Polycomb group protein-mediated histone modifications during cell differentiation.

Khan, Abdul Aziz,Lee, Andrew Jeoungun,Roh, Tae-Young Future Medicine 2015 Epigenomics Vol.7 No.1

<P>Polycomb group (PcG) proteins play an important role in the regulation of gene expression, especially genes encoding lineage-specific factors. Perturbations in PcG protein expression may trigger an unexpected developmental pathway, resulting in birth defects and developmental disabilities. Two Polycomb repressive complexes, PRC1 and PRC2, have been identified and are related with diverse cellular processes through histone modifications. Many developmental genes are trimethylated at histone H3 lysine 27 (H3K27me3) mediated by PRC2, which provides a binding site for PRC1. These processes contribute to chromatin compaction and transcriptional repression. In this review, we discuss about the complex formation of PcG proteins, the mechanism through which they are recruited to target sites and their functional roles in cell differentiation.</P>

Changes in Hematological Parameters with Pegylated Interferon in Chronic Hepatitis C Virus Infected Patients

Rehman, Aziz Ur,Ali, Farhad,Ali, Mashhood,Alam, Ibrar,Khan, Abdul Wali Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.5

The liver is one of the most common sites of cancer in the world, hepatocellular carcinoma (HCC) predominating. HCC is the sixth most common cancer and the third leading cause of cancer related death overall. Hepatitis C is a major risk factor and HCV is a rapid spreading virus which has become a problem globally, including in Pakistan. Interferon alpha therapy is used against HCV disease to regulate cell reproduction and to boost the immune system. In minute amounts interferon alpha is produced naturally by the immune system in HCV patients in response to hepatitis C virus and binds to receptors in the target cells and starts transcription of 20-30 genes due to which it develops an antiviral influence. Interferon is also administered artificially to overcome HCV disease and remove the biological effect of the virus from the infected site. The use of interferon or Peg-IFN plus Ribavirin treatment is also associated with adverse effects on body. For the current study, a convenient sample of 156 HCV positive patients of both males and females were taken. To collect blood CP and ALT, a reduction of level data and other important information were collected from the patients at regular intervals. Findings were 11.4 % in the red blood cells (RBC), 9.64 % in the total leukocyte count (WBC), 8.4 % in the hemoglobin levels (HB), 30.3 % in the platelet (Plt) count in both sexes. There was significant reduction in ALT levels due to Pegylated interferon plus ribavirin therapy. Hence strict haemotological monitoring of blood CP and ALT levels is necessary at regular intervals to reduce severe side effects which may lead to morbidity and mortality.

Measurement of Traffic-Related Air Pollution in Peshawar, Pakistan - A Pilot Study

Mohsin Khan,Mohammad Abdul Aziz Irfan,Najeeb Ullah 한국대기환경학회 2021 Asian Journal of Atmospheric Environment (AJAE) Vol.15 No.4

This pilot study measured Traffic-Related Air Pollution (TRAP) and calculated the corresponding Air Quality Index (AQI) in Peshawar. Using Libelium wireless sensors, the research measured outdoor TRAP and monitored indoor air quality for 48 days. The maximum outdoors daily mean concentration was 47 μg m-3 for PM1, 90 μg m-3 for PM2.5, 356 μg m-3 for PM10, 258 ppb for SO2, and 219 ppb for NO2, respectively. This corresponds to PM2.5 AQI of 158 (Unhealthy), PM10 AQI of 148 (Unhealthy for Sensitive Groups; USG), SO2 AQI of 181 (Unhealthy), and NO2 AQI of 123 (USG). The maximum daily average concentration for the indoor condition was 31 μg m-3 for PM1, 49 μg m-3 for PM2.5, 78 μg m-3 for PM10, 465 ppb for SO2, and 247 ppb for NO2, respectively. The corresponding AQI was 135 (USG) for PM2.5, 62 (Moderate) for PM10, 254 (Very Unhealthy) for SO2, and 129 (USG) for NO2. Data analysis shows that about 73% of the overall indoor AQI falls in the category of “USG”, while SO2 was the largest contributor to overall AQI. The study concludes that indoor AQI was slightly better than outdoor AQI because of the distance and height from the outdoor location. Moreover, Pakistan’s AQI for PM2.5 exceeds WHO’s 24-hours limit; however, it was relatively better by 23%, 65%, and 170% compared to China, India, and Bangladesh, respectively. In contrast, AQI for SO2 and NO2 was poor as compared to the same countries. The concentration and AQI for traffic-related air pollutants remain unhealthy and sometimes becomes hazardous, which means the sensitive groups are at greater risk.

Identification and Characterization of a Non-coding RNA at the Mouse Pcna Locus

이지연,김명희,Abdul Aziz Khan,민혜현,Xinnan Wang 한국분자세포생물학회 2012 Molecules and cells Vol.33 No.2

AK007836 encodes a noncoding RNA (ncRNA) consist-ing of 2 exons. Since AK007836 is located just upstream of Pcna and transcribed in the opposite direction to that of Pcna, we analyzed its expression pattern. Both ncRNA and Pcna expressions were detected in in vitro and in vivo cells, showing a positive correlation. A 177 bp region se-parating the first exons of Pcna and AK007836 has a bidirectional promoter activity. When the expression of ncRNA was reduced by siRNA, Pcna expression was also reduced in normal cells, but not in cancer cells. These results suggest that the ncRNA is divergently transcribed from the bidirectional promoter, positively regulating the neighboring protein-coding Pcna gene transcription, and this regulatory function is somehow disrupted in cancer cells.

Identification and characterization of a noncoding RNA at the mouse Pcna locus

Lee, Ji-Yeon,Khan, Abdul Aziz,Min, Hyehyun,Wang, Xinnan,Kim, Myoung Hee Springer-Verlag 2012 Molecules and cells Vol.33 No.2

Chromatin organization and transcriptional activation of Hox genes

Ji-Yeon Lee,Hyehyun Min,Xinnan Wang,Abdul Aziz Khan,Myoung Hee Kim 대한해부학회 2010 Anatomy & Cell Biology Vol.43 No.1

Spatially and temporally programmed expression of the Hox genes along the antero-posterior (A-P) axis is essential for correct pattern formation during embryonic development. An accumulating body of evidence indicates the pivotal role of spatial chromatin organization for the coordination of gene regulation. Recently, chromosome conformation capture (3C) technique has been developed and opened a new way to study chromosomal interactions in the nucleus. In this study, we describe 3C method we applied in F9 embryonic teratocarcinoma cells and demonstrate that the chromosomal interactions at Hox loci are successfully detected. Interestingly, at Hoxc loci, the abundance of intrachromosomal interactions with neighboring fragments was drastically decreased when the genes are expressed. These results indicate the possibility of the dynamic pattern of chromosomal interaction in association with the transcriptional regulation of Hox genes.

Assessing Efficiency of Handoff Techniques for Acquiring Maximum Throughput into WLAN

Mohsin Shaikha,Irfan Tunio,Baqir Zardari,Abdul Aziz,Ahmed Ali,Muhammad Abrar Khan International Journal of Computer ScienceNetwork S 2023 International journal of computer science and netw Vol.23 No.4

When the mobile device moves from the coverage of one access point to the radio coverage of another access point it needs to maintain its connection with the current access point before it successfully discovers the new access point, this process is known as handoff. During handoff the acceptable delay a voice over IP application can bear is of 50ms whereas the delay on medium access control layer is high enough that goes up to 350-500ms. This research provides a suitable methodology on medium access control layer of the IEEE 802.11 network. The medium access control layer comprises of three phases, namely discovery, reauthentication and re-association. The discovery phase on medium access control layer takes up to 90% of the total handoff latency. The objective is to effectively reduce the delay for discovery phase to ensure a seamless handoff. The research proposes a scheme that reduces the handoff latency effectively by scanning channels prior to the actual handoff process starts and scans only the neighboring access points. Further, the proposed scheme enables the mobile device to scan first the channel on which it is currently operating so that the mobile device has to perform minimum number of channel switches. The results show that the mobile device finds out the new potential access point prior to the handoff execution hence the delay during discovery of a new access point is minimized effectively.

Distributed Incremental Approximate Frequent Itemset Mining Using MapReduce

Mohsin Shaikh,Irfan Ali Tunio,Syed Muhammad Shehram Shah,Fareesa Khan Sohu,Abdul Aziz,Ahmad Ali International Journal of Computer ScienceNetwork S 2023 International journal of computer science and netw Vol.23 No.5

Traditional methods for datamining typically assume that the data is small, centralized, memory resident and static. But this assumption is no longer acceptable, because datasets are growing very fast hence becoming huge from time to time. There is fast growing need to manage data with efficient mining algorithms. In such a scenario it is inevitable to carry out data mining in a distributed environment and Frequent Itemset Mining (FIM) is no exception. Thus, the need of an efficient incremental mining algorithm arises. We propose the Distributed Incremental Approximate Frequent Itemset Mining (DIAFIM) which is an incremental FIM algorithm and works on the distributed parallel MapReduce environment. The key contribution of this research is devising an incremental mining algorithm that works on the distributed parallel MapReduce environment.

SREBP and MDT-15 protect <i>C. elegans</i> from glucose-induced accelerated aging by preventing accumulation of saturated fat

Lee, Dongyeop,Jeong, Dae-Eun,Son, Heehwa G.,Yamaoka, Yasuyo,Kim, Hyunmin,Seo, Keunhee,Khan, Abdul Aziz,Roh, Tae-Young,Moon, Dae Won,Lee, Youngsook,Lee, Seung-Jae V. Cold Spring Harbor Laboratory Press 2015 Genes & development Vol.29 No.23

<P>In this study, Lee et al. show that SREBP and MDT-15 prevent the life-shortening effects of a glucose-rich diet by regulating fat-converting processes in <I>C. elegans</I>. By using a genome-wide screen, they found that inhibition of SREBP or MDT-15 further accelerated aging in glucose-rich conditions, and up-regulation of SREBP or MDT-15 reversed accelerated aging.</P><P>Glucose-rich diets shorten the life spans of various organisms. However, the metabolic processes involved in this phenomenon remain unknown. Here, we show that sterol regulatory element-binding protein (SREBP) and mediator-15 (MDT-15) prevent the life-shortening effects of a glucose-rich diet by regulating fat-converting processes in <I>Caenorhabditis elegans</I>. Up-regulation of the SREBP/MDT-15 transcription factor complex was necessary and sufficient for alleviating the life-shortening effect of a glucose-rich diet. Glucose feeding induced key enzymes that convert saturated fatty acids (SFAs) to unsaturated fatty acids (UFAs), which are regulated by SREBP and MDT-15. Furthermore, SREBP/MDT-15 reduced the levels of SFAs and moderated glucose toxicity on life span. Our study may help to develop strategies against elevated blood glucose and free fatty acids, which cause glucolipotoxicity in diabetic patients.</P>