarwar; Humera Kausar; Sultan Asad; Shah Jahan; Saba Khaliq; Imran Shahid; Aleena Sumrin; Sajida Hassan

Background and AimsHCV infection may lead to hepatic fibrosis. In this study, we tried to determine whether there is any correlation of HCV genotypes and viral load to the clinical parameters such as ALT, AST, ALP, bilirubin, Hb level, patients age and gender; and then correlated this association with disease progression in liver biopsy samples.MethodsIn cross-sectional and observational study, 6048 serum HCV RNA positive patients were chosen. The study consists of 53 months from March 2006 to September 2010. Patients were divided into three cohorts to validate our data. Statistical analysis and correlation of lab parameters with viral factors was determined by using SPSS version 16.ResultsThe most prevalent genotype was 3 (70.9%) followed by 1 (13.3%) and 4 (7.4%), collectively. During Univariate analysis, in all cohorts; serum bilirubin, ALP, ALT and AAR showed significant correlation with genotypes, however multivariate analysis showed that all genotypes except 4a have no association with host biochemical markers. Disease progression was also independent of all genotypes. Serum ALP, ALT, bilirubin and viremea levels were significantly elevated in patients with genotype 4a. Viral load showed negative association with serum bilirubin (r = -0.112, P = 0.000) and ALP levels (r = -0.098, P = 0.000). We observed positive correlation of ALP and bilirubin levels, while negative associations of viral load with HCV liver disease progression.ConclusionDisease progression seems independent of the genotypes. Relationship between ALP and bilirubin with viral load may be an attractive marker to guess disease progression in patients with hepatitis C.


Virology Journal | 2010

Inhibition of core gene of HCV 3a genotype using synthetic and vector derived siRNAs

Saba Khaliq; Shah Jahan; Bushra Ijaz; Waqar Ahmad; Sultan Asad; Asim Pervaiz; Baila Samreen; Mahwish Khan; Sajida Hassan

BackgroundHepatitis C virus (HCV) is a major causative agent of liver associated diseases throughout the world, with genotype 3a responsible for most of the cases in Pakistan. Due to the limited efficiency of current therapy, RNA interference (RNAi) a novel regulatory and powerful silencing approach for molecular therapeutics through a sequence-specific RNA degradation process represents an alternative option.ResultsThe current study was purposed to assess and explore the possibility of RNAi to silence the HCV-3a Core gene expression, which play complex role in regulation of cell growth and host genes expression essential for infectivity and disease progression. To identify the potent siRNA target sites, 5 small interfering RNAs (siRNAs) against Core gene were designed and invitro transcribed after consensus sequence analysis of different HCV-3a isolates. Antiviral effects of siRNAs showed upto 80% inhibition of Core gene expression by different siRNAs into Huh-7 cells as compared with Mock transfected and control siRNAs treated cells. For long lasting effect of siRNAs, vector based short hairpin siRNAs (shRNAs) were designed and tested against HCV-3a Core which resulted in a similar pattern of inhibition on RNA and protein expression of HCV Core as synthetic siRNAs. Furthermore, the efficacy of cell culture tested siRNA and shRNA, were evaluated for inhibition of HCV replication in HCV infected serum inoculated Huh-7 cells and a significant decrease in HCV viral copy number was observed.ConclusionsOur results support the possibility of using consensus siRNA and shRNA-based molecular therapy as a promising strategy in effective inhibition of HCV-3a genotype.


Asian Pacific Journal of Cancer Prevention | 2012

Five most common prognostically important fusion oncogenes are detected in the majority of Pakistani pediatric acute lymphoblastic leukemia patients and are strongly associated with disease biology and treatment outcome.

Tashfeen Awan; Zafar Iqbal; Aamer Aleem; Noreen Sabir; Muhammad Absar; Mahmood Rasool; Ammara H Tahir; Sulman Basit; Ahmad Mukhtar Khalid; Muhammad Farooq Sabar; Sultan Asad; Agha Shabbir Ali; Amer Mahmood; Muhammad Akram; Tariq Saeed; Arsalan Saleem; Danish Mohsin; Ijaz Hussain Shah; Muhammad Khalid; Muhammad Asif; Riazul Haq; Mudassar Iqbal; Tanveer Akhtar

BACKGROUND AND OBJECTIVES Acute lymphoblastic leukemia (ALL) is a complex genetic disease involving many fusion oncogenes (FO) having prognostic significance. The frequency of various FO can vary in different ethnic groups, with important implications for prognosis, drug selection and treatment outcome. METHOD We studied fusion oncogenes in 101 pediatric ALL patients using interphase FISH and RT-PCR, and their associations with clinical features and treatment outcome. RESULTS Five most common fusion genes i.e. BCR-ABL t (22; 9), TCF3-PBX1 (t 1; 19), ETV6-RUNX1 (t 12; 21), MLL-AF4 (t 4; 11) and SIL-TAL1 (del 1p32) were found in 89/101 (88.1%) patients. Frequency of BCR-ABL was 44.5% (45/101). BCR-ABL positive patients had a significantly lower survival (43.7±4.24 weeks) and higher white cell count as compared to others, except patients with MLL-AF4. The highest relapse-free survival was documented with ETV6-RUNX1 (14.2 months) followed closely by those cases in which no gene was detected (13.100). RFS with BCR-ABL, MLL-AF4, TCF3-PBX1 and SIL-TAL1 was less than 10 months (8.0, 3.6, 5.5 and 8.1 months, respectively). CONCLUSIONS This is the first study from Pakistan correlating molecular markers with disease biology and treatment outcome in pediatric ALL. It revealed the highest reported frequency of BCR-ABL FO in pediatric ALL, associated with poor overall survival. Our data indicate an immediate need for incorporation of tyrosine kinase inhibitors in the treatment of BCR-ABL+ pediatric ALL in this population and the development of facilities for stem cell transplantation.


Archives of Virology | 2011

Inhibition of hepatitis C virus genotype 3a by siRNAs targeting envelope genes

Saba Khaliq; Shah Jahan; Bushra Ijaz; Waqar Ahmad; Sultan Asad; Sajida Hassan

Hepatitis C virus (HCV) genotype 3a is considered a significant risk factor for the development of liver diseases and hepatocellular carcinoma for most of the cases in Pakistan. Because of the limited efficiency of the current therapy, RNA interference (RNAi), which results in sequence-specific degradation of HCV RNA, has potential as a powerful alternative molecular therapeutic approach. The envelope genes (E1 and E2) of HCV come in immediate contact with cells during infection and therefore might be a relevant target for new drug development. In the present study, the expression of E1 and E2 genes of HCV genotype 3a was dramatically reduced at both the mRNA and protein level using gene-specific small interfering RNAs (siRNA) when compared to mock-transfected and cells treated with control siRNAs. The potential of siRNAs to inhibit HCV-3a replication in serum-infected Huh-7 cells was also demonstrated by combined treatment of siRNAs against the E1 and E2 genes, which resulted in a significant decrease in HCV viral copy number. This clearly demonstrates that the RNAi-mediated silencing of HCV E1 and E2 is among the first of its type for the development of an effective siRNA-based therapeutic option against HCV-3a.


Asian Pacific Journal of Cancer Prevention | 2012

Prognostically Significant Fusion Oncogenes in Pakistani Patients with Adult Acute Lymphoblastic Leukemia and their Association with Disease Biology and Outcome

Noreen Sabir; Zafar Iqbal; Aamer Aleem; Tashfeen Awan; Sultan Asad; Ammara H Tahir; Muhammad Absar; Rana Mw; Sulman Basit; Muhammad Azhar Chishti; Muhammad Faiyaz; Ahmad Muktar Khalid; Muhammad Farooq Sabar; Sajjad Karim; Mahwish Khan; Baila Samreen; Muhammad Hassan Siddiqi; Saba Shahzadi; Sana Shahbaz; Amer Mahmood; Muhammad Akram; Tariq Saeed; Danish Mohsin; Ijaz Hussain Shah; Muhammad Khalid; Mudassar Iqbal; Tanveer Akhtar

BACKGROUND AND OBJECTIVES Chromosomal abnormalities play an important role in genesis of acute lymphoblastic leukemia (ALL) and have prognostic implications. Five major risk stratifying fusion genes in ALL are BCR-ABL, MLL-AF4, ETV6-RUNX11, E2A-PBX1 and SIL-TAL1. This work aimed to detect common chromosomal translocations and associated fusion oncogenes in adult ALL patients and study their relationship with clinical features and treatment outcome. METHODS We studied fusion oncogenes in 104 adult ALL patients using RT-PCR and interphase-FISH at diagnosis and their association with clinical characteristics and treatment outcome. RESULTS Five most common fusion genes i.e. BCR-ABL (t 9; 22), TCF3-PBX1 (t 1; 19), ETV6-RUNX1 (t 12; 21), MLL-AF4 (t 4; 11) and SIL-TAL1 (Del 1p32) were found in 82/104 (79%) patients. TCF3-PBX1 fusion gene was associated with lymphadenopathy, SIL-TAL positive patients had frequent organomegaly and usually presented with a platelets count of less than 50 x10(9)/l. Survival of patients with fusion gene ETV6-RUNX1 was better when compared to patients harboring other genes. MLL-AF4 and BCR-ABL positivity characterized a subset of adult ALL patients with aggressive clinical behaviour and a poor outcome. CONCLUSIONS This is the first study from Pakistan which investigated the frequency of 5 fusion oncogenes in adult ALL patients, and their association with clinical features, treatment response and outcome. Frequencies of some of the oncogenes were different from those reported elsewhere and they appear to be associated with distinct clinical characteristics and treatment outcome. This information will help in the prognostic stratification and risk adapted management of adult ALL patients.


Virology Journal | 2012

Development of persistent HCV genotype 3a infection cell culture model in huh-7 cell

Sultan Asad; Bushra Ijaz; Waqar Ahmad; Humera Kausar; Muhammad Tahir Sarwar; Sana Gull; Imran Shahid; Muhammad Kazim Khan; Sajida Hassan

BackgroundHepatitis C virus (HCV) is one of the major health concerns globally, with genotype 3a as the most prevalent in Pakistan. Lack of efficient HCV genotype 3a small animal models as well as genomic replicons has hampered the complete understanding of its life cycle, pathogenesis and therapeutic options. In this study we aimed to develop a persistent HCV genotype 3a infectious cell culture model.MethodsWe inoculated Huh-7 cells with HCV genotype 3a serum. Cells and media supernatant were collected at different time periods up to 40th day post infection. Culture media supernatant was also collected to find out its ability to infect naive Huh-7 cells.ResultsHCV replication was confirmed at both RNA and protein level through Real Time RCR and western blot using HCV core as marker. In order to validate the persistence of our model for HCV genotype 3a replication we inhibited the HCV replication through core specific siRNAs. The HCV RNA was detected intracellularly from the day one post infection up till 40th day, while HCV core protein was detected from the second day up to 40th day consistently. In culture media supernatant HCV RNA was also actively detected conferring its ability to infect the naive Huh-7 cells. Furthermore, core specific siRNA showed significant inhibition at 24th hour post transfection both at RNA and protein level with progressive increase in the expression of core gene after 3rd day. It clearly depicts that the Huh-7 successfully retained the HCV replication after degradation of siRNA.ConclusionFinally, we report that our persistent infection cell culture model consistently replicate HCV genotype 3a for more than 1 month.


Virology Journal | 2011

NS4A protein as a marker of HCV history suggests that different HCV genotypes originally evolved from genotype 1b

Muhammad Tahir Sarwar; Humera Kausar; Bushra Ijaz; Waqar Ahmad; Muhammad Ansar; Aleena Sumrin; Usman Ali Ashfaq; Sultan Asad; Sana Gull; Imran Shahid; Sajida Hassan

BackgroundThe 9.6 kb long RNA genome of Hepatitis C virus (HCV) is under the control of RNA dependent RNA polymerase, an error-prone enzyme, for its transcription and replication. A high rate of mutation has been found to be associated with RNA viruses like HCV. Based on genetic variability, HCV has been classified into 6 different major genotypes and 11 different subtypes. However this classification system does not provide significant information about the origin of the virus, primarily due to high mutation rate at nucleotide level. HCV genome codes for a single polyprotein of about 3011 amino acids which is processed into structural and non-structural proteins inside host cell by viral and cellular proteases.ResultsWe have identified a conserved NS4A protein sequence for HCV genotype 3a reported from four different continents of the world i.e. Europe, America, Australia and Asia. We investigated 346 sequences and compared amino acid composition of NS4A protein of different HCV genotypes through Multiple Sequence Alignment and observed amino acid substitutions C22, V29, V30, V38, Q46 and Q47 in NS4A protein of genotype 1b. Furthermore, we observed C22 and V30 as more consistent members of NS4A protein of genotype 1a. Similarly Q46 and Q47 in genotype 5, V29, V30, Q46 and Q47 in genotype 4, C22, Q46 and Q47 in genotype 6, C22, V38, Q46 and Q47 in genotype 3 and C22 in genotype 2 as more consistent members of NS4A protein of these genotypes. So the different amino acids that were introduced as substitutions in NS4A protein of genotype 1 subtype 1b have been retained as consistent members of the NS4A protein of other known genotypes.ConclusionThese observations indicate that NS4A protein of different HCV genotypes originally evolved from NS4A protein of genotype 1 subtype 1b, which in turn indicate that HCV genotype 1 subtype 1b established itself earlier in human population and all other known genotypes evolved later as a result of mutations in HCV genotype 1b. These results were further confirmed through phylogenetic analysis by constructing phylogenetic tree using NS4A protein as a phylogenetic marker.

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Bushra Ijaz

University of the Punjab

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Sajida Hassan

University of the Punjab

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Waqar Ahmad

University of the Punjab

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Sana Gull

University of the Punjab

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Humera Kausar

University of the Punjab

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Imran Shahid

University of the Punjab

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Saba Khaliq

University of Health Sciences Lahore

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Shah Jahan

University of Health Sciences Lahore

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Aleena Sumrin

University of the Punjab

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