Skin lesions in hospitalized cases of dengue Fever.

PubMed

Saleem, Khawer; Shaikh, Irfan

2008-10-01

To determine the frequency and types of skin lesions in cases of dengue fever in patients admitted in three hospitals of Karachi. Case series. Three tertiary care hospitals of Karachi, from November 2006 to February 2007. One hundred patients of dengue fever with positive anti-dengue Immunoglobulin M (IgM) serology were included in the study. The admitted patients in PNS Shifa Hospital, Jinnah Postgraduate Medical Centre (JPMC) and Civil Hospital, Karachi were selected for the study. Presenting features were noted. The patients were physically examined for the presence of skin and mucosal lesions and findings were recorded. Total and Differential Leukocyte Count (TLC and DLC), platelet count and Liver Function Tests (LFTs) were done in all the patients. All the patients had low leukocyte and low platelet counts. The common presenting symptoms were high-grade fever with or without rigors, headache, body aches, backache, vomiting, sore throat with cough and generalized weakness (seen in 86% patients). The uncommon presenting features were diarrhea, abdominal pain, bleeding from gums and nosebleeds (seen in 14% patients). Sixty-eight (68%) patients had skin lesions. The most common skin presentation was generalized macular blanchable erythema involving trunk and limbs, seen in 44 (65%) cases. Discrete petechial lesions were seen on various body areas in 24 (35%) cases. Palmer erythema was seen in 20 (30%) patients. Generalized itching was seen in 16 (23%) cases. Isolated itching of palms and soles was seen in 20 (30%) cases. Twenty-eight (28%) patients had deranged LFTs. Out of those, 4 patients had raised serum bilirubin level whereas rest of the 24 had raised ALT. Dengue fever commonly presents with specific skin lesions. The skin lesions can be a clue to the diagnosis in difficult cases.

Checkpoint kinase 1 expression is an adverse prognostic marker and therapeutic target in MYC-driven medulloblastoma

PubMed Central

Shah, Monil; Mulcahy Levy, Jean M.; Griesinger, Andrea M.; Alimova, Irina; Harris, Peter S.; Birks, Diane K.; Donson, Andrew M.; Davidson, Nathan; Remke, Marc; Taylor, Michael D.; Handler, Michael H.; Foreman, Nicholas K.; Venkataraman, Sujatha; Vibhakar, Rajeev

2016-01-01

Checkpoint kinase 1 (CHK1) is an integral component of the cell cycle as well as the DNA Damage Response (DDR) pathway. Previous work has demonstrated the effectiveness of inhibiting CHK1 with small-molecule inhibitors, but the role of CHK1 mediated DDR in medulloblastoma is unknown. CHK1, both at the mRNA and protein level, is highly expressed in medulloblastoma and elevated CHK1 expression in Group3 medulloblastoma is an adverse prognostic marker. CHK1 inhibition with the small-molecule drug AZD7762, results in decreased cell growth, increased DNA damage and cell apoptosis. Furthermore, AZD7762 acts in synergy with cisplatin in reducing cell proliferation in medulloblastoma. Similar phenotypic changes were observed with another CHK1 inhibitor, PF477736, as well as genetic knockdown using siRNA against CHK1. Treatments with small-molecule inhibitors of CHK1 profoundly modulated the expression of both upstream and downstream target proteins within the CHK1 signaling pathways. This suggests the presence of a feedback loop in activating CHK1. Overall, our results demonstrate that small-molecule inhibition of CHK1 in combination with, cisplatin, is more advantageous than either treatment alone, especially for Group 3 medulloblastoma, and therefore this combined therapeutic approach serves as an avenue for further investigation. PMID:27449089

Checkpoint kinase 1 expression is an adverse prognostic marker and therapeutic target in MYC-driven medulloblastoma.

PubMed

Prince, Eric W; Balakrishnan, Ilango; Shah, Monil; Mulcahy Levy, Jean M; Griesinger, Andrea M; Alimova, Irina; Harris, Peter S; Birks, Diane K; Donson, Andrew M; Davidson, Nathan; Remke, Marc; Taylor, Michael D; Handler, Michael H; Foreman, Nicholas K; Venkataraman, Sujatha; Vibhakar, Rajeev

2016-08-16

Checkpoint kinase 1 (CHK1) is an integral component of the cell cycle as well as the DNA Damage Response (DDR) pathway. Previous work has demonstrated the effectiveness of inhibiting CHK1 with small-molecule inhibitors, but the role of CHK1 mediated DDR in medulloblastoma is unknown. CHK1, both at the mRNA and protein level, is highly expressed in medulloblastoma and elevated CHK1 expression in Group3 medulloblastoma is an adverse prognostic marker. CHK1 inhibition with the small-molecule drug AZD7762, results in decreased cell growth, increased DNA damage and cell apoptosis. Furthermore, AZD7762 acts in synergy with cisplatin in reducing cell proliferation in medulloblastoma. Similar phenotypic changes were observed with another CHK1 inhibitor, PF477736, as well as genetic knockdown using siRNA against CHK1. Treatments with small-molecule inhibitors of CHK1 profoundly modulated the expression of both upstream and downstream target proteins within the CHK1 signaling pathways. This suggests the presence of a feedback loop in activating CHK1. Overall, our results demonstrate that small-molecule inhibition of CHK1 in combination with, cisplatin, is more advantageous than either treatment alone, especially for Group 3 medulloblastoma, and therefore this combined therapeutic approach serves as an avenue for further investigation.

THE FORK AND THE KINASE: A DNA REPLICATION TALE FROM A CHK1 PERSPECTIVE

PubMed Central

González Besteiro, Marina A.; Gottifredi, Vanesa

2014-01-01

Replication fork progression is being continuously hampered by exogenously introduced and naturally occurring DNA lesions and other physical obstacles. The checkpoint kinase 1 (Chk1) is activated at replication forks that encounter damaged-DNA. Chk1 inhibits the initiation of new replication factories and stimulates the firing of dormant origins (those in the vicinity of stalled forks). Chk1 also avoids fork collapse into DSBs (double strand breaks) and promotes fork elongation. At the molecular level, the current model considers stalled forks as the site of Chk1 activation and the nucleoplasm as the location where Chk1 phosphorylates target proteins. This model certainly serves to explain how Chk1 modulates origin firing, but how Chk1 controls the fate of stalled forks is less clear. Interestingly, recent reports demonstrating that Chk1 phosphorylates chromatin-bound proteins and even holds kinase-independent functions might shed light on how Chk1 contributes to the elongation of damaged DNA. Such findings unveil a puzzling connection between Chk1 and DNA-lesion bypass, which might be central to promoting fork elongation and checkpoint attenuation. In summary, the multifaceted and versatile functions of Chk1 at ongoing forks and replication origins determine the extent and quality of the cellular response to replication stress. PMID:25795119

Cellular Inhibition of Checkpoint Kinase 2 (Chk2) and Potentiation of Camptothecins and Radiation by the Novel Chk2 Inhibitor PV1019 [7-Nitro-1H-indole-2-carboxylic acid {4-[1-(guanidinohydrazone)-ethyl]-phenyl}-amide

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jobson, Andrew G.; Lountos, George T.; Lorenzi, Philip L.

2010-04-05

Chk2 is a checkpoint kinase involved in the ataxia telangiectasia mutated pathway, which is activated by genomic instability and DNA damage, leading to either cell death (apoptosis) or cell cycle arrest. Chk2 provides an unexplored therapeutic target against cancer cells. We recently reported 4,4'-diacetyldiphenylurea-bis(guanylhydrazone) (NSC 109555) as a novel chemotype Chk2 inhibitor. We have now synthesized a derivative of NSC 109555, PV1019 (NSC 744039) [7-nitro-1H-indole-2-carboxylic acid {l_brace}4-[1-(guanidinohydrazone)-ethyl]-phenyl{r_brace}-amide], which is a selective submicromolar inhibitor of Chk2 in vitro. The cocrystal structure of PV1019 bound in the ATP binding pocket of Chk2 confirmed enzymatic/biochemical observations that PV1019 acts as a competitive inhibitormore » of Chk2 with respect to ATP. PV1019 was found to inhibit Chk2 in cells. It inhibits Chk2 autophosphorylation (which represents the cellular kinase activation of Chk2), Cdc25C phosphorylation, and HDMX degradation in response to DNA damage. PV1019 also protects normal mouse thymocytes against ionizing radiation-induced apoptosis, and it shows synergistic antiproliferative activity with topotecan, camptothecin, and radiation in human tumor cell lines. We also show that PV1019 and Chk2 small interfering RNAs can exert antiproliferative activity themselves in the cancer cells with high Chk2 expression in the NCI-60 screen. These data indicate that PV1019 is a potent and selective inhibitor of Chk2 with chemotherapeutic and radiosensitization potential.« less

The fork and the kinase: a DNA replication tale from a CHK1 perspective.

PubMed

González Besteiro, Marina A; Gottifredi, Vanesa

2015-01-01

Replication fork progression is being continuously hampered by exogenously introduced and naturally occurring DNA lesions and other physical obstacles. Checkpoint kinase 1 (Chk1) is activated at replication forks that encounter damaged DNA. Subsequently, Chk1 inhibits the initiation of new replication factories and stimulates the firing of dormant origins (those in the vicinity of stalled forks). Chk1 also avoids fork collapse into DSBs (double strand breaks) and promotes fork elongation. At the molecular level, the current model considers stalled forks as the site of Chk1 activation and the nucleoplasm as the location where Chk1 phosphorylates target proteins. This model certainly serves to explain how Chk1 modulates origin firing, but how Chk1 controls the fate of stalled forks is less clear. Interestingly, recent reports demonstrating that Chk1 phosphorylates chromatin-bound proteins and even holds kinase-independent functions might shed light on how Chk1 contributes to the elongation of damaged DNA. Indeed, such findings have unveiled a puzzling connection between Chk1 and DNA lesion bypass, which might be central to promoting fork elongation and checkpoint attenuation. In summary, Chk1 is a multifaceted and versatile signaling factor that acts at ongoing forks and replication origins to determine the extent and quality of the cellular response to replication stress. Copyright © 2014 Elsevier B.V. All rights reserved.

Poly(ADP-ribose) binding to Chk1 at stalled replication forks is required for S-phase checkpoint activation

NASA Astrophysics Data System (ADS)

Min, Wookee; Bruhn, Christopher; Grigaravicius, Paulius; Zhou, Zhong-Wei; Li, Fu; Krüger, Anja; Siddeek, Bénazir; Greulich, Karl-Otto; Popp, Oliver; Meisezahl, Chris; Calkhoven, Cornelis F.; Bürkle, Alexander; Xu, Xingzhi; Wang, Zhao-Qi

2013-12-01

Damaged replication forks activate poly(ADP-ribose) polymerase 1 (PARP1), which catalyses poly(ADP-ribose) (PAR) formation; however, how PARP1 or poly(ADP-ribosyl)ation is involved in the S-phase checkpoint is unknown. Here we show that PAR, supplied by PARP1, interacts with Chk1 via a novel PAR-binding regulatory (PbR) motif in Chk1, independent of ATR and its activity. iPOND studies reveal that Chk1 associates readily with the unperturbed replication fork and that PAR is required for efficient retention of Chk1 and phosphorylated Chk1 at the fork. A PbR mutation, which disrupts PAR binding, but not the interaction with its partners Claspin or BRCA1, impairs Chk1 and the S-phase checkpoint activation, and mirrors Chk1 knockdown-induced hypersensitivity to fork poisoning. We find that long chains, but not short chains, of PAR stimulate Chk1 kinase activity. Collectively, we disclose a previously unrecognized mechanism of the S-phase checkpoint by PAR metabolism that modulates Chk1 activity at the replication fork.

Nuclear Chk1 prevents premature mitotic entry.

PubMed

Matsuyama, Makoto; Goto, Hidemasa; Kasahara, Kousuke; Kawakami, Yoshitaka; Nakanishi, Makoto; Kiyono, Tohru; Goshima, Naoki; Inagaki, Masaki

2011-07-01

Chk1 inhibits the premature activation of the cyclin-B1-Cdk1. However, it remains controversial whether Chk1 inhibits Cdk1 in the centrosome or in the nucleus before the G2-M transition. In this study, we examined the specificity of the mouse monoclonal anti-Chk1 antibody DCS-310, with which the centrosome was stained. Conditional Chk1 knockout in mouse embryonic fibroblasts reduced nuclear but not centrosomal staining with DCS-310. In Chk1(+/myc) human colon adenocarcinoma (DLD-1) cells, Chk1 was detected in the nucleus but not in the centrosome using an anti-Myc antibody. Through the combination of protein array and RNAi technologies, we identified Ccdc-151 as a protein that crossreacted with DCS-310 on the centrosome. Mitotic entry was delayed by expression of the Chk1 mutant that localized in the nucleus, although forced immobilization of Chk1 to the centrosome had little impact on the timing of mitotic entry. These results suggest that nuclear but not centrosomal Chk1 contributes to correct timing of mitotic entry.

Presentations and Outcome of Thyroiditis from a Tertiary Care Hospital of Karachi.

PubMed

Mahar, Saeed Ahmed; Shahid, Muhammad; Sarfaraz, Aqiba; Shaikh, Zuhaib-u-Ddin; Shaikh, Shiraz; Shahid, Nadia

2015-10-01

To assess the clinical presentations and short-term outcomes of patients with thyroiditis presenting to a tertiary care hospital in Karachi, Pakistan. Case series. Department of Endocrinology, Liaquat National Hospital, Karachi, from June 2014 to February 2015. Patients between 18 and 70 years of age with acute onset of thyroiditis confirmed on thyroid scan or clinical judgment presenting to the outpatient services were included in the study. Pregnant females, psychiatric patients and patients having other chronic illnesses were excluded from the study. A total of 26 patients with thyroiditis attended the endocrine clinic. Mean age of patients was 41.2 ± 11.12 years. There were 18 (69.2%) females. Clinical presentations were fever (65.4%), tender neck (23.1%), goiter (19.2%), localized tenderness in neck and palpable lymph nodes (26.9%). Major symptoms reported were: sore throat (69.2%), weight loss (38.5%), upper respiratory tract infection, thyroid pain, tremor, sweating and fever of unknown origin in 26.9% cases. All the patients had raised Erythrocyte Sedimentation Rate (ESR). Low Thyroid Stimulating Hormone (TSH) < 0.4 mlU/L was seen in 88.5% and 57.7% had raised Free T4 > 1.8 ng/dL. Complete recovery was seen in 88.5% patients while 11.5% had early hypothyroidism. Fever and sore throat were the main presenting features of thyroiditis patients. ESR was raised in all patients. A majority of patients had complete recovery with appropriate management; however, few cases developed hypothyroidism.

Pattern of external injuries sustained during bomb blast attacks in Karachi, Pakistan from 2000 to 2007.

PubMed

Surani, Arif Anwar; Ali, Salman; Surani, Asif; Zahid, Sohaib; Shoukat, Akber; Varon, Joseph; Surani, Salim

2015-07-01

To evaluate patterns of external injury resulting from bomb blasts in Karachi, and compare the injury profile resulting from explosions in open versus semi-confined blast environments. The retrospective, cross-sectional study was conducted in Karachi and comprised relevant data from January 2000 to October 2007. Casualty medical records and medico-legal certificates of the victims presented to three large public-sector hospitals were evaluated using a self-designed proforma. SPSS 17 was used for statistical analysis. Of the 1146 victims, data of 481(42%) represented the final study sample. Of these, 306(63.6%) were injured in open spaces and 175(36.4%) in semi-confined spaces. Of the 896 recorded injuries, lacerations were encountered as external injury in 427(47.7%) cases, followed by penetrating wounds in 137(15.3%). Lower and upper extremities were injured in 348(38.8%) and 170(19%) victims respectively. Open and semi-confined blast environments produced specific injury pattern and profile (p<0.001). External injuries sustained during bomb blast attacks in Karachi demonstrated specific injury patterns and profiles. Further studies are required to account for internal injuries and classification of injuries based on standardised scoring systems.

Direct association of Csk homologous kinase (CHK) with the diphosphorylated site Tyr568/570 of the activated c-KIT in megakaryocytes.

PubMed

Price, D J; Rivnay, B; Fu, Y; Jiang, S; Avraham, S; Avraham, H

1997-02-28

The Csk homologous kinase (CHK), formerly MATK, has previously been shown to bind to activated c-KIT. In this report, we characterize the binding of SH2(CHK) to specific phosphotyrosine sites on the c-KIT protein sequence. Phosphopeptide inhibition of the in vitro interaction of SH2(CHK)-glutathione S-transferase fusion protein/c-KIT from SCF/KL-treated Mo7e megakaryocytic cells indicated that two sites on c-KIT were able to bind SH2(CHK). These sites were the Tyr568/570 diphosphorylated sequence and the monophosphorylated Tyr721 sequence. To confirm this, we precipitated native CHK from cellular extracts using phosphorylated peptides linked to Affi-Gel 15. In addition, purified SH2(CHK)-glutathione S-transferase fusion protein was precipitated with the same peptide beads. All of the peptide bead-binding studies were consistent with the direct binding of SH2(CHK) to phosphorylated Tyr568/570 and Tyr721 sites. Binding of FYN and SHC to the diphosphorylated Tyr568/570 site was observed, while binding of Csk to this site was not observed. The SH2(CHK) binding to the two sites is direct and not through phosphorylated intermediates such as FYN or SHC. Site-directed mutagenesis of the full-length c-KIT cDNA followed by transient transfection indicated that only the Tyr568/570, and not the Tyr721, is able to bind SH2(CHK). This indicates that CHK binds to the same site on c-KIT to which FYN binds, possibly bringing the two into proximity on associated c-KIT subunits and leading to the down-regulation of FYN by CHK.

Identification of novel inhibitors of human Chk1 using pharmacophore-based virtual screening and their evaluation as potential anti-cancer agents

NASA Astrophysics Data System (ADS)

Kumar, Vikash; Khan, Saman; Gupta, Priyanka; Rastogi, Namrata; Mishra, Durga Prasad; Ahmed, Shakil; Siddiqi, Mohammad Imran

2014-12-01

Kinases are one of the major players in cancer development and progression. Serine threonine kinases such as human checkpoint kinase-1 (Chk1), Mek1 and cyclin-dependent kinases have been identified as promising targets for cancer treatment. Chk1 is an important kinase with vital role in cell cycle arrest and many potent inhibitors targeted to Chk1 have been reported and few are currently in clinical trials. Considering the emerging importance of Chk1 inhibitors in cancer treatment there is a need to widen the chemical space of Chk1 inhibitors. In this study, we are reporting an integrated in silico approach to identify novel competitive Chk1 inhibitors. A 4-features pharmacophore model was derived from a co-crystallized structure of known potent Chk1 inhibitor and subjected to screen Maybridge compound library. Hits obtained from the screening were docked into the Chk1 active site and filtered on the basis of docking score and the number of pharmacophoric features showing conserved interaction within the active site of Chk1. Further, five compounds from the top ranking hits were subjected to in vitro evaluation as Chk1 inhibitor. After the kinase assay, four compounds were found to be active against human Chk1 (IC50 range from 4.2 to 12.5 µM). Subsequent study using the cdc25-22 mutant yeast cells revealed that one of compound (SPB07479; IC50 = 4.24 µM) promoted the formation of multinucleated cells, therefore overriding the cell cycle checkpoint. Validation studies using normal and human cancer cell lines, indicated that SPB07479 significantly inhibited proliferation of cervical cancer cells as a single agent and chemosensitized glioma and pancreatic cancer cell lines to standard chemotherapy while sparing normal cells. Additionally SPB07479 did not show significant cytotoxicity in normal cells. In conclusion we report that SPB07479 appear promising for further development of Chk1 inhibitors. This study also highlights the role of conserved water molecules in the active site of Chk1 for the successful identification of novel inhibitors.

Aven-mediated checkpoint kinase control regulates proliferation and resistance to chemotherapy in conventional osteosarcoma.

PubMed

Baranski, Zuzanna; Booij, Tijmen H; Cleton-Jansen, Anne-Marie; Price, Leo S; van de Water, Bob; Bovée, Judith V M G; Hogendoorn, Pancras C W; Danen, Erik H J

2015-07-01

Conventional high-grade osteosarcoma is the most common primary bone sarcoma, with relatively high incidence in young people. In this study we found that expression of Aven correlates inversely with metastasis-free survival in osteosarcoma patients and is increased in metastases compared to primary tumours. Aven is an adaptor protein that has been implicated in anti-apoptotic signalling and serves as an oncoprotein in acute lymphoblastic leukaemia. In osteosarcoma cells, silencing Aven triggered G2 cell-cycle arrest; Chk1 protein levels were attenuated and ATR-Chk1 DNA damage response signalling in response to chemotherapy was abolished in Aven-depleted osteosarcoma cells, while ATM, Chk2 and p53 activation remained intact. Osteosarcoma is notoriously difficult to treat with standard chemotherapy, and we examined whether pharmacological inhibition of the Aven-controlled ATR-Chk1 response could sensitize osteosarcoma cells to genotoxic compounds. Indeed, pharmacological inhibitors targeting Chk1/Chk2 or those selective for Chk1 synergized with standard chemotherapy in 2D cultures. Likewise, in 3D extracellular matrix-embedded cultures, Chk1 inhibition led to effective sensitization to chemotherapy. Together, these findings implicate Aven in ATR-Chk1 signalling and point towards Chk1 inhibition as a strategy to sensitize human osteosarcomas to chemotherapy. Copyright © 2015 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Audit of custodial deaths in Karachi--an autopsy-based study.

PubMed

Mirza, Farhat Hussain; Memon, Akhtar Amin; Adil, Syeda Ezz-e-Rukhshan; Paryar, Hamid Ali

2012-08-01

To assess the causes and manner of custodial deaths in Karachi, and to determine the factor of negligence on the part of the custodians behind such deaths. The cross-sectional study involved the deaths in custody undergoing autopsy at Civil Hospital, Karachi, from January 2005 to December 2010. Autopsy was followed by histological examination, X-ray or CT scan wherever required. A proforma was also filled as per the standard autopsy protocol. There were 61 custodial deaths in Karachi during the six-year study period which met the inclusion criterion. There were 58 (95.1%) males and 3 (9.4%) females. Natural causes accounted for a majority of deaths (n = 36; 59%), the most common disease being coronary artery disease (n = 13; 21.3%). Unnatural causes accounted for 25 (41%) deaths, comprising 13 (21.3%) homicidal, 7 (11.5%) suicidal and 5 (8.2%) accidental. Deaths were more frequent in the age group ranging from 30-39 years (34.4%), while the overall age-range was from 19 to 75 years. Measures need to be taken to provide a wholesome environment for the prisoners. Code of conduct for the prisoners should be followed and judicial procedures shall be conducted at a quick pace. Torture should be avoided under all circumstances, and proper vigilance shall be kept to prompt suicidal deaths.

Multi-lobulation of the nucleus in prolonged S phase by nuclear expression of Chk tyrosine kinase.

PubMed

Nakayama, Yuji; Yamaguchi, Naoto

2005-04-01

Chk tyrosine kinase phosphorylates Src-family tyrosine kinases and suppresses their kinase activity. We recently showed that Chk localizes to the nucleus as well as the cytoplasm and inhibits cell proliferation. To investigate the role of nuclear Chk in proliferation, various Chk mutants were constructed and expressed. Nuclear localization of Chk-induced dynamic multi-lobulation of the nucleus and prolonged S phase of the cell cycle. The N-terminal domain of Chk and a portion of its kinase domain but not the kinase activity were responsible for induction of the multi-lobulation. Cell sorting analysis revealed that nuclear multi-lobulated cells were enriched in late S phase. Multi-lobulated nuclei were surrounded with lamin B1 that was particularly concentrated in concave regions of the nuclei. Furthermore, treatment with nocodazole or taxol disrupted multi-lobulation of the nucleus. These results suggest that nuclear multi-lobulation in late S phase, which is dependent on polymerization and depolymerization of microtubules, may be involved in nuclear Chk-induced inhibition of proliferation.

Human T-cell leukemia virus type 1 Tax interacts with Chk1 and attenuates DNA-damage induced G2 arrest mediated by Chk1.

PubMed

Park, Hyeon Ung; Jeong, Jae-Hoon; Chung, Jay H; Brady, John N

2004-06-24

Checkpoint kinase 1 (Chk1) mediates diverse cellular responses to genotoxic stress, regulating the network of genome-surveillance pathways that coordinate cell cycle progression with DNA repair. Chk1 is essential for mammalian development and viability, and has been shown to be important for both S and G(2) checkpoints. We now present evidence that the HTLV-1 Tax protein interacts directly with Chk1 and impairs its kinase activities in vitro and in vivo. The direct and physical interaction of Chk1 and Tax was observed in HTLV-1-infected T cells (C81, HuT 102 and MT-2) and transfected fibroblasts (293 T) by coimmunoprecipitation and by in vitro GST pull-down assays. Interestingly, Tax inhibited the kinase activity of Chk1 protein in in vitro and in vivo kinase assays. Consistent with these results, Tax inhibited the phosphorylation-dependent degradation of Cdc25A and G(2) arrest in response to gamma-irradiation (IR) in a dose-dependent manner in vivo. The G(2) arrest did not require Chk2 or p53. These studies provide the first example of a viral transforming protein targeting Chk1 and provide important insights into checkpoint pathway regulation.

Crystal structure of checkpoint kinase 2 in complex with NSC 109555, a potent and selective inhibitor

PubMed Central

Lountos, George T; Tropea, Joseph E; Zhang, Di; Jobson, Andrew G; Pommier, Yves; Shoemaker, Robert H; Waugh, David S

2009-01-01

Checkpoint kinase 2 (Chk2), a ser/thr kinase involved in the ATM-Chk2 checkpoint pathway, is activated by genomic instability and DNA damage and results in either arrest of the cell cycle to allow DNA repair to occur or apoptosis if the DNA damage is severe. Drugs that specifically target Chk2 could be beneficial when administered in combination with current DNA-damaging agents used in cancer therapy. Recently, a novel inhibitor of Chk2, NSC 109555, was identified that exhibited high potency (IC50 = 240 nM) and selectivity. This compound represents a new chemotype and lead for the development of novel Chk2 inhibitors that could be used as therapeutic agents for the treatment of cancer. To facilitate the discovery of new analogs of NSC 109555 with even greater potency and selectivity, we have solved the crystal structure of this inhibitor in complex with the catalytic domain of Chk2. The structure confirms that the compound is an ATP-competitive inhibitor, as the electron density clearly reveals that it occupies the ATP-binding pocket. However, the mode of inhibition differs from that of the previously studied structure of Chk2 in complex with debromohymenialdisine, a compound that inhibits both Chk1 and Chk2. A unique hydrophobic pocket in Chk2, located very close to the bound inhibitor, presents an opportunity for the rational design of compounds with higher binding affinity and greater selectivity. PMID:19177354

Characterizing the Impact of Extreme Heat on Mortality, Karachi, Pakistan, June 2015.

PubMed

Ghumman, Usman; Horney, Jennifer

2016-06-01

Introduction Karachi, Pakistan was affected by a heat wave in June 2015 during the Muslim holy month of Ramadan. Many media reports attributed the excess deaths in part to the practice of daylight fasting during Ramadan. As much of the published research reports on heat-related mortality in Europe and the United States, an exploration of the effects of extreme heat on residents of a South Asian mega-city address a gap in current disaster research. Hypothesis/Problem This report investigated potential risk factors for excess mortality associated with the June 2015 heat wave in Karachi, Pakistan. Data were obtained through manual review of death certificates at public hospitals and private clinics in Karachi, Pakistan, conducted from July 1 through July 31, 2015 by a trained physician. Demographic data for any deaths with a primary cause of death of heat-related illness were recorded in Microsoft Excel (Microsoft Corp.; Redmond, Washington USA). EpiSheet (2012; Rothman. Modern Epidemiology. Lippincott Williams & Wilkins; Philadelphia, Pennsylvania USA) was used to calculate risk differences (RD), rate ratios (RR), and 95% confidence intervals (95% CI). Overall, residents of Karachi were approximately 17 times as likely to die of a heat-related cause of death during June 2015 (RR=17.68; 95% CI, 13.87-22.53) when compared with the reference period of June 2014. Residents with a monthly income lower than 20,000 Pakistani Rupees (US $196; RD=0.03; 95% CI, 0.01-0.05) and those with less than a fifth grade education (RD=0.03; 95% CI, 0.00-0.05) were at significantly higher risk of death during the 2015 heat wave compared to the reference period. Fasting during Ramadan was not a significant risk factor for mortality from heat-related causes during the Karachi heat wave of June 2015. A large number of excess deaths were reported across all demographic groups, which due to the burden of record keeping in an under-resourced health system during a public health emergency, are almost certainly an underestimate. Ghumman U , Horney J . Characterizing the impact of extreme heat on mortality, Karachi, Pakistan, June 2015. Prehosp Disaster Med. 2016;31(3):263-266.

Functional diversity of Csk, Chk, and Src SH2 domains due to a single residue variation.

PubMed

Ayrapetov, Marina K; Nam, Nguyen Hai; Ye, Guofeng; Kumar, Anil; Parang, Keykavous; Sun, Gongqin

2005-07-08

The C-terminal Src kinase (Csk) family of protein tyrosine kinases contains two members: Csk and Csk homologous kinase (Chk). Both phosphorylate and inactivate Src family kinases. Recent reports suggest that the Src homology (SH) 2 domains of Csk and Chk may bind to different phosphoproteins, which provides a basis for different cellular functions for Csk and Chk. To verify and characterize such a functional divergence, we compared the binding properties of the Csk, Chk, and Src SH2 domains and investigated the structural basis for the functional divergence. First, the study demonstrated striking functional differences between the Csk and Chk SH2 domains and revealed functional similarities between the Chk and Src SH2 domains. Second, structural analysis and mutagenic studies revealed that the functional differences among the three SH2 domains were largely controlled by one residue, Glu127 in Csk, Ile167 in Chk, and Lys200 in Src. Mutating these residues in the Csk or Chk SH2 domain to the Src counterpart resulted in dramatic gain of function similar to Src SH2 domain, whereas mutating Lys200 in Src SH2 domain to Glu (the Csk counterpart) resulted in loss of Src SH2 function. Third, a single point mutation of E127K rendered Csk responsive to activation by a Src SH2 domain ligand. Finally, the optimal phosphopeptide sequence for the Chk SH2 domain was determined. These results provide a compelling explanation for the functional differences between two homologous protein tyrosine kinases and reveal a new structure-function relationship for the SH2 domains.

Chk2 mediates RITA-induced apoptosis.

PubMed

de Lange, J; Verlaan-de Vries, M; Teunisse, A F A S; Jochemsen, A G

2012-06-01

Reactivation of the p53 tumor-suppressor protein by small molecules like Nutlin-3 and RITA (reactivation of p53 and induction of tumor cell apoptosis) is a promising strategy for cancer therapy. The molecular mechanisms involved in the responses to RITA remain enigmatic. Several groups reported the induction of a p53-dependent DNA damage response. Furthermore, the existence of a p53-dependent S-phase checkpoint has been suggested, involving the checkpoint kinase Chk1. We have recently shown synergistic induction of apoptosis by RITA in combination with Nutlin-3, and we observed concomitant Chk2 phosphorylation. Therefore, we investigated whether Chk2 contributes to the cellular responses to RITA. Strikingly, the induction of apoptosis seemed entirely Chk2 dependent. Transcriptional activity of p53 in response to RITA required the presence of Chk2. A partial rescue of apoptosis observed in Noxa knockdown cells emphasized the relevance of p53 transcriptional activity for RITA-induced apoptosis. In addition, we observed an early p53- and Chk2-dependent block of DNA replication upon RITA treatment. Replicating cells seemed more prone to entering RITA-induced apoptosis. Furthermore, the RITA-induced DNA damage response, which was not a secondary effect of apoptosis induction, was strongly attenuated in cells lacking p53 or Chk2. In conclusion, we identified Chk2 as an essential mediator of the cellular responses to RITA.

Chk2 mediates RITA-induced apoptosis

PubMed Central

de Lange, J; Verlaan-de Vries, M; Teunisse, A F A S; Jochemsen, A G

2012-01-01

Reactivation of the p53 tumor-suppressor protein by small molecules like Nutlin-3 and RITA (reactivation of p53 and induction of tumor cell apoptosis) is a promising strategy for cancer therapy. The molecular mechanisms involved in the responses to RITA remain enigmatic. Several groups reported the induction of a p53-dependent DNA damage response. Furthermore, the existence of a p53-dependent S-phase checkpoint has been suggested, involving the checkpoint kinase Chk1. We have recently shown synergistic induction of apoptosis by RITA in combination with Nutlin-3, and we observed concomitant Chk2 phosphorylation. Therefore, we investigated whether Chk2 contributes to the cellular responses to RITA. Strikingly, the induction of apoptosis seemed entirely Chk2 dependent. Transcriptional activity of p53 in response to RITA required the presence of Chk2. A partial rescue of apoptosis observed in Noxa knockdown cells emphasized the relevance of p53 transcriptional activity for RITA-induced apoptosis. In addition, we observed an early p53- and Chk2-dependent block of DNA replication upon RITA treatment. Replicating cells seemed more prone to entering RITA-induced apoptosis. Furthermore, the RITA-induced DNA damage response, which was not a secondary effect of apoptosis induction, was strongly attenuated in cells lacking p53 or Chk2. In conclusion, we identified Chk2 as an essential mediator of the cellular responses to RITA. PMID:22158418

Chk1 phosphorylation at Ser286 and Ser301 occurs with both stalled DNA replication and damage checkpoint stimulation.

PubMed

Ikegami, Yosuke; Goto, Hidemasa; Kiyono, Tohru; Enomoto, Masato; Kasahara, Kousuke; Tomono, Yasuko; Tozawa, Keiichi; Morita, Akimichi; Kohri, Kenjiro; Inagaki, Masaki

2008-12-26

We previously reported Chk1 to be phosphorylated at Ser286 and Ser301 by cyclin-dependent kinase (Cdk) 1 during mitosis [T. Shiromizu et al., Genes Cells 11 (2006) 477-485]. Here, we demonstrated that Chk1-Ser286 and -Ser301 phosphorylation also occurs in hydroxyurea (HU)-treated or ultraviolet (UV)-irradiated cells. Unlike the mitosis case, however, Chk1 was phosphorylated not only at Ser286 and Ser301 but also at Ser317 and Ser345 in the checkpoint response. Treatment with Cdk inhibitors diminished Chk1 phosphorylation at Ser286 and Ser301 but not at Ser317 and Ser345 with the latter. In vitro analyses revealed Ser286 and Ser301 on Chk1 to serve as two major phosphorylation sites for Cdk2. Immunoprecipitation analyses further demonstrated that Ser286/Ser301 and Ser317/Ser345 phosphorylation occur in the same Chk1 molecule during the checkpoint response. In addition, Ser286/Ser301 phosphorylation by Cdk2 was observed in Chk1 mutated to Ala at Ser317 and Ser345 (S317A/S345A), as well as Ser317/Ser345 phosphorylation by ATR was in S286A/S301A. Therefore, Chk1 phosphorylation in the checkpoint response is regulated not only by ATR but also by Cdk2.

RSV associated hospitalizations in children in Karachi, Pakistan: Implications for vaccine prevention strategies.

PubMed

Ali, Asad; Yousafzai, Mohammad Tahir; Waris, Rabbia; Jafri, Fatima; Aziz, Fatima; Abbasi, Imran Naeem; Zaidi, Anita

2017-07-01

Major progress is being made in vaccines against Respiratory Syncytial Virus (RSV), with multiple vaccine candidates currently in the clinical phase of development. Making an investment case for public sector financing of RSV vaccine will require estimation of burden, cost-effectiveness, and impact. The aim of this study is to determine the proportion, age distribution and clinical spectrum of RSV associated hospitalizations in children in Karachi, Pakistan. A three years prospective study was conducted at the Aga Khan University Hospital in Karachi, a city of 20 million in south Pakistan, from August 2009 to June 2012. Children less than five years old admitted with acute respiratory infections (ARI) were enrolled. Throat swabs were collected and tested for RSV using real-time PCR. Multivariable log binomial regression analysis was performed to identify the associated factors of RSV infection. Out of 1150 children enrolled, RSV was detected among 223 (19%). Highest rate of RSV detection was in young infants less than 3 months of age (48/168, 29%), which accounted for 22% of all RSV detected. Most common diagnosis in RSV positive infants (<12 months of age) was bronchiolitis followed by pneumonia, while in older children between the ages of one and 5 years of age, pneumonia and asthma were the most common diagnosis. Although identified year-round, RSV was most prevalent from August to October with peak in September, coinciding with the rainy season. This study identified RSV to be independently associated with younger age (P = 0.036), rainy season (P < 0.001), post-tussive emesis (P = 0.008), intubation (P = 0.003), and discharge diagnosis of bronchiolitis (P = 0.004). Vaccines against RSV that target this age group are likely to yield remarkable benefit. © 2017 Wiley Periodicals, Inc.

Clinical and demographic features of burn injuries in karachi: a six-year experience at the burns centre, civil hospital, Karachi

PubMed Central

Ali, S.A.; Hamiz-ul-Fawwad, S.; Al-Ibran, E.; Ahmed, G.; Saleem, A.; Mustafa, D.; Hussain, M.

2016-01-01

Summary Burn injuries are a leading cause of morbidity and mortality, with 195,000 deaths annually. This study was conducted to identify the demographics of burn victims and the effect of different variables on the outcome of their injuries. 4016 patients admitted to the Burns Centre, Civil Hospital Karachi from January 2006 to December 2011 were retrospectively analyzed. Demographics, burn injury details and their outcome were recorded in a pre-designed questionnaire. Injuries were categorized as: fire, chemical, scald or electrical. To estimate total body surface area (TBSA) burned in adults, the rule of nines was used. For children and infants, the Lund-Browder chart was employed. SPSS v16.0 software was used for analysis. Frequencies and percentages of all variables, and the measure of central tendencies and dispersion for continuous variables were calculated. Cross tabs were used to assess mortality. Mean age was 28.13 years. More than half of the cases (n=2337, 58.2%) were aged between 16-30 years. Labourers, housewives and students were the most commonly affected groups. Burn injuries by flame/fire and electricity were most common. Most cases were accidental, followed by suicide attempts and homicides. Mean percentage of TBSA affected was 35.49%. Mean duration of hospital stay was 16.45 days. 50.6% of the expired cases were females. The mean age of expired patients was 30.07 while for patients who survived it was 27.01 years. The outcome of burn injuries is related to various demographic factors. Female gender, increasing age, burn injuries following suicide attempts and greater surface area involvement predict poor outcome. PMID:27857643

Identification of a Bis-guanylhydrazone [4,4'-Diacetyldiphenylurea-bis(guanylhydrazone); NSC 109555] as a novel chemotype for inhibition of Chk2 kinase.

PubMed

Jobson, Andrew G; Cardellina, John H; Scudiero, Dominic; Kondapaka, Sudhir; Zhang, Hongliang; Kim, Hijoo; Shoemaker, Robert; Pommier, Yves

2007-10-01

Chk2 is a protein kinase involved in the ATM-dependent checkpoint pathway (http://discover.nci.nih.gov/mim). This pathway is activated by genomic instability and DNA damage and results in either cell cycle arrest, to allow DNA repair to occur, or cell death (apoptosis). Chk2 is activated by ATM-mediated phosphorylation and autophosphorylation and in turn phosphorylates its downstream targets (Cdc25A, Cdc25C, BRCA1, p53, Hdmx, E2F1, PP2A, and PML). Inhibition of Chk2 has been proposed to sensitize p53-deficient cells as well as protect normal tissue after exposure to DNA-damaging agents. We have developed a drug-screening program for specific Chk2 inhibitors using a fluorescence polarization assay, immobilized metal ion affinity-based fluorescence polarization (IMAP). This assay detects the degree of phosphorylation of a fluorescently linked substrate by Chk2. From a screen of over 100,000 compounds from the NCI Developmental Therapeutics Program, we identified a bis-guanylhydrazone [4,4'-diacetyldiphenylureabis(guanylhydrazone); NSC 109555] as a lead compound. In vitro data show the specific inhibition of Chk2 kinase activity by NSC 109555 using in vitro kinase assays and kinase-profiling experiments. NSC 109555 was shown to be a competitive inhibitor of Chk2 with respect to ATP, which was supported by docking of NSC 109555 into the ATP binding pocket of the Chk2 catalytic domain. The potency of NSC 109555 was comparable with that of other known Chk2 inhibitors, such as debromohymenialdisine and 2-arylbenzimidazole. These data define a novel chemotype for the development of potent and selective inhibitors of Chk2. This class of drugs may ultimately be useful in combination with current DNA-damaging agents used in the clinic.

Dissecting cellular responses to irradiation via targeted disruptions of the ATM-CHK1-PP2A circuit

PubMed Central

Palii, Stela S.; Cui, Yuxia; Innes, Cynthia L.; Paules, Richard S.

2013-01-01

Exposure of proliferating cells to genotoxic stresses activates a cascade of signaling events termed the DNA damage response (DDR). The DDR preserves genetic stability by detecting DNA lesions, activating cell cycle checkpoints and promoting DNA damage repair. The phosphoinositide 3-kinase-related kinases (PIKKs) ataxia telangiectasia-mutated (ATM), ATM and Rad 3-related kinase (ATR) and DNA-dependent protein kinase (DNA-PK) are crucial for sensing lesions and signal transduction. The checkpoint kinase 1 (CHK1) is a traditional ATR target involved in DDR and normal cell cycle progression and represents a pharmacological target for anticancer regimens. This study employed cell lines stably depleted for CHK1, ATM or both for dissecting cross-talk and compensatory effects on G₂/M checkpoint in response to ionizing radiation (IR). We show that a 90% depletion of CHK1 renders cells radiosensitive without abrogating their IR-mediated G₂/M checkpoint arrest. ATM phosphorylation is enhanced in CHK1-deficient cells compared with their wild-type counterparts. This correlates with lower nuclear abundance of the PP2A catalytic subunit in CHK1-depleted cells. Stable depletion of CHK1 in an ATM-deficient background showed only a 50% reduction from wild-type CHK1 protein expression levels and resulted in an additive attenuation of the G₂/M checkpoint response compared with the individual knockdowns. ATM inhibition and 90% CHK1 depletion abrogated the early G₂/M checkpoint and precluded the cells from mounting an efficient compensatory response to IR at later time points. Our data indicates that dual targeting of ATM and CHK1 functionalities disrupts the compensatory response to DNA damage and could be exploited for developing efficient anti-neoplastic treatments. PMID:23462183

The radioresistance to killing of A1-5 cells derives from activation of the Chk1 pathway

NASA Technical Reports Server (NTRS)

Hu, B.; Zhou, X. Y.; Wang, X.; Zeng, Z. C.; Iliakis, G.; Wang, Y.

2001-01-01

Checkpoints respond to DNA damage by arresting the cell cycle to provide time for facilitating repair. In mammalian cells, the G(2) checkpoint prevents the Cdc25C phosphatase from removing inhibitory phosphate groups from the mitosis-promoting kinase Cdc2. Both Chk1 and Chk2, the checkpoint kinases, can phosphorylate Cdc25C and inactivate its in vitro phosphatase activity. Therefore, both Chk1 and Chk2 are thought to regulate the activation of the G(2) checkpoint. Here we report that A1-5, a transformed rat embryo fibroblast cell line, shows much more radioresistance associated with a much stronger G(2) arrest response when compared with its counterpart, B4, although A1-5 and B4 cells have a similar capacity for nonhomologous end-joining DNA repair. These phenotypes of A1-5 cells are accompanied by a higher Chk1 expression and a higher phosphorylation of Cdc2. On the other hand, Chk2 expression increases slightly following radiation; however, it has no difference between A1-5 and B4 cells. Caffeine or UCN-01 abolishes the extreme radioresistance with the strong G(2) arrest and at the same time reduces the phosphorylation of Cdc2 in A1-5 cells. In addition, Chk1 but not Chk2 antisense oligonucleotide sensitizes A1-5 cells to radiation-induced killing and reduces the G(2) arrest of the cells. Taken together these results suggest that the Chk1/Cdc25C/Cdc2 pathway is the major player for the radioresistance with G(2) arrest in A1-5 cells.

Loss of CHK1 function impedes DNA damage-induced FANCD2 monoubiquitination but normalizes the abnormal G2 arrest in Fanconi anemia.

PubMed

Guervilly, Jean-Hugues; Macé-Aimé, Gaëtane; Rosselli, Filippo

2008-03-01

Fanconi anemia (FA) is a cancer-prone hereditary disease resulting from mutations in one of the 13 genes defining the FANC/BRCA pathway. This pathway is involved in the cellular resistance to DNA-cross-linking agents. How the FANC/BRCA pathway is activated and why its deficiency leads to the accumulation of FA cells with a 4N DNA content are still poorly answered questions. We investigated the involvement of ATR pathway members in these processes. We show here that RAD9 and RAD17 are required for DNA interstrand cross-link (ICL) resistance and for the optimal activation of FANCD2. Moreover, we demonstrate that CHK1 and its interacting partner CLASPIN that act downstream in the ATR pathway are required for both FANCD2 monoubiquitination and assembling in subnuclear foci in response to DNA damage. Paradoxically, in the absence of any genotoxic stress, CHK1 or CLASPIN depletion results in an increased basal level of FANCD2 monoubiquitination and focalization. We also demonstrate that the ICL-induced accumulation of FA cells in late S/G2 phase is dependent on ATR and CHK1. In agreement with this, CHK1 phosphorylation is enhanced in FA cells, and chemical inhibition of the ATR/CHK1 axis in FA lymphoblasts decreases their sensitivity to mitomycin C. In conclusion, this work describes a complex crosstalk between CHK1 and the FANC/BRCA pathway: CHK1 activates this pathway through FANCD2 monoubiquitination, whereas FA deficiency leads to a CHK1-dependent G2 accumulation, raising the possibility that the FANC/BRCA pathway downregulates CHK1 activation.

A protein phosphatase feedback mechanism regulates the basal phosphorylation of Chk2 kinase in the absence of DNA damage.

PubMed

Carlessi, Luigi; Buscemi, Giacomo; Fontanella, Enrico; Delia, Domenico

2010-10-01

The checkpoint kinase Chk2 is an effector component of the ATM-dependent DNA damage response (DDR) pathway. The activation of Chk2 by genotoxic stress involves its phosphorylation on T68 by ATM and additional auto/transphosphorylations. Here we demonstrate that in unperturbed cells, chemical inhibition of Chk2 by VRX0466617 (VRX) enhances the phosphorylation of Chk2-T68 throughout the cell cycle phases. This event, dependent on the presence of ATM and catalytically functional Chk2, is not consequential to DNA damage, as neither gamma-H2AX nuclear foci nor increased ATM activation is detected in VRX-treated cells, suggesting the involvement of other regulatory proteins. As serine/threonine protein phosphatases (PPs) regulate the phosphorylation and deactivation of proteins of the DDR pathway, we analyzed their role in phospho-T68-Chk2 regulation. We found that intracellular inhibition of PP1 and PP2A-like activities by okadaic acid markedly raised the accumulation of Chk2-pT68 without DNA damage induction, and this phenomenon was also seen when PP1-C, PP2A-C, and Wip1/PPM1D were simultaneously knockdown by siRNA. Altogether, these data indicate a novel mechanism in undamaged cells where PPs function to maintain the balance between ATM and its direct substrate Chk2 through a regulatory circuit. Copyright © 2010 Elsevier B.V. All rights reserved.

Analysis of association between type of amblyopia and gender at a tertiary care hospital in Karachi.

PubMed

Siddiqui, Abdul Hameed; Raza, Syed Akhtar; Ghazipura, Arifa; Hussain, Muhammad Azhar; Iqbal, Sarwat; Ahsan, Kamran; Nadeem, Adnan

2016-05-01

To analyse the frequency of different types of amblyopia and its association with gender. The cross-sectional study was conducted from March 2014 to October 2014 at the Department of Ophthalmology of a tertiary care hospital inKarachi. The patients were classified into different types of amblyopia like anisometropic, strabismic, sensory deprivation and meridional amblyopia. Stratification was done according to age, gender and type of amblyopia by using SPSS version 21. Out of 130 patients, 71 were male and 59 were female. The amblyopia rate determined was anisometropic 69.23%, strabismic amblyopia 21.51% and others 9.23%. The mean age of subjects was 18.02±9 years. Type of amblyopia was independent of gender, and anisometropic amblyopia was the most common type of amblyopia found in both genders. This study found no significant association between gender and types of amblyopia and anisometropic amblyopia was the most common type of amblyopia in the data collected.

Radiation activated CHK1/MEPE pathway may contribute to microgravity-induced bone density loss

NASA Astrophysics Data System (ADS)

Zhang, Xiangming; Wang, Ping; Wang, Ya

2015-11-01

Bone density loss in astronauts on long-term space missions is a chief medical concern. Microgravity in space is the major cause of bone density loss (osteopenia), and it is believed that high linear energy transfer (LET) radiation in space exacerbates microgravity-induced bone density loss; however, the mechanism remains unclear. It is known that acidic serine- and aspartate-rich motif (ASARM) as a small peptide released by matrix extracellular phosphoglycoprotein (MEPE) promotes osteopenia. We previously discovered that MEPE interacted with checkpoint kinase 1 (CHK1) to protect CHK1 from ionizing radiation promoted degradation. In this study, we addressed whether the CHK1-MEPE pathway activated by radiation contributes to the effects of microgravity on bone density loss. We examined the CHK1, MEPE and secreted MEPE/ASARM levels in irradiated (1 Gy of X-ray) and rotated cultured human osteoblast cells. The results showed that radiation activated CHK1, decreased the levels of CHK1 and MEPE in human osteoblast cells and increased the release of MEPE/ASARM. These results suggest that the radiation-activated CHK1/MEPE pathway exacerbates the effects of microgravity on bone density loss, which may provide a novel targeting factor/pathway for a future countermeasure design that could contribute to reducing osteopenia in astronauts.

Chk1 protects against chromatin bridges by constitutively phosphorylating BLM serine 502 to inhibit BLM degradation.

PubMed

Petsalaki, Eleni; Dandoulaki, Maria; Morrice, Nick; Zachos, George

2014-09-15

Chromatin bridges represent incompletely segregated chromosomal DNA connecting the anaphase poles and can result in chromosome breakage. The Bloom's syndrome protein helicase (BLM, also known as BLMH) suppresses formation of chromatin bridges. Here, we show that cells deficient in checkpoint kinase 1 (Chk1, also known as CHEK1) exhibit higher frequency of chromatin bridges and reduced BLM protein levels compared to controls. Chk1 inhibition leads to BLM ubiquitylation and proteasomal degradation during interphase. Furthermore, Chk1 constitutively phosphorylates human BLM at serine 502 (S502) and phosphorylated BLM localises to chromatin bridges. Mutation of S502 to a non-phosphorylatable alanine residue (BLM-S502A) reduces the stability of BLM, whereas expression of a phospho-mimicking BLM-S502D, in which S502 is mutated to aspartic acid, stabilises BLM and prevents chromatin bridges in Chk1-deficient cells. In addition, wild-type but not BLM-S502D associates with cullin 3, and cullin 3 depletion rescues BLM accumulation and localisation to chromatin bridges after Chk1 inhibition. We propose that Chk1 phosphorylates BLM-S502 to inhibit cullin-3-mediated BLM degradation during interphase. These results suggest that Chk1 prevents deleterious anaphase bridges by stabilising BLM. © 2014. Published by The Company of Biologists Ltd.

How well can physicians manage tuberculosis? A public-private sector comparison from Karachi, Pakistan.

PubMed

Naseer, Maliha; Khawaja, Ali; Pethani, Amin S; Aleem, Salik

2013-10-25

Tuberculosis (TB) is endemic in Pakistan which ranks fifth amongst the twenty two countries designated to be highly burdened by TB according to the World Health Organization. However, there is paucity of data regarding the knowledge of diagnosis of TB and its management amongst public and private practitioners. In this study, we endeavor to identify this gap in knowledge regarding the diagnosis and management of TB between public and private doctors and the factors affecting these knowledge scores in urban Pakistan. This cross sectional survey was conducted between June and December 2011. Doctors from public hospitals, private hospitals and private clinics scattered in all eighteen towns of Karachi were included in the study. Qualified MBBS doctors working in any specialty were eligible to participate whereas doctors working in both the public and private sectors were excluded from the study. Vignette based clinical scenarios were given to assess the knowledge score regarding the diagnosis and management of TB. A total of 196 doctors participated in the study. There was a significant difference between private and public physicians in terms of age and years of practice (p-value <0.05). Significant differences in the proportion of knowledge scores were observed between the public and private doctors and National TB Control Program trained and untrained doctors in Karachi. Factors associated with inadequate knowledge scores were being female gender [OR: 2.76 (95% CI: 1.418-5.384)], private employment status [OR: 1.50 (95% CI: 1.258-2.439)], and not trained by NTP [OR: 2.98 (95% CI: 1.286-3.225)] on multivariate logistic regression analysis. It is concluded that a knowledge gap exists between the public and private doctors in Karachi. Strengthening of currently implemented public private mix model along with improvement in the trainings of public and private practitioners is highly recommended to control TB in Pakistan.

Reducing length of stay in hospital for very low birthweight infants by involving mothers in a stepdown unit: an experience from Karachi (Pakistan).

PubMed

Bhutta, Zulfiqar A; Khan, Iqtidar; Salat, Suhail; Raza, Farukh; Ara, Husan

2004-11-13

Clinical care of infants with a very low birth weight (less than 1500 g) in developing countries can be labour intensive and is often associated with a prolonged stay in hospital. The Aga Khan University Medical Center in Karachi, Pakistan, established a neonatal intensive care unit in 1987. By 1993-4, very low birthweight infants remained in hospital for 18-21 days. A stepdown unit was established in September 1994, with mothers providing all basic nursing care for their infants before being discharged under supervision. We analysed neonatal outcomes for the time periods before and after the stepdown unit was created (1987-94 and 1995-2001). We compared these two time periods for survival after birth until discharge, morbidity patterns during hospitalisation, length of stay in hospital, and readmission rates to hospital in the four weeks after discharge. Of 509 consecutive, very low birthweight infants, 494 (97%) preterm and 140 (28%) weighing < 1000 g at birth), 391 (76%) survived to discharge from the hospital. The length of hospitalisation fell significantly from 1987-90, when it was 34 (SD 18) days, to 16 (SD 14) days in 1999-2001 (P < 0.001). Readmission rates to hospital did not rise, nor did adverse outcomes at 12 months of age. Our results indicate that it is possible to involve mothers in the active care of their very low birthweight infants before discharge. This may translate into earlier discharge from hospital to home settings without any increase in short term complications and readmissions.

Prevalence of vitamin D deficiency and insufficiency among adult asthmatic patients in Karachi.

PubMed

Kamran, Afshan; Alam, Syed Mahboob; Qadir, Farida

2014-11-01

Vitamin D deficiency has assumed pandemic proportions all over the world. It has been documented as a frequent problem in studies of young adults, elderly person and children in other countries, but there is no reliable data on vitamin D status of adult asthmatic patients in Pakistan. To determine the prevalence of vitamin D deficiency and insufficiency in adult asthmatic patients with moderate to severe asthma using a cross-sectional study design in Basic Medical Sciences Institute, Jinnah Postgraduate Medical Centre, Karachi.311 adult asthmatic patients with moderate to severe asthma were recruited from JPMC, tertiary care hospital in Karachi. Questionnaires were administered together demographics, height, weight, nutritional and physical activity assessment. Blood samples for vitamin D measurement were also taken. Results show high prevalence of vitamin D deficiency and insufficiency (88.10%) in adult patients with moderate to severe persistent asthma. Vitamin D deficiency and insufficiency was more frequently observed in female than in male patients.67.66% of the female patients had serum vitamin D level less than 20 ng/ml as compare to 56.1% of the male patients (p=0.01).

Current trends in treatment of obesity in Karachi and possibilities of cost minimization.

PubMed

Hussain, Mirza Izhar; Naqvi, Baqir Shyum

2015-03-01

Our study finds out drug usage trends in over weight and obese patients without any compelling indications in Karachi, looks for deviations of current practices from evidence based antihypertensive therapeutic guidelines and identifies not only cost minimization opportunities but also communication strategies to improve patients' awareness and compliance to achieve therapeutic goal. In present study two sets were used. Randomized stratified independent surveys were conducted in hospital doctors and family physicians (general practitioners), using pretested questionnaires. Sample size was 100. Statistical analysis was conducted on Statistical Package for Social Science (SPSS). Opportunities of cost minimization were also analyzed. One the basis of doctors' feedback, preference is given to non-pharmacologic management of obesity. Mass media campaign and media usage were recommended to increase patients awareness and patients' education along with strengthening family support systems was recommended for better compliance of the patients to doctor's advice. Local therapeutic guidelines for weight reduction were not found. Feedbacks showed that global therapeutic guidelines were followed by the doctors practicing in the community and hospitals in Karachi. However, high price branded drugs were used instead of low priced generic therapeutic equivalents. Patient's education is required for better awareness and improving patients' compliance. The doctors found preferring brand leaders instead of low cost options. This trend increases cost of therapy by 0.59 to 4.17 times. Therefore, there are great opportunities for cost minimization by using evidence-based clinically effective and safe medicines.

Fetomaternal outcome of pregnancy with Mitral stenosis

PubMed Central

Ahmed, Nazia; Kausar, Hafeeza; Ali, Lubna; Rakhshinda

2015-01-01

Objective: To evaluate the frequency of fetomaternal outcome of pregnancy with Mitral stenosis admitted in Civil Hospital Karachi. Methods: It was a two years descriptive study done in the Department of Obstetrics and Gynaecology Civil Hospital Karachi. All pregnant women with a known or newly diagnosed Mitral stenosis on echocardiography were included in the study. History was taken regarding age, parity, gestational age (calculated by ultrasound) and complaints. Mode of delivery and Maternal mortality noted. Foetal outcome was analyzed by birth weight and Apgar score. Results: A total of 101 patients meeting the inclusion criteria were enrolled in the study. The ages of the women ranged between 20-29 years (69%) and 81% were multigravidas. Vaginal delivery occurred in 67 (66.3%) women and 78.3% were term pregnancies. Preterm deliveries were 21.8% and 27.7% newborns were low birth weight. APGAR score <7 was found in 14.9% of neonates and 9 babies had intrauterine death. Low ejection fraction<55% was diagnosed in 20(13.9%) women and Maternal mortality was found in two cases. Conclusion: Heart disease in pregnancy is associated with significant morbidity, it should be carefully managed in a tertiary care hospital to obtain optimum maternal and foetal outcome. PMID:26150860

Association of tobacco use and other determinants with pregnancy outcomes: a multicentre hospital-based case-control study in Karachi, Pakistan.

PubMed

Rozi, Shafquat; Butt, Zahid Ahmad; Zahid, Nida; Wasim, Saba; Shafique, Kashif

2016-09-20

The study aimed to identify the effects of maternal tobacco consumption during pregnancy and other factors on birth outcomes and obstetric complications in Karachi, Pakistan. A multicentre hospital-based case-control study. Four leading maternity hospitals of Karachi. A random sample of 1275 women coming to the gynaecology and obstetric department of selected hospitals for delivery was interviewed within 48 hours of delivery from wards. Cases were women with adverse birth outcomes and obstetric complications, while controls were women who had normal uncomplicated delivery. Adverse birth outcomes (preterm delivery, low birth weight, stillbirth, low Apgar score) and obstetric complications (antepartum haemorrhage, caesarean section, etc). Final multiple logistic regression analysis revealed that with every 1 year increase in age the odds of being a case was 1.03 times as compared with being a control. Tobacco use (adjusted OR (aOR): 2.24; 95% CI 1.56 to 3.23), having no slits in the kitchen (proxy indicator for indoor air pollution) (aOR=1.90; 95% CI 1.05 to 3.43), gravidity (aOR=0.83; 95% CI 0.73 to 0.93), non-booked hospital cases (aOR=1.87; 95% CI 1.38 to 2.74), history of stillbirth (aOR=4.06; 95% CI 2.36 to 6.97), miscarriages (aOR=1.91; 95% CI 1.27 to 2.85) and preterm delivery (aOR=6.04; 95% CI 2.52 to 14.48) were significantly associated with being a case as compared with control. This study suggests that women who had adverse pregnancy outcomes were more likely to have exposure to tobacco, previous history of adverse birth outcomes and were non-booked cases. Engagement of stakeholders in tobacco control for providing health education, incorporating tobacco use in women in the tobacco control policy and designing interventions for tobacco use cessation is warranted. Prenatal care and health education might help in preventing such adverse events. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

ATR inhibition broadly sensitizes ovarian cancer cells to chemotherapy independent of BRCA status

PubMed Central

Huntoon, Catherine J.; Flatten, Karen S.; Wahner Hendrickson, Andrea E.; Huehls, Amelia M.; Sutor, Shari L.; Kaufmann, Scott H.; Karnitz, Larry M.

2013-01-01

Replication stress and DNA damage activate the ATR-CHK1 checkpoint signaling pathway that licenses repair and cell survival processes. In this study, we examined the respective roles of the ATR and CHK1 kinases in ovarian cancer cells using genetic and pharmacological inhibitors of in combination with cisplatin, topotecan, gemcitabine and the poly(ADP-ribose)-polymerase (PARP) inhibitor veliparib (ABT-888), four agents with clinical activity in ovarian cancer. RNAi-mediated depletion or inhibition of ATR sensitized ovarian cancer cells to all four agents. In contrast, while cisplatin, topotecan and gemcitabine each activated CHK1, RNAi-mediated depletion or inhibition of this kinase in cells sensitized them only to gemcitabine. Unexpectedly, we found that neither the ATR kinase inhibitor VE-821 or the CHK1 inhibitor MK-8776 blocked ATR-mediated CHK1 phosphorylation or autophosphorylation, two commonly used readouts for inhibition of the ATR-CHK1 pathway. Instead, their ability to sensitize cells correlated with enhanced CDC25A levels. Additionally, we also found that VE-821 could further sensitize BRCA1-depleted cells to cisplatin, topotecan and veliparib beyond the potent sensitization already caused by their deficiency in homologous recombination. Taken together, our results established that ATR and CHK1 inhibitors differentially sensitize ovarian cancer cells to commonly used chemotherapy agents, and that CHK1 phosphorylation status may not offer a reliable marker for inhibition of the ATR-CHK1 pathway. A key implication of our work is the clinical rationale it provides to evaluate ATR inhibitors in combination with PARP inhibitors in BRCA1/2-deficient cells. PMID:23548269

Interferon-gamma enhances radiation-induced cell death via downregulation of Chk1

PubMed Central

Kim, Kwang Seok; Choi, Kyu Jin; Bae, Sangwoo

2012-01-01

Interferon-gamma (IFNγ) is a cytokine with roles in immune responses as well as in tumor control. Interferon is often used in cancer treatment together with other therapies. Here we report a novel approach to enhancement of cancer cell killing by combined treatment of IFNγ with ionizing radiation. We found that IFNγ treatment alone in HeLa cells induced phosphorylation of Chk1 in a time- and dose-dependent manner, and resulted in cell arrest. Moreover IFNγ treatment was correlated with attenuation of Chk1 as the treatment shortened protein half-life of Chk1. As Chk1 is an essential cell cycle regulator for viability after DNA damage, attenuation of Chk1 by IFNγ pre-treatment in HeLa cells resulted in increased cell death following ionizing radiation about 2-folds than ionizing radiation treatment alone whereas IFNγ treatment alone had little effect on cell death. X-linked inhibitor of apoptosis-associated factor 1 (XAF1), an IFN-induced gene, seems to partly regulate IFNγ-induced Chk1 destabilization and radiation sensitivity because transient depletion of XAF1 by siRNA prevented IFNγ-induced Chk1 attenuation and partly protected cells from IFNγ-enhanced radiation cell killing. Therefore the results provide a novel rationale to combine IFNγ pretreatment and DNA-damaging anti-cancer drugs such as ionizing radiation to enhance cancer cell killing. PMID:22825336

Enhancement of hypoxia-activated prodrug TH-302 anti-tumor activity by Chk1 inhibition.

PubMed

Meng, Fanying; Bhupathi, Deepthi; Sun, Jessica D; Liu, Qian; Ahluwalia, Dharmendra; Wang, Yan; Matteucci, Mark D; Hart, Charles P

2015-05-21

The hypoxia-activated prodrug TH-302 is reduced at its nitroimidazole group and selectively under hypoxic conditions releases the DNA cross-linker bromo-isophosphoramide mustard (Br-IPM). Here, we have explored the effect of Chk1 inhibition on TH-302-mediated pharmacological activities. We employed in vitro cell viability, DNA damage, cellular signaling assays and the in vivo HT29 human tumor xenograft model to study the effect of Chk1inhibition on TH-302 antitumor activities. TH-302 cytotoxicity is greatly enhanced by Chk1 inhibition in p53-deficient but not in p53-proficient human cancer cell lines. Chk1 inhibitors reduced TH-302-induced cell cycle arrest via blocking TH-302-induced decrease of phosphorylation of histone H3 and increasing Cdc2-Y15 phosphorylation. Employing the single-cell gel electrophoresis (comet) assay, we observed a potentiation of the TH-302 dependent tail moment. TH-302 induced γH2AX and apoptosis were also increased upon the addition of Chk1 inhibitor. Potentiation of TH-302 cytotoxicity by Chk1 inhibitor was only observed in cell lines proficient in, but not deficient in homology-directed DNA repair. We also show that combination treatment led to lowering of Rad51 expression levels as compared to either agent alone. In vivo data demonstrate that Chk1 inhibitor enhances TH-302 anti-tumor activity in p53 mutant HT-29 human tumor xenografts, supporting the hypothesis that these in vitro results can translate to enhanced in vivo efficacy of the combination. TH-302-mediated in vitro and in vivo anti-tumor activities were greatly enhanced by the addition of Chk1 inhibitors. The preclinical data presented in this study support a new approach for the treatment of p53-deficient hypoxic cancers by combining Chk1 inhibitors with the hypoxia-activated prodrug TH-302.

Inhibition of autophagy enhances DNA damage-induced apoptosis by disrupting CHK1-dependent S phase arrest

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liou, Jong-Shian; Wu, Yi-Chen; Yen, Wen-Yen

2014-08-01

DNA damage has been shown to induce autophagy, but the role of autophagy in the DNA damage response and cell fate is not fully understood. BO-1012, a bifunctional alkylating derivative of 3a-aza-cyclopenta[a]indene, is a potent DNA interstrand cross-linking agent with anticancer activity. In this study, BO-1012 was found to reduce DNA synthesis, inhibit S phase progression, and induce phosphorylation of histone H2AX on serine 139 (γH2AX) exclusively in S phase cells. Both CHK1 and CHK2 were phosphorylated in response to BO-1012 treatment, but only depletion of CHK1, but not CHK2, impaired BO-1012-induced S phase arrest and facilitated the entry ofmore » γH2AX-positive cells into G2 phase. CHK1 depletion also significantly enhanced BO-1012-induced cell death and apoptosis. These results indicate that BO-1012-induced S phase arrest is a CHK1-dependent pro-survival response. BO-1012 also resulted in marked induction of acidic vesicular organelle (AVO) formation and microtubule-associated protein 1 light chain 3 (LC3) processing and redistribution, features characteristic of autophagy. Depletion of ATG7 or co-treatment of cells with BO-1012 and either 3-methyladenine or bafilomycin A1, two inhibitors of autophagy, not only reduced CHK1 phosphorylation and disrupted S phase arrest, but also increased cleavage of caspase-9 and PARP, and cell death. These results suggest that cells initiate S phase arrest and autophagy as pro-survival responses to BO-1012-induced DNA damage, and that suppression of autophagy enhances BO-1012-induced apoptosis via disruption of CHK1-dependent S phase arrest. - Highlights: • Autophagy inhibitors enhanced the cytotoxicity of a DNA alkylating agent, BO-1012. • BO-1012-induced S phase arrest was a CHK1-dependent pro-survival response. • Autophagy inhibition enhanced BO-1012 cytotoxicity via disrupting the S phase arrest.« less

Chk1 and Mps1 jointly regulate correction of merotelic kinetochore attachments.

PubMed

Petsalaki, Eleni; Zachos, George

2013-03-01

If uncorrected, merotelic kinetochore attachments can induce mis-segregated chromosomes in anaphase. We show that checkpoint kinase 1 (Chk1) protects vertebrate cells against merotelic attachments and lagging chromosomes and is required for correction of merotelic attachments during a prolonged metaphase. Decreased Chk1 activity leads to hyper-stable kinetochore microtubules, unstable binding of MCAK, Kif2b and Mps1 to centromeres or kinetochores and reduced phosphorylation of Hec1 by Aurora-B. Phosphorylation of Aurora-B at serine 331 (Ser331) by Chk1 is high in prometaphase and decreases significantly in metaphase cells. We propose that Ser331 phosphorylation is required for optimal localization of MCAK, Kif2b and Mps1 to centromeres or kinetochores and for Hec1 phosphorylation. Furthermore, inhibition of Mps1 activity diminishes initial recruitment of MCAK and Kif2b to centromeres or kinetochores, impairs Hec1 phosphorylation and exacerbates merotelic attachments in Chk1-deficient cells. We propose that Chk1 and Mps1 jointly regulate Aurora-B, MCAK, Kif2b and Hec1 to correct merotelic attachments. These results suggest a role for Chk1 and Mps1 in error correction.

Why do Families of Sick Newborns Accept Hospital Care? A Community-Based Cohort Study in Karachi, Pakistan

PubMed Central

Owais, Aatekah; Sultana, Shazia; Stein, Aryeh D.; Bashir, Nasira H.; Awaldad, Razia; Zaidi, Anita K M

2011-01-01

Objective Sick young infants are at high risk of mortality in developing countries but families often decline hospital referral. Our objective was to identify the predictors of acceptance of referral for hospital care among families of severely ill newborns and infants <59 days old in three low-income communities of Karachi, Pakistan. Study design A cohort of 541 newborns and infants referred from home by community health workers doing household surveillance, and diagnosed with a serious illness at local community clinics between January 1 and December 31, 2007, was followed-up within 1 month of referral to the public hospital. Results Only 24% of families accepted hospital referral. Major reasons for refusal were financial difficulties (67%) and father/elder denying permission (65%). Religious/cultural beliefs were cited by 20% of families. Referral acceptance was higher with recognition of severity of the illness by mother (OR=12.7; 95% CI=4.6–35.2), family’s ability to speak the dominant language at hospital (OR=2.0; 95% CI=1.3–3.1), presence of grunting in the infant (OR=3.3; 95% CI=1.2–9.0), and infant temperature <35.5°C (OR=4.1; 95% CI=2.3–7.4). No gender differential was observed. Conclusion Refusal of hospital referral for sick young infants is very common. Interventions that encourage appropriate care seeking, as well as community-based management of young infant illnesses when referral is not feasible are needed to improve neonatal survival in low-income countries. PMID:21273989

The ATM and Rad3-Related (ATR) Protein Kinase Pathway Is Activated by Herpes Simplex Virus 1 and Required for Efficient Viral Replication.

PubMed

Edwards, Terri G; Bloom, David C; Fisher, Chris

2018-03-15

The ATM and Rad3-related (ATR) protein kinase and its downstream effector Chk1 are key sensors and organizers of the DNA damage response (DDR) to a variety of insults. Previous studies of herpes simplex virus 1 (HSV-1) showed no evidence for activation of the ATR pathway. Here we demonstrate that both Chk1 and ATR were phosphorylated by 3 h postinfection (h.p.i.). Activation of ATR and Chk1 was observed using 4 different HSV-1 strains in multiple cell types, while a specific ATR inhibitor blocked activation. Mechanistic studies point to early viral gene expression as a key trigger for ATR activation. Both pATR and pChk1 localized to the nucleus within viral replication centers, or associated with their periphery, by 3 h.p.i. Significant levels of pATR and pChk1 were also detected in the cytoplasm, where they colocalized with ICP4 and ICP0. Proximity ligation assays confirmed that pATR and pChk1 were closely and specifically associated with ICP4 and ICP0 in both the nucleus and cytoplasm by 3 h.p.i., but not with ICP8 or ICP27, presumably in a multiprotein complex. Chemically distinct ATR and Chk1 inhibitors blocked HSV-1 replication and infectious virion production, while inhibitors of ATM, Chk2, and DNA-dependent protein kinase (DNA-PK) did not. Together our data show that HSV-1 activates the ATR pathway at early stages of infection and that ATR and Chk1 kinase activities play important roles in HSV-1 replication fitness. These findings indicate that the ATR pathway may provide insight for therapeutic approaches. IMPORTANCE Viruses have evolved complex associations with cellular DNA damage response (DDR) pathways, which sense troublesome DNA structures formed during infection. The first evidence for activation of the ATR pathway by HSV-1 is presented. ATR is activated, and its downstream target Chk1 is robustly phosphorylated, during early stages of infection. Both activated proteins are found in the nucleus associated with viral replication compartments and in the cytoplasm associated with viral proteins. We also demonstrate that both ATR and Chk1 kinase activities are important for viral replication. The findings suggest that HSV-1 activates ATR and Chk1 during early stages of infection and utilizes the enzymes to promote its own replication. The observation may be exploitable for antiviral approaches. Copyright © 2018 American Society for Microbiology.

Health-seeking behaviour of people living with HIV/AIDS and their satisfaction with health services provided at a tertiary care hospital, Karachi, Pakistan.

PubMed

Bhutto, Abdul-Qadir; Nisar, Nighat

2017-02-21

Appropriate health-seeking behaviour is important as it allows prompt treatment for a condition and this can reduce complications and improve quality of life. This study aimed to assess the health-seeking behaviour and satisfaction with health care services of people living with HIV/AIDS attending the HIV/AIDS clinic of the Civil Hospital in Karachi. A total of 182 patients were interviewed using a pretested semi-structured questionnaire. Mean age of the participants was 32.31 (SD 7.91) years, 76.9% were male, 81.3% had no education and 75.8% were employed. Only 23.6% showed positive health-seeking behaviour and 57.7% were satisfied with the health care services. In logistic regression analysis, the cost of treatment per visit < US$ 5 and duration of HIV infection < 2 years were significantly associated with health-seeking behaviour. Efforts are needed to improve the health-seeking behaviour of people living with HIV/AIDS at the clinic and the health services offered.

Dyslipidaemia in woman with polycystic ovarian syndrome: a case control study in tertiary care hospital of Karachi.

PubMed

Hussain, Amna; Alam, Junaid Mahmood

2014-09-01

To compare lipid profile in lean and obese women with polycystic ovary syndrome with normal weight and obese controls. The case-control study was conducted at the Department of Chemical Pathology, Liaquat National Hospital, Karachi, from March 2006 to April 2007. It comprised 50 cases of polycystic ovary syndrome along with 50 healthy controls matching for age, gender and weight. SPSS 14 was used for statistical analysis. The mean fasting levels of triglyceride and Low density lipoprotein cholesterol were considerably higher in women with polycystic ovary syndrome than those in the control group (p < 0.05), while high-density lipoprotein cholesterolwas significantly low in patients than the controls (p <0.001). Obese patients had high triglyceride value (p < 0.05). There was significant interaction between polycystic ovary syndrome, obesity and triglyceride levels (p < 0.05). Polycystic ovary syndrome is associated with a more pronounced atherogenic lipid profile. Lipid parameters were adversely affected in a subgroup that was obese. As such, women with polycystic ovary syndrome are at high risk of developing cardiovascular disease due to the presence of dyslipidaemia.

Frequency of Magnetic Resonance Imaging patterns of tuberculous spondylitis in a public sector hospital.

PubMed

Tabassum, Sumera; Haider, Shahbaz

2016-01-01

To determine frequencies of different MRI patterns of tuberculous spondylitisin a public sector hospital in Karachi. This descriptive multidisciplinary case series study was done from October 25, 2011 to May 28, 2012 in Radiology Department and Department of Medicine in the Jinnah Postgraduate Medical Center Karachi. MRI scans (dorsal / lumbosacral spine) of the Patients presenting with backache in Medical OPD, were performed in Radiology Department. Axial and sagittal images of T1 weighted, T2 weighted and STIR sequences of the affected region were taken. A total of 140 patients who were diagnosed as having tuberculous spondylitis were further evaluated and analyzed for having different patterns of involvement of the spine and compared with similar studies. Among frequencies of different MRI pattern of tuberculous spondylitis, contiguous vertebral involvement was 100%, discal involvement 98.6%, paravertebral abscess 92.1% cases, epidural abscess 91.4%, spinal cord / thecal sac compression 89.3%, vertebral collapse 72.9%, gibbus deformity 42.9% and psoas abscess 36.4%. Contiguous vertebral involvement was commonest MRI pattern, followed by disk involvement, paravertebral & epidural abscesses, thecal sac compression and vertebral collapse.

Current trends in treatment of hypertension in Karachi and cost minimization possibilities.

PubMed

Hussain, Izhar M; Naqvi, Baqir S; Qasim, Rao M; Ali, Nasir

2015-01-01

This study finds out drug usage trends in Stage I Hypertensive Patients without any compelling indications in Karachi, deviations of current practices from evidence based antihypertensive therapeutic guidelines and looks for cost minimization opportunities. In the present study conducted during June 2012 to August 2012, two sets were used. Randomized stratified independent surveys were conducted in doctors and general population - including patients, using pretested questionnaires. Sample sizes for doctors and general population were 100 and 400 respectively. Statistical analysis was conducted on Statistical Package for Social Science (SPSS). Financial impact was also analyzed. On the basis of patients' doctors' feedback, Beta Blockers, and Angiotensin Converting Enzyme Inhibitors were used more frequently than other drugs. Thiazides and low-priced generics were hardly prescribed. Beta blockers were prescribed widely and considered cost effective. This trend increases cost by two to ten times. Feedbacks showed that therapeutic guidelines were not followed by the doctors practicing in the community and hospitals in Karachi. Thiazide diuretics were hardly used. Beta blockers were widely prescribed. High priced market leaders or expensive branded generics were commonly prescribed. Therefore, there are great opportunities for cost minimization by using evidence-based clinically effective and safe medicines.

Chk1 promotes replication fork progression by controlling replication initiation

PubMed Central

Petermann, Eva; Woodcock, Mick; Helleday, Thomas

2010-01-01

DNA replication starts at initiation sites termed replication origins. Metazoan cells contain many more potential origins than are activated (fired) during each S phase. Origin activation is controlled by the ATR checkpoint kinase and its downstream effector kinase Chk1, which suppresses origin firing in response to replication blocks and during normal S phase by inhibiting the cyclin-dependent kinase Cdk2. In addition to increased origin activation, cells deficient in Chk1 activity display reduced rates of replication fork progression. Here we investigate the causal relationship between increased origin firing and reduced replication fork progression. We use the Cdk inhibitor roscovitine or RNAi depletion of Cdc7 to inhibit origin firing in Chk1-inhibited or RNAi-depleted cells. We report that Cdk inhibition and depletion of Cdc7 can alleviate the slow replication fork speeds in Chk1-deficient cells. Our data suggest that increased replication initiation leads to slow replication fork progression and that Chk1 promotes replication fork progression during normal S phase by controlling replication origin activity. PMID:20805465

Distinct but Concerted Roles of ATR, DNA-PK, and Chk1 in Countering Replication Stress during S Phase

PubMed Central

Buisson, Rémi; Boisvert, Jessica L.; Benes, Cyril H.; Zou, Lee

2015-01-01

The ATR-Chk1 pathway is critical for DNA damage responses and cell cycle progression. Chk1 inhibition is more deleterious to cycling cells than ATR inhibition, raising questions about ATR and Chk1 functions in the absence of extrinsic replication stress. Here, we show that a key role of ATR in S phase is to coordinate RRM2 accumulation and origin firing. ATR inhibitor (ATRi) induces massive ssDNA accumulation and replication catastrophe in a fraction of early S-phase cells. In other S-phase cells, however, ATRi induces moderate ssDNA and triggers a DNA-PK and Chk1-mediated backup pathway to suppress origin firing. The backup pathway creates a threshold such that ATRi selectively kills cells under high replication stress, whereas Chk1 inhibitor induces cell death at a lower threshold. The levels of ATRi-induced ssDNA correlate with ATRi sensitivity in a panel of cell lines, suggesting that ATRi-induced ssDNA could be predictive of ATRi sensitivity in cancer cells. PMID:26365377

Genotoxic stress-induced activation of Plk3 is partly mediated by Chk2.

PubMed

Xie, Suqing; Wu, Huiyun; Wang, Qi; Kunicki, Jan; Thomas, Raymond O; Hollingsworth, Robert E; Cogswell, John; Dai, Wei

2002-01-01

Polo-like kinase 3 (Plk3, alternatively termed Prk) is involved in the regulation of DNA damage checkpoint as well as in M-phase function. Plk3 physically interacts with p53 and phosphorylates this tumor suppressor protein on serine-20, suggesting that the role of Plk3 in cell cycle progression is mediated, at least in part, through direct regulation of p53. Here we show that Plk3 is rapidly activated by reactive oxygen species in normal diploid fibroblast cells (WI-38), correlating with a subsequent increase in p53 protein level. Plk3 physically interacts with Chk2 and the interaction is enhanced upon DNA damage. In addition, Chk2 immunoprecipitated from cell lysates of Daudi (which expressed little Plk3) is capable of stimulating the kinase activity of purified recombinant Plk3 in vitro, and this stimulation is more pronounced when Plk3 is supplemented with Chk2 immunoprecipitated from Daudi after DNA damage. Furthermore, ectopic expression Chk2 activates cellular Plk3. Together, our studies suggest Chk2 may mediate direct activation of Plk3 in response to genotoxic stresses.

Chk1 Promotes DNA Damage Response Bypass following Oxidative Stress in a Model of Hydrogen Peroxide-Associated Ulcerative Colitis through JNK Inactivation and Chromatin Binding.

PubMed

Reissig, Kathrin; Silver, Andrew; Hartig, Roland; Schinlauer, Antje; Walluscheck, Diana; Guenther, Thomas; Siedentopf, Sandra; Ross, Jochen; Vo, Diep-Khanh; Roessner, Albert; Poehlmann-Nitsche, Angela

2017-01-01

Dysregulation of c-Jun N -terminal kinase (JNK) activation promoted DNA damage response bypass and tumorigenesis in our model of hydrogen peroxide-associated ulcerative colitis (UC) and in patients with quiescent UC (QUC), UC-related dysplasia, and UC-related carcinoma (UC-CRC), thereby adapting to oxidative stress. In the UC model, we have observed features of oncogenic transformation: increased proliferation, undetected DNA damage, and apoptosis resistance. Here, we show that Chk1 was downregulated but activated in the acute and quiescent chronic phases. In both phases, Chk1 was linked to DNA damage response bypass by suppressing JNK activation following oxidative stress, promoting cell cycle progression despite DNA damage. Simultaneously, activated Chk1 was bound to chromatin. This triggered histone acetylation and the binding of histone acetyltransferases and transcription factors to chromatin. Thus, chromatin-immobilized activated Chk1 executed a dual function by suppressing DNA damage response and simultaneously inducing chromatin modulation. This caused undetected DNA damage and increased cellular proliferation through failure to transmit the appropriate DNA damage signal. Findings in vitro were corroborated by chromatin accumulation of activated Chk1, Ac-H3, Ac-H4, and c-Jun in active UC (AUC) in vivo. Targeting chromatin-bound Chk1, GCN5, PCAF, and p300/CBP could be a novel therapeutic strategy to prevent UC-related tumor progression.

A university-sponsored home health nursing program in Karachi, Pakistan.

PubMed

Smego, Raymond A; Khan, Mohammad Aslam; Khowaja, Khurshid; Rafique, Rozina; Datoo, Farida

2005-11-01

This article describes a university-sponsored home health nursing program in a large urban center in Pakistan and details the essential elements needed in implementing such a program in a developing country. Compared to in-hospital treatment, home healthcare reduced hospital stay from 12.8 days to 3.9 days, and resulted in a net savings of Pakistani rupees (PRs) 5,374,135 (USD 89,569). A cost-effective home treatment program in a resource-limited country can be successfully implemented by using the hospital pharmacy as the central point for the preparation and distribution of medications and specialty nursing services.

Cytokinetically quiescent (G0/G1) human multiple myeloma cells are susceptible to simultaneous inhibition of Chk1 and MEK1/2

PubMed Central

Pei, Xin-Yan; Dai, Yun; Youssefian, Leena E.; Chen, Shuang; Bodie, Wesley W.; Takabatake, Yukie; Felthousen, Jessica; Almenara, Jorge A.; Kramer, Lora B.; Dent, Paul

2011-01-01

Effects of Chk1 and MEK1/2 inhibition were investigated in cytokinetically quiescent multiple myeloma (MM) and primary CD138+ cells. Coexposure to the Chk1 and MEK1/2 inhibitors AZD7762 and selumetinib (AZD6244) robustly induced apoptosis in various MM cells and CD138+ primary samples, but spared normal CD138− and CD34+ cells. Furthermore, Chk1/MEK1/2 inhibitor treatment of asynchronized cells induced G0/G1 arrest and increased apoptosis in all cell-cycle phases, including G0/G1. To determine whether this regimen is active against quiescent G0/G1 MM cells, cells were cultured in low-serum medium to enrich the G0/G1 population. G0/G1–enriched cells exhibited diminished sensitivity to conventional agents (eg, Taxol and VP-16) but significantly increased susceptibility to Chk1 ± MEK1/2 inhibitors or Chk1 shRNA knock-down. These events were associated with increased γH2A.X expression/foci formation and Bim up-regulation, whereas Bim shRNA knock-down markedly attenuated lethality. Immunofluorescent analysis of G0/G1–enriched or primary MM cells demonstrated colocalization of activated caspase-3 and the quiescent (G0) marker statin, a nuclear envelope protein. Finally, Chk1/MEK1/2 inhibition increased cell death in the Hoechst-positive (Hst+), low pyronin Y (PY)–staining (2N Hst+/PY−) G0 population and in sorted small side-population (SSP) MM cells. These findings provide evidence that cytokinetically quiescent MM cells are highly susceptible to simultaneous Chk1 and MEK1/2 inhibition. PMID:21911831

Cytokinetically quiescent (G0/G1) human multiple myeloma cells are susceptible to simultaneous inhibition of Chk1 and MEK1/2.

PubMed

Pei, Xin-Yan; Dai, Yun; Youssefian, Leena E; Chen, Shuang; Bodie, Wesley W; Takabatake, Yukie; Felthousen, Jessica; Almenara, Jorge A; Kramer, Lora B; Dent, Paul; Grant, Steven

2011-11-10

Effects of Chk1 and MEK1/2 inhibition were investigated in cytokinetically quiescent multiple myeloma (MM) and primary CD138(+) cells. Coexposure to the Chk1 and MEK1/2 inhibitors AZD7762 and selumetinib (AZD6244) robustly induced apoptosis in various MM cells and CD138(+) primary samples, but spared normal CD138(-) and CD34(+) cells. Furthermore, Chk1/MEK1/2 inhibitor treatment of asynchronized cells induced G(0)/G(1) arrest and increased apoptosis in all cell-cycle phases, including G(0)/G(1). To determine whether this regimen is active against quiescent G(0)/G(1) MM cells, cells were cultured in low-serum medium to enrich the G(0)/G(1) population. G(0)/G(1)-enriched cells exhibited diminished sensitivity to conventional agents (eg, Taxol and VP-16) but significantly increased susceptibility to Chk1 ± MEK1/2 inhibitors or Chk1 shRNA knock-down. These events were associated with increased γH2A.X expression/foci formation and Bim up-regulation, whereas Bim shRNA knock-down markedly attenuated lethality. Immunofluorescent analysis of G(0)/G(1)-enriched or primary MM cells demonstrated colocalization of activated caspase-3 and the quiescent (G(0)) marker statin, a nuclear envelope protein. Finally, Chk1/MEK1/2 inhibition increased cell death in the Hoechst-positive (Hst(+)), low pyronin Y (PY)-staining (2N Hst(+)/PY(-)) G(0) population and in sorted small side-population (SSP) MM cells. These findings provide evidence that cytokinetically quiescent MM cells are highly susceptible to simultaneous Chk1 and MEK1/2 inhibition.

Undergraduate radiology education in private and public teaching hospitals in Karachi, Pakistan: teaching duties, methodologies, and rewards

PubMed Central

Nadeem, Naila; Khawaja, Ranish Deedar Ali; Beg, Madiha; Naeem, Muhammad; Majid, Zain

2013-01-01

Background In an integrated method of education, medical students are introduced to radiology in their preclinical years. However, no study has been conducted in Pakistan to demonstrate an academic framework of medical radiology education at an undergraduate level. Therefore, we aimed to document and compare the current level of teaching duties, teaching methodologies, and teaching rewards among radiologists and residents in private and public teaching hospitals in Karachi, Pakistan. Methods A survey was conducted among 121 radiologists and residents in two private and two public teaching hospitals in Karachi, Pakistan. Radiologists who were nationally registered with the Pakistan Medical and Dental Council either part-time or full-time were included. Radiology residents and fellows who were nationally registered with the Pakistan Medical and Dental Council were also included. Self-administered questionnaires addressing teaching duties, methods, and rewards were collected from 95 participants. Results The overall response rate was 78.51% (95/121). All of the radiologists were involved in teaching residents and medical students, but only 36% reported formal training in teaching skills. Although most of the respondents (76%) agreed that medical students appeared enthusiastic about learning radiology, the time spent on teaching medical students was less than five hours per week annually (82%). Only 37% of the respondents preferred dedicated clerkships over distributed clerkships (41%). The most common preferred teaching methodology overall was one-on-one interaction. Tutorials, teaching rounds, and problem-based learning sessions were less favored by radiologists than by residents. Teaching via radiology films (86%) was the most frequent mode of instruction. Salary (59%) was the most commonly cited teaching reward. The majority of respondents (88%) were not satisfied with their current level of teaching rewards. Conclusion All radiologists and residents working in an academic radiology department are involved in teaching undergraduate students at multiple levels. The most valued teaching methodology involves use of images, with one-on-one interaction between the trainer and trainee. The monetary reward for teaching is inbuilt into the salary. The methodology adopted for teaching purposes was significantly different between respondents from private hospitals and those from public teaching hospitals. Because of low satisfaction among the respondents, efforts should be made to provide satisfying teaching rewards. PMID:23745098

SMK-1/PPH-4.1–mediated silencing of the CHK-1 response to DNA damage in early C. elegans embryos

PubMed Central

Kim, Seung-Hwan; Holway, Antonia H.; Wolff, Suzanne; Dillin, Andrew; Michael, W. Matthew

2007-01-01

During early embryogenesis in Caenorhabditis elegans, the ATL-1–CHK-1 (ataxia telangiectasia mutated and Rad3 related–Chk1) checkpoint controls the timing of cell division in the future germ line, or P lineage, of the animal. Activation of the CHK-1 pathway by its canonical stimulus DNA damage is actively suppressed in early embryos so that P lineage cell divisions may occur on schedule. We recently found that the rad-2 mutation alleviates this checkpoint silent DNA damage response and, by doing so, causes damage-dependent delays in early embryonic cell cycle progression and subsequent lethality. In this study, we report that mutations in the smk-1 gene cause the rad-2 phenotype. SMK-1 is a regulatory subunit of the PPH-4.1 (protein phosphatase 4) protein phosphatase, and we show that SMK-1 recruits PPH-4.1 to replicating chromatin, where it silences the CHK-1 response to DNA damage. These results identify the SMK-1–PPH-4.1 complex as a critical regulator of the CHK-1 pathway in a developmentally relevant context. PMID:17908915

Chk1 Promotes DNA Damage Response Bypass following Oxidative Stress in a Model of Hydrogen Peroxide-Associated Ulcerative Colitis through JNK Inactivation and Chromatin Binding

PubMed Central

Silver, Andrew; Guenther, Thomas; Siedentopf, Sandra; Ross, Jochen; Vo, Diep-Khanh; Roessner, Albert

2017-01-01

Dysregulation of c-Jun N-terminal kinase (JNK) activation promoted DNA damage response bypass and tumorigenesis in our model of hydrogen peroxide-associated ulcerative colitis (UC) and in patients with quiescent UC (QUC), UC-related dysplasia, and UC-related carcinoma (UC-CRC), thereby adapting to oxidative stress. In the UC model, we have observed features of oncogenic transformation: increased proliferation, undetected DNA damage, and apoptosis resistance. Here, we show that Chk1 was downregulated but activated in the acute and quiescent chronic phases. In both phases, Chk1 was linked to DNA damage response bypass by suppressing JNK activation following oxidative stress, promoting cell cycle progression despite DNA damage. Simultaneously, activated Chk1 was bound to chromatin. This triggered histone acetylation and the binding of histone acetyltransferases and transcription factors to chromatin. Thus, chromatin-immobilized activated Chk1 executed a dual function by suppressing DNA damage response and simultaneously inducing chromatin modulation. This caused undetected DNA damage and increased cellular proliferation through failure to transmit the appropriate DNA damage signal. Findings in vitro were corroborated by chromatin accumulation of activated Chk1, Ac-H3, Ac-H4, and c-Jun in active UC (AUC) in vivo. Targeting chromatin-bound Chk1, GCN5, PCAF, and p300/CBP could be a novel therapeutic strategy to prevent UC-related tumor progression. PMID:28751935

Discovery of a novel class of triazolones as checkpoint kinase inhibitors--hit to lead exploration.

PubMed

Oza, Vibha; Ashwell, Susan; Brassil, Patrick; Breed, Jason; Deng, Chun; Ezhuthachan, Jay; Haye, Heather; Horn, Candice; Janetka, James; Lyne, Paul; Newcombe, Nicholas; Otterbien, Ludo; Pass, Martin; Read, Jon; Roswell, Sian; Su, Mei; Toader, Dorin; Yu, Dingwei; Yu, Yan; Valentine, Anna; Webborn, Peter; White, Ann; Zabludoff, Sonya; Zheng, Xiaolan

2010-09-01

Checkpoint Kinase-1 (Chk1, CHK1, CHEK1) is a Ser/Thr protein kinase that mediates cellular responses to DNA-damage. A novel class of Chk1 inhibitors, triazoloquinolones/triazolones (TZ's) was identified by high throughput screening. The optimization of these hits to provide a lead series is described. Copyright 2010 Elsevier Ltd. All rights reserved.

Chk1 inhibition activates p53 through p38 MAPK in tetraploid cancer cells.

PubMed

Vitale, Ilio; Senovilla, Laura; Galluzzi, Lorenzo; Criollo, Alfredo; Vivet, Sonia; Castedo, Maria; Kroemer, Guido

2008-07-01

We have previously shown that tetraploid cancer cells succumb through a p53-dependent apoptotic pathway when checkpoint kinase 1 (Chk1) is depleted by small interfering RNAs (siRNAs) or inhibited with 7-hydroxystaurosporine (UCN-01). Here, we demonstrate that Chk1 inhibition results in the activating phosphorylation of p38 mitogen-activated protein kinase (p38 MAPK). Depletion of p38 MAPK by transfection with a siRNA targeting the alpha isoform of p38 MAPK (p38alpha MAPK) abolishes the phosphorylation of p53 on serines 15 and 46 that is induced by Chk1 knockdown. The siRNA-mediated downregulation and pharmacological inhibition of p38alpha MAPK (with SB 203580) also reduces cell death induced by Chk1 knockdown or UCN-01. These results underscore the role of p38 MAPK as a pro-apoptotic kinase in the p53-dependant pathway for the therapeutic elimination of polyploidy cells.

A Functional Approach Reveals a Genetic and Physical Interaction between Ribonucleotide Reductase and CHK1 in Mammalian Cells

PubMed Central

Taricani, Lorena; Shanahan, Frances; Malinao, Maria-Christina; Beaumont, Maribel; Parry, David

2014-01-01

Ribonucleotide reductase (RNR) enzyme is composed of the homodimeric RRM1 and RRM2 subunits, which together form a heterotetramic active enzyme that catalyzes the de novo reduction of ribonucleotides to generate deoxyribonucleotides (dNTPs), which are required for DNA replication and DNA repair processes. In this study, we show that ablation of RRM1 and RRM2 by siRNA induces G1/S phase arrest, phosphorylation of Chk1 on Ser345 and phosphorylation of γ-H2AX on S139. Combinatorial ablation of RRM1 or RRM2 and Chk1 causes a dramatic accumulation of γ-H2AX, a marker of double-strand DNA breaks, suggesting that activation of Chk1 in this context is essential for suppression of DNA damage. Significantly, we demonstrate for the first time that Chk1 and RNR subunits co-immunoprecipitate from native cell extracts. These functional genomic studies suggest that RNR is a critical mediator of replication checkpoint activation. PMID:25375241

Activation of checkpoint kinase 2 is critical for herpes simplex virus type 1 replication in corneal epithelium.

PubMed

Alekseev, Oleg; Limonnik, Vladimir; Donovan, Kelly; Azizkhan-Clifford, Jane

2015-01-01

Herpes simplex virus (HSV) type I keratitis remains a leading cause of corneal morbidity, despite the availability of effective antiviral drugs. Improved understanding of virus-host interactions at the level of the host DNA damage response (DDR), a known factor in the development of HSV-1 keratitis, may shed light on potential new therapeutic targets. This report examines the role of checkpoint kinase 2 (Chk2), a DDR mediator protein, in corneal epithelial HSV-1 infection. A small-molecule inhibitor of Chk2 (Chk2 inhibitor II) was applied to HSV-1-infected cultured human corneal epithelial cells (hTCEpi and HCE) as well as to explanted and organotypically cultured human and rabbit corneas. Infection levels were assessed by plaque assay and real-time PCR. RNAi-mediated depletion of Chk2 was performed to confirm the effect of the inhibitor. Inhibition of the Chk2 kinase activity greatly suppresses the cytopathic effect, genome replication and infectious progeny production in vitro and ex vivo. This report demonstrates the critical role of Chk2 kinase in the establishment of HSV-1 corneal epithelial infection. These data contribute to our understanding of herpesvirus-host interactions and underscore the significance of DDR activation in HSV-1 keratitis.

Pattern of Injuries from Road Traffic Accidents Presented at a Rural Teaching Institution of Karachi.

PubMed

Shamim, Muhammad

2017-08-01

The aim of the study is to study the pattern of injuries from road traffic accidents presented at the emergency department of a rural teaching institution in Karachi. This descriptive case series was conducted prospectively in the Emergency Department of Fatima Hospital and Baqai Medical University from 1 January 2012 to 21 March 2013. There were 385 patients in the series. All of the patients with recent injuries from road traffic accidents were included. Cases with injuries more than 72 h old were excluded. The majority of patients had lower limb injuries 172 (44.7%), followed by head and neck injuries 107 (27.8%), multiple injuries 62 (16.1%), upper limb injuries 22 (5.7%), abdominoperineal injuries 19 (5%), and chest injuries 3 (0.8%). Majority (229, 59.5%) of patients were given first aid treatment and discharged, while 151 (39.3%) patients were either admitted or referred to better equipped hospitals. Three patients were brought dead, and two patients left against medical advice. The lower limb injuries were the commonest road traffic accidental injuries, followed by head and neck injuries, multiple injuries, upper limb injuries, abdominoperineal injuries, and chest injuries.

How close are we? An audit of biometry of a tertiary care hospital in Karachi.

PubMed

Siddiqui, Abdul Hameed; Khan, Maria; Hussain, Marium

2018-01-01

To evaluate the accuracy of biometry in the post-op phase of cataract surgery. This study was conducted at Liaquat National Hospital, Karachi, from June 2015 to July 2016, and comprised the audit of patients who underwent cataract surgery during the period. Keratometry was done on Haag-Strait manual keratometer and A-scan was done by applanation contact method on SonoMed machine. Theoretic-T formula was used to calculate desired intraocular lens power for all kinds of axial lengths. A single surgeon operated upon the same Alcon Constellation phacoemulsification machine. Postoperative follow-up was done by monitoring auto refraction and visual acuity on days 1, 7, 30 and 90. SPSS 21 was used for data analysis.. Of 244 patients, 121(49.60%) were males and 123(50.40%) were females. There were 123(50.40%) right eyes and 121(49.60%) left eyes. Overall, 132(54.10%) achieved postoperative refraction within ±0.5 D of target and 193(79.10%) within ±1 D of target. Age, gender and laterality had no significant effect on outcomes (p>0.05 each). Postoperative refraction corresponded quite closely with global recommendations.

Frequency of Magnetic Resonance Imaging patterns of tuberculous spondylitis in a public sector hospital

PubMed Central

Tabassum, Sumera; Haider, Shahbaz

2016-01-01

Objective: To determine frequencies of different MRI patterns of tuberculous spondylitisin a public sector hospital in Karachi. Methods: This descriptive multidisciplinary case series study was done from October 25, 2011 to May 28, 2012 in Radiology Department and Department of Medicine in the Jinnah Postgraduate Medical Center Karachi. MRI scans (dorsal / lumbosacral spine) of the Patients presenting with backache in Medical OPD, were performed in Radiology Department. Axial and sagittal images of T1 weighted, T2 weighted and STIR sequences of the affected region were taken. A total of 140 patients who were diagnosed as having tuberculous spondylitis were further evaluated and analyzed for having different patterns of involvement of the spine and compared with similar studies. Results: Among frequencies of different MRI pattern of tuberculous spondylitis, contiguous vertebral involvement was 100%, discal involvement 98.6%, paravertebral abscess 92.1% cases, epidural abscess 91.4%, spinal cord / thecal sac compression 89.3%, vertebral collapse 72.9%, gibbus deformity 42.9% and psoas abscess 36.4%. Conclusion: Contiguous vertebral involvement was commonest MRI pattern, followed by disk involvement, paravertebral & epidural abscesses, thecal sac compression and vertebral collapse. PMID:27022369

Chk1 inhibition potentiates the therapeutic efficacy of PARP inhibitor BMN673 in gastric cancer

PubMed Central

Yin, Yuping; Shen, Qian; Zhang, Peng; Tao, Ruikang; Chang, Weilong; Li, Ruidong; Xie, Gengchen; Liu, Weizhen; Zhang, Lihong; Kapoor, Prabodh; Song, Shumei; Ajani, Jaffer; Mills, Gordon B; Chen, Jianying; Tao, Kaixiong; Peng, Guang

2017-01-01

Globally, gastric cancer is the second leading cause of cancer deaths because of the lack of effective treatments for patients with advanced tumors when curative surgery is not possible. Thus, there is an urgent need to identify molecular targets in gastric cancer that can be used for developing novel therapies and prolonging patient survival. Checkpoint kinase 1 (Chk1) is a crucial regulator of cell cycle transition in DNA damage response (DDR). In our study, we report that Chk1 plays an important role in promoting gastric cancer cell survival and growth, which serves as an effective therapeutic target in gastric cancer. First, Chk1 ablation by small interfering RNA could significantly inhibit cell proliferation and sensitize the effects of ionizing radiation (IR) treatment in both p53 wild type gastric cancer cell line AGS, and p53 mutant cell line MKN1. Secondly, we tested the anticancer effects of Chk1 chemical inhibitor LY2606368, which is a novel Chk1/2 targeted drug undergoing clinical trials in many malignant diseases. We found that LY2606368 can induce DNA damage, and remarkably suppress cancer proliferation and induce apoptosis in AGS and MKN1 cells. Moreover, we identified that LY2606368 can significantly inhibit homologous recombination (HR) mediated DNA repair and thus showed marked synergistic anticancer effect in combination with poly (ADP-ribose) polymerase 1 (PARP1) inhibitor BMN673 in both in vitro studies and in vivo experiments using a gastric cancer PDx model. The synergy between LY2606368 and PARP1 was likely caused by impaired the G2M checkpoint due to LY2606368 treatment, which forced mitotic entry and cell death in the presence of BMN673. In conclusion, we propose that Chk1 is a valued target for gastric cancer treatment, especially Chk1 inhibitor combined with PARP inhibitor may be a more effective therapeutic strategy in gastric cancer. PMID:28401005

Synthetic lethal RNAi screening identifies sensitizing targets for gemcitabine therapy in pancreatic cancer

PubMed Central

Azorsa, David O; Gonzales, Irma M; Basu, Gargi D; Choudhary, Ashish; Arora, Shilpi; Bisanz, Kristen M; Kiefer, Jeffrey A; Henderson, Meredith C; Trent, Jeffrey M; Von Hoff, Daniel D; Mousses, Spyro

2009-01-01

Background Pancreatic cancer retains a poor prognosis among the gastrointestinal cancers. It affects 230,000 individuals worldwide, has a very high mortality rate, and remains one of the most challenging malignancies to treat successfully. Treatment with gemcitabine, the most widely used chemotherapeutic against pancreatic cancer, is not curative and resistance may occur. Combinations of gemcitabine with other chemotherapeutic drugs or biological agents have resulted in limited improvement. Methods In order to improve gemcitabine response in pancreatic cancer cells, we utilized a synthetic lethal RNAi screen targeting 572 known kinases to identify genes that when silenced would sensitize pancreatic cancer cells to gemcitabine. Results Results from the RNAi screens identified several genes that, when silenced, potentiated the growth inhibitory effects of gemcitabine in pancreatic cancer cells. The greatest potentiation was shown by siRNA targeting checkpoint kinase 1 (CHK1). Validation of the screening results was performed in MIA PaCa-2 and BxPC3 pancreatic cancer cells by examining the dose response of gemcitabine treatment in the presence of either CHK1 or CHK2 siRNA. These results showed a three to ten-fold decrease in the EC50 for CHK1 siRNA-treated cells versus control siRNA-treated cells while treatment with CHK2 siRNA resulted in no change compared to controls. CHK1 was further targeted with specific small molecule inhibitors SB 218078 and PD 407824 in combination with gemcitabine. Results showed that treatment of MIA PaCa-2 cells with either of the CHK1 inhibitors SB 218078 or PD 407824 led to sensitization of the pancreatic cancer cells to gemcitabine. Conclusion These findings demonstrate the effectiveness of synthetic lethal RNAi screening as a tool for identifying sensitizing targets to chemotherapeutic agents. These results also indicate that CHK1 could serve as a putative therapeutic target for sensitizing pancreatic cancer cells to gemcitabine. PMID:19519883

Opposing effects of pericentrin and microcephalin on the pericentriolar material regulate CHK1 activation in the DNA damage response.

PubMed

Antonczak, A K; Mullee, L I; Wang, Y; Comartin, D; Inoue, T; Pelletier, L; Morrison, C G

2016-04-14

Genotoxic stresses lead to centrosome amplification, a frequently-observed feature in cancer that may contribute to genome instability and to tumour cell invasion. Here we have explored how the centrosome controls DNA damage responses. For most of the cell cycle, centrosomes consist of two centrioles embedded in the proteinaceous pericentriolar material (PCM). Recent data indicate that the PCM is not an amorphous assembly of proteins, but actually a highly organised scaffold around the centrioles. The large coiled-coil protein, pericentrin, participates in PCM assembly and has been implicated in the control of DNA damage responses (DDRs) through its interactions with checkpoint kinase 1 (CHK1) and microcephalin (MCPH1). CHK1 is required for DNA damage-induced centrosome amplification, whereas MCPH1 deficiency greatly increases the amplification seen after DNA damage. We found that the PCM showed a marked expansion in volume and a noticeable change in higher-order organisation after ionising radiation treatment. PCM expansion was dependent on CHK1 kinase activity and was potentiated by MCPH1 deficiency. Furthermore, pericentrin deficiency or mutation of a separase cleavage site blocked DNA damage-induced PCM expansion. The extent of nuclear CHK1 activation after DNA damage reflected the level of PCM expansion, with a reduction in pericentrin-deficient or separase cleavage site mutant-expressing cells, and an increase in MCPH1-deficient cells that was suppressed by the loss of pericentrin. Deletion of the nuclear export signal of CHK1 led to its hyperphosphorylation after irradiation and reduced centrosome amplification. Deletion of the nuclear localisation signal led to low CHK1 activation and low centrosome amplification. From these data, we propose a feedback loop from the PCM to the nuclear DDR in which CHK1 regulates pericentrin-dependent PCM expansion to control its own activation.

Feedback regulation of methyl methanesulfonate and ultraviolet-sensitive gene clone 81 via ATM/Chk2 pathway contributes to the resistance of MCF-7 breast cancer cells to cisplatin.

PubMed

Lv, Juan; Qian, Ying; Ni, Xiaoyan; Xu, Xiuping; Dong, Xuejun

2017-03-01

The methyl methanesulfonate and ultraviolet-sensitive gene clone 81 protein is a structure-specific nuclease that plays important roles in DNA replication and repair. Knockdown of methyl methanesulfonate and ultraviolet-sensitive gene clone 81 has been found to sensitize cancer cells to chemotherapy. However, the underlying molecular mechanism is not well understood. We found that methyl methanesulfonate and ultraviolet-sensitive gene clone 81 was upregulated and the ATM/Chk2 pathway was activated at the same time when MCF-7 cells were treated with cisplatin. By using lentivirus targeting methyl methanesulfonate and ultraviolet-sensitive gene clone 81 gene, we showed that knockdown of methyl methanesulfonate and ultraviolet-sensitive gene clone 81 enhanced cell apoptosis and inhibited cell proliferation in MCF-7 cells under cisplatin treatment. Abrogation of ATM/Chk2 pathway inhibited cell viability in MCF-7 cells in response to cisplatin. Importantly, we revealed that ATM/Chk2 was required for the upregulation of methyl methanesulfonate and ultraviolet-sensitive gene clone 81, and knockdown of methyl methanesulfonate and ultraviolet-sensitive gene clone 81 resulted in inactivation of ATM/Chk2 pathway in response to cisplatin. Meanwhile, knockdown of methyl methanesulfonate and ultraviolet-sensitive gene clone 81 activated the p53/Bcl-2 pathway in response to cisplatin. These data suggest that the ATM/Chk2 may promote the repair of DNA damage caused by cisplatin by sustaining methyl methanesulfonate and ultraviolet-sensitive gene clone 81, and the double-strand breaks generated by methyl methanesulfonate and ultraviolet-sensitive gene clone 81 may activate the ATM/Chk2 pathway in turn, which provide a novel mechanism of how methyl methanesulfonate and ultraviolet-sensitive gene clone 81 modulates DNA damage response and repair.

Cell Density Affects the Detection of Chk1 Target Engagement by the Selective Inhibitor V158411.

PubMed

Geneste, Clara C; Massey, Andrew J

2018-02-01

Understanding drug target engagement and the relationship to downstream pharmacology is critical for drug discovery. Here we have evaluated target engagement of Chk1 by the small-molecule inhibitor V158411 using two different target engagement methods (autophosphorylation and cellular thermal shift assay [CETSA]). Target engagement measured by these methods was subsequently related to Chk1 inhibitor-dependent pharmacology. Inhibition of autophosphorylation was a robust method for measuring V158411 Chk1 target engagement. In comparison, while target engagement determined using CETSA appeared robust, the V158411 CETSA target engagement EC 50 values were 43- and 19-fold greater than the autophosphorylation IC 50 values. This difference was attributed to the higher cell density in the CETSA assay configuration. pChk1 (S296) IC 50 values determined using the CETSA assay conditions were 54- and 33-fold greater than those determined under standard conditions and were equivalent to the CETSA EC 50 values. Cellular conditions, especially cell density, influenced the target engagement of V158411 for Chk1. The effects of high cell density on apparent compound target engagement potency should be evaluated when using target engagement assays that necessitate high cell densities (such as the CETSA conditions used in this study). In such cases, the subsequent relation of these data to downstream pharmacological changes should therefore be interpreted with care.

Group X hybrid histidine kinase Chk1 is dispensable for stress adaptation, host-pathogen interactions and virulence in the opportunistic yeast Candida guilliermondii.

PubMed

Navarro-Arias, María J; Dementhon, Karine; Defosse, Tatiana A; Foureau, Emilien; Courdavault, Vincent; Clastre, Marc; Le Gal, Solène; Nevez, Gilles; Le Govic, Yohann; Bouchara, Jean-Philippe; Giglioli-Guivarc'h, Nathalie; Noël, Thierry; Mora-Montes, Hector M; Papon, Nicolas

2017-09-01

Hybrid histidine kinases (HHKs) progressively emerge as prominent sensing proteins in the fungal kingdom and as ideal targets for future therapeutics. The group X HHK is of major interest, since it was demonstrated to play an important role in stress adaptation, host-pathogen interactions and virulence in some yeast and mold models, and particularly Chk1, that corresponds to the sole group X HHK in Candida albicans. In the present work, we investigated the role of Chk1 in the low-virulence species Candida guilliermondii, in order to gain insight into putative conservation of the role of group X HHK in opportunistic yeasts. We demonstrated that disruption of the corresponding gene CHK1 does not influence growth, stress tolerance, drug susceptibility, protein glycosylation or cell wall composition in C. guilliermondii. In addition, we showed that loss of CHK1 does not affect C. guilliermondii ability to interact with macrophages and to stimulate cytokine production by human peripheral blood mononuclear cells. Finally, the C. guilliermondii chk1 null mutant was found to be as virulent as the wild-type strain in the experimental model Galleria mellonella. Taken together, our results demonstrate that group X HHK function is not conserved in Candida species. Copyright © 2017 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

Activation of DNA damage repair pathways by murine polyomavirus

DOE Office of Scientific and Technical Information (OSTI.GOV)

Heiser, Katie; Nicholas, Catherine; Garcea, Robert

Nuclear replication of DNA viruses activates DNA damage repair (DDR) pathways, which are thought to detect and inhibit viral replication. However, many DNA viruses also depend on these pathways in order to optimally replicate their genomes. We investigated the relationship between murine polyomavirus (MuPyV) and components of DDR signaling pathways including CHK1, CHK2, H2AX, ATR, and DNAPK. We found that recruitment and retention of DDR proteins at viral replication centers was independent of H2AX, as well as the viral small and middle T-antigens. Additionally, infectious virus production required ATR kinase activity, but was independent of CHK1, CHK2, or DNAPK signaling.more » ATR inhibition did not reduce the total amount of viral DNA accumulated, but affected the amount of virus produced, indicating a defect in virus assembly. These results suggest that MuPyV may utilize a subset of DDR proteins or non-canonical DDR signaling pathways in order to efficiently replicate and assemble. -- Highlights: •Murine polyomavirus activates and recruits DNA damage repair (DDR) proteins to replication centers. •Large T-antigen mediates recruitment of DDR proteins to viral replication centers. •Inhibition or knockout of CHK1, CHK2, DNA-PK or H2AX do not affect viral titers. •Inhibition of ATR activity reduces viral titers, but not viral DNA accumulation.« less

Development and pilot implementation of a locally developed Trauma Registry: lessons learnt in a low-income country.

PubMed

Mehmood, Amber; Razzak, Junaid Abdul; Kabir, Sarah; Mackenzie, Ellen J; Hyder, Adnan A

2013-03-21

Trauma registries (TRs) play an integral role in the assessment of trauma care quality. TRs are still uncommon in developing countries owing to awareness and cost. We present a case study of development and pilot implementation of "Karachi Trauma Registry" (KITR), using existing medical records at a tertiary-care hospital of Karachi, Pakistan to present results of initial data and describe its process of implementation. KITR is a locally developed, customized, electronic trauma registry based on open source software designed by local software developers in Karachi. Data for KITR was collected from November 2010 to January 2011. All patients presenting to the Emergency Department (ED) of the Aga Khan University Hospital (AKUH) with a diagnosis of injury as defined in ICD-9 CM were included. There was no direct contact with patients or health care providers for data collection. Basic demographics, injury details, event detail, injury severity and outcome were recorded. Data was entered in the KITR and reports were generated. Complete data of 542 patients were entered and analysed. The mean age of patients was 27 years, and 72.5% were males. About 87% of patients had sustained blunt injury. Falls and motor vehicle crashes were the most common mechanisms of injury. Head and face, followed by the extremities, were the most frequently injured anatomical regions. The mean Injury Severity Score (ISS) was 4.99 and there were 8 deaths. The most common missing variables in the medical records were ethnicity, ED notification prior to transfer, and pre-hospital IV fluids. Average time to review each chart was 14.5 minutes and entry into the electronic registry required 15 minutes. Using existing medical records, we were able to enter data on most variables including mechanism of injuries, burden of severe injuries and quality indicators such as length of stay in ED, injury to arrival delay, as well as generate injury severity and survival probability but missed information such as ethnicity, ED notification. To make the data collection process more effective, we propose provider based data collection or making a standardized data collection tool a part of medical records.

An ATM-independent S-phase checkpoint response involves CHK1 pathway

NASA Technical Reports Server (NTRS)

Zhou, Xiang-Yang; Wang, Xiang; Hu, Baocheng; Guan, Jun; Iliakis, George; Wang, Ya

2002-01-01

After exposure to genotoxic stress, proliferating cells actively slow down the DNA replication through a S-phase checkpoint to provide time for repair. We report that in addition to the ataxia-telangiectasia mutated (ATM)-dependent pathway that controls the fast response, there is an ATM-independent pathway that controls the slow response to regulate the S-phase checkpoint after ionizing radiation in mammalian cells. The slow response of S-phase checkpoint, which is resistant to wortmannin, sensitive to caffeine and UCN-01, and related to cyclin-dependent kinase phosphorylation, is much stronger in CHK1 overexpressed cells, and it could be abolished by Chk1 antisense oligonucleotides. These results provide evidence that the ATM-independent slow response of S-phase checkpoint involves CHK1 pathway.

Audit of sharp weapon deaths in metropolis of Karachi--an autopsy based study.

PubMed

Mirza, Farhat Hussain; Hasan, Qudsia; Memon, Akhtar Amin; Adil, Syeda Ezz-e-Rukhshan

2010-01-01

Sharp weapons are one of the most violent and abhorrent means of deaths. This study assesses the frequency of sharp weapon deaths in Karachi. This was a cross sectional study, and involves the deaths by sharp weapons autopsied in Karachi during Mar 2008-Feb 2009. This study reports that the frequency of sharp weapon deaths in Karachi is similar to some other studies conducted in different regions of Pakistan, yet it is very high as the population of Karachi is way more than any other metropolis of Pakistan. Our study reported that out of 2090 medico-legal deaths in Karachi during the study period, 91 deaths were due to sharp weapons, including 73 (80.2%) males and 18 (19.8%) females. 100% of the deaths were homicides, so none were suicides. Deaths were more frequent in age group ranging from 20-39 years (59.3%). Sharp weapon deaths continue to be a means of quite a number of deaths in Karachi. Such violence depicts intolerant and frustrated nature of the citizens.

Perspectives on the combination of radiotherapy and targeted therapy with DNA repair inhibitors in the treatment of pancreatic cancer

PubMed Central

Yang, Shih-Hung; Kuo, Ting-Chun; Wu, Hsu; Guo, Jhe-Cyuan; Hsu, Chiun; Hsu, Chih-Hung; Tien, Yu-Wen; Yeh, Kun-Huei; Cheng, Ann-Lii; Kuo, Sung-Hsin

2016-01-01

Pancreatic cancer is highly lethal. Current research that combines radiation with targeted therapy may dramatically improve prognosis. Cancerous cells are characterized by unstable genomes and activation of DNA repair pathways, which are indicated by increased phosphorylation of numerous factors, including H2AX, ATM, ATR, Chk1, Chk2, DNA-PKcs, Rad51, and Ku70/Ku80 heterodimers. Radiotherapy causes DNA damage. Cancer cells can be made more sensitive to the effects of radiation (radiosensitization) through inhibition of DNA repair pathways. The synergistic effects, of two or more combined non-lethal treatments, led to co-administration of chemotherapy and radiosensitization in BRCA-defective cells and patients, with promising results. ATM/Chk2 and ATR/Chk1 pathways are principal regulators of cell cycle arrest, following DNA double-strand or single-strand breaks. DNA double-stranded breaks activate DNA-dependent protein kinase, catalytic subunit (DNA-PKcs). It forms a holoenzyme with Ku70/Ku80 heterodimers, called DNA-PK, which catalyzes the joining of nonhomologous ends. This is the primary repair pathway utilized in human cells after exposure to ionizing radiation. Radiosensitization, induced by inhibitors of ATM, ATR, Chk1, Chk2, Wee1, PP2A, or DNA-PK, has been demonstrated in preclinical pancreatic cancer studies. Clinical trials are underway. Development of agents that inhibit DNA repair pathways to be clinically used in combination with radiotherapy is warranted for the treatment of pancreatic cancer. PMID:27621574

Cost effectiveness of screening of all newly recruited employees for diabetes at a tertiary care hospital.

PubMed

Ali, Niloufer Sultan; Khuwaja, Ali Khan

2007-01-01

Diabetes Mellitus is a disease which remains asymptomatic for long duration of time and usually diagnosed either when gets complicated or by routine or opportunistic screening. The practice of universal screening is not recommended, particularly in constraint resources. However, we embarked with a study to assess the yield of recommended screening for Type 2 diabetes in all the newly recruited employees at a tertiary care hospital in Karachi. All the information required for this study was collected from medical records of all newly recruited employees of nursing services department of a tertiary care hospital of Karachi, Pakistan, over a period of 5 months (August 2004 to December 2004). Out of 360 subjects, 326, whose information was found to be complete, were included for final analysis. Mean age of the study subjects was 25.3 +/- 4.7 years and their mean casual plasma glucose level was 99.1 +/- 16.3 mg/dl. 315 (96.6%) study subjects had casual plasma glucose level of 139 mg/dl or less. Only 10 (3.1%) study subjects had casual plasma glucose levels between 140 to 199 mg/dl. Just one employee, 41 years old, was found to have casual plasma glucose level of 213 mg/dl. In this study, screening of all individuals for diabetes had a very low yield. Recommendation of universal screening for diabetes does not represent a good use of resources and perhaps not cost-effective. However, periodic screening of high risk individuals should be warranted.

Chk2 and REGγ-dependent DBC1 regulation in DNA damage induced apoptosis

PubMed Central

Magni, Martina; Ruscica, Vincenzo; Buscemi, Giacomo; Kim, Ja-Eun; Nachimuthu, Benjamin Tamilselvan; Fontanella, Enrico; Delia, Domenico; Zannini, Laura

2014-01-01

Human DBC1 (Deleted in Breast Cancer 1; KIAA1967; CCAR2) is a protein implicated in the regulation of apoptosis, transcription and histone modifications. Upon DNA damage, DBC1 is phosphorylated by ATM/ATR on Thr454 and this modification increases its inhibitory interaction with SIRT1, leading to p53 acetylation and p53-dependent apoptosis. Here, we report that the inhibition of SIRT1 by DBC1 in the DNA damage response (DDR) also depends on Chk2, the transducer kinase that is activated by ATM upon DNA lesions and contributes to the spreading of DNA damage signal. Indeed we found that inactivation of Chk2 reduces DBC1-SIRT1 binding, thus preventing p53 acetylation and DBC1-induced apoptosis. These events are mediated by Chk2 phosphorylation of the 11S proteasome activator REGγ on Ser247, which increases REGγ-DBC1 interaction and SIRT1 inhibition. Overall our results clarify the mechanisms underlying the DBC1-dependent SIRT1 inhibition and link, for the first time, Chk2 and REGγ to the ATM-DBC1-SIRT1 axis. PMID:25361978

Pharmacological activation of a novel p53-dependent S-phase checkpoint involving CHK-1

PubMed Central

Ahmed, A; Yang, J; Maya-Mendoza, A; Jackson, D A; Ashcroft, M

2011-01-01

We have recently shown that induction of the p53 tumour suppressor protein by the small-molecule RITA (reactivation of p53 and induction of tumour cell apoptosis; 2,5-bis(5-hydroxymethyl-2-thienyl)furan) inhibits hypoxia-inducible factor-1α and vascular endothelial growth factor expression in vivo and induces p53-dependent tumour cell apoptosis in normoxia and hypoxia. Here, we demonstrate that RITA activates the canonical ataxia telangiectasia mutated/ataxia telangiectasia and Rad3-related DNA damage response pathway. Interestingly, phosphorylation of checkpoint kinase (CHK)-1 induced in response to RITA was influenced by p53 status. We found that induction of p53, phosphorylated CHK-1 and γH2AX proteins was significantly increased in S-phase. Furthermore, we found that RITA stalled replication fork elongation, prolonged S-phase progression and induced DNA damage in p53 positive cells. Although CHK-1 knockdown did not significantly affect p53-dependent DNA damage or apoptosis induced by RITA, it did block the ability for DNA integrity to be maintained during the immediate response to RITA. These data reveal the existence of a novel p53-dependent S-phase DNA maintenance checkpoint involving CHK-1. PMID:21593792

Pandemic influenza A(H1N1)pdm09: An unrecognized cause of mortality in children in Pakistan

PubMed Central

ALI, SYED ASAD; AZIZ, FATIMA; AKHTAR, NIDA; QURESHI, SHAHIDA; EDWARDS, KATHRYN; ZAIDI, ANITA

2016-01-01

The role of influenza virus as a cause of child mortality in South Asia is under-recognized. We aimed to determine the incidence and case fatality rate of influenza A(H1N1)pdm09 infections in hospitalized children in Karachi, Pakistan. Children less than 5 y old admitted with respiratory illnesses to the Aga Khan University Hospital, Karachi, from 17 August 2009 to 16 September 2011, were tested for influenza A(H1N1)pdm09 using a real-time reverse transcriptase polymerase chain reaction. Out of 2650 children less than 5 y old admitted with a respiratory illness during the study period, 812 (31%) were enrolled. Influenza A(H1N1)pdm09 virus was detected in 27 (3.3%) children. There were 4 deaths in children who tested positive for influenza A(H1N1)pdm09 (case fatality rate of 15%). Children with influenza A(H1N1)pdm09 were 5 times more likely to be admitted or transferred to the intensive care unit, 5.5 times more likely to be intubated, and 12.9 times more likely to die as compared to children testing negative for influenza A(H1N1)pdm09. PMID:23826795

Neonatal resuscitation: a knowledge gap amongst obstetrical trainees. A cross-sectional survey amongst medical graduates of Civil Hospital Karachi.

PubMed

Noor, Tooba; Raza, Natasha; Haq, Gulfishan

2014-07-01

To evaluate the neonatal resuscitation competence of obstetrical trainees to assess the gap in knowledge and to determine training needs. The cross-sectional study was conducted at the Department of Gynaecology and Obstetrics, Civil Hospital, Karachi, from January to March 2013 and comprised House Officers and Postgraduate trainees. A questionnaire was used to test the evaluation skills of different conditions and choice of appropriate action required during neonatal resuscitation. Data was collected and analysed through SPSS 17.0. Of the 102 obstetrical trainees, 44 (43.1%) were House Officers and 58 (56.9%) were Postgraduate trainees with an overall mean age 25.69 +/- 2.3 years. Only 19 (18.6%) subjects cleared the test; 8 (42.1%) of them were House Officers and 11 (57.9%) were Postgraduate trainees. The result did not show any significant difference between those who had previous training or those who had performed neonatal resuscitation and those who had no such exposure. Majority, 92 (90.2%) considered their knowledge inadequate and 99 (97%) favoured that updated neonatal resuscitation programmes should be periodically arranged. The study showed inadequate level of knowledge on neonatal resuscitation amongst obstetrical trainees. There is urgent need of formal training programmes which can make doctors skilful enough to face any adverse neonatal outcome professionally.

Csk Homologous Kinase, a Potential Regulator of CXCR4-Medicated Breast Cancer Cell Metastasis

DTIC Science & Technology

2011-08-01

is a non-receptor tyrosine kinase and a second member of the Csk family. Like Csk, CHK has Src homology 2 ( SH2 ) and SH3 domains and lacks the...MSCV-retroviral vectors encoding either wild-type CHK or kinase -dead CHK or wild type SH2 domain or SH2 -R147A or SH2 -G129A. All these constructs were... Kinase , a Potential Regulator of CXCR4-Medicated Breast Cancer Cell Metastasis Byeong-Chel Lee The University of Pittsburgh Pittsburgh, PA 15213

DNA damage checkpoint pathway modulates the regulation of skeletal growth and osteoblastic bone formation by parathyroid hormone-related peptide.

PubMed

Zhang, Ying; Chen, Guangpei; Gu, Zhen; Sun, Haijian; Karaplis, Andrew; Goltzman, David; Miao, Dengshun

2018-01-01

We previously demonstrated that parathyroid hormone-related peptide (PTHrP) 1-84 knockin ( Pthrp KI) mice, which lacked a PTHrP nuclear localization sequence (NLS) and C-terminus, displayed early senescence, defective osteoblastic bone formation, and skeletal growth retardation. However, the mechanism of action of the PTHrP NLS and C-terminus in regulating development of skeleton is still unclear. In this study, we examined alterations of oxidative stress and DNA damage response-related molecules in Pthrp KI skeletal tissue. We found that ROS levels, protein expression levels of γ-H2AX, a DNA damage marker, and the DNA damage response markers p-Chk2 and p53 were up-regulated, whereas gene expression levels of anti-oxidative enzymes were down-regulated significantly. We therefore further disrupted the DNA damage response pathway by deleting the Chk2 in Pthrp KI (Chk2 -/- KI) mice and did comparison with WT, Chk2 -/- and Pthrp KI littermates. The Pthrp KI mice with Chk2 deletion exhibited a longer lifespan, improvement in osteoblastic bone formation and skeletal growth including width of growth plates and length of long bones, trabecular and epiphyseal bone volume, BMD, osteoblast numbers, type I collagen and ALP positive bone areas, the numbers of total colony-forming unit fibroblasts (CFU-f), ALP + CFU-f and the expression levels of osteogenic genes. In addition, the genes associated with anti-oxidative enzymes were up-regulated significantly, whereas the tumor suppressor genes related to senescence were down-regulated in Chk2 -/- KI mice compared to Pthrp KI mice. Our results suggest that Chk2 deletion in Pthrp KI mice can somewhat rescue defects in osteoblastic bone formation and skeletal growth by enhancing endochondral bone formation and osteogenesis. These studies therefore indicate that the DNA damage checkpoint pathway may be a target for the nuclear action of PTHrP to regulate skeletal development and growth.

Mangiferin induces cell cycle arrest at G2/M phase through ATR-Chk1 pathway in HL-60 leukemia cells.

PubMed

Peng, Z G; Yao, Y B; Yang, J; Tang, Y L; Huang, X

2015-05-12

This study aimed to determine the effect of mangiferin on the cell cycle in HL-60 leukemia cells and expression of the cell cycle-regulatory genes Wee1, Chk1 and CDC25C and to further investigate the molecular mechanisms of the antileukemic action of mangiferin. The inhibitory effect of mangiferin on HL-60 leukemia cell proliferation was determined by the MTT assay. The impact of mangiferin on the HL-60 cell cycle was evaluated by flow cytometry. After the cells were treated with different concentrations of mangiferin, the expression levels of Wee1, Chk1 and CDC25C mRNA were determined by RT-PCR, and Western blot was used to evaluate the expression levels of cdc25c, cyclin B1, and Akt proteins. The inhibition of HL-60 cell growth by mangiferin was dose- and time-dependent. After treatment for 24 h, cells in G2/M phase increased, and G2/M phase arrest appeared with increased mRNA expression of Wee1, Chk1 and CDC25C. Mangiferin inhibited Chk1 and cdc25c mRNA expression at high concentrations and induced Wee1 mRNA expression in a dose-dependent manner. It significantly inhibited ATR, Chk1, Wee1, Akt, and ERK1/2 phosphorylation but increased cdc2 and cyclin B1 phosphorylation. Furthermore, mangiferin reduced cdc25c, cyclin B1, and Akt protein levels while inducing Wee1 protein expression. It also antagonized the phosphorylation effect of vanadate on ATR, and the phosphorylation effect of EGF on Wee1. These findings indicated that mangiferin inhibits cell cycle progression through the ATR-Chk1 stress response DNA damage pathway, leading to cell cycle arrest at G2/M phase in leukemia cells.

Risk factors predicting mortality in patients with lung abscess in a public tertiary care center in Karachi, Pakistan.

PubMed

Ghazal, Shaista; Kumar, Ashok; Shrestha, Binav; Sajid, Sana; Malik, Maria; Rizvi, Nadeen

2013-01-01

Lung abscess is a commonly encountered entity in South-East Asia but not much data regarding its outcome is available. The objective of this study was to identify the factors associated with increased mortality in patients diagnosed with lung abscess in a tertiary care center of Karachi, Pakistan. A retrospective case analysis was performed via hospital records, on patients admitted with lung abscess between January 2009 and January 2011 at the largest state-owned tertiary care centre in Karachi, Pakistan. Out of the 41 patients hospitalized, 17 could not survive and were evaluated for clinical, radiological and microbiological factors to determine association with heightened mortality. Mortality due to lung abscess stood at 41.4% (17 of 41 cases). Adult male patients were found to have higher mortality with 13 out of 17 (43%) dead patients being male. A majority (21/41, 51.2%) of the cases belonged to the 41-60 year old age group. Highest mortality was seen in patients<20 years of age (3/4, 75%). Patients with blood sugar levels of >200 mg/dL (56%) succumb to disease. Patients with a positive history of smoking, diabetes mellitus, and alcohol intake expressed mortality rates of 44%, 56%, and 50% respectively; while 29.4% of the mortalities were positive for Pseudomonas aeruginosa on sputum culture. A significant association was found with elevated mortality and low haemoglobin levels at time of admission; mortality was 58% (p=0.005) in patients with Hb less than or equal to 10 mg/dL. The risk factors involved with heightened mortality included male gender and history of smoking, diabetes and alcohol intake. High blood sugar levels and detection of Pseudomonas aeruginosa on sputum cultures were also implicated. Anemia (Hb level less than or equal to 10 mg/dl) was statistically significant predictive factor for increased mortality.

HEALTH CARE PERSONNEL AND WORKPLACE VIOLENCE IN THE EMERGENCY DEPARTMENTS OF A VOLATILE METROPOLIS: RESULTS FROM KARACHI, PAKISTAN

PubMed Central

Zafar, Waleed; Siddiqui, Emaduddin; Ejaz, Kiran; Shehzad, Muhammad Umer; Khan, Uzma Rahim; Jamali, Seemin; Razzak, Junaid A.

2015-01-01

Background Workplace violence (WPV) is an important challenge faced by health care personnel in the emergency department (ED). Study Objectives To determine the prevalence and nature of WPV reported by physicians and nurses working in the EDs of four of the largest tertiary care hospitals in Karachi, Pakistan and to understand the mental health impact of experiencing WPV. Methods This cross-sectional survey was conducted between September and November 2008 using a widely used questionnaire developed by the World Health Organization. Overall, 266 (86% response rate) questionnaires were included in this study. Results A total of 44 (16.5%) physicians and nurses said they had been physically attacked, and 193 (72.5%) said that they had experienced verbal abuse in the last 12 months. Among those who reported physical attack, 29.6% reported that the last incident involved a weapon, and in 64% of cases the attacker was a patient’s relative. Eighty-six percent thought that the last attack could have been prevented, and 64% said that no action was taken against the attacker. After adjusting for covariates, physicians were less likely than nurses to report physical attack (odds ratio [OR] 0.46; 95% confidence interval [CI] 0.2–1.0), and personnel with greater work experience (OR 4.8; 95% CI 2.0–11.7) and those who said that there were procedures to report WPV in their workplace (OR 3.2; 95% CI 1.6–6.5) were more likely to report verbal abuse. WPV was associated with mental health effects in the form of bothersome memories, super-alertness, and feelings of avoidance and futility. Conclusion WPV is an important challenge in the EDs of large hospitals in Karachi. A majority of respondents feel that WPV is preventable, but only a minority of attackers face consequences. PMID:24011477

Molecular and epidemiological characterisation of clinical isolates of carbapenem-resistant Acinetobacter baumannii from public and private sector intensive care units in Karachi, Pakistan.

PubMed

Irfan, S; Turton, J F; Mehraj, J; Siddiqui, S Z; Haider, S; Zafar, A; Memon, B; Afzal, O; Hasan, R

2011-06-01

The purpose of this study was to identify molecular and epidemiological characteristics of hospital-acquired carbapenem-resistant Acinetobacter baumannii (CRAB) from two different intensive care unit (ICU) settings in Karachi, Pakistan. A cross-sectional study was performed in the adult ICUs of a private sector tertiary care hospital (PS-ICU) and of a government sector hospital (GS-ICU) between November 2007 and August 2008. Deduplicated CRAB isolates from clinical specimens were examined for carbapenemase and class 1 integrase genes. Isolates were typed using sequence-based multiplex polymerase chain reaction, pulsed-field gel electrophoresis (PFGE) and variable number tandem repeat (VNTR). A total of 50 patients (33 from PS-ICU and 17 from GS-ICU) were recruited. There were statistically significant differences between patients in the two ICUs in terms of mean age, comorbidities, the presence of central venous pressure lines, urinary catheters, and average length of stay. bla(OxA-23-like) acquired-oxacillinase genes were found in 47/50 isolates. Class 1 integrase genes were found in 50% (25/50) of the organisms. The majority of isolates belonged to strains of European clones I and II. PFGE typing grouped the isolates into eight distinct clusters, three of which were found in both hospitals. Most of the isolates within each PFGE cluster shared identical or highly similar VNTR profiles, suggesting close epidemiological association. Irrespective of differences in risk factors and infection control policies and practices, the extent of clonality among CRAB isolates was very similar in both ICU settings. Copyright © 2011 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

Routine Sub-hepatic Drainage versus No Drainage after Laparoscopic Cholecystectomy: Open, Randomized, Clinical Trial.

PubMed

Shamim, Muhammad

2013-02-01

Surgeons are still following the old habit of routine subhepatic drainage following laparoscopic cholecystectomy (LC). This study aims to compare the outcome of subhepatic drainage with no drainage after LC. This prospective study was conducted in two phases. Phase I was open, randomized controlled trial (RCT), conducted in Civil Hospital Karachi, from August 2004 to June 2005. Phase II was descriptive case series, conducted in author's practice hospitals of Karachi, from July 2005 to December 2009. In phase I, 170 patients with chronic calculous cholecystitis underwent LC. Patients were divided into two groups, subhepatic drainage (group A: 79 patients) or no drainage (group B: 76 patients). The rest 15 patients were excluded either due to conversion or elective subhepatic drainage. In phase II, 218 consecutive patients were enrolled, who underwent LC with no subhepatic drainage. Duration of operation, character, and amount of drain fluid (if placed), postoperative ultrasound for subhepatic collection, postoperative chest X-ray for the measurement of subdiaphragmatic air, postoperative pain, postoperative nausea/vomiting, duration of hospital stay, and preoperative or postoperative complications were noted and analyzed. Duration of operation and hospital stay was slightly longer in group A patients (P values 0.002 and 0.029, respectively); postoperative pain perception, nausea/vomiting, and postoperative complications were nearly same in both groups (P value 0.064, 0.078, and 0.003, respectively). Subhepatic fluid collection was more in group A (P = 0.002), whereas subdiaphragmatic air collection was more in group B (P = 0.003). Phase II results were nearly similar to group B patients in phase I. Routine subhepatic drainage after LC is not necessary in uncomplicated cases.

Effects of Selective Checkpoint Kinase 1 Inhibition on Cytarabine Cytotoxicity in Acute Myelogenous Leukemia Cells in Vitro

PubMed Central

Schenk, Erin L.; Koh, Brian D.; Flatten, Karen S.; Peterson, Kevin L.; Parry, David; Hess, Allan D.; Smith, B. Douglas; Karp, Judith E.; Karnitz, Larry M.; Kaufmann, Scott H.

2012-01-01

Purpose Previous studies have demonstrated that the replication checkpoint, which involves the kinases ATR and Chk1, contributes to cytarabine resistance in cell lines. In the present study, we examined whether this checkpoint is activated in clinical AML during cytarabine infusion in vivo and then assessed the impact of combining cytarabine with the recently described Chk1 inhibitor SCH 900776 in vitro. Experimental design AML marrow aspirates harvested before and during cytarabine infusion were examined by immunoblotting. Human AML lines treated with cytarabine in the absence or presence of SCH 900776 were assayed for checkpoint activation by immunoblotting, nucleotide incorporation into DNA and flow cytometry. Long-term effects in AML lines, clinical AML isolates, and normal myeloid progenitors were assayed using clonogenic assays. Results Immunoblotting demonstrated increased Chk1 phosphorylation, a marker of checkpoint activation, in over half of Chk1-containing AMLs after 48 h of cytarabine infusion. In human AML lines, SCH 900776 not only disrupted cytarabine-induced Chk1 activation and S phase arrest, but also markedly increased cytarabine-induced apoptosis. Clonogenic assays demonstrated that SCH 900776 enhanced the anti-proliferative effects of cytarabine in AML cell lines and clinical AML samples at concentrations that had negligible impact on normal myeloid progenitors. Conclusions These results not only provide evidence for cytarabine-induced S phase checkpoint activation in AML in the clinical setting, but also show that a selective Chk1 inhibitor can overcome the S phase checkpoint and enhance the cytotoxicity of cytarabine. Accordingly, further investigation of the cytarabine/SCH 900776 combination in AML appears warranted. PMID:22869869

Claspin Promotes Normal Replication Fork Rates in Human Cells

PubMed Central

Helleday, Thomas; Caldecott, Keith W.

2008-01-01

The S phase-specific adaptor protein Claspin mediates the checkpoint response to replication stress by facilitating phosphorylation of Chk1 by ataxia-telangiectasia and Rad3-related (ATR). Evidence suggests that these components of the ATR pathway also play a critical role during physiological S phase. Chk1 is required for high rates of global replication fork progression, and Claspin interacts with the replication machinery and might therefore monitor normal DNA replication. Here, we have used DNA fiber labeling to investigate, for the first time, whether human Claspin is required for high rates of replication fork progression during normal S phase. We report that Claspin-depleted HeLa and HCT116 cells display levels of replication fork slowing similar to those observed in Chk1-depleted cells. This was also true in primary human 1BR3 fibroblasts, albeit to a lesser extent, suggesting that Claspin is a universal requirement for high replication fork rates in human cells. Interestingly, Claspin-depleted cells retained significant levels of Chk1 phosphorylation at both Ser317 and Ser345, raising the possibility that Claspin function during normal fork progression may extend beyond facilitating phosphorylation of either individual residue. Consistent with this possibility, depletion of Chk1 and Claspin together doubled the percentage of very slow forks, compared with depletion of either protein alone. PMID:18353973

Panobinostat Enhances Cytarabine and Daunorubicin Sensitivities in AML Cells through Suppressing the Expression of BRCA1, CHK1, and Rad51

PubMed Central

Edwards, Holly; Caldwell, J. Timothy; Chen, Wei; Inaba, Hiroto; Xu, Xuelian; Buck, Steven A.; Taub, Jeffrey W.; Baker, Sharyn D.; Ge, Yubin

2013-01-01

Acute myeloid leukemia (AML) remains a challenging disease to treat and urgently requires new therapies to improve its treatment outcome. In this study, we investigated the molecular mechanisms underlying the cooperative antileukemic activities of panobinostat and cytarabine or daunorubicin (DNR) in AML cell lines and diagnostic blast samples in vitro and in vivo. Panobinostat suppressed expression of BRCA1, CHK1, and RAD51 in AML cells in a dose-dependent manner. Further, panobinostat significantly increased cytarabine- or DNR-induced DNA double-strand breaks and apoptosis, and abrogated S and/or G2/M cell cycle checkpoints. Analogous results were obtained by shRNA knockdown of BRCA1, CHK1, or RAD51. Cotreatment of NOD-SCID-IL2Rγnull mice bearing AML xenografts with panobinostat and cytarabine significantly increased survival compared to either cytarabine or panobinostat treatment alone. Additional studies revealed that panobinostat suppressed the expression of BRCA1, CHK1, and RAD51 through downregulation of E2F1 transcription factor. Our results establish a novel mechanism underlying the cooperative antileukemic activities of these drug combinations in which panobinostat suppresses expression of BRCA1, CHK1, and RAD51 to enhance cytarabine and daunorubicin sensitivities in AML cells. PMID:24244429

Clinical types of tinea capitis and species identification in children: an experience from tertiary care centres of Karachi, Pakistan.

PubMed

Farooqi, Maria; Tabassum, Saadia; Rizvi, Dilawar Abbas; Rahman, Atiya; Rehanuddin; Awan, Safia; Mahar, Sikandar Azam

2014-03-01

To study the clinical types of Tinea Capitis and identify species in children reporting to two tertiary care centres of Karachi, Pakistan. The descriptive, cross-sectional study was conducted at the Dermatology Outpatients' Department, PNS Shifa Hospital and the Institute of Skin Diseases, Karachi, from January 1, 2008 to December 31, 2009. It comprised 202 children with clinical diagnosis of tinea capitis, confirmed by skin scrapings, showing fungal hyphae and spores in 10% potassium hydroxide on direct microscopy. Wood's lamp examination was carried out and the scrapings were cultured on Sabouraud's agar. A detailed dermatological examination was performed for evidence of fungal infection elsewhere in the body. SPSS 19 was used for data analysis. Male-to-female ratio was 1.1:1 and age ranged from 1 to 14 years.The commonest clinical type gray patch was observed in 71 (35.1%) of the patients, black dot in 63 (31.2%), kerion in 50 (24.8%), favus in 10 (5.0%), diffuse pustular in 6 (3.0%), and diffuse scale in 2 (1.0%) patients. The most frequent species grown on culture was Trichophyton (T). Soudanense, followed by T. Tonsurans, T. Schoenleinii, and T. Mentagrophytes respectively. Most of the patients of Tinea capitis presented with gray patch and black dot variety. The most common species identified by culture was Trichophyton Soudanense. Disease was equal in both gender and predominantly affected the population belonging to low and middle socioeconomic class.

Water extract of gromwell (Lithospermum erythrorhizon) enhances migration of human keratinocytes and dermal fibroblasts with increased lipid synthesis in an in vitro wound scratch model.

PubMed

Kim, H; Kim, J; Park, J; Kim, S H; Uchida, Y; Holleran, W M; Cho, Y

2012-01-01

Although organic extracts of gromwell (Lithospermum erythrorhizon) have been shown to promote wound healing, the wound healing effects of water extracts of gromwell (WG) that are commonly used in traditional remedies have not been elucidated. We investigated whether WG promotes the migration and/or proliferation of cultured human keratinocytes (CHK) or dermal fibroblasts in parallel with increases in lipid synthesis during in vitro wound healing. CHK or fibroblasts were treated with 1-1,000 μg/ml WG for up to 48 h following scratch wound formation. Cell migration was assessed by measuring coverage (in percent) from the wound margin, while cell proliferation and lipid synthesis were determined by [(3)H]thymidine incorporation into DNA fractions, and [(3)H]palmitate or [(3)H]serine incorporation into lipid fractions, respectively. Low-dose WG (1 μg/ml) enhanced the wound coverage for both CHK and fibroblasts at 24 h, while cell proliferation was not altered in either cell types. Synthesis of both total lipids and individual lipid classes, including phospholipids, sphingolipids and neutral lipids, were found to be increased at 24 h in CHK treated with 1 μg/ml WG; in similarly treated fibroblasts, only the syntheses of sphingolipids (such as ceramides and glucosylceramides), but not other lipid species, were significantly increased. In contrast, a higher dose of WG (10-1,000 μg/ml) did not enhance wound coverage, and 100 μg/ml WG neither altered cell proliferation nor lipid synthesis in both CHK and fibroblasts. Low-dose WG (1 μg/ml) enhances the migration of both CHK and fibroblasts with increased lipid synthesis in an in vitro wound scratch model. Copyright © 2011 S. Karger AG, Basel.

The Checkpoint Kinase 1 Inhibitor Prexasertib Induces Regression of Preclinical Models of Human Neuroblastoma.

PubMed

Lowery, Caitlin D; VanWye, Alle B; Dowless, Michele; Blosser, Wayne; Falcon, Beverly L; Stewart, Julie; Stephens, Jennifer; Beckmann, Richard P; Bence Lin, Aimee; Stancato, Louis F

2017-08-01

Purpose: Checkpoint kinase 1 (CHK1) is a key regulator of the DNA damage response and a mediator of replication stress through modulation of replication fork licensing and activation of S and G 2 -M cell-cycle checkpoints. We evaluated prexasertib (LY2606368), a small-molecule CHK1 inhibitor currently in clinical testing, in multiple preclinical models of pediatric cancer. Following an initial assessment of prexasertib activity, this study focused on the preclinical models of neuroblastoma. Experimental Design: We evaluated the antiproliferative activity of prexasertib in a panel of cancer cell lines; neuroblastoma cell lines were among the most sensitive. Subsequent Western blot and immunofluorescence analyses measured DNA damage and DNA repair protein activation. Prexasertib was investigated in several cell line-derived xenograft mouse models of neuroblastoma. Results: Within 24 hours, single-agent prexasertib promoted γH2AX-positive double-strand DNA breaks and phosphorylation of DNA damage sensors ATM and DNA-PKcs, leading to neuroblastoma cell death. Knockdown of CHK1 and/or CHK2 by siRNA verified that the double-strand DNA breaks and cell death elicited by prexasertib were due to specific CHK1 inhibition. Neuroblastoma xenografts rapidly regressed following prexasertib administration, independent of starting tumor volume. Decreased Ki67 and increased immunostaining of endothelial and pericyte markers were observed in xenografts after only 6 days of exposure to prexasertib, potentially indicating a swift reduction in tumor volume and/or a direct effect on tumor vasculature. Conclusions: Overall, these data demonstrate that prexasertib is a specific inhibitor of CHK1 in neuroblastoma and leads to DNA damage and cell death in preclinical models of this devastating pediatric malignancy. Clin Cancer Res; 23(15); 4354-63. ©2017 AACR . ©2017 American Association for Cancer Research.

Human T-cell leukemia virus-I tax oncoprotein functionally targets a subnuclear complex involved in cellular DNA damage-response.

PubMed

Haoudi, Abdelali; Daniels, Rodney C; Wong, Eric; Kupfer, Gary; Semmes, O John

2003-09-26

The virally encoded oncoprotein Tax has been implicated in HTLV-1-mediated cellular transformation. The exact mechanism by which this protein contributes to the oncogenic process is not known. However, it has been hypothesized that Tax induces genomic instability via repression of cellular DNA repair. We examined the effect of de novo Tax expression upon the cell cycle, because appropriate activation of cell cycle checkpoints is essential to a robust damage-repair response. Upon induction of tax expression, Jurkat T-cells displayed a pronounced accumulation in G2/M that was reversible by caffeine. We examined the G2-specific checkpoint signaling response in these cells and found activation of the ATM/chk2-mediated pathway, whereas the ATR/chk1-mediated response was unaffected. Immunoprecipitation with anti-chk2 antibody results in co-precipitation of Tax demonstrating a direct interaction of Tax with a chk2-containing complex. We also show that Tax targets a discrete nuclear site and co-localizes with chk2 and not chk1. This nuclear site, previously identified as Tax Speckled Structures (TSS), also contains the early damage response factor 53BP1. The recruitment of 53BP1 to TSS is dependent upon ATM signaling and requires expression of Tax. Specifically, Tax expression induces redistribution of diffuse nuclear 53BP1 to the TSS foci. Taken together these data suggest that the TSS describe a unique nuclear site involved in DNA damage recognition, repair response, and cell cycle checkpoint activation. We suggest that association of Tax with this multifunctional subnuclear site results in disruption of a subset of the site-specific activities and contributes to cellular genomic instability.

Chk1/2 inhibition overcomes the cisplatin resistance of head and neck cancer cells secondary to the loss of functional p53

PubMed Central

Gadhikar, Mayur A.; Sciuto, Maria Rita; Alves, Marcus Vinicius Ortega; Pickering, Curtis R.; Osman, Abdullah A.; Neskey, David M.; Zhao, Mei; Fitzgerald, Alison L.; Myers, Jeffrey N.; Frederick, Mitchell J

2014-01-01

Despite the use of multimodality therapy employing cisplatin to treat patients with advanced stage head and neck squamous cell carcinoma (HNSCC), there is an unacceptably high rate of treatment failure. TP53 is the most commonly mutated gene in HNSCC, and the impact of p53 mutation on response to cisplatin treatment is poorly understood. Here we show unambiguously that wild type TP53 (wtp53) is associated with sensitivity of HNSCC cells to cisplatin treatment while mutation or loss of TP53 is associated with cisplatin resistance. We also demonstrate that senescence is the major cellular response to cisplatin in wtp53 HNSCC cells and that cisplatin resistance in p53 null or mutant TP53 cells is due to their lack of senescence. Given the dependence on Chk1/2 kinases to mediate the DNA damage response in p53 deficient cells, there is potential to exploit this to therapeutic advantage through targeted inhibition of the Chk1/2 kinases. Treatment of p53 deficient HNSCC cells with the Chk inhibitor AZD7762 sensitizes them to cisplatin through induction of mitotic cell death. This is the first report demonstrating the ability of a Chk kinase inhibitor to sensitize TP53-deficient HNSCC to cisplatin in a synthetic lethal manner, which has significance given the frequency of TP53 mutations in this disease and because cisplatin has become part of standard therapy for aggressive HNSCC tumors. These pre-clinical data provide evidence that a personalized approach to the treatment of HNSCC based on Chk inhibition in p53 mutant tumors may be feasible. PMID:23839309

Caffeine decreases phospho-Chk1 (Ser317) and increases mitotic cells with cyclin B1 and caspase 3 in tumors from UVB-treated mice.

PubMed

Lu, Yao-Ping; Lou, You-Rong; Peng, Qing-Yun; Nghiem, Paul; Conney, Allan H

2011-07-01

Oral administration of caffeine to mice inhibits UVB-induced carcinogenesis, and these results are paralleled by epidemiology studies indicating that caffeinated coffee and tea intake (but not decaffeinated beverage intake) is associated with decreased incidence of nonmelanoma skin cancer. Topical applications of caffeine to the skin of SKH-1 mice that had previously been treated with UVB inhibited subsequent skin tumor development and stimulated apoptosis in tumors but not in nontumor areas of the epidermis. This study sought to determine the basis of these differential effects on tumor versus nontumor sites that can be induced by caffeine, long after all UVB treatment has ceased. The activation status of the ATR/Chk1 pathway in UVB-induced tumors and uninvolved skin was determined by quantitating phospho-Chk1 (Ser317) and induction of lethal mitosis in vivo in the presence and absence of topical caffeine treatment. In the absence of caffeine, we found that UVB-induced tumors often had islands of phospho-Chk1 (Ser317) staining cells that were not present in nontumor areas of the epidermis. Treatment of mice with topical caffeine significantly diminished phospho-Chk1 (Ser317) staining and increased the number of mitotic cells that expressed cyclin B1 and caspase 3 in tumors, consistent with caffeine-induced lethal mitosis selectively in tumors. We hypothesize that compared with adjacent uninvolved skin, UVB-induced skin tumors have elevated activation of, and dependence on, the ATR/Chk1 pathway long after UVB exposure has ceased and that caffeine can induce apoptosis selectively in tumors by inhibiting this pathway and promoting lethal mitosis.

Jaridonin-induced G2/M phase arrest in human esophageal cancer cells is caused by reactive oxygen species-dependent Cdc2-tyr15 phosphorylation via ATM–Chk1/2–Cdc25C pathway

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ma, Yong-Cheng; Su, Nan; Shi, Xiao-Jing

2015-01-15

Jaridonin, a novel diterpenoid from Isodon rubescens, has been shown previously to inhibit proliferation of esophageal squamous cancer cells (ESCC) through G2/M phase cell cycle arrest. However, the involved mechanism is not fully understood. In this study, we found that the cell cycle arrest by Jaridonin was associated with the increased expression of phosphorylation of ATM at Ser1981 and Cdc2 at Tyr15. Jaridonin also resulted in enhanced phosphorylation of Cdc25C via the activation of checkpoint kinases Chk1 and Chk2, as well as in increased phospho-H2A.X (Ser139), which is known to be phosphorylated by ATM in response to DNA damage. Furthermore,more » Jaridonin-mediated alterations in cell cycle arrest were significantly attenuated in the presence of NAC, implicating the involvement of ROS in Jaridonin's effects. On the other hand, addition of ATM inhibitors reversed Jaridonin-related activation of ATM and Chk1/2 as well as phosphorylation of Cdc25C, Cdc2 and H2A.X and G2/M phase arrest. In conclusion, these findings identified that Jaridonin-induced cell cycle arrest in human esophageal cancer cells is associated with ROS-mediated activation of ATM–Chk1/2–Cdc25C pathway. - Highlights: • Jaridonin induced G2/M phase arrest through induction of redox imbalance. • Jaridonin increased the level of ROS through depleting glutathione in cell. • ATM–Chk1/2–Cdc25C were involved in Jaridonin-induced cell cycle arrest. • Jaridonin selectively inhibited cancer cell viability and cell cycle progression.« less

Extremely Low-Frequency Electromagnetic Fields Cause G1 Phase Arrest through the Activation of the ATM-Chk2-p21 Pathway

PubMed Central

Huang, Chao-Ying; Chang, Cheng-Wei; Chen, Chaang-Ray; Chuang, Chun-Yu; Chiang, Chi-Shiun; Shu, Wun-Yi; Fan, Tai-Ching; Hsu, Ian C.

2014-01-01

In daily life, humans are exposed to the extremely low-frequency electromagnetic fields (ELF-EMFs) generated by electric appliances, and public concern is increasing regarding the biological effects of such exposure. Numerous studies have yielded inconsistent results regarding the biological effects of ELF-EMF exposure. Here we show that ELF-EMFs activate the ATM-Chk2-p21 pathway in HaCaT cells, inhibiting cell proliferation. To present well-founded results, we comprehensively evaluated the biological effects of ELF-EMFs at the transcriptional, protein, and cellular levels. Human HaCaT cells from an immortalized epidermal keratinocyte cell line were exposed to a 1.5 mT, 60 Hz ELF-EMF for 144 h. The ELF-EMF could cause G1 arrest and decrease colony formation. Protein expression experiments revealed that ELF-EMFs induced the activation of the ATM/Chk2 signaling cascades. In addition, the p21 protein, a regulator of cell cycle progression at G1 and G2/M, exhibited a higher level of expression in exposed HaCaT cells compared with the expression of sham-exposed cells. The ELF-EMF-induced G1 arrest was diminished when the CHK2 gene expression (which encodes checkpoint kinase 2; Chk2) was suppressed by specific small interfering RNA (siRNA). These findings indicate that ELF-EMFs activate the ATM-Chk2-p21 pathway in HaCaT cells, resulting in cell cycle arrest at the G1 phase. Based on the precise control of the ELF-EMF exposure and rigorous sham-exposure experiments, all transcriptional, protein, and cellular level experiments consistently supported the conclusion. This is the first study to confirm that a specific pathway is triggered by ELF-EMF exposure. PMID:25111195

Dnmt1-dependent Chk1 pathway suppression is protective against neuron division.

PubMed

Oshikawa, Mio; Okada, Kei; Tabata, Hidenori; Nagata, Koh-Ichi; Ajioka, Itsuki

2017-09-15

Neuronal differentiation and cell-cycle exit are tightly coordinated, even in pathological situations. When pathological neurons re-enter the cell cycle and progress through the S phase, they undergo cell death instead of division. However, the mechanisms underlying mitotic resistance are mostly unknown. Here, we have found that acute inactivation of retinoblastoma (Rb) family proteins (Rb, p107 and p130) in mouse postmitotic neurons leads to cell death after S-phase progression. Checkpoint kinase 1 (Chk1) pathway activation during the S phase prevented the cell death, and allowed the division of cortical neurons that had undergone acute Rb family inactivation, oxygen-glucose deprivation (OGD) or in vivo hypoxia-ischemia. During neurogenesis, cortical neurons became protected from S-phase Chk1 pathway activation by the DNA methyltransferase Dnmt1, and underwent cell death after S-phase progression. Our results indicate that Chk1 pathway activation overrides mitotic safeguards and uncouples neuronal differentiation from mitotic resistance. © 2017. Published by The Company of Biologists Ltd.

An overactivated ATR/CHK1 pathway is responsible for the prolonged G2 accumulation in irradiated AT cells

NASA Technical Reports Server (NTRS)

Wang, Xiang; Khadpe, Jay; Hu, Baocheng; Iliakis, George; Wang, Ya

2003-01-01

Induction of checkpoint responses in G1, S, and G2 phases of the cell cycle after exposure of cells to ionizing radiation (IR) is essential for maintaining genomic integrity. Ataxia telangiectasia mutated (ATM) plays a key role in initiating this response in all three phases of the cell cycle. However, cells lacking functional ATM exhibit a prolonged G2 arrest after IR, suggesting regulation by an ATM-independent checkpoint response. The mechanism for this ataxia telangiectasia (AT)-independent G2-checkpoint response remains unknown. We report here that the G2 checkpoint in irradiated human AT cells derives from an overactivation of the ATR/CHK1 pathway. Chk1 small interfering RNA abolishes the IR-induced prolonged G2 checkpoint and radiosensitizes AT cells to killing. These results link the activation of ATR/CHK1 with the prolonged G2 arrest in AT cells and show that activation of this G2 checkpoint contributes to the survival of AT cells.

γH2AX foci formation in the absence of DNA damage: mitotic H2AX phosphorylation is mediated by the DNA-PKcs/CHK2 pathway.

PubMed

Tu, Wen-Zhi; Li, Bing; Huang, Bo; Wang, Yu; Liu, Xiao-Dan; Guan, Hua; Zhang, Shi-Meng; Tang, Yan; Rang, Wei-Qing; Zhou, Ping-Kun

2013-11-01

Phosphorylated H2AX is considered to be a biomarker for DNA double-strand breaks (DSB), but recent evidence suggests that γH2AX does not always indicate the presence of DSB. Here we demonstrate the bimodal dynamic of H2AX phosphorylation induced by ionizing radiation, with the second peak appearing when G2/M arrest is induced. An increased level of γH2AX occurred in mitotic cells, and this increase was attenuated by DNA-PKcs inactivation or Chk2 depletion, but not by ATM inhibition. The phosphorylation-mimic CHK2-T68D abrogated the attenuation of mitotic γH2AX induced by DNA-PKcs inactivation. Thus, the DNA-PKcs/CHK2 pathway mediates the mitotic phosphorylation of H2AX in the absence of DNA damage. Copyright © 2013 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

Activation of DNA Damage Repair Pathways by Murine Polyomavirus

PubMed Central

Heiser, Katie; Nicholas, Catherine; Garcea, Robert L.

2016-01-01

Nuclear replication of DNA viruses activates DNA damage repair (DDR) pathways, which are thought to detect and inhibit viral replication. However, many DNA viruses also depend on these pathways in order to optimally replicate their genomes. We investigated the relationship between murine polyomavirus (MuPyV) and components of DDR signaling pathways including CHK1, CHK2, H2AX, ATR, and DNAPK. We found that recruitment and retention of DDR proteins at viral replication centers was independent of H2AX, as well as the viral small and middle T-antigens. Additionally, infectious virus production required ATR kinase activity, but was independent of CHK1, CHK2, or DNAPK signaling. ATR inhibition did not reduce the total amount of viral DNA accumulated, but affected the amount of virus produced, indicating a defect in virus assembly. These results suggest that MuPyV may utilize a subset of DDR proteins or non-canonical DDR signaling pathways in order to efficiently replicate and assemble. PMID:27529739

Zinc-finger protein-targeted gene regulation: Genomewide single-gene specificity

PubMed Central

Tan, Siyuan; Guschin, Dmitry; Davalos, Albert; Lee, Ya-Li; Snowden, Andrew W.; Jouvenot, Yann; Zhang, H. Steven; Howes, Katherine; McNamara, Andrew R.; Lai, Albert; Ullman, Chris; Reynolds, Lindsey; Moore, Michael; Isalan, Mark; Berg, Lutz-Peter; Campos, Bradley; Qi, Hong; Spratt, S. Kaye; Case, Casey C.; Pabo, Carl O.; Campisi, Judith; Gregory, Philip D.

2003-01-01

Zinc-finger protein transcription factors (ZFP TFs) can be designed to control the expression of any desired target gene, and thus provide potential therapeutic tools for the study and treatment of disease. Here we report that a ZFP TF can repress target gene expression with single-gene specificity within the human genome. A ZFP TF repressor that binds an 18-bp recognition sequence within the promoter of the endogenous CHK2 gene gives a >10-fold reduction in CHK2 mRNA and protein. This level of repression was sufficient to generate a functional phenotype, as demonstrated by the loss of DNA damage-induced CHK2-dependent p53 phosphorylation. We determined the specificity of repression by using DNA microarrays and found that the ZFP TF repressed a single gene (CHK2) within the monitored genome in two different cell types. These data demonstrate the utility of ZFP TFs as precise tools for target validation, and highlight their potential as clinical therapeutics. PMID:14514889

Purification, crystallization, small-angle X-ray scattering and preliminary X-ray diffraction analysis of the SH2 domain of the Csk-homologous kinase.

PubMed

Gunn, Natalie J; Gorman, Michael A; Dobson, Renwick C J; Parker, Michael W; Mulhern, Terrence D

2011-03-01

The C-terminal Src kinase (Csk) and Csk-homologous kinase (CHK) are endogenous inhibitors of the proto-oncogenic Src family of protein tyrosine kinases (SFKs). Phosphotyrosyl peptide binding to their Src-homology 2 (SH2) domains activates Csk and CHK, enhancing their ability to suppress SFK signalling; however, the detailed mechanistic basis of this activation event is unclear. The CHK SH2 was expressed in Escherichia coli and the purified protein was characterized as monomeric by synchrotron small-angle X-ray scattering in-line with size-exclusion chromatography. The CHK SH2 crystallized in 0.2 M sodium bromide, 0.1 M bis-Tris propane pH 6.5 and 20% polyethylene glycol 3350 and the best crystals diffracted to ∼1.6 Å resolution. The crystals belonged to space group P2, with unit-cell parameters a=25.8, b=34.6, c=63.2 Å, β=99.4°.

Human papilloma virus type16 E6 deregulates CHK1 and sensitizes human fibroblasts to environmental carcinogens independently of its effect on p53

PubMed Central

Chen, Bo; Simpson, Dennis A.; Zhou, Yingchun; Mitra, Amritava; Mitchell, David L.; Cordeiro-Stone, Marila; Kaufmann, William K.

2015-01-01

After treatment with ultraviolet radiation (UV), human fibroblasts that express the HPV type 16 E6 oncoprotein display defects in repair of cyclobutane pyrimidine dimers, hypersensitivity to inactivation of clonogenic survival and an inability to sustain DNA replication. To determine whether these effects are specific to depletion of p53 or inactivation of its function, fibroblast lines were constructed with ectopic expression of a dominant-negative p53 allele (p53-H179Q) to inactivate function or a short-hairpin RNA (p53-RNAi) to deplete expression of p53. Only the expression of HPV16E6 sensitized fibroblasts to UV or the chemical carcinogen, benzo[a]pyrene diolepoxide I (BPDE). Carcinogen-treated cells expressing p53-H179Q or p53-RNAi were resistant to inactivation of colony formation and did not suffer replication arrest. CHK1 is a key checkpoint kinase in the response to carcinogen-induced DNA damage. Control and p53-RNAi-expressing fibroblasts displayed phosphorylation of Ser345 on CHK1 45–120 min after carcinogen treatment with a return to near baseline phosphorylation by 6 h after treatment. HPV16E6-expressing fibroblasts displayed enhanced and sustained phosphorylation of CHK1. This was associated with enhanced phosphorylation of Thr68 on CHK2 and Ser139 on H2AX, both markers of severe replication stress and DNA double strand breaks. Incubation with the phosphatase inhibitor okadaic acid produced more phosphorylation of CHK1 in UV-treated HPV16E6-expressing cells than in p53-H179Q-expressing cells suggesting that HPV16E6 may interfere with the recovery of coupled DNA replication at replication forks that are stalled at [6-4]pyrimidine-pyrimidone photoproducts and BPDE-DNA adducts. The results indicate that HPV16E6 targets a protein or proteins other than p53 to deregulate the activity of CHK1 in carcinogen-damaged cells. PMID:19411857

An insight into frequency and predictors leading psychiatric patients to visit faith healers: A hospital-based cross-sectional survey, Karachi, Pakistan.

PubMed

Khoso, Aneeta; Soomro, Rafiq Ahmed; Quraishy, Ayesha Muquim; Khan, Hammad Ali; Ismail, Saba; Nazaz, Mehrunnisa; Younus, Sana; Zainab, Saima

2018-05-01

Psychiatric illnesses have recently escalated in numbers, with patients resorting to various forms of healthcare providers, including faith healers. This delays early psychiatric treatment, resulting in further mental health deterioration of the patient. Various factors impact the mode of treatment preferred by psychiatric patients. To determine the frequency of psychiatric patients visiting faith healers, presenting at the outpatient department of Liaquat National Hospital, Karachi, Pakistan, and to explore the predictors that direct them toward visiting faith healers. This cross-sectional survey was conducted using a semi-structured pre-tested questionnaire, employing a total of 219 male and female psychiatric patients. Patients were recruited through non-random consecutive sampling technique. SPSS 18 was used for statistical analysis. About 32% of the patients had visited a faith healer in their lifetime. Frequency of current visitors declined; the most frequent reason being stated was no relief from their treatment. Students, patients of upper middle class and those coming for initial visit to a psychiatrist were more likely to visit a faith healer. Patients who knew of someone previously visiting a faith healer were less likely to have visited a faith healer. This study highlights the importance of a multisectoral approach to dealing with psychiatric patients to help in bridging the treatment gap in mental health.

Pattern of biopsy proven renal diseases at PNS SHIFA, Karachi: A cross-sectional survey

PubMed Central

Sabir, Sohail; Mubarak, Muhammed; Ul-Haq, Irfan; Bibi, Aisha

2013-01-01

Introduction: Percutaneous renal biopsy (RB) is an invaluable diagnostic procedure in patients with medical renal diseases.Objectives: To determine the pattern of biopsy proven renal disease (BPRD) from a tertiary care naval hospital in Karachi, Pakistan. Methods and Materials: All the renal biopsies in adult patients (≥18 years) performed at our hospital from 2008 to 2012 were retrospectively reviewed. The biopsies were evaluated by light microscopy and immunofluorescence. Results: A total 60 cases were analyzed. The mean age was 33.3±12.9 years (range: 18 to 72 years).The male to female ratio was 3:1. The most common indication of renal biopsy was nephrotic syndrome (43.3%), followed by renal failure (26.6%) and non-nephrotic proteinuria (23.3%). Primary glomerulonephritides (PGN) were predominant overall lesions, found in 46 (76.6%) of the total biopsies. Among PGN, the most common lesion was focal segmental glomerulosclerosis (FSGS), followed by membranous glomerulonephritis (MGN), IgA nephropathy (IgAN) and chronic sclerosing glomerulonephritis (CSGN) and a variety of rare lesions. Secondary glomerulonephritides (SGN) were found in only three (5%) cases. There were two cases of amyloidosis and one of lupus nephritis (LN). Tubulointerstitial disease (TID) and vascular disease were rare. Conclusion: This study provides information about the epidemiology of BPRD in a large tertiary care naval center in Southern Pakistan. PMID:25340152

Understanding the perceptions of children battling cancer about self and others through drawing.

PubMed

Sadruddin, Munir Moosa; Hameed-Ur-Rehman, M

2013-07-01

Childhood cancer is a stressful experience and may cause a change in the child's perception of himself/ herself, the family and the world around him/ her. This study sought to (a) explore the self-perception of children; and (b) examine the relation of children with others. The total population of the study consisted of all the children, undergoing cancer treatment at Children Cancer Hospital, located in Karachi. The participants were asked to draw a drawing on self and others. Through qualitative approach (phenomenology), themes and sub-themes were derived. Using purposive sampling, the total sample size drawn for this study was 78 children aged 7-12, receiving treatment for cancer (1st stage) at the Children Cancer Hospital, Karachi, Pakistan. The drawings of the children were categorized into facial expressions, self images and family ties. Within each category, there were sub-categories. Under facial expressions, the common emotions reflected were sadness, seriousness, anger; and pain. The self-image pictures uniformly reflected low self-esteem, especially focusing on hair loss, missing body parts. Under the category of family ties, most of the children's drawings reflected their isolation or emotional detachment from or abandonment by their family members. The study concludes that the self- image of most of the participants is deteriorated and they are socially isolated. Social and moral support can bring positive emotional development and helps to correct their self-perception.

Frequency of Non-Alcoholic Steatohepatitis on Histopathology in Patients of Type 2 Diabetes Mellitus with Duration of More than 5 Years.

PubMed

Seetlani, Naresh Kumar; Memon, Abdul Rauf; Tanveer, Sadia; Ali, Asif; Ali, Pyar; Imran, Khalid; Haroon, Hussain

2016-08-01

To determine the frequency of non-alcoholic steatohepatitis (NASH) on histopathology in patients of type 2 diabetes mellitus with duration of more than 5 years. Descriptive, cross-sectional study. Department of Medicine, Dow Medical College, Civil Hospital, Karachi, from November 2013 to April 2014. Patients with type 2 diabetes mellitus of more than 5 years duration having raised alanine transaminases level and fatty liver on ultrasonography were selected. Informed consent was obtained and liver biopsy was performed in all patients by experienced physician of Civil Hospital Karachi. All samples of biopsy were sent for histopathology. Those patients with hepatitis B, C and D and steatosis like alcoholic and hypertriglyceridemia were excluded from the study. Descriptive statistics were calculated on SPSS version 17. Out of the 262 cases, 56.49% (148/262) showed non-alcoholic steatohepatitis on the basis of histopathology. The mean age of the patients was 50.72 ±8.48 years. Median (interquartile) duration of diabetes mellitus of the cases was 9 years (15 - 4). Out of 148 NASH cases, 56.1% (83/148) were males and 43.9% (65/148) were females. Nonalcoholic steatohepatitis is an increasingly important and unrecognised spectrum of chronic liver disease associated with high prevalence of diabetes that is often overlooked and diagnosed with complications. So early recognition of these patients can prevent further complications.

Checkpoint kinase 1-induced phosphorylation of O-linked β-N-acetylglucosamine transferase regulates the intermediate filament network during cytokinesis.

PubMed

Li, Zhe; Li, Xueyan; Nai, Shanshan; Geng, Qizhi; Liao, Ji; Xu, Xingzhi; Li, Jing

2017-12-01

Checkpoint kinase 1 (Chk1) is a kinase instrumental for orchestrating DNA replication, DNA damage checkpoints, the spindle assembly checkpoint, and cytokinesis. Despite Chk1's pivotal role in multiple cellular processes, many of its substrates remain elusive. Here, we identified O- linked β- N -acetylglucosamine ( O -GlcNAc)-transferase (OGT) as one of Chk1's substrates. We found that Chk1 interacts with and phosphorylates OGT at Ser-20, which not only stabilizes OGT, but also is required for cytokinesis. Phospho-specific antibodies of OGT-pSer-20 exhibited specific signals at the midbody of the cell, consistent with midbody localization of OGT as reported previously. Moreover, phospho-deficient OGT (S20A) cells attenuated cellular O -GlcNAcylation levels and also reduced phosphorylation of Ser-71 in the cytoskeletal protein vimentin, a modification critical for severing vimentin filament during cytokinesis. Consequently, elongated vimentin bridges were observed in cells depleted of OGT via an si OGT- based approach. Lastly, expression of plasmids resistant to si OGT efficiently rescued the vimentin bridge phenotype, but the OGT-S20A rescue plasmids did not. Our results suggest a Chk1-OGT-vimentin pathway that regulates the intermediate filament network during cytokinesis. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Using SERVQUAL for assessing and improving patient satisfaction at a rural health facility in Pakistan.

PubMed

Shaikh, B T; Mobeen, N; Azam, S I; Rabbani, F

2008-01-01

A cross-sectional study of patient satisfaction with care was conducted over a period of 1 year from March 2004 to March 2005 in a secondary-level hospital in a peri-urban area of Karachi, Pakistan. Using the SERVQUAL tool and exit interviews, data were collected quarterly from a total of 1533 patients. Results sharing and capacity-building workshops were arranged during the 4 phases of the survey to sensitize the staff of the hospital to work towards improving patient satisfaction. The level of satisfaction of the patients with the outpatient health services provided showed a gradual increase from 34.4% to 82.0% over the 1-year period.

Induction process of trainees in pathology residency

PubMed Central

Siddiqui, Imran; Ali, Natasha

2016-01-01

This article describes the evolution of the induction process of pathology residency at The Aga Khan University hospital. The Department of Postgraduate Medical Education was established in 1985. The induction process is an exhaustive exercise that includes an admission test held simultaneously in Karachi, Hyderabad, Lahore, and Rawalpindi, followed by an interview of the shortlisted candidates. The pathology residency program was started 25 years ago and since then the induction process has undergone major changes with the course of time. PMID:27313487

Impaired tissue growth is mediated by checkpoint kinase 1 (CHK1) in the integrated stress response

PubMed Central

Malzer, Elke; Daly, Marie-Louise; Moloney, Aileen; Sendall, Timothy J.; Thomas, Sally E.; Ryder, Edward; Ryoo, Hyung Don; Crowther, Damian C.; Lomas, David A.; Marciniak, Stefan J.

2010-01-01

The integrated stress response (ISR) protects cells from numerous forms of stress and is involved in the growth of solid tumours; however, it is unclear how the ISR acts on cellular proliferation. We have developed a model of ISR signalling with which to study its effects on tissue growth. Overexpression of the ISR kinase PERK resulted in a striking atrophic eye phenotype in Drosophila melanogaster that could be rescued by co-expressing the eIF2α phosphatase GADD34. A genetic screen of 3000 transposon insertions identified grapes, the gene that encodes the Drosophila orthologue of checkpoint kinase 1 (CHK1). Knockdown of grapes by RNAi rescued eye development despite ongoing PERK activation. In mammalian cells, CHK1 was activated by agents that induce ER stress, which resulted in a G2 cell cycle delay. PERK was both necessary and sufficient for CHK1 activation. These findings indicate that non-genotoxic misfolded protein stress accesses DNA-damage-induced cell cycle checkpoints to couple the ISR to cell cycle arrest. PMID:20682638

In Silico Exploration of 1,7-Diazacarbazole Analogs as Checkpoint Kinase 1 Inhibitors by Using 3D QSAR, Molecular Docking Study, and Molecular Dynamics Simulations.

PubMed

Gao, Xiaodong; Han, Liping; Ren, Yujie

2016-05-05

Checkpoint kinase 1 (Chk1) is an important serine/threonine kinase with a self-protection function. The combination of Chk1 inhibitors and anti-cancer drugs can enhance the selectivity of tumor therapy. In this work, a set of 1,7-diazacarbazole analogs were identified as potent Chk1 inhibitors through a series of computer-aided drug design processes, including three-dimensional quantitative structure-activity relationship (3D-QSAR) modeling, molecular docking, and molecular dynamics simulations. The optimal QSAR models showed significant cross-validated correlation q² values (0.531, 0.726), fitted correlation r² coefficients (higher than 0.90), and standard error of prediction (less than 0.250). These results suggested that the developed models possess good predictive ability. Moreover, molecular docking and molecular dynamics simulations were applied to highlight the important interactions between the ligand and the Chk1 receptor protein. This study shows that hydrogen bonding and electrostatic forces are key interactions that confer bioactivity.

Activation of DNA damage repair pathways by murine polyomavirus.

PubMed

Heiser, Katie; Nicholas, Catherine; Garcea, Robert L

2016-10-01

Nuclear replication of DNA viruses activates DNA damage repair (DDR) pathways, which are thought to detect and inhibit viral replication. However, many DNA viruses also depend on these pathways in order to optimally replicate their genomes. We investigated the relationship between murine polyomavirus (MuPyV) and components of DDR signaling pathways including CHK1, CHK2, H2AX, ATR, and DNAPK. We found that recruitment and retention of DDR proteins at viral replication centers was independent of H2AX, as well as the viral small and middle T-antigens. Additionally, infectious virus production required ATR kinase activity, but was independent of CHK1, CHK2, or DNAPK signaling. ATR inhibition did not reduce the total amount of viral DNA accumulated, but affected the amount of virus produced, indicating a defect in virus assembly. These results suggest that MuPyV may utilize a subset of DDR proteins or non-canonical DDR signaling pathways in order to efficiently replicate and assemble. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Chk1-induced CCNB1 overexpression promotes cell proliferation and tumor growth in human colorectal cancer

PubMed Central

Fang, Yifeng; Yu, Hong; Liang, Xiao; Xu, Junfen; Cai, Xiujun

2014-01-01

The high morbidity and mortality of colorectal cancer pose a significant public health problem worldwide. Here we assessed the pro-cancer efficacy and mechanism of action of CCNB1 in different colorectal cancer cells. We provided evidence that CCNB1 mRNA and protein level were upregulated in a subset of human colorectal tumors, and positively correlated with Chk1 expression. Repression of Chk1 caused a significant decrease in cell proliferation and CCNB1 protein expression in colorectal cancer cells. Furthermore, downregulation of CCNB1 impaired colorectal cancer proliferation in vitro and tumor growth in vivo. Specifically, suppression of CCNB1 caused a strong G2/M phase arrest in both HCT116 and SW480 cells, interfering with the expression of cdc25c and CDK1. Additionally, CCNB1 inhibition induced apoptotic death in certain colorectal cancer cells. Together, these results suggest that CCNB1 is activated by Chk1, exerts its oncogenic role in colorectal cancer cells, and may play a key role in the development of a novel therapeutic approach against colorectal cancer. PMID:24971465

Retrospective study of cancer types in different ethnic groups and genders at Karachi.

PubMed

Khaliq, Sheikh Abdul; Naqvi, Syed Baqir; Fatima, Anab

2013-12-01

Retrospective study of Cancer types in different ethnic groups & genders determines the pattern of cancers in different ethnic groups & genders during the last eight years reported in Oncology wards of hospitals of Karachi, Pakistan. Every single one male & female case with histologically and cytologically established cancer was enrolled from January 2003 to December 2010. Data for all patients were collected retrospectively by patient's file & charts, which represents the population of Karachi, Interior Sindh & Balochistan. 5134 patients (Male = 2432 / Female = 2702) investigated for their diagnosis of cancer type, ethnicity, age & gender. Classification of malignancy was done according to the International Classification of Disease coding system by W.H.O (ICD-10). The statistical analysis was performed for mean, standard error & proportions for ethnic groups & genders. Proportionately 47.37% males and among which major ethnic groups 17% Sindhi, 17% Immigrant, 4% Baloch, 3% Pukhtoon, ≈ 4% Punjabi, 1% Siraiki, 2% Minorities and 52.62% females, in which 16% Sindhi, 21% Immigrant, 4% Baloch 3% Pukhtoon, 5% Punjabi, 1% Siraiki, 3% Minorities. Mean age of males = 45.75 years, SE ± 0.227 and for females = 44.07, SE ± 0.183. The three most occurring tumors in all cancers of male were found Head & Neck, Adenoma/Carcinoma of Glands & Body cavity membranes, GIT, and females Breast, Head & Neck, Adenoma/Carcinoma of Glands & Body cavity membranes, GIT. The analysis of data indicates Head & Neck is most common cancer among male, in the similar way Breast cancer is the most common malignancy among female.

Uncontrolled diabetes mellitus: prevalence and risk factors among people with type 2 diabetes mellitus in an Urban District of Karachi, Pakistan.

PubMed

Siddiqui, Fahad Javaid; Avan, Bilal Iqbal; Mahmud, Sadia; Nanan, Debra J; Jabbar, Abdul; Assam, Pryseley Nkouibert

2015-01-01

This study aimed to explore the prevalence of, and factors associated with, uncontrolled diabetes mellitus (UDM) in a community setting in Pakistan. A single-center, cross-sectional study, conducted in a community-based specialized care center (SCC) for diabetes in District Central Karachi, in 2003, registered 452 type 2 DM participants, tested for HbA1c and interviewed face-to-face for other information. Logistic regression analysis was conducted to identify factors associated with UDM. Prevalence of UDM among diabetes patients was found to be 38.9% (95% CI: 34.4-43.4%). Multivariable logistic regression model analysis indicated that age <50 years (OR: 1.9; 95% CI: 1.2-2.9), being diagnosed in a hospital (vs. a clinic) (OR: 1.8; 95% CI: 1.1-2.8), diabetes information from a doctor or nurse only (vs. multiple sources) (OR: 1.8; 95% CI: 1.2-2.9), higher monthly treatment cost (OR: 1.3; 95% CI: 1.1-1.6; for every extra 500 PKR), and higher consumption of tea (OR: 1.5; 95% CI: 1.0-2.2; for every 2 extra cups) were independently associated with UDM. The prevalence of UDM was approximately 39% among persons with type 2 diabetes visiting a community based SCC for diabetes. Modifiable risk factors such as sources of diabetes information and black tea consumption can be considered as potential targets of interventions in Karachi. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Phosphatase Complex Pph3/Psy2 Is Involved in Regulation of Efficient Non-Homologous End-Joining Pathway in the Yeast Saccharomyces cerevisiae

PubMed Central

Omidi, Katayoun; Hooshyar, Mohsen; Jessulat, Matthew; Samanfar, Bahram; Sanders, Megan; Burnside, Daniel; Pitre, Sylvain; Schoenrock, Andrew; Xu, Jianhua; Babu, Mohan; Golshani, Ashkan

2014-01-01

One of the main mechanisms for double stranded DNA break (DSB) repair is through the non-homologous end-joining (NHEJ) pathway. Using plasmid and chromosomal repair assays, we showed that deletion mutant strains for interacting proteins Pph3p and Psy2p had reduced efficiencies in NHEJ. We further observed that this activity of Pph3p and Psy2p appeared linked to cell cycle Rad53p and Chk1p checkpoint proteins. Pph3/Psy2 is a phosphatase complex, which regulates recovery from the Rad53p DNA damage checkpoint. Overexpression of Chk1p checkpoint protein in a parallel pathway to Rad53p compensated for the deletion of PPH3 or PSY2 in a chromosomal repair assay. Double mutant strains Δpph3/Δchk1 and Δpsy2/Δchk1 showed additional reductions in the efficiency of plasmid repair, compared to both single deletions which is in agreement with the activity of Pph3p and Psy2p in a parallel pathway to Chk1p. Genetic interaction analyses also supported a role for Pph3p and Psy2p in DNA damage repair, the NHEJ pathway, as well as cell cycle progression. Collectively, we report that the activity of Pph3p and Psy2p further connects NHEJ repair to cell cycle progression. PMID:24498054

Checkpoint kinase 1 inhibition sensitises transformed cells to dihydroorotate dehydrogenase inhibition

PubMed Central

Arnould, Stéphanie; Rodier, Geneviève; Matar, Gisèle; Vincent, Charles; Pirot, Nelly; Delorme, Yoann; Berthet, Charlène; Buscail, Yoan; Noël, Jean Yohan; Lachambre, Simon; Jarlier, Marta; Bernex, Florence; Delpech, Hélène; Vidalain, Pierre Olivier; Janin, Yves L.; Theillet, Charles; Sardet, Claude

2017-01-01

Reduction in nucleotide pools through the inhibition of mitochondrial enzyme dihydroorotate dehydrogenase (DHODH) has been demonstrated to effectively reduce cancer cell proliferation and tumour growth. The current study sought to investigate whether this antiproliferative effect could be enhanced by combining Chk1 kinase inhibition. The pharmacological activity of DHODH inhibitor teriflunomide was more selective towards transformed mouse embryonic fibroblasts than their primary or immortalised counterparts, and this effect was amplified when cells were subsequently exposed to PF477736 Chk1 inhibitor. Flow cytometry analyses revealed substantial accumulations of cells in S and G2/M phases, followed by increased cytotoxicity which was characterised by caspase 3-dependent induction of cell death. Associating PF477736 with teriflunomide also significantly sensitised SUM159 and HCC1937 human triple negative breast cancer cell lines to dihydroorotate dehydrogenase inhibition. The main characteristic of this effect was the sustained accumulation of teriflunomide-induced DNA damage as cells displayed increased phospho serine 139 H2AX (γH2AX) levels and concentration-dependent phosphorylation of Chk1 on serine 345 upon exposure to the combination as compared with either inhibitor alone. Importantly a similar significant increase in cell death was observed upon dual siRNA mediated depletion of Chk1 and DHODH in both murine and human cancer cell models. Altogether these results suggest that combining DHODH and Chk1 inhibitions may be a strategy worth considering as a potential alternative to conventional chemotherapies. PMID:29221122

PERK inhibits DNA replication during the Unfolded Protein Response via Claspin and Chk1.

PubMed

Cabrera, E; Hernández-Pérez, S; Koundrioukoff, S; Debatisse, M; Kim, D; Smolka, M B; Freire, R; Gillespie, D A

2017-02-02

Stresses such as hypoxia, nutrient deprivation and acidification disturb protein folding in the endoplasmic reticulum (ER) and activate the Unfolded Protein Response (UPR) to trigger adaptive responses through the effectors, PERK, IRE1 and ATF6. Most of these responses relate to ER homoeostasis; however, here we show that the PERK branch of the UPR also controls DNA replication. Treatment of cells with the non-genotoxic UPR agonist thapsigargin led to a rapid inhibition of DNA synthesis that was attributable to a combination of DNA replication fork slowing and reduced replication origin firing. DNA synthesis inhibition was dependent on the UPR effector PERK and was associated with phosphorylation of the checkpoint adaptor protein Claspin and activation of the Chk1 effector kinase, both of which occurred in the absence of detectable DNA damage. Remarkably, thapsigargin did not inhibit bulk DNA synthesis or activate Chk1 in cells depleted of Claspin, or when Chk1 was depleted or subject to chemical inhibition. In each case thapsigargin-resistant DNA synthesis was due to an increase in replication origin firing that compensated for reduced fork progression. Taken together, our results unveil a new aspect of PERK function and previously unknown roles for Claspin and Chk1 as negative regulators of DNA replication in the absence of genotoxic stress. Because tumour cells proliferate in suboptimal environments, and frequently show evidence of UPR activation, this pathway could modulate the response to DNA replication-targeted chemotherapies.

DNA Binding and Phosphorylation Regulate the Core Structure of the NF-κB p50 Transcription Factor

NASA Astrophysics Data System (ADS)

Vonderach, Matthias; Byrne, Dominic P.; Barran, Perdita E.; Eyers, Patrick A.; Eyers, Claire E.

2018-06-01

The NF-κB transcription factors are known to be extensively phosphorylated, with dynamic site-specific modification regulating their ability to dimerize and interact with DNA. p50, the proteolytic product of p105 (NF-κB1), forms homodimers that bind DNA but lack intrinsic transactivation function, functioning as repressors of transcription from κB promoters. Here, we examine the roles of specific phosphorylation events catalysed by either protein kinase A (PKAc) or Chk1, in regulating the functions of p50 homodimers. LC-MS/MS analysis of proteolysed p50 following in vitro phosphorylation allows us to define Ser328 and Ser337 as PKAc- and Chk1-mediated modifications, and pinpoint an additional four Chk1 phosphosites: Ser65, Thr152, Ser242 and Ser248. Native mass spectrometry (MS) reveals Chk1- and PKAc-regulated disruption of p50 homodimer formation through Ser337. Additionally, we characterise the Chk1-mediated phosphosite, Ser242, as a regulator of DNA binding, with a S242D p50 phosphomimetic exhibiting a > 10-fold reduction in DNA binding affinity. Conformational dynamics of phosphomimetic p50 variants, including S242D, are further explored using ion-mobility MS (IM-MS). Finally, comparative theoretical modelling with experimentally observed p50 conformers, in the absence and presence of DNA, reveals that the p50 homodimer undergoes conformational contraction during electrospray ionisation that is stabilised by complex formation with κB DNA.

HTLV-1 Tax Oncoprotein Subverts the Cellular DNA Damage Response via Binding to DNA-dependent Protein Kinase*S⃞

PubMed Central

Durkin, Sarah S.; Guo, Xin; Fryrear, Kimberly A.; Mihaylova, Valia T.; Gupta, Saurabh K.; Belgnaoui, S. Mehdi; Haoudi, Abdelali; Kupfer, Gary M.; Semmes, O. John

2008-01-01

Human T-cell leukemia virus type-1 is the causative agent for adult T-cell leukemia. Previous research has established that the viral oncoprotein Tax mediates the transformation process by impairing cell cycle control and cellular response to DNA damage. We showed previously that Tax sequesters huChk2 within chromatin and impairs the response to ionizing radiation. Here we demonstrate that DNA-dependent protein kinase (DNA-PK) is a member of the Tax·Chk2 nuclear complex. The catalytic subunit, DNA-PKcs, and the regulatory subunit, Ku70, were present. Tax-containing nuclear extracts showed increased DNA-PK activity, and specific inhibition of DNA-PK prevented Tax-induced activation of Chk2 kinase activity. Expression of Tax induced foci formation and phosphorylation of H2AX. However, Tax-induced constitutive signaling of the DNA-PK pathway impaired cellular response to new damage, as reflected in suppression of ionizing radiation-induced DNA-PK phosphorylation and γH2AX stabilization. Tax co-localized with phospho-DNA-PK into nuclear speckles and a nuclear excluded Tax mutant sequestered endogenous phospho-DNA-PK into the cytoplasm, suggesting that Tax interaction with DNA-PK is an initiating event. We also describe a novel interaction between DNA-PK and Chk2 that requires Tax. We propose that Tax binds to and stabilizes a protein complex with DNA-PK and Chk2, resulting in a saturation of DNA-PK-mediated damage repair response. PMID:18957425

Mechanistic Distinctions between CHK1 and WEE1 Inhibition Guide the Scheduling of Triple Therapy with Gemcitabine.

PubMed

Koh, Siang-Boon; Wallez, Yann; Dunlop, Charles R; Bernaldo de Quirós Fernández, Sandra; Bapiro, Tashinga E; Richards, Frances M; Jodrell, Duncan I

2018-06-01

Combination of cytotoxic therapy with emerging DNA damage response inhibitors (DDRi) has been limited by tolerability issues. However, the goal of most combination trials has been to administer DDRi with standard-of-care doses of chemotherapy. We hypothesized that mechanism-guided treatment scheduling could reduce the incidence of dose-limiting toxicities and enable tolerable multitherapeutic regimens. Integrative analyses of mathematical modeling and single-cell assays distinguished the synergy kinetics of WEE1 inhibitor (WEE1i) from CHEK1 inhibitor (CHK1i) by potency, spatiotemporal perturbation, and mitotic effects when combined with gemcitabine. These divergent properties collectively supported a triple-agent strategy, whereby a pulse of gemcitabine and CHK1i followed by WEE1i durably suppressed tumor cell growth. In xenografts, CHK1i exaggerated replication stress without mitotic CDK hyperactivation, enriching a geminin-positive subpopulation and intratumoral gemcitabine metabolite. Without overt toxicity, addition of WEE1i to low-dose gemcitabine and CHK1i was most effective in tumor control compared with single and double agents. Overall, our work provides quantitative insights into the mechanisms of DDRi chemosensitization, leading to the rational development of a tolerable multitherapeutic regimen. Significance: Multiple lines of mechanistic insight regarding DNA damage response inhibitors rationally guide the preclinical development of a tolerable multitherapeutic regimen. Graphical Abstract: http://cancerres.aacrjournals.org/content/canres/78/11/3054/F1.large.jpg Cancer Res; 78(11); 3054-66. ©2018 AACR . ©2018 American Association for Cancer Research.

Phosphatase complex Pph3/Psy2 is involved in regulation of efficient non-homologous end-joining pathway in the yeast Saccharomyces cerevisiae.

PubMed

Omidi, Katayoun; Hooshyar, Mohsen; Jessulat, Matthew; Samanfar, Bahram; Sanders, Megan; Burnside, Daniel; Pitre, Sylvain; Schoenrock, Andrew; Xu, Jianhua; Babu, Mohan; Golshani, Ashkan

2014-01-01

One of the main mechanisms for double stranded DNA break (DSB) repair is through the non-homologous end-joining (NHEJ) pathway. Using plasmid and chromosomal repair assays, we showed that deletion mutant strains for interacting proteins Pph3p and Psy2p had reduced efficiencies in NHEJ. We further observed that this activity of Pph3p and Psy2p appeared linked to cell cycle Rad53p and Chk1p checkpoint proteins. Pph3/Psy2 is a phosphatase complex, which regulates recovery from the Rad53p DNA damage checkpoint. Overexpression of Chk1p checkpoint protein in a parallel pathway to Rad53p compensated for the deletion of PPH3 or PSY2 in a chromosomal repair assay. Double mutant strains Δpph3/Δchk1 and Δpsy2/Δchk1 showed additional reductions in the efficiency of plasmid repair, compared to both single deletions which is in agreement with the activity of Pph3p and Psy2p in a parallel pathway to Chk1p. Genetic interaction analyses also supported a role for Pph3p and Psy2p in DNA damage repair, the NHEJ pathway, as well as cell cycle progression. Collectively, we report that the activity of Pph3p and Psy2p further connects NHEJ repair to cell cycle progression.

Deliberate self-harm in the emergency department: experience from Karachi, Pakistan.

PubMed

Shahid, Muhammad; Khan, Murad M; Saleem Khan, Muhammad; Jamal, Yasir; Badshah, Aaref; Rehmani, Rifat

2009-01-01

Suicidal behavior is an understudied subject in Pakistan, a South-Asian developing country with a predominantly Muslim population. This study examined the characteristics and management of patients presenting with Deliberate Self-Harm (DSH) to the Emergency Department (ED) of a tertiary care teaching hospital in Karachi, Pakistan. A retrospective chart review of all patients (n = 98), over a period of 12 months was carried out. The demographic details of patients; method of DSH and, if drugs were used, their type, route, and quantity; reason for DSH; past psychiatric history; and outcome were recorded. The mean age of subjects was 23.5 years. The majority of patients were female; most had used drugs for DSH. After initial treatment in the ED, 34 patients were admitted to medical wards for further treatment, 12 were discharged from ED, while 52 patients left against medical advice. The main reasons for leaving against medical advice were financial constraints and fear of legal issues. Seven patients had at least one previous episode of DSH. Patients who left the ED without psychosocial assessment are at increased risk for repetition of DSH as well as suicide.

The contribution of DNA replication stress marked by high-intensity, pan-nuclear γH2AX staining to chemosensitization by CHK1 and WEE1 inhibitors.

PubMed

Parsels, Leslie A; Parsels, Joshua D; Tanska, Daria M; Maybaum, Jonathan; Lawrence, Theodore S; Morgan, Meredith A

2018-06-12

Small molecule inhibitors of the checkpoint proteins CHK1 and WEE1 are currently in clinical development in combination with the antimetabolite gemcitabine. It is unclear, however, if there is a therapeutic advantage to CHK1 vs. WEE1 inhibition for chemosensitization. The goals of this study were to directly compare the relative efficacies of the CHK1 inhibitor MK8776 and the WEE1 inhibitor AZD1775 to sensitize pancreatic cancer cell lines to gemcitabine and to identify pharmacodynamic biomarkers predictive of chemosensitization. Cells treated with gemcitabine and either MK8776 or AZD1775 were first assessed for clonogenic survival. With the exception of the homologous recombination-defective Capan1 cells, which were relatively insensitive to MK8776, we found that these cell lines were similarly sensitized to gemcitabine by CHK1 or WEE1 inhibition. The abilities of either the CDK1/2 inhibitor roscovitine or exogenous nucleosides to prevent MK8776 or AZD1775-mediated chemosensitization, however, were both inhibitor-dependent and variable among cell lines. Given the importance of DNA replication stress to gemcitabine chemosensitization, we next assessed high-intensity, pan-nuclear γH2AX staining as a pharmacodynamic marker for sensitization. In contrast to total γH2AX, aberrant mitotic entry or sub-G1 DNA content, high-intensity γH2AX staining correlated with chemosensitization by either MK8776 or AZD1775 (R 2 0.83 - 0.53). In summary, we found that MK8776 and AZD1775 sensitize to gemcitabine with similar efficacy. Furthermore, our results suggest that the effects of CHK1 and WEE1 inhibition on gemcitabine-mediated replication stress best predict chemosensitization and support the use of high-intensity or pan-nuclear γH2AX staining as a marker for therapeutic response.

Male hypogonadism at a tertiary care hospital in Karachi, Pakistan.

PubMed

Ram, Nanik; Asghar, Ali; Hashmi, Fauzan; Islam, Najmul

2012-01-01

Male hypogonadism is defined as 'inadequate gonadal function, manifested by deficiency in gametogenesis and/or secretion of gonadal hormones'. Signs and symptoms of hypogonadism depend primarily on the age of onset. It can be classified according to the site primarily involved: the gonads, the hypothalamus, or the pituitary gland. The objective this study was to determine the presentation and aetiology of male hypogonadism seen in a tertiary care hospital. This cross-sectional study was conducted at Endocrine Clinics, Aga Khan University Hospital Karachi. Data of male patients with hypogonadism who attended clinics during January 2009 to August 2011 were reviewed. All male patients with clinical and biochemical evidence of hypogonadism were included in the study. Patients with Diabetes Mellitus, Metabolic Syndrome, Andropause, AIDS, Chronic Renal Failure, and Cirrhosis were excluded. Mean +/- SD were computed for quantitative variables. Frequency and percentages were computed for qualitative variables. Aetiology of male hypogonadism was categorised as primary and secondary hypogonadism. A total of 85 patients with male hypogonadism attended the endocrine clinic. Mean age of patients was 25 +/- 10 years. Clinical presentations were small genitalia (65%), absent secondary sexual characteristics (53%), not attained puberty (47%), infertility (53%), erectile dysfunction (41%) and loss of libido (29%). Seventy-three (86%) patients had hypogonadotrophic hypogonadism (secondary hypogonadism) and 12 (14%) patients had hypergonadotrophic hypogonadism (primary hypogonadism). Among the patients with hypogonadotrophic hypogonadism 38 had idiopathic hypogonadotrophic hypogonadsim, 7 had pituitary adenoma, 6 had empty sella syndrome, 3 had Kallman's syndrome, and 1 patient had haemosiderosis due to thalassaemia major; 18 patients did not undergo brain imaging. Small genitalia, absent secondary sexual characteristics and infertility were the main presenting features of hypogonad men. Majority of patients had hypogonadotrophic hypogonadsim.

Association of depression with treatment outcomes in Type 2 Diabetes Mellitus: a cross-sectional study from Karachi, Pakistan.

PubMed

Zuberi, Saman I; Syed, Ehsan U; Bhatti, Junaid A

2011-02-15

To assess the associations of depression with glycemic control and compliance to self-care activities in adult patients with Type 2 Diabetes Mellitus This cross-sectional study was conducted at a tertiary-care hospital in Karachi (Aga Khan University Hospital). Equal numbers of depressed and non-depressed patients were consecutively recruited from the diabetic clinic. Information on demographic and clinical characteristics was collected in face-to-face interviews and from medical records. Hospital Anxiety Depression Scale (HADS) was used to measure depression. Associations of depressed status (HADS ≥ 8) with poor glycemic control (Hemoglobin A1c level ≥ 7%) and compliance to self-care activities were assessed by logistic regression analyses. A total of 286 patients were included in this study with a male-female ratio of 1.2:1. Mean age was 52 years and in 64.7% of them, the duration of diabetes was more than 3 years. Depressed patients were more likely to be female (adjusted odds ratio [OR] = 1.88; 95% confidence interval [95%CI] = 1.07-3.31), had a family history of diabetes (OR = 2.64; 95%CI = 1.26-5.55), and poor glycemic control (OR = 5.57; 95%CI = 2.88-10.76) compared with non-depressed patients. Depression was also associated with low compliance to self-care activities such as taking dose as advised (OR = 0.32; 95%CI = 0.14-0.73), dietary restrictions (OR = 0.45; 95%CI = 0.26-0.79) and foot care (OR = 0.38; 95%CI = 0.18-0.83). Adult patients with Type 2 Diabetes who have depression were more likely to have poor glycemic control and lower compliance to self-care activities, and they might need particular attention during follow-up visits.

Death certificate completion skills of hospital physicians in a developing country.

PubMed

Haque, Ahmed Suleman; Shamim, Kanza; Siddiqui, Najm Hasan; Irfan, Muhammad; Khan, Javaid Ahmed

2013-06-06

Death certificates (DC) can provide valuable health status data regarding disease incidence, prevalence and mortality in a community. It can guide local health policy and help in setting priorities. Incomplete and inaccurate DC data, on the other hand, can significantly impair the precision of a national health information database. In this study we evaluated the accuracy of death certificates at a tertiary care teaching hospital in a Karachi, Pakistan. A retrospective study conducted at Aga Khan University Hospital, Karachi, Pakistan for a period of six months. Medical records and death certificates of all patients who died under adult medical service were studied. The demographic characteristics, administrative details, co-morbidities and cause of death from death certificates were collected using an approved standardized form. Accuracy of this information was validated using their medical records. Errors in the death certificates were classified into six categories, from 0 to 5 according to increasing severity; a grade 0 was assigned if no errors were identified, and 5, if an incorrect cause of death was attributed or placed in an improper sequence. 223 deaths occurred during the study period. 9 certificates were not accessible and 12 patients had incomplete medical records. 202 certificates were finally analyzed. Most frequent errors pertaining to patients' demographics (92%) and cause/s of death (87%) were identified. 156 (77%) certificates had 3 or more errors and 124 (62%) certificates had a combination of errors that significantly changed the death certificate interpretation. Only 1% certificates were error free. A very high rate of errors was identified in death certificates completed at our academic institution. There is a pressing need for appropriate intervention/s to resolve this important issue.

International comparative study of childhood malignancy comparative study of pediatric malignancy between Kurume and Karachi (K-K Project 1991).

PubMed

Shakoor, A; Murakami, T; Yamashita, F

1991-01-01

A study was undertaken to compare Pediatric Malignancy at Kurume (Japan) and Karachi (Pakistan) with reference to international data collected over the years, in order to identify essential differences between developed and developing conditions and factors influencing the etio-pathogenesis of pediatric cancer. The study was retrospective encompassing all types of cancer in children over a period of three years i-e 1988-1990. Essential factors related to present study were: 1. The population of Karachi is about 10 million while that of Kurume is only half a million. 2. Socio-economic conditions: The average socio-economic condition of people in Karachi is poor while in Kurume it appears to be good. 3. Educational status: Only 25% people in Karachi are educated beyond middle class while Kurume reveals a 100% education up to high school level. 4. Environmental conditions: The environmental conditions of Kurume and surrounding areas are very clean and free from pollution, sewage problems and traffic hazards. Karachi and its surroundings on the other hand pose very serious air and water industries! It was concluded that whereas genetic predisposition predominates, the environmental conditions, educational and socio-economic status of a society immensely influence the pattern and trends of pediatric carcinogenesis.

Effectiveness of training on de-escalation of violence and management of aggressive behavior faced by health care providers in a public sector hospital of Karachi

PubMed Central

Baig, Lubna; Tanzil, Sana; Shaikh, Shiraz; Hashmi, Ibrahim; Khan, Muhammad Arslan; Polkowski, Maciej

2018-01-01

Background & Objective: Considering high burden of violence against healthcare workers in Pakistan APPNA Institute of Public Health developed a training to prevent reactive violence among healthcare providers. The purpose of this training was to equip healthcare providers with skills essential to control aggressive behaviors and prevent verbal and non-verbal violence in workplace settings. This study assesses the effectiveness of training in prevention, de-escalation and management of violence in healthcare settings. Methods: A quasi-experimental study was conducted in October, 2016 using mixed method concurrent embedded design. The study assessed effectiveness of de-escalation trainings among health care providers working in emergency and gynecology and obstetrics departments of two teaching hospitals in Karachi. Quantitative assessment was done through structured interviews and qualitative through Focus Group Discussions. Healthcare providers` confidence in coping with patient aggression was also measured using a standard validated tool”. Results: The overall self-perceived mean score of Confidence in Coping with Patient Aggression Instrument “(CCPAI)” scale was significantly higher in intervention group (Mean= 27.49, SD=3.53) as compared to control group (Mean= 23.92, SD=4.52) (p<0.001). No statistically significant difference was observed between intervention and control groups with regard to frequency of violence faced by HCPs post training and major perpetrators of violence.. Conclusion: De-escalation of violence training was effective in improving confidence of healthcare providers in coping with patient aggression. PMID:29805396

Identification of ATR-Chk1 pathway inhibitors that selectively target p53-deficient cells without directly suppressing ATR catalytic activity

PubMed Central

Kawasumi, Masaoki; Bradner, James E.; Tolliday, Nicola; Thibodeau, Renee; Sloan, Heather; Brummond, Kay M.; Nghiem, Paul

2014-01-01

Resistance to DNA-damaging chemotherapy is a barrier to effective treatment that appears to be augmented by p53 functional deficiency in many cancers. In p53-deficient cells where the G1/S checkpoint is compromised, cell viability after DNA damage relies upon intact intra-S and G2/M checkpoints mediated by the ATR and Chk1 kinases. Thus, a logical rationale to sensitize p53-deficient cancers to DNA-damaging chemotherapy is through the use of ATP-competitive inhibitors of ATR or Chk1. To discover small molecules that may act on uncharacterized components of the ATR pathway, we performed a phenotype-based screen of 9,195 compounds for their ability to inhibit hydroxyurea-induced phosphorylation of Ser345 on Chk1, known to be a critical ATR substrate. This effort led to the identification of four small-molecule compounds, three of which were derived from known bioactive library (anthothecol, dihydrocelastryl, and erysolin) and one of which was a novel synthetic compound termed MARPIN. These compounds all inhibited ATR-selective phosphorylation and sensitized p53-deficient cancer cells to DNA-damaging agents in vitro and in vivo. Notably, these compounds did not inhibit ATR catalytic activity in vitro, unlike typical ATP-competitive inhibitors, but acted in a mechanistically distinct manner to disable ATR-Chk1 function. Our results highlight a set of novel molecular probes to further elucidate druggable mechanisms to improve cancer therapeutic responses produced by DNA-damaging drugs. PMID:25336189

Identification of ATR-Chk1 pathway inhibitors that selectively target p53-deficient cells without directly suppressing ATR catalytic activity.

PubMed

Kawasumi, Masaoki; Bradner, James E; Tolliday, Nicola; Thibodeau, Renee; Sloan, Heather; Brummond, Kay M; Nghiem, Paul

2014-12-15

Resistance to DNA-damaging chemotherapy is a barrier to effective treatment that appears to be augmented by p53 functional deficiency in many cancers. In p53-deficient cells in which the G1-S checkpoint is compromised, cell viability after DNA damage relies upon intact intra-S and G2-M checkpoints mediated by the ATR (ataxia telangiectasia and Rad3 related) and Chk1 kinases. Thus, a logical rationale to sensitize p53-deficient cancers to DNA-damaging chemotherapy is through the use of ATP-competitive inhibitors of ATR or Chk1. To discover small molecules that may act on uncharacterized components of the ATR pathway, we performed a phenotype-based screen of 9,195 compounds for their ability to inhibit hydroxyurea-induced phosphorylation of Ser345 on Chk1, known to be a critical ATR substrate. This effort led to the identification of four small-molecule compounds, three of which were derived from known bioactive library (anthothecol, dihydrocelastryl, and erysolin) and one of which was a novel synthetic compound termed MARPIN. These compounds all inhibited ATR-selective phosphorylation and sensitized p53-deficient cancer cells to DNA-damaging agents in vitro and in vivo. Notably, these compounds did not inhibit ATR catalytic activity in vitro, unlike typical ATP-competitive inhibitors, but acted in a mechanistically distinct manner to disable ATR-Chk1 function. Our results highlight a set of novel molecular probes to further elucidate druggable mechanisms to improve cancer therapeutic responses produced by DNA-damaging drugs. ©2014 American Association for Cancer Research.

DNA Binding and Phosphorylation Regulate the Core Structure of the NF-κB p50 Transcription Factor.

PubMed

Vonderach, Matthias; Byrne, Dominic P; Barran, Perdita E; Eyers, Patrick A; Eyers, Claire E

2018-06-05

The NF-κB transcription factors are known to be extensively phosphorylated, with dynamic site-specific modification regulating their ability to dimerize and interact with DNA. p50, the proteolytic product of p105 (NF-κB1), forms homodimers that bind DNA but lack intrinsic transactivation function, functioning as repressors of transcription from κB promoters. Here, we examine the roles of specific phosphorylation events catalysed by either protein kinase A (PKA c ) or Chk1, in regulating the functions of p50 homodimers. LC-MS/MS analysis of proteolysed p50 following in vitro phosphorylation allows us to define Ser328 and Ser337 as PKA c - and Chk1-mediated modifications, and pinpoint an additional four Chk1 phosphosites: Ser65, Thr152, Ser242 and Ser248. Native mass spectrometry (MS) reveals Chk1- and PKA c -regulated disruption of p50 homodimer formation through Ser337. Additionally, we characterise the Chk1-mediated phosphosite, Ser242, as a regulator of DNA binding, with a S242D p50 phosphomimetic exhibiting a > 10-fold reduction in DNA binding affinity. Conformational dynamics of phosphomimetic p50 variants, including S242D, are further explored using ion-mobility MS (IM-MS). Finally, comparative theoretical modelling with experimentally observed p50 conformers, in the absence and presence of DNA, reveals that the p50 homodimer undergoes conformational contraction during electrospray ionisation that is stabilised by complex formation with κB DNA. Graphical Abstract ᅟ.

Design of Novel Chemotherapeutic Agents Targeting Checkpoint Kinase 1 Using 3D-QSAR Modeling and Molecular Docking Methods.

PubMed

Balupuri, Anand; Balasubramanian, Pavithra K; Cho, Seung J

2016-01-01

Checkpoint kinase 1 (Chk1) has emerged as a potential therapeutic target for design and development of novel anticancer drugs. Herein, we have performed three-dimensional quantitative structure-activity relationship (3D-QSAR) and molecular docking analyses on a series of diazacarbazoles to design potent Chk1 inhibitors. 3D-QSAR models were developed using comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) techniques. Docking studies were performed using AutoDock. The best CoMFA and CoMSIA models exhibited cross-validated correlation coefficient (q2) values of 0.631 and 0.585, and non-cross-validated correlation coefficient (r2) values of 0.933 and 0.900, respectively. CoMFA and CoMSIA models showed reasonable external predictabilities (r2 pred) of 0.672 and 0.513, respectively. A satisfactory performance in the various internal and external validation techniques indicated the reliability and robustness of the best model. Docking studies were performed to explore the binding mode of inhibitors inside the active site of Chk1. Molecular docking revealed that hydrogen bond interactions with Lys38, Glu85 and Cys87 are essential for Chk1 inhibitory activity. The binding interaction patterns observed during docking studies were complementary to 3D-QSAR results. Information obtained from the contour map analysis was utilized to design novel potent Chk1 inhibitors. Their activities and binding affinities were predicted using the derived model and docking studies. Designed inhibitors were proposed as potential candidates for experimental synthesis.

Negative regulation of G2-M by ATR (mei-41)/Chk1(Grapes) facilitates tracheoblast growth and tracheal hypertrophy in Drosophila.

PubMed

Kizhedathu, Amrutha; Bagul, Archit V; Guha, Arjun

2018-04-16

Imaginal progenitors in Drosophila are known to arrest in G2 during larval stages and proliferate thereafter. Here we investigate the mechanism and implications of G2 arrest in progenitors of the adult thoracic tracheal epithelium (tracheoblasts). We report that tracheoblasts pause in G2 for ~48-56 h and grow in size over this period. Surprisingly, tracheoblasts arrested in G2 express drivers of G2-M like Cdc25/String (Stg). We find that mechanisms that prevent G2-M are also in place in this interval. Tracheoblasts activate Checkpoint Kinase 1/Grapes (Chk1/Grp) in an ATR/mei-41-dependent manner. Loss of ATR/Chk1 led to precocious mitotic entry ~24-32 h earlier. These divisions were apparently normal as there was no evidence of increased DNA damage or cell death. However, induction of precocious mitoses impaired growth of tracheoblasts and the tracheae they comprise. We propose that ATR/Chk1 negatively regulate G2-M in developing tracheoblasts and that G2 arrest facilitates cellular and hypertrophic organ growth. © 2018, Kizhedathu et al.

Bimodal regulation of p21waf1 protein as function of DNA damage levels

PubMed Central

Buscemi, G; Ricci, C; Zannini, L; Fontanella, E; Plevani, P; Delia, D

2014-01-01

Human p21Waf1 protein is well known for being transcriptionally induced by p53 and activating the cell cycle checkpoint arrest in response to DNA breaks. Here we report that p21Waf1 protein undergoes a bimodal regulation, being upregulated in response to low doses of DNA damage but rapidly and transiently degraded in response to high doses of DNA lesions. Responsible for this degradation is the checkpoint kinase Chk1, which phosphorylates p21Waf1 on T145 and S146 residues and induces its proteasome-dependent proteolysis. The initial p21Waf1 degradation is then counteracted by the ATM-Chk2 pathway, which promotes the p53-dependent accumulation of p21Waf1 at any dose of damage. We also found that p21Waf1 ablation favors the activation of an apoptotic program to eliminate otherwise irreparable cells. These findings support a model in which in human cells a balance between ATM-Chk2-p53 and the ATR-Chk1 pathways modulates p21Waf1 protein levels in relation to cytostatic and cytotoxic doses of DNA damage. PMID:25486478

Volatile Organic Compounds (VOCs) Measurements in Karachi, Pakistan (2006): a Comparison With Previous Urban Sampling Campaigns Worldwide.

NASA Astrophysics Data System (ADS)

Barletta, B.; Meinardi, S.; Khwaja, H. A.; Beyersdorf, A. J.; Baker, A. K.; Zou, S.; Rowland, F.; Blake, D. R.

2008-12-01

Mixing ratios of carbon monoxide (CO), carbon dioxide (CO2), methane (CH4), and 47 nonmethane hydrocarbons - NMHCs - (19 alkanes, 13 alkenes, ethyne, and 14 aromatics) were determined for ground level whole air samples collected during the winter of 2006 in Karachi, Pakistan. Pakistan is among the fastest growing economies in Asia, and Karachi is one of the largest cities in the world with a rapidly expanding population of over 14 million in the whole metropolitan area, and a large industrial base. Samples were collected in January 2006 throughout the urban area to characterize the overall air composition of the city, and along the busiest road to determine the traffic signature of Karachi. This sampling campaign follows a previous study carried out in the winter of 1998-1999 in the same city, when elevated concentrations of many NMHCs were observed. Exceptionally high levels of methane were still observed in 2006 with an average mixing ratio of 5.0 ppmv (6.3 ppmv were observed in 1999). The overall air composition of the Karachi urban environment characterized during this 2006 sampling is compared to 1999 aiming to highlight any possible change in the main VOC sources present throughout the city. In particular, we want to evaluate the impact of the heavy usage of natural gas on the overall air quality of Karachi and the recently increased use of liquefied petroleum gas (LPG) as alternative source of energy. We also compare the composition of the urban troposphere of Karachi to other major urban centers worldwide such as Guangzhou (China), Mexico City (Mexico), and Milan (Italy).

Screening for G6PD Deficiency Among Neonates with Neonatal Jaundice Admitted to Tertiary Care Center: A Need in Disguise.

PubMed

Kumar, Kishwer; Sohaila, Arjumand; Tikmani, Shiyam Sunder; Khan, Iqtidar Ahmed; Zafar, Anila

2015-08-01

This study was conducted to determine the association of Glucose-6-Phosphate Dehydrogenase (G-6-PD) deficiency among neonates admitted with jaundice at the neonatal intensive care unit, well baby nursery and neonatal step down nursery of the Aga Khan University Hospital, Karachi, Pakistan, from January to June 2010. A total of 205 neonates following the selection criteria were included. All selected neonates have their venous blood drawn, saved in EDTA bottle and sent to laboratory of The Aga Khan University Hospital (AKUH). The laboratory results of whether G-6-PD deficiency was present or not was recorded in the proforma. G-6-PD was deficient in 19 neonates (9.3%). All neonates were male.

The ATR Signaling Pathway Is Disabled during Infection with the Parvovirus Minute Virus of Mice

PubMed Central

Adeyemi, Richard O.

2014-01-01

ABSTRACT The ATR kinase has essential functions in maintenance of genome integrity in response to replication stress. ATR is recruited to RPA-coated single-stranded DNA at DNA damage sites via its interacting partner, ATRIP, which binds to the large subunit of RPA. ATR activation typically leads to activation of the Chk1 kinase among other substrates. We show here that, together with a number of other DNA repair proteins, both ATR and its associated protein, ATRIP, were recruited to viral nuclear replication compartments (autonomous parvovirus-associated replication [APAR] bodies) during replication of the single-stranded parvovirus minute virus of mice (MVM). Chk1, however, was not activated during MVM infection even though viral genomes bearing bound RPA, normally a potent trigger of ATR activation, accumulate in APAR bodies. Failure to activate Chk1 in response to MVM infection was likely due to our observation that Rad9 failed to associate with chromatin at MVM APAR bodies. Additionally, early in infection, prior to the onset of the virus-induced DNA damage response (DDR), stalling of the replication of MVM genomes with hydroxyurea (HU) resulted in Chk1 phosphorylation in a virus dose-dependent manner. However, upon establishment of full viral replication, MVM infection prevented activation of Chk1 in response to HU and various other drug treatments. Finally, ATR phosphorylation became undetectable upon MVM infection, and although virus infection induced RPA32 phosphorylation on serine 33, an ATR-associated phosphorylation site, this phosphorylation event could not be prevented by ATR depletion or inhibition. Together our results suggest that MVM infection disables the ATR signaling pathway. IMPORTANCE Upon infection, the parvovirus MVM activates a cellular DNA damage response that governs virus-induced cell cycle arrest and is required for efficient virus replication. ATM and ATR are major cellular kinases that coordinate the DNA damage response to diverse DNA damage stimuli. Although a significant amount has been discovered about ATM activation during parvovirus infection, involvement of the ATR pathway has been less studied. During MVM infection, Chk1, a major downstream target of ATR, is not detectably phosphorylated even though viral genomes bearing the bound cellular single-strand binding protein RPA, normally a potent trigger of ATR activation, accumulate in viral replication centers. ATR phosphorylation also became undetectable. In addition, upon establishment of full viral replication, MVM infection prevented activation of Chk1 in response to hydroxyurea and various other drug treatments. Our results suggest that MVM infection disables this important cellular signaling pathway. PMID:24965470

The ATR signaling pathway is disabled during infection with the parvovirus minute virus of mice.

PubMed

Adeyemi, Richard O; Pintel, David J

2014-09-01

The ATR kinase has essential functions in maintenance of genome integrity in response to replication stress. ATR is recruited to RPA-coated single-stranded DNA at DNA damage sites via its interacting partner, ATRIP, which binds to the large subunit of RPA. ATR activation typically leads to activation of the Chk1 kinase among other substrates. We show here that, together with a number of other DNA repair proteins, both ATR and its associated protein, ATRIP, were recruited to viral nuclear replication compartments (autonomous parvovirus-associated replication [APAR] bodies) during replication of the single-stranded parvovirus minute virus of mice (MVM). Chk1, however, was not activated during MVM infection even though viral genomes bearing bound RPA, normally a potent trigger of ATR activation, accumulate in APAR bodies. Failure to activate Chk1 in response to MVM infection was likely due to our observation that Rad9 failed to associate with chromatin at MVM APAR bodies. Additionally, early in infection, prior to the onset of the virus-induced DNA damage response (DDR), stalling of the replication of MVM genomes with hydroxyurea (HU) resulted in Chk1 phosphorylation in a virus dose-dependent manner. However, upon establishment of full viral replication, MVM infection prevented activation of Chk1 in response to HU and various other drug treatments. Finally, ATR phosphorylation became undetectable upon MVM infection, and although virus infection induced RPA32 phosphorylation on serine 33, an ATR-associated phosphorylation site, this phosphorylation event could not be prevented by ATR depletion or inhibition. Together our results suggest that MVM infection disables the ATR signaling pathway. Upon infection, the parvovirus MVM activates a cellular DNA damage response that governs virus-induced cell cycle arrest and is required for efficient virus replication. ATM and ATR are major cellular kinases that coordinate the DNA damage response to diverse DNA damage stimuli. Although a significant amount has been discovered about ATM activation during parvovirus infection, involvement of the ATR pathway has been less studied. During MVM infection, Chk1, a major downstream target of ATR, is not detectably phosphorylated even though viral genomes bearing the bound cellular single-strand binding protein RPA, normally a potent trigger of ATR activation, accumulate in viral replication centers. ATR phosphorylation also became undetectable. In addition, upon establishment of full viral replication, MVM infection prevented activation of Chk1 in response to hydroxyurea and various other drug treatments. Our results suggest that MVM infection disables this important cellular signaling pathway. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Cell cycle perturbation induced by gemcitabine in human tumor cells in cell culture, xenografts and bladder cancer patients: implications for clinical trial designs combining gemcitabine with a Chk1 inhibitor.

PubMed

Montano, Ryan; Khan, Nadeem; Hou, Huagang; Seigne, John; Ernstoff, Marc S; Lewis, Lionel D; Eastman, Alan

2017-09-15

Gemcitabine irreversibly inhibits ribonucleotide reductase and induces S phase arrest but whether this occurs in tumors in mice or patients has not been established. Tumor cells in culture were incubated with gemcitabine for 6 h to approximate the administration schedule in a patient. Concentrations that induced persistent S phase arrest thereafter correlated with cell killing. Administration of gemcitabine to mice also demonstrated a persistent S phase arrest in their tumor. The minimum dose that induced almost complete S phase arrest after 24 h (40 mg/kg) was well below the maximum tolerated dose in mice. S phase arrest was also observed in tumors of bladder cancer patients receiving gemcitabine. The Chk1 inhibitor MK-8776 sensitized cells to gemcitabine with the greatest cell killing when added 18 h after gemcitabine. In mice, the administration of MK-8776 18 h after gemcitabine elicited positivity for the DNA damage marker γH2AX; this also occurred at relatively low dose (40 mg/kg) gemcitabine. Hence, in both cell culture and xenografts, MK-8776 can markedly enhance cell killing of cells reversibly arrested in S phase by gemcitabine. Some cell lines are hypersensitive to MK-8776 as monotherapy, but this was not observed in xenograft models. Effective monotherapy requires a higher dose of Chk1 inhibitor, and target inhibition over a longer time period as compared to its use in combination. These results have important implications for combining Chk1 inhibitors with gemcitabine and suggest that Chk1 inhibitors with increased bioavailability may have improved efficacy both in combination and as monotherapy.

DW-MRI as a Predictive Biomarker of Radiosensitization of GBM through Targeted Inhibition of Checkpoint Kinases.

PubMed

Williams, Terence M; Galbán, Stefanie; Li, Fei; Heist, Kevin A; Galbán, Craig J; Lawrence, Theodore S; Holland, Eric C; Thomae, Tami L; Chenevert, Thomas L; Rehemtulla, Alnawaz; Ross, Brian D

2013-04-01

The inherent treatment resistance of glioblastoma (GBM) can involve multiple mechanisms including checkpoint kinase (Chk1/2)-mediated increased DNA repair capability, which can attenuate the effects of genotoxic chemotherapies and radiation. The goal of this study was to evaluate diffusion-weighted magnetic resonance imaging (DW-MRI) as a biomarker for Chk1/2 inhibitors in combination with radiation for enhancement of treatment efficacy in GBM. We evaluated a specific small molecule inhibitor of Chk1/2, AZD7762, in combination with radiation using in vitro human cell lines and in vivo using a genetically engineered GBM mouse model. DW-MRI and T1-contrast MRI were used to follow treatment effects on intracranial tumor cellularity and growth rates, respectively. AZD7762 inhibited clonal proliferation in a panel of GBM cell lines and increased radiosensitivity in p53-mutated GBM cell lines to a greater extent compared to p53 wild-type cells. In vivo efficacy of AZD7762 demonstrated a dose-dependent inhibitory effect on GBM tumor growth rate and a reduction in tumor cellularity based on DW-MRI scans along with enhancement of radiation efficacy. DW-MRI was found to be a useful imaging biomarker for the detection of radiosensitization through inhibition of checkpoint kinases. Chk1/2 inhibition resulted in antiproliferative activity, prevention of DNA damage-induced repair, and radiosensitization in preclinical GBM tumor models, both in vitro and in vivo. The effects were found to be maximal in p53-mutated GBM cells. These results provide the rationale for integration of DW-MRI in clinical translation of Chk1/2 inhibition with radiation for the treatment of GBM.

Cell cycle G2/M arrest through an S phase-dependent mechanism by HIV-1 viral protein R.

PubMed

Li, Ge; Park, Hyeon U; Liang, Dong; Zhao, Richard Y

2010-07-07

Cell cycle G2 arrest induced by HIV-1 Vpr is thought to benefit viral proliferation by providing an optimized cellular environment for viral replication and by skipping host immune responses. Even though Vpr-induced G2 arrest has been studied extensively, how Vpr triggers G2 arrest remains elusive. To examine this initiation event, we measured the Vpr effect over a single cell cycle. We found that even though Vpr stops the cell cycle at the G2/M phase, but the initiation event actually occurs in the S phase of the cell cycle. Specifically, Vpr triggers activation of Chk1 through Ser345 phosphorylation in an S phase-dependent manner. The S phase-dependent requirement of Chk1-Ser345 phosphorylation by Vpr was confirmed by siRNA gene silencing and site-directed mutagenesis. Moreover, downregulation of DNA replication licensing factors Cdt1 by siRNA significantly reduced Vpr-induced Chk1-Ser345 phosphorylation and G2 arrest. Even though hydroxyurea (HU) and ultraviolet light (UV) also induce Chk1-Ser345 phosphorylation in S phase under the same conditions, neither HU nor UV-treated cells were able to pass through S phase, whereas vpr-expressing cells completed S phase and stopped at the G2/M boundary. Furthermore, unlike HU/UV, Vpr promotes Chk1- and proteasome-mediated protein degradations of Cdc25B/C for G2 induction; in contrast, Vpr had little or no effect on Cdc25A protein degradation normally mediated by HU/UV. These data suggest that Vpr induces cell cycle G2 arrest through a unique molecular mechanism that regulates host cell cycle regulation in an S-phase dependent fashion.

Phosphorylation of Minichromosome Maintenance 3 (MCM3) by Checkpoint Kinase 1 (Chk1) Negatively Regulates DNA Replication and Checkpoint Activation.

PubMed

Han, Xiangzi; Mayca Pozo, Franklin; Wisotsky, Jacob N; Wang, Benlian; Jacobberger, James W; Zhang, Youwei

2015-05-08

Mechanisms controlling DNA replication and replication checkpoint are critical for the maintenance of genome stability and the prevention or treatment of human cancers. Checkpoint kinase 1 (Chk1) is a key effector protein kinase that regulates the DNA damage response and replication checkpoint. The heterohexameric minichromosome maintenance (MCM) complex is the core component of mammalian DNA helicase and has been implicated in replication checkpoint activation. Here we report that Chk1 phosphorylates the MCM3 subunit of the MCM complex at Ser-205 under normal growth conditions. Mutating the Ser-205 of MCM3 to Ala increased the length of DNA replication track and shortened the S phase duration, indicating that Ser-205 phosphorylation negatively controls normal DNA replication. Upon replicative stress treatment, the inhibitory phosphorylation of MCM3 at Ser-205 was reduced, and this reduction was accompanied with the generation of single strand DNA, the key platform for ataxia telangiectasia mutated and Rad3-related (ATR) activation. As a result, the replication checkpoint is activated. Together, these data provide significant insights into the regulation of both normal DNA replication and replication checkpoint activation through the novel phosphorylation of MCM3 by Chk1. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

PHD3-dependent hydroxylation of HCLK2 promotes the DNA damage response

PubMed Central

Xie, Liang; Pi, Xinchun; Mishra, Ashutosh; Fong, Guohua; Peng, Junmin; Patterson, Cam

2012-01-01

The DNA damage response (DDR) is a complex regulatory network that is critical for maintaining genome integrity. Posttranslational modifications are widely used to ensure strict spatiotemporal control of signal flow, but how the DDR responds to environmental cues, such as changes in ambient oxygen tension, remains poorly understood. We found that an essential component of the ATR/CHK1 signaling pathway, the human homolog of the Caenorhabditis elegans biological clock protein CLK-2 (HCLK2), associated with and was hydroxylated by prolyl hydroxylase domain protein 3 (PHD3). HCLK2 hydroxylation was necessary for its interaction with ATR and the subsequent activation of ATR/CHK1/p53. Inhibiting PHD3, either with the pan-hydroxylase inhibitor dimethyloxaloylglycine (DMOG) or through hypoxia, prevented activation of the ATR/CHK1/p53 pathway and decreased apoptosis induced by DNA damage. Consistent with these observations, we found that mice lacking PHD3 were resistant to the effects of ionizing radiation and had decreased thymic apoptosis, a biomarker of genomic integrity. Our identification of HCLK2 as a substrate of PHD3 reveals the mechanism through which hypoxia inhibits the DDR, suggesting hydroxylation of HCLK2 is a potential therapeutic target for regulating the ATR/CHK1/p53 pathway. PMID:22797300

Presence of rotavirus and free-living amoebae in the water supplies of Karachi, Pakistan.

PubMed

Yousuf, Farzana Abubakar; Siddiqui, Ruqaiyyah; Khan, Naveed Ahmed

2017-06-01

Rotavirus and pathogenic free-living amoebae are causative agents of important health problems, especially for developing countries like Pakistan where the population has limited access to clean water supplies. Here, we evaluated the prevalence of rotavirus and free-living amoebae (Acanthamoeba spp., Balamuthia mandrillaris, Naegleria fowleri) in drinking water supplies of Karachi, Pakistan. Six water filtration plants that supply drinking water to the population of Karachi were investigated. Additionally, drinking water samples from households were analyzed for the presence of rotavirus and free-living amoebae. Rotavirus was present in 35% of the water samples collected from water filtration plants; however, domestic tap water samples had a prevalence of only 5%. Out of 20 water samples from filtration plants, 13 (65%) were positive for Acanthamoeba spp., and one (5%) was positive for B. mandrillaris. Out of 20 drinking water samples collected from different areas of Karachi, 35% were positive for Acanthamoeba spp. Rotavirus was detected in 5% of the drinking water samples tested. Overall, these findings showed for the first time the presence of rotavirus, in addition to pathogenic free-living amoebae in drinking water supplies of Karachi that could be an important public health risk for the affected population.

Spatial patterns monitoring of road traffic injuries in Karachi metropolis.

PubMed

Lateef, Muhammad U

2011-06-01

This article aims to assess the pattern of road traffic injuries (RTIs) and fatalities in Karachi metropolis. Assessing the pattern of RTIs in Karachi at this juncture is important for many reasons. The rapid motorisation in the recent years due to the availability of credit has significantly increased the traffic volume of the city. Since then, the roads of Karachi have continuously developed at a rapid pace. This development has come with a high human loss, because the construction of multilevel flyovers, signal-free corridors and the resulting high-speed traffic ultimately increase the severity of injuries. The reasons for this high proportion are inadequate infrastructure, poor enforcement of safety regulations, high crash severity index and greater population of vulnerable road user groups (riders and pedestrians). This research is the first of its kind in the country to have a geocoded database of fatalities and injuries in a geographical information system for the entire city of Karachi. In fact, road crashes are both predictable and preventable. Developing countries should learn from the experience of highly motorised nations to avoid the high burden of RTIs by adopting road safety and prevention measures.

Simulation of rainfall-runoff for major flash flood events in Karachi

NASA Astrophysics Data System (ADS)

Zafar, Sumaira

2016-07-01

Metropolitan city Karachi has strategic importance for Pakistan. With the each passing decade the city is facing urban sprawl and rapid population growth. These rapid changes directly affecting the natural resources of city including its drainage pattern. Karachi has three major cities Malir River with the catchment area of 2252 sqkm and Lyari River has catchment area about 470.4 sqkm. These are non-perennial rivers and active only during storms. Change of natural surfaces into hard pavement causing an increase in rainfall-runoff response. Curve Number is increased which is now causing flash floods in the urban locality of Karachi. There is only one gauge installed on the upstream of the river but there no record for the discharge. Only one gauge located at the upstream is not sufficient for discharge measurements. To simulate the maximum discharge of Malir River rainfall (1985 to 2014) data were collected from Pakistan meteorological department. Major rainfall events use to simulate the rainfall runoff. Maximum rainfall-runoff response was recorded in during 1994, 2007 and 2013. This runoff causes damages and inundation in floodplain areas of Karachi. These flash flooding events not only damage the property but also cause losses of lives

Potential Drug-Drug Interactions among Patients prescriptions collected from Medicine Out-patient Setting.

PubMed

Farooqui, Riffat; Hoor, Talea; Karim, Nasim; Muneer, Mehtab

2018-01-01

To identify and evaluate the frequency, severity, mechanism and common pairs of drug-drug interactions (DDIs) in prescriptions by consultants in medicine outpatient department. This cross sectional descriptive study was done by Pharmacology department of Bahria University Medical & Dental College (BUMDC) in medicine outpatient department (OPD) of a private hospital in Karachi from December 2015 to January 2016. A total of 220 prescriptions written by consultants were collected. Medications given with patient's diagnosis were recorded. Drugs were analyzed for interactions by utilizing Medscape drug interaction checker, drugs.com checker and stockley`s drug interactions index. Two hundred eleven prescriptions were selected while remaining were excluded from the study because of unavailability of the prescribed drugs in the drug interaction checkers. In 211 prescriptions, two common diagnoses were diabetes mellitus (28.43%) and hypertension (27.96%). A total of 978 medications were given. Mean number of medications per prescription was 4.6. A total of 369 drug-drug interactions were identified in 211 prescriptions (175%). They were serious 4.33%, significant 66.12% and minor 29.53%. Pharmacokinetic and pharmacodynamic interactions were 37.94% and 51.21% respectively while 10.84% had unknown mechanism. Number wise common pairs of DDIs were Omeprazole-Losartan (S), Gabapentine- Acetaminophen (M), Losartan-Diclofenac (S). The frequency of DDIs is found to be too high in prescriptions of consultants from medicine OPD of a private hospital in Karachi. Significant drug-drug interactions were more and mostly caused by Pharmacodynamic mechanism. Number wise evaluation showed three common pairs of drugs involved in interactions.

Newborn care knowledge and practices among mothers attending pediatric outpatient clinic of a hospital in Karachi, Pakistan

PubMed Central

Gul, Saadia; Khalil, Rehana; Yousafzai, M. Tahir; Shoukat, Faiza

2014-01-01

Objectives To assess newborn care knowledge and practices among mothers. Methodology A cross-sectional study was conducted at a tertiary care hospital in Karachi, Pakistan. A total of 170 mothers accompanying their infants attending the Paediatric Out Patient Department were interviewed through a structured questionnaire. Areas of inquiry included Antenatal care seeking, delivery care, cord care, eye care, bathing and breastfeeding practices. Results Ninety-two percent mothers reported at least one antenatal care visit. Tetanus Toxoid coverage was 88%. Home deliveries were 18%. Seventy-four percent reported applying various substances like coconut oil, mustard oil, purified butter and turmeric to the cord stump. Kohl application to newborn’s eyes was 68%, while 86% reported first bath within 24 hrs of birth. 48% mothers initiated breastfeeding within 2 hours of delivery. Colostrum was discarded by 43% and prelacteal feeds given by 73%. Exclusive Breast Feeding rate was 26%. Family income of Rs. 10, 000 (USD120) or less/month and maternal education level of primary or less were significantly associated with home delivery, unhygienic cord care and kohl application to the newborn’s eyes. Home delivery was a risk factor for poor cord care (OR=4.07) and discarding colostrum (OR= 3.18). Conclusion Antenatal care coverage was good, but knowledge regarding newborn care was poor. Harmful practices regarding newborn care were prevalent among mothers. Institutional deliveries did not guarantee optimal practices. Tradition and culture played a significant role. Health education can improve the mothers’ knowledge regarding newborn care practices. PMID:25246884

Potential Drug-Drug Interactions among Patients prescriptions collected from Medicine Out-patient Setting

PubMed Central

Farooqui, Riffat; Hoor, Talea; Karim, Nasim; Muneer, Mehtab

2018-01-01

Objective: To identify and evaluate the frequency, severity, mechanism and common pairs of drug-drug interactions (DDIs) in prescriptions by consultants in medicine outpatient department. Methods: This cross sectional descriptive study was done by Pharmacology department of Bahria University Medical & Dental College (BUMDC) in medicine outpatient department (OPD) of a private hospital in Karachi from December 2015 to January 2016. A total of 220 prescriptions written by consultants were collected. Medications given with patient's diagnosis were recorded. Drugs were analyzed for interactions by utilizing Medscape drug interaction checker, drugs.com checker and stockley`s drug interactions index. Two hundred eleven prescriptions were selected while remaining were excluded from the study because of unavailability of the prescribed drugs in the drug interaction checkers. Results: In 211 prescriptions, two common diagnoses were diabetes mellitus (28.43%) and hypertension (27.96%). A total of 978 medications were given. Mean number of medications per prescription was 4.6. A total of 369 drug-drug interactions were identified in 211 prescriptions (175%). They were serious 4.33%, significant 66.12% and minor 29.53%. Pharmacokinetic and pharmacodynamic interactions were 37.94% and 51.21% respectively while 10.84% had unknown mechanism. Number wise common pairs of DDIs were Omeprazole-Losartan (S), Gabapentine- Acetaminophen (M), Losartan-Diclofenac (S). Conclusion: The frequency of DDIs is found to be too high in prescriptions of consultants from medicine OPD of a private hospital in Karachi. Significant drug-drug interactions were more and mostly caused by Pharmacodynamic mechanism. Number wise evaluation showed three common pairs of drugs involved in interactions. PMID:29643896

Reduced susceptibility to chlorhexidine disinfectant among New Delhi metallo-beta-lactamase-1 positive Enterobacteriaceae and other multidrug-resistant organisms: Report from a tertiary care hospital in Karachi, Pakistan.

PubMed

Mal, P B; Farooqi, J; Irfan, S; Hughes, M A; Khan, E

2016-01-01

We analysed susceptibility of multidrug-resistant organisms (MDROs) including New Delhi metallo-beta-lactamase-1 positive Enterobacteriaceae to chlorhexidine and compared results to their susceptible counterparts. Susceptibilities of chlorhexidine digluconate in a standard (CHX-S) preparation and two commercial disinfectants containing different CHX concentrations (2% w/v and 4% w/w) were performed. MDROs had narrower range of higher CHX-S minimum inhibitory concentrations (MICs) as compared to pan-sensitive organisms. The MIC values for commercial disinfectants products for MDROs were many folds higher (20-600 times), than CHX-S for in vitro use. Increasing antibiotic resistance among bacterial isolates can be an indirect marker of reduced susceptibility to chlorhexidine in hospital setting.

Chk1 and Cds1: linchpins of the DNA damage and replication checkpoint pathways

PubMed Central

Rhind, Nicholas; Russell, Paul

2010-01-01

SUMMARY Recent work on the mechanisms of DNA damage and replication cell cycle checkpoints has revealed great similarity between the checkpoint pathways of organisms as diverse as yeasts, flies and humans. However, there are differences in the ways these organisms regulate their cell cycles. To connect the conserved checkpoint pathways with various cell cycle targets requires an adaptable link that can target different cell cycle components in different organisms. The Chk1 and Cds1 protein kinases, downstream effectors in the checkpoint pathways, seem to play just such roles. Perhaps more surprisingly, the two kinases not only have different targets in different organisms but also seem to respond to different signals in different organisms. So, whereas in fission yeast Chk1 is required for the DNA damage checkpoint and Cds1 is specifically involved in the replication checkpoint, their roles seem to be shuffled in metazoans. PMID:11058076

Prevalence and pattern of self-medication in Karachi: A community survey

PubMed Central

Afridi, M. Iqbal; Rasool, Ghulam; Tabassum, Rabia; Shaheen, Marriam; Siddiqullah; Shujauddin, M.

2015-01-01

Objective: To study the prevalence and pattern of self-medication among adult males and females in Karachi, Pakistan. Methods: This cross-sectional community- based survey was carried out at five randomly selected towns of Karachi (Defence, Gulshan-e-Iqbal, North Nazimabad, Malir, Orangi town) over a period of 3 months (October, November & December 2012). A sample size of 500 adult cases (250 males & 250 females), with systemic random selection from different towns of Karachi were inducted in this study. The city was divided in 5 zones and one town from each zone was selected by systemic randomization. First available male and female from each randomly selected house were included in the study. After consent and confidentiality assurance they were interviewed on semi-structured Performa designed for this purpose. Results were analyzed and tabulated through SPSS v14.0. Result: The prevalence of self-medication in males and females in Karachi is found to be 84.8% (males 88.4% and females 81.2%). The most frequent symptoms for which self-medication used were headache (32.7%), fever (23.3%) and the medicines used were painkillers (28.8%), fever reducer medicines (19.8%). The most common reason 33.3% was previous experience with similar symptom. Conclusion: Self-medication is highly prevalent (84.8%) in Karachi. It was frequently used for headache followed by fever. Predominantly painkillers, fever reducer and cough syrups were used in the form of tablets and syrups. Main source of medicines for males were friends and for females were relatives. PMID:26649022

“Post partum hemorrhage: causes and management”

PubMed Central

2013-01-01

Background Post partum hemorrhage is defined as blood loss of 500 ml or above. It is the most common cause of pre-mature mortality of women world wide. Our objective was to evaluate the most common etiology and method of management of Post partum Hemorrhage in a tertiary care hospital of Karachi. Findings It was a cross sectional study conducted at Liaquat National Hospital Karachi, during the period of July 2011 to May 2012. Review include mode of delivery, possible cause of postpartum hemorrhage, supportive, medical and surgical interventions. All the women admitted with post partum hemorrhage or develop PPH in hospital after delivery were included in our study. Bleeding disorder and use of anticoagulants were set as exclusion criteria. Diagnosis was made on the basis of blood loss assessment which was made via subjective and objective evaluation. During the targeted months, out of total 1493 deliveries (26/1493 = 1.741%) 26 cases of post partum hemorrhage were reported with a mean age of 26.153 ± 7.37. No deaths were reported and all cases were referred and unbooked cases. All Patients were conscious, tachycardiac and hypotensive. Most of the women were suffering from hemorrhage during or after the birth of their 1st child. Primary post partum hemorrhage emerge as the most common type of post partum hemorrhage and uterine atony was detected as the most common cause of primary post partum hemorrhage. Retained products of conception was the most common cause of secondary post partum hemorrhage and hysterectomy was found to be the most frequent method of management of post partum hemorrhage. Conclusion This study highlights the existing variable practices for the management of postpartum hemorrhage. Hemorrhage associated morbidity and mortality can be prevented by critical judgment, early referral and resuscitation by attendants. Introduction of an evidence-based management model can potentially reduce the practice variability and improve the quality of care. PMID:23773785

Presence of rotavirus and free-living amoebae in the water supplies of Karachi, Pakistan

PubMed Central

Yousuf, Farzana Abubakar; Siddiqui, Ruqaiyyah; Khan, Naveed Ahmed

2017-01-01

ABSTRACT Rotavirus and pathogenic free-living amoebae are causative agents of important health problems, especially for developing countries like Pakistan where the population has limited access to clean water supplies. Here, we evaluated the prevalence of rotavirus and free-living amoebae (Acanthamoeba spp., Balamuthia mandrillaris, Naegleria fowleri) in drinking water supplies of Karachi, Pakistan. Six water filtration plants that supply drinking water to the population of Karachi were investigated. Additionally, drinking water samples from households were analyzed for the presence of rotavirus and free-living amoebae. Rotavirus was present in 35% of the water samples collected from water filtration plants; however, domestic tap water samples had a prevalence of only 5%. Out of 20 water samples from filtration plants, 13 (65%) were positive for Acanthamoeba spp., and one (5%) was positive for B. mandrillaris. Out of 20 drinking water samples collected from different areas of Karachi, 35% were positive for Acanthamoeba spp. Rotavirus was detected in 5% of the drinking water samples tested. Overall, these findings showed for the first time the presence of rotavirus, in addition to pathogenic free-living amoebae in drinking water supplies of Karachi that could be an important public health risk for the affected population. PMID:28591260

An Evaluation of Systematic Tuberculosis Screening at Private Facilities in Karachi, Pakistan

PubMed Central

Creswell, Jacob; Khowaja, Saira; Codlin, Andrew; Hashmi, Rabia; Rasheed, Erum; Khan, Mubashir; Durab, Irfan; Mergenthaler, Christina; Hussain, Owais; Khan, Faisal; Khan, Aamir J.

2014-01-01

Background In Pakistan, like many Asian countries, a large proportion of healthcare is provided through the private sector. We evaluated a systematic screening strategy to identify people with tuberculosis in private facilities in Karachi and assessed the approaches' ability to diagnose patients earlier in their disease progression. Methods and Findings Lay workers at 89 private clinics and a large hospital outpatient department screened all attendees for tuberculosis using a mobile phone-based questionnaire during one year. The number needed to screen to detect a case of tuberculosis was calculated. To evaluate early diagnosis, we tested for differences in cough duration and smear grading by screening facility. 529,447 people were screened, 1,010 smear-positive tuberculosis cases were detected and 942 (93.3%) started treatment, representing 58.7% of all smear-positive cases notified in the intervention area. The number needed to screen to detect a smear-positive case was 124 (prevalence 806/100,000) at the hospital and 763 (prevalence 131/100,000) at the clinics; however, ten times the number of individuals were screened in clinics. People with smear-positive TB detected at the hospital were less likely to report cough lasting 2–3 weeks (RR 0.66 95%CI [0.49–0.90]) and more likely to report cough duration >3 weeks (RR 1.10 95%CI [1.03–1.18]). Smear-positive cases at the clinics were less likely to have a +3 grade (RR 0.76 95%CI [0.63–0.92]) and more likely to have +1 smear grade (RR 1.24 95%CI [1.02–1.51]). Conclusions Tuberculosis screening at private facilities is acceptable and can yield large numbers of previously undiagnosed cases. Screening at general practitioner clinics may find cases earlier than at hospitals although more people must be screened to identify a case of tuberculosis. Limitations include lack of culture testing, therefore underestimating true TB prevalence. Using more sensitive and specific screening and diagnostic tests such as chest x-ray and Xpert MTB/RIF may improve results. PMID:24705600

An evaluation of systematic tuberculosis screening at private facilities in Karachi, Pakistan.

PubMed

Creswell, Jacob; Khowaja, Saira; Codlin, Andrew; Hashmi, Rabia; Rasheed, Erum; Khan, Mubashir; Durab, Irfan; Mergenthaler, Christina; Hussain, Owais; Khan, Faisal; Khan, Aamir J

2014-01-01

In Pakistan, like many Asian countries, a large proportion of healthcare is provided through the private sector. We evaluated a systematic screening strategy to identify people with tuberculosis in private facilities in Karachi and assessed the approaches' ability to diagnose patients earlier in their disease progression. Lay workers at 89 private clinics and a large hospital outpatient department screened all attendees for tuberculosis using a mobile phone-based questionnaire during one year. The number needed to screen to detect a case of tuberculosis was calculated. To evaluate early diagnosis, we tested for differences in cough duration and smear grading by screening facility. 529,447 people were screened, 1,010 smear-positive tuberculosis cases were detected and 942 (93.3%) started treatment, representing 58.7% of all smear-positive cases notified in the intervention area. The number needed to screen to detect a smear-positive case was 124 (prevalence 806/100,000) at the hospital and 763 (prevalence 131/100,000) at the clinics; however, ten times the number of individuals were screened in clinics. People with smear-positive TB detected at the hospital were less likely to report cough lasting 2-3 weeks (RR 0.66 95%CI [0.49-0.90]) and more likely to report cough duration >3 weeks (RR 1.10 95%CI [1.03-1.18]). Smear-positive cases at the clinics were less likely to have a +3 grade (RR 0.76 95%CI [0.63-0.92]) and more likely to have +1 smear grade (RR 1.24 95%CI [1.02-1.51]). Tuberculosis screening at private facilities is acceptable and can yield large numbers of previously undiagnosed cases. Screening at general practitioner clinics may find cases earlier than at hospitals although more people must be screened to identify a case of tuberculosis. Limitations include lack of culture testing, therefore underestimating true TB prevalence. Using more sensitive and specific screening and diagnostic tests such as chest x-ray and Xpert MTB/RIF may improve results.

Sodium valproate, a histone deacetylase inhibitor, enhances the efficacy of vinorelbine-cisplatin-based chemoradiation in non-small cell lung cancer cells.

PubMed

Gavrilov, Vladimir; Lavrenkov, Konstantin; Ariad, Samuel; Shany, Shraga

2014-11-01

To enhance the anticancer activity of vinorelbine, cisplatin and ionizing radiation (IR) combination against non-small cell lung cancer (NSCLC) cells by co-administration of sodium valproate (VPA), a histone deacetylase inhibitor, and to elucidate molecular events underpinning treatment efficacy. The NSCLC A549 cell line was treated with cisplatin (0.2 μg/ml), vinorelbine (2 nM), VPA (1 mM) and IR (2.5 Gy) alone, or in combination. Cell proliferation, cell-cycle distribution, apoptosis, and levels of DNA double-strand breaks, activated DNA damage checkpoint kinases pCHK1, pCHK2, cell-cycle inhibitors p21CIP1/WAF1 and p27KIP1 were assessed. VPA markedly enhanced the DNA-damaging effect of the cisplatin-vinorelbine-IR combination and induced increased DSBs, and expression of pCHK2, pCHK1, p21CIP1/WAF1 and p27KIP1. These molecular changes led to cell-cycle arrest and increased apoptosis and consequently markedly curtailed cancer cell growth. VPA markedly enhances the anticancer activity of cisplatin-vinorelbine-IR combination. This finding has translational implications for enhancing the efficacy of anticancer treatment and for reducing side-effects by reducing doses of radiation and drugs. Copyright© 2014 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Pathogenesis of New Strains of Newcastle Disease Virus From Israel and Pakistan.

PubMed

Pandarangga, P; Brown, C C; Miller, P J; Haddas, R; Rehmani, S F; Afonso, C L; Susta, L

2016-07-01

In the past few years, Newcastle disease virus (NDV) strains with epizootic characteristics belonging to subgenotypes VIIi and XIIIb emerged in the Middle East and Asia. In this study, 2 NDV strains-1 representative of subgenotype VIIi isolated in Israel (Kvuzat/13) and 1 representative of subgenotype XIIIb isolated in Pakistan (Karachi/07)-were characterized by intracerebral pathogenicity index and detailed clinicopathologic assessment. The intracerebral pathogenicity index values for Kvuzat/13 and Karachi/07 were 1.89 and 1.85, respectively, classifying these strains as virulent by international standards. In 4-week-old White Leghorn chickens, both strains caused 100% mortality within 4 (Kvuzat/13) and 5 (Karachi/07) days postinfection. Histopathology and immunohistochemistry for NDV nucleoprotein showed that both strains had wide systemic distribution, especially targeting lymphoid organs and mucosa-associated lymphoid tissues in the respiratory and intestinal tracts. Results of the animal experiment confirm that both Kvuzat/13 and Karachi/07 are highly virulent and behaved as velogenic viscerotropic NDV strains. © The Author(s) 2016.

Heavy Metals Contamination in Coastal Sediments of Karachi, Pakistan

NASA Astrophysics Data System (ADS)

Siddique, A.; Mumtaz, M.; Zaigham, N. A.; Mallick, K. A.; Saied, S.; Khwaja, H. A.

2008-12-01

Toxic compounds such as heavy metals exert chronic and lethal effects in animals, plants, and human health. With the rapid industrialization, urbanization, and economic development in Karachi, heavy metals are continuing to be introduced to estuarine and coastal environment through rivers, runoff and land-based point sources. Pollution in the Karachi coastal region (167 km long) is mainly attributed to Lyari and Malir Rivers flowing through the city of Karachi. Both rivers are served by various channels of domestic and industrial wastes carrying more than 300 million gallons per day untreated effluent of 6000 industries and ultimately drain into the beaches of Arabian Sea. Concentrations of selected heavy metals (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) in surface sediments from eighty-eight sites in Karachi coastal region were studied in order to understand metal contamination due to industrialization, urbanization, and economic development in Karachi. Sediment samples were collected in 2005 and 2006. We have found that heavy metal concentrations in surface sediments varied from 0.006 to 24.3 ug/g for Cd, 5.1 to 95 ug/g for Co, 2.9 to 571 ug/g for Cr, 6.9 to 272 ug/g for Cu, 0.55 to 6.5% for Fe, 1.2 to 318 ug/g for Mn, 7.5 to 75 ug/g for Ni, 6.3 to 121 ug/g for Pb, and 3.3 to 389 ug/g for Zn. Enrichment factors (EFs) were calculated to assess whether the concentrations observed represent background or contaminated levels. The highest levels of metals were found to be at the confluence of the Lyari and Malir River streams at the Arabian Sea, indicating the impact of the effluents of the highly urbanized and industrialized city of Karachi. Furthermore, this study assessed heavy metal toxicity risk with the application of Sediment Quality Guideline (SQG) indices (effect range low/effect range median values, ERL/ERM). Results indicated that the potential toxicity of marine environment can cause adverse biological effects to the biota directly and the human health indirectly through food web chain.

Psychosocial experiences of women with vesicovaginal fistula: a qualitative approach.

PubMed

Farid, Farah Naz; Azhar, Maimoona; Samnani, Sunil Sadruddin; Allana, Saleema; Naz, Angeela; Bohar, Farzana; Shamim; Syed, Shershah

2013-11-01

Vesicovaginal fistula (VVF) is a condition associated with a number of physical and psychological consequences. In order to gain a deeper understanding of the issues faced by women diagnosed with VVF, a qualitative exploratory study was carried out to explore the experiences of women suffering from VVF. The study included 8 women hospitalized with the diagnosis of vesicovaginal fistula at Kohi Goth Women's Hospital, Karachi, Pakistan. Semi structured interviews of each participant were conducted, recorded, and transcribed. Five major themes were identified, among which all of the participants experienced physical discomforts, psychological disturbances, issues with social and interpersonal relationships and financial constraints. However, concerns with religious practices were experienced by 87.5% of the participants. Pakistani women who are suffering through VVF face many challenges. Combined efforts should be made to offer supportive services to women suffering from this condition.

Frequency of color blindness in pre-employment screening in a tertiary health care center in Pakistan.

PubMed

Chhipa, Shaukat Ali; Hashmi, Farzeen K; Ali, Shehreen; Kamal, Mustafa; Ahmad, Khabir

2017-01-01

To describe the frequency of color vision deficiency among Pakistani adults presenting for pre-employment health screening in a tertiary care hospital. The cross-sectional study was carried out at the Aga Khan University Hospital, Karachi, and the data was collected for color vision deficiency, age, gender, and job applied for from pre-employment examination during 2013-2014. IBM SPSS 20 was used for statistical analysis. Three thousand four hundred and thirty seven persons underwent pre-employment screening during 2013 and 2014; 1837 (53.44%) were males and 1600 (46.65%) females. The mean age was 29.01 (±6.53) years. A total of 0.9% (32/3437) persons had color vision deficiency with male being 1.4% and female 0.4%. Color vision deficiency was observed in 0.9% of candidates screened for pre-employment health check up in a tertiary care hospital. The color vision deficiency was predominantly present in male individuals.

Comparison between Greulich-Pyle and Girdany-Golden methods for estimating skeletal age of children in Pakistan.

PubMed

Awais, Muhammad; Nadeem, Naila; Husen, Yousuf; Rehman, Abdul; Beg, Madiha; Khattak, Yasir Jamil

2014-12-01

To compare Greulich-Pyle (GP) and Girdany-Golden (GG) methods for estimation of Skeletal Age (SA) in children referred to a tertiary care hospital in Karachi, Pakistan. Cross-sectional study. Department of Radiology, The Aga Khan University Hospital, Karachi, Pakistan, from July 2010 to June 2012. Children up to the age of 18 years, who had undergone X-ray for the evaluation of trauma were included. Each X-ray was interpreted using both methods by two consultant paediatric radiologists having at least 10 years experience, who were blinded to the actual Chronologic Age (CA) of children. A total of 283 children were included. No significant difference was noted in mean SA estimated by GP method and mean CA for female children (p=0.695). However, a significant difference was noted between mean CA and mean SA by GG method for females (p=0.011). For males, there was a significant difference between mean CA and mean SA estimated by both GP and GG methods. A stronger correlation was found between CA and SA estimated by GP method (r=0.943 for girls, r=0.915 for boys) as compared to GG method (r=0.909 for girls, r=0.865 for boys) respectively. Bland- Altman analysis also revealed that the two methods cannot be used interchangeably. Excellent correlation was seen between the two readers for both GP and GG methods. There was no additional benefit of using GP and GG methods simultaneously over using GP method alone. Moreover, although GP was reliable in estimating SA in girls, it was unable to accurately assess SA in boys. Therefore, it would be ideal to develop indigenous standards of bone age estimation based on a representative sample of healthy native children.

Knowledge, attitude and practice regarding obesity among patients, at Aga Khan University Hospital, Karachi.

PubMed

Qidwai, Waris; Azam, Syed Iqbal

2004-01-01

Obesity is a major public health problem and responsible for significant morbidity and mortality among our patients. It is important to study the knowledge, attitude and practices with regard to obesity among patients, in order to devise interventional strategies. Patients visiting the out-patient clinics of Aga Khan University Hospital, Karachi, were included in the study. The interview was questionnaire-based and recorded the demographic profile of the patients and questions relevant to the objective of the study. The ethical requirements for the study were met. SPSS computer software was used for data management. A hundred patients were surveyed. Women (55%) were more than men (45%), under 39 years (73%), married (55%), with graduate or more education (65%), in private service (44%) and housewives (19%). A substantial number of respondents (75%) understood the meaning of obesity and considered it a major health problem (90%). More respondents felt the need to reduce weight (52%), despite the fact that lesser number considered themselves to be overweight or obese (34%). A majority of the respondents did exercise (59%) but a minority did it more than five times a week (17%) and more than 30 minutes on each occasion (31%). A substantial proportion of the respondents stated their preference for oily food (34%), sweets (34%), fried food (40%), red meat (21%), fast food (37%), butter, cheese and cream (31%). We have found a significant level of understanding about obesity among our patients. Physical exercise and dietary measures to control body weight are lacking despite the desire to have appropriate body weight. There is a need and we strongly recommend patient education programs to control obesity.

Attitude and practice of patients and doctors towards complementary and alternative medicine.

PubMed

Junaid, Rabyyan; Abaas, Mustafa; Fatima, Batool; Anis, Irma; Hussain, Mehwish

2012-08-01

To determine the attitude towards complementary and alternative medicine among the doctors and patients. The study was carried out at Civil Hospital Karachi and Liaquat National University Hospital, Karachi during April to September 2010. Two sets of questionnaires were developed separately for doctors and patients. Each set consisted of queries regarding demographic data of patients and doctors. The questionnaire for the patients contained questions reflecting the general attitude, mode of complimentary and alternative medicine usage, disease referred and the underlined reasons behind pricking the options. The questionnaires for doctors in general laid focus on the personal opinion about the practice not only for their own use, but also related to their concern towards those patients who used complimentary and alternative medicine. Predictive analysis software statistics 18 was used for statistical analysis. Of the patients, 237 (59.3%) used complimentary and alternative medicine. Herbal medicine followed by homeopathic medicine were the most commonly used therapies. Fever and cough were the most common diseases for which patients used the options. The preference was mainly based on inter-personal communications, reliance on complimentary and alternative medicine, and financial restriction. Concealing from the doctors was common in patients. Only 62 (34.4%) out of 180 doctors used complimentary and alternative medicine themselves. Refusal by other doctors was because they considered the option ineffective, obsolete and unsatisfactory. About half of the doctors forbade the patients to use such therapies, but 31% (n=73) patients ignored the doctor's advice. The use of complimentary and alternative medicine is highly prevalent in our society by patients irrespective of their social class. Preference for such therapies, on the other hand, is quite low among medical doctors as they consider allopathic medicine to be effective.

Case Series of Naegleria fowleri Primary Ameobic Meningoencephalitis from Karachi, Pakistan.

PubMed

Ghanchi, Najia K; Jamil, Bushra; Khan, Erum; Ansar, Zeeshan; Samreen, Azra; Zafar, Afia; Hasan, Zahra

2017-11-01

Naegleria fowleri causes primary amoebic meningoencephalitis (PAM) which is almost always fatal. Naegleria fowleri is waterborne, and its infections are usually associated with aquatic activities but it can also be transmitted via the domestic water supply. An increasing number of N. fowleri cases have been reported from Pakistan. Improved methods for diagnosis are required. We report the utility of polymerase chain reaction (PCR) for the diagnosis of N. fowleri in patients suspected of PAM. One hundred and sixteen cases suspected of having PAM were examined. Cerebrospinal fluid (CSF) specimens were tested at the Aga Khan University Hospital, Karachi. Nineteen CSF specimens were positive for N. fowleri using PCR. Naegleria fowleri positive patients had a median age of 28 years and were 84% male and 16% female. Overall, CSF wet preparation microscopy was performed in 85 (73%) cases and identified that seven specimens were positive for motile trophozoites. The CSF wet preparation results were available for 15 of the 19 N. fowleri PCR positive CSF samples; seven (40%) wet preparations were positive. Our data highlight the threat of N. fowleri infection as a cause of PAM. It also emphasizes the utility of the PCR-based diagnosis of the amoeba for early diagnosis and management of the disease.

Frequency, pattern and management of acute abdomen in dengue fever in Karachi, Pakistan.

PubMed

Shamim, Muhammad

2010-07-01

This study aimed to determine the frequency, pattern and management of acute abdomen in patients with dengue fever. This descriptive case series is a prospective analysis of acute abdomen in dengue fever that was performed at three secondary care hospitals in Karachi, Pakistan from June 1, 2005 to December 31, 2008. The inclusion criterion was all patients with confirmed diagnosis of dengue fever. Patients with incomplete laboratory, ultrasound or histopathology data were excluded. Among 357 patients with dengue fever, 43 (12.04%) had acute abdomen. There were 15 men and 28 women, with a median age of 29 years. These included 26 cases of acute cholecystitis, 7 cases of acute appendicitis, 7 cases of nonspecific peritonitis, and 3 cases of acute pancreatitis. Dengue hemorrhagic fever/shock syndrome was found in acute pancreatitis, and two of these patients died. Emergency surgery was required in eight patients (5 appendectomy and 3 open cholecystectomy). Substantial transfusion of blood and its components was required in eight patients who underwent emergency surgery. Early diagnosis and prompt conservative management of dengue acute abdomen is necessary to avoid mortality and emergency surgery-related morbidity. However, if needed, surgery can be performed with acceptable morbidity. Copyright © 2010 Asian Surgical Association. Published by Elsevier B.V. All rights reserved.

Novel Design Strategy for Checkpoint Kinase 2 Inhibitors Using Pharmacophore Modeling, Combinatorial Fusion, and Virtual Screening

PubMed Central

Wang, Yen-Ling

2014-01-01

Checkpoint kinase 2 (Chk2) has a great effect on DNA-damage and plays an important role in response to DNA double-strand breaks and related lesions. In this study, we will concentrate on Chk2 and the purpose is to find the potential inhibitors by the pharmacophore hypotheses (PhModels), combinatorial fusion, and virtual screening techniques. Applying combinatorial fusion into PhModels and virtual screening techniques is a novel design strategy for drug design. We used combinatorial fusion to analyze the prediction results and then obtained the best correlation coefficient of the testing set (r test) with the value 0.816 by combining the BesttrainBesttest and FasttrainFasttest prediction results. The potential inhibitors were selected from NCI database by screening according to BesttrainBesttest + FasttrainFasttest prediction results and molecular docking with CDOCKER docking program. Finally, the selected compounds have high interaction energy between a ligand and a receptor. Through these approaches, 23 potential inhibitors for Chk2 are retrieved for further study. PMID:24864236

77 FR 29755 - Additional Designations, Foreign Narcotics Kingpin Designation Act

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-18

..., Fisherman Colony Mahim, Mumbai, India; House No. C-201, Extension-A, Karachi Development Scheme, Karachi, Pakistan; DOB 24 Nov 1960; POB Mumbai (Bombay), India; nationality India; Passport AA762402 (Pakistan); alt... Manzil, 78 Temkar Street, Nagpada, Mumbai, India; DOB 31 Dec 1955; alt. DOB 1960; POB Mumbai (Bombay...

Regiospecific Synthesis of Ring A Fused Withaferin A Isoxazoline Analogues: Induction of Premature Senescence by W-2b in Proliferating Cancer Cells.

PubMed

Rasool, Faheem; Nayak, Debasis; Katoch, Archana; Faheem, Mir Mohd; Yousuf, Syed Khalid; Hussain, Nazar; Belawal, Chetan; Satti, N K; Goswami, Anindya; Mukherjee, Debaraj

2017-10-23

Induction of premature senescence represents a novel functional strategy to curb the uncontrolled proliferation of malignant cancer cells. This study unveils the regiospecific synthesis of novel isoxazoline derivatives condensed to ring A of medicinal plant product Withaferin-A. Intriguingly, the cis fused products with β-oriented hydrogen exhibited excellent cytotoxic activities against proliferating human breast cancer MCF7 and colorectal cancer HCT-116 cells. The most potent derivative W-2b triggered premature senescence along with increase in senescence-associated β-galactosidase activity, G2/M cell cycle arrest, and induction of senescence-specific marker p21 Waf1/Cip1 at its sub-toxic concentration. W-2b conferred a robust increase in phosphorylation of mammalian checkpoint kinase-2 (Chk2) in cancer cells in a dose-dependent manner. Silencing of endogenous Chk2 by siRNA divulged that the amplification of p21 expression and senescence by W-2b was Chk2-dependent. Chk2 activation (either by ectopic overexpression or through treatment with W-2b) suppressed NM23-H1 signaling axis involved in cancer cell proliferation. Finally, W-2b showed excellent in vivo efficacy with 83.8% inhibition of tumor growth at a dose of 25 mg/kg, b.w. in mouse mammary carcinoma model. Our study claims that W-2b could be a potential candidate to limit aberrant cellular proliferation rendering promising improvement in the treatment regime in cancer patients.

Inhibition of CHK1 sensitizes Ewing sarcoma cells to the ribonucleotide reductase inhibitor gemcitabine

PubMed Central

Goss, Kelli L; Koppenhafer, Stacia L; Harmoney, Kathryn M; Terry, William W; Gordon, David J

2017-01-01

Ewing sarcoma is a bone and soft tissue sarcoma that occurs in children and young adults. The EWS-FLI1 gene fusion is the driver mutation in most Ewing sarcoma tumors and functions, in part, as an aberrant transcription factor. We recently identified that Ewing sarcoma cells are sensitive to inhibition of ribonucleotide reductase (RNR), which catalyzes the formation of deoxyribonucleotides from ribonucleotides. In this report, we show that Ewing sarcoma cells are sensitive to treatment with clofarabine, which is a nucleoside analogue and allosteric inhibitor of RNR. However, clofarabine is a reversible inhibitor of RNR and we found that the effect of clofarabine is limited when using a short (6-hour) drug treatment. Gemcitabine, on the other hand, is an irreversible inhibitor of the RRM1 subunit of RNR and this drug induces apoptosis in Ewing sarcoma cells when used in both 6-hour and longer drug treatments. Treatment of Ewing sarcoma cells with gemcitabine also results in activation of checkpoint kinase 1 (CHK1), which is a critical mediator of cell survival in the setting of impaired DNA replication. Notably, inhibition of CHK1 function in Ewing sarcoma cells using a small-molecule CHK1 inhibitor, or siRNA knockdown, in combination with gemcitabine results in increased toxicity both in vitro and in vivo in a mouse xenograft experiment. Overall, our results provide insight into Ewing sarcoma biology and identify a candidate therapeutic target, and drug combination, in Ewing sarcoma. PMID:29152060

Anthocyanins from roselle extract arrest cell cycle G2/M phase transition via ATM/Chk pathway in p53-deficient leukemia HL-60 cells.

PubMed

Tsai, Tsung-Chang; Huang, Hui-Pei; Chang, Kai-Ting; Wang, Chau-Jong; Chang, Yun-Ching

2017-04-01

Cell cycle regulation is an important issue in cancer therapy. Delphinidin and cyanidin are two major anthocyanins of the roselle plant (Hibiscus sabdariffa). In the present study, we investigated the effect of Hibiscus anthocyanins (HAs) on cell cycle arrest in human leukemia cell line HL-60 and the analyzed the underlying molecular mechanisms. HAs extracted from roselle calyces (purity 90%) markedly induced G2/M arrest evaluated with flow cytometry analysis. Western blot analyses revealed that HAs (0.1-0.7 mg mL -1 ) induced G2/M arrest via increasing Tyr15 phosphorylation of Cdc2, and inducing Cdk inhibitors p27 and p21. HAs also induced phosphorylation of upstream signals related to G2/M arrest such as phosphorylation of Cdc25C tyrosine phosphatase at Ser216, increasing the binding of pCdc25C with 14-3-3 protein. HAs-induced phosphorylation of Cdc25C could be activated by ATM checkpoint kinases, Chk1, and Chk2. We first time confirmed that ATM-Chk1/2-Cdc25C pathway as a critical mechanism for G2/M arrest in HAs-induced leukemia cell cycle arrest, indicating that this compound could be a promising anticancer candidate or chemopreventive agents for further investigation. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1290-1304, 2017. © 2016 Wiley Periodicals, Inc.

Dietary modification, body mass index (BMI), blood pressure (BP) and cardiovascular risk in medical students of a government medical college of Karachi.

PubMed

Raza, Sajjad; Sheikh, Muhammad Adil; Hussain, Muhammad Fawwad Ahmed; Siddiqui, Saad Ebrahim; Muhammad, Rabia; Aziz, Sina; Qamar, Salima; Saleem, Mohammad Azfar; Waki, Nida; Faruqi, Hina; Zia, Aisha

2010-11-01

To determine the prevalence of major risk factors including dietary modification, Body Mass Index (BMI), Blood Pressure (BP) and physical activity in medical students of government teaching hospitals of Karachi. A cross sectional study was conducted on students of Dow Medical College, Karachi, Pakistan through a structured pre-tested questionnaire. Non-probability purposive sampling was used. Smoking, hypertension, family history of cardiovascular disease (CVD), overweight and low physical activity levels are risk factors the presence of which can lead to development of CVD. Prevalence of these risk factors was determined by asking appropriate questions and through measurement of BMI and blood pressure for overweight and hypertension respectively. Awareness of risk factors was determined through knowledge of the effect of various food substances on development of CVD and of adoption of dietary changes keeping in mind the risk of developing CVD. SPSS 16.0 was used for statistical analysis. A total of 132 medical students were included in the study of which 57 (43.2%) and 75 (56.8%) were male and female respectively with mean age of 20.85 +/- 1.21 years. About 15.9% of students had elevated blood pressure i.e. > or = 140/90 mmHg. Twenty eight percent of the total students were found to be underweight and 17.4% were overweight, 5% had some history of CVD, 56.8% had family history of CVD, 9.4% were smokers and 29.5% had high physical activity level. About 87.1% had modified their diet for preventing CVD. Most of the students had adequate knowledge about the cardiovascular risk factors Majority of students were not overweight. A high prevalence of cardiovascular risk factors; family history and elevated blood pressure was present. Awareness in terms of knowledge was satisfactory but implementation in terms of diet modification and adequate physical activity was lacking.

Integrated Electronic Warfare System Advanced Development Model (ADM); Appendix 1 - Functional Requirement Specification.

DTIC Science & Technology

1977-10-01

APPROVED DATE FUNCTION APPROVED jDATE WRITER J . K-olanek 2/6/76 REVISIONS CHK DESCRIPTION REV CHK DESCRIPTION IREV REVISION jJ ~ ~ ~~~ _ II SHEET NO...DOCUMENT (CDBDD) 45 5.5 COMPUTER PROGRAM PACKAGE (CPP)- j 45 5.6 COMPUTER PROGRAM OPERATOR’S MANUAL (CPOM) 45 5.7 COMPUTER PROGRAM TEST PLAN (CPTPL) 45...I LIST OF FIGURES Number Page 1 JEWS Simplified Block Diagram 4 2 System Controller Architecture 5 SIZE CODE IDENT NO DRAWING NO. A 49956 SCALE REV J

Menstrual Knowledge and Practices of Female Adolescents in Urban Karachi, Pakistan

ERIC Educational Resources Information Center

Ali, Tazeen Saeed; Rizvi, Syeda Naghma

2010-01-01

Menstruation is a normal physiological process that is managed differently according to various social and cultural understandings. Therefore, this cross-sectional study was conducted to explore the menstrual practices among 1275 female adolescents of urban Karachi, Pakistan from April to October 2006 by using interviews. Data was entered and…

CTC Sentinel. Volume 6, Issue 5, May 2013

DTIC Science & Technology

2013-05-01

25, 2013. 9 Farrukh Saleem , “Why Karachi is Bleeding,” The News International, October 21, 2010. can find sanctuaries in Pashtun neighborhoods.10 A...suggest that of the 20 million people living in Karachi, roughly one million live in neighborhoods where the TTP has chi,” Dawn, April 26, 2013; Imran

Nutritional status and physical abuse among the children involved in domestic labour in Karachi Pakistan: a cross-sectional survey.

PubMed

Zainab, Saima; Kadir, Masood

2016-10-01

To determine the prevalence of physical abuse among domestic child labours and to assess the nutritional status by calculating the Body Mass Index of children involved in domestic labour in Karachi. A cross sectional study was conducted in the squatter settlements of Karachi. Questionnaire based interviews were conducted to capture physical abuse with 385 children who worked as domestic labour in the household of their employer. The ages of the children were between 10 to 14 years belonging to both genders. The children were enrolled in study by snow-ball sampling technique. The overall prevalence of physical abuse among domestic child labour in Karachi was found to be 8.3 %. Over 9 % had low weight and about 90% were stunted. This study also highlighted that 95% of the children involved in domestic labour perform overtime work in their employer's home, more than once per week. There is high burden of physical abuse among the domestic child labour and these children are malnourished. There is a need to recognize and regulate this form of labour in Pakistan.

Frequency of tetanus toxoid immunization among college/university female students of Karachi.

PubMed

Qadir, Murad; Murad, Rafat; Mumtaz, Seema; Azmi, Abdul Azim; Rehman, Rehana; Omm-E-Hani; Aziz, Nasir

2010-01-01

Tetanus is a deadly infectious disease for which immunisation is available in EPI at both infant level and for females of reproductive age. More than 95% of patients who develop tetanus have not been previously immunised. Objectives of the study were to determine the frequency of tetanus vaccination and to access the awareness of immunisation among females studying in 11 girls' colleges of Karachi and University of Karachi. A cross sectional study was conducted among 1,407 females studying in colleges and University of Karachi from April to August 2007 using a prescribed questionnaire. Among 1,407 female students who were interviewed for the study, 232 (16.48%) were not aware about tetanus immunisation program for females of reproductive age. Only 560 students (39.80%) received at least 1 of 5 recommended doses. Only 41 female students (2.91%) received complete course of 5 doses. Coverage of tetanus immunisation among literate females in most populous city of the country is far behind satisfactory. There is need for awareness and crash programs of tetanus immunisation.

The constant threat of terrorism: stress levels and coping strategies amongst university students of Karachi.

PubMed

Ahmed, Ayesha Ejaz; Masood, Komal; Dean, Sohni Vicky; Shakir, Tanzila; Kardar, Ahmed Abdul Hafeez; Barlass, Usman; Imam, Syed Haider; Mohmand, Mohammad Ghawar Khan; Ibrahim, Hussain; Khan, Imad Saeed; Akram, Usman; Hasnain, Farid

2011-04-01

To assess the levels of stress in the face of terrorism and the adopted coping strategies, amongst the student population of universities in Karachi. A descriptive, cross sectional study was conducted on undergraduate students from four universities of Karachi. Self-administered questionnaires were filled out by 291 students. Pearson Chi-Square test was used to assess associations between stress levels and different variables at a level of significance of 0.05%. A total of 65.8% of the students had mild stress levels, 91.5% of university students were exposed to terrorism through television, while only 26.5% students reported personal exposure to terrorism. 67.4% students were forbidden by their parents to go out (p = 0.002). Most of those who had self exposure to an attack were the ones whose parents forbade them from going out (p = 0.00). Most commonly used coping strategy was increased faith in religion. Irritability was the most common stress symptom. A majority of students studying in universities of Karachi had mild stress levels due to the constant threat of terrorism whereas a minority had severe stress levels. Possible reasons for resilience and only mild stress levels could be the history of Karachi's internal conflicts and its prolonged duration of being exposed to terrorism. These students who are positive for stress need to be targeted for counseling either through the media or through their universities. More extensive research is needed in this area.

Factors associated with elevated blood lead concentrations in children in Karachi, Pakistan.

PubMed Central

Rahbar, Mohammad Hossein; White, Franklin; Agboatwalla, Mubina; Hozhabri, Siroos; Luby, Stephen

2002-01-01

OBJECTIVES: To confirm whether blood lead concentrations in Karachi were as high as reported in 1989 and to identify which types of exposure to lead contribute most to elevated blood lead concentrations in children in Karachi. METHODS: A total of 430 children aged 36-60 months were selected through a geographically stratified design from the city centre, two suburbs, a rural community and an island situated within the harbour at Karachi. Blood samples were collected from children and a pretested questionnaire was administered to assess the effect of various types of exposure. Cooked food, drinking-water and house dust samples were collected from households. FINDINGS: About 80% of children had blood lead concentrations 10 g/dl, with an overall mean of 15.6 g/dl. At the 5% level of significance, houses nearer to the main intersection in the city centre, application of surma to children's eyes, father's exposure to lead at workplace, parents' illiteracy and child's habit of hand- to-mouth activity were among variables associated with elevated lead concentrations in blood. CONCLUSION: These findings are of public health concern, as most children in Karachi are likely to suffer some degree of intellectual impairment as a result of environmental lead exposure. We believe that there is enough evidence of the continuing problem of lead in petrol to prompt the petroleum industry to take action. The evidence also shows the need for appropriate interventions in reducing the burden due to other factors associated with this toxic element. PMID:12471396

Acute porphyrias: clinical spectrum of hospitalized patients.

PubMed

Sheerani, Mughis; Urfy, Mian Zainulsajadeen; Hassan, Ali; Islam, Zunaira; Baig, Shahid

2007-11-01

To determine characteristics, clinical features and triggers of acute porphyria in hospitalized patients presenting to a tertiary care center in Pakistan. Case series. The Aga Khan University Hospital, Karachi, from 1988 to 2003. Case records of 26 patients hospitalized with diagnosis were identified through computerized hospital patients' data. The diagnosis of acute porphyria was based on pertinent clinical features and laboratory investigations after exclusion of other alternative diagnosis and patients previously diagnosed as porphyric. The data was analyzed through SPSS software version 11.0. Twelve patients (46.2%) were males. Mean age was 21 years. Most common manifestation were gastrointestinal (n=22; 88.5%) followed by neurological symptoms (n=14; 54%). Neurological manifestations included seizures (n=9; 34.6%) and neuropathy (n=6; 23%). One patient presented with depression and insomnia. Family history was positive in (n=8; 30.8%). Eighteen (69%) had history of previous attacks at their presentation to the hospital. Most common precipitating factor was 'eating outside' (n=18; 69%). Porphyrias are uncommon and cryptic group of diseases. This study shows a slightly different gender distribution, earlier onset of symptoms, higher number of neuropsychiatric symptoms (especially seizures), more distal neuropathies and different precipitant in the studied subset of patients than described previously in the western studies.

A multi-criteria decision-making approach to rank supplier selection criteria for hospital waste management: A case from Pakistan.

PubMed

Ishtiaq, Palvisha; Khan, Sharfuddin Ahmed; Haq, Moiz-Ul

2018-04-01

To address environmental issues and cost effectiveness, waste management is necessary for healthcare facilities. Most importantly, segregation of hazardous and non-hazardous waste must be done as in many developing countries; disposal of both types of healthcare waste is done together, which is an unsafe practice. Waste generated in hospitals needs proper management to minimise hazards for patient and healthcare workers. At the same time, it is quite difficult for hospitals to find a systematic way to select appropriate suppliers for hospital waste management. Therefore, the purpose of this article is to identify, validate, and rank criteria that are essential for hospital waste management suppliers' selection. The analytical hierarchal process approach has been used and a survey from Pakistan's largest city (Karachi) has been considered to rank the most appropriate criteria that is necessary to select the supplier, especially in a developing country like Pakistan. Results show that waste management cost (45.5%) and suppliers' details (31.5%) are the top two main criteria for supplier selection; and storage cost (15.7%), waste handling cost (14.7%), and qualification of the suppliers (10.9%) are the top three most important overall sub-criteria for supplier selection for hospital waste management.

The effect of ATM kinase inhibition on the initial response of human dental pulp and periodontal ligament mesenchymal stem cells to ionizing radiation.

PubMed

Cmielova, Jana; Havelek, Radim; Kohlerova, Renata; Soukup, Tomas; Bruckova, Lenka; Suchanek, Jakub; Vavrova, Jirina; Mokry, Jaroslav; Rezacova, Martina

2013-07-01

This study evaluates early changes in human mesenchymal stem cells (MSC) isolated from dental pulp and periodontal ligament after γ-irradiation and the effect of ataxia-telangiectasia mutated (ATM) inhibition. MSC were irradiated with 2 and 20 Gy by (60)Co. For ATM inhibition, specific inhibitor KU55933 was used. DNA damage was measured by Comet assay and γH2AX detection. Cell cycle distribution and proteins responding to DNA damage were analyzed 2-72 h after the irradiation. The irradiation of MSC causes an increase in γH2AX; the phosphorylation was ATM-dependent. Irradiation activates ATM kinase, and the level of p53 protein is increased due to its phosphorylation on serine15. While this phosphorylation of p53 is ATM-dependent in MSC, the increase in p53 was not prevented by ATM inhibition. A similar trend was observed for Chk1 and Chk2. The increase in p21 is greater without ATM inhibition. ATM inhibition also does not fully abrogate the accumulation of irradiated MSC in the G2-phase of the cell-cycle. In irradiated MSC, double-strand breaks are tagged quickly by γH2AX in an ATM-dependent manner. Although phosphorylations of p53(ser15), Chk1(ser345) and Chk2(thr68) are ATM-dependent, the overall amount of these proteins increases when ATM is inhibited. In both types of MSC, ATM-independent mechanisms for cell-cycle arrest in the G2-phase are triggered.

Low expression levels of ATM may substitute for CHEK2 /TP53 mutations predicting resistance towards anthracycline and mitomycin chemotherapy in breast cancer.

PubMed

Knappskog, Stian; Chrisanthar, Ranjan; Løkkevik, Erik; Anker, Gun; Østenstad, Bjørn; Lundgren, Steinar; Risberg, Terje; Mjaaland, Ingvil; Leirvaag, Beryl; Miletic, Hrvoje; Lønning, Per E

2012-03-15

Mutations affecting p53 or its upstream activator Chk2 are associated with resistance to DNA-damaging chemotherapy in breast cancer. ATM (Ataxia Telangiectasia Mutated protein) is the key activator of p53 and Chk2 in response to genotoxic stress. Here, we sought to evaluate ATM's potential role in resistance to chemotherapy. We sequenced ATM and assessed gene expression levels in pre-treatment biopsies from 71 locally advanced breast cancers treated in the neoadjuvant setting with doxorubicin monotherapy or mitomycin combined with 5-fluorouracil. Findings were confirmed in a separate patient cohort treated with epirubicin monotherapy. Each tumor was previously analyzed for CHEK2 and TP53 mutation status. While ATM mutations were not associated with chemo-resistance, low ATM expression levels predicted chemo-resistance among patients with tumors wild-type for TP53 and CHEK2 (P = 0.028). Analyzing the ATM-chk2-p53 cascade, low ATM levels (defined as the lower 5 to 50% percentiles) or mutations inactivating TP53 or CHEK2 robustly predicted anthracycline resistance (P-values varying between 0.001 and 0.027 depending on the percentile used to define "low" ATM levels). These results were confirmed in an independent cohort of 109 patients treated with epirubicin monotherapy. In contrast, ATM-levels were not suppressed in resistant tumors harboring TP53 or CHEK2 mutations (P > 0.5). Our data indicate loss of function of the ATM-Chk2-p53 cascade to be strongly associated with resistance to anthracycline/mitomycin-containing chemotherapy in breast cancer.

Primary Amebic Meningoencephalitis Caused by Naegleria fowleri, Karachi, Pakistan

PubMed Central

Shakoor, Sadia; Beg, Mohammad Asim; Bandea, Rebecca; Sriram, Rama; Noman, Fatima; Ali, Farheen; Visvesvara, Govinda S.; Zafar, Afia

2011-01-01

We report 13 cases of Naegleria fowleri primary amebic meningoencephalitis in persons in Karachi, Pakistan, who had no history of aquatic activities. Infection likely occurred through ablution with tap water. An increase in primary amebic meningoencephalitis cases may be attributed to rising temperatures, reduced levels of chlorine in potable water, or deteriorating water distribution systems. PMID:21291600

hMSH5 Facilitates the Repair of Camptothecin-induced Double-strand Breaks through an Interaction with FANCJ*

PubMed Central

Xu, Yang; Wu, Xiling; Her, Chengtao

2015-01-01

Replication stress from stalled or collapsed replication forks is a major challenge to genomic integrity. The anticancer agent camptothecin (CPT) is a DNA topoisomerase I inhibitor that causes fork collapse and double-strand breaks amid DNA replication. Here we report that hMSH5 promotes cell survival in response to CPT-induced DNA damage. Cells deficient in hMSH5 show elevated CPT-induced γ-H2AX and RPA2 foci with concomitant reduction of Rad51 foci, indicative of impaired homologous recombination. In addition, CPT-treated hMSH5-deficient cells exhibit aberrant activation of Chk1 and Chk2 kinases and therefore abnormal cell cycle progression. Furthermore, the hMSH5-FANCJ chromatin recruitment underlies the effects of hMSH5 on homologous recombination and Chk1 activation. Intriguingly, FANCJ depletion desensitizes hMSH5-deficient cells to CPT-elicited cell killing. Collectively, our data point to the existence of a functional interplay between hMSH5 and FANCJ in double-strand break repair induced by replication stress. PMID:26055704

Human cytomegalovirus inhibits a DNA damage response by mislocalizing checkpoint proteins

NASA Astrophysics Data System (ADS)

Gaspar, Miguel; Shenk, Thomas

2006-02-01

The DNA damage checkpoint pathway responds to DNA damage and induces a cell cycle arrest to allow time for DNA repair. Several viruses are known to activate or modulate this cellular response. Here we show that the ataxia-telangiectasia mutated checkpoint pathway, which responds to double-strand breaks in DNA, is activated in response to human cytomegalovirus DNA replication. However, this activation does not propagate through the pathway; it is blocked at the level of the effector kinase, checkpoint kinase 2 (Chk2). Late after infection, several checkpoint proteins, including ataxia-telangiectasia mutated and Chk2, are mislocalized to a cytoplasmic virus assembly zone, where they are colocalized with virion structural proteins. This colocalization was confirmed by immunoprecipitation of virion proteins with an antibody that recognizes Chk2. Virus replication was resistant to ionizing radiation, which causes double-strand breaks in DNA. We propose that human CMV DNA replication activates the checkpoint response to DNA double-strand breaks, and the virus responds by altering the localization of checkpoint proteins to the cytoplasm and thereby inhibiting the signaling pathway. ionizing radiation | ataxia-telangiectasia mutated pathway

HPV31 Utilizes the ATR-Chk1 Pathway to Maintain Elevated RRM2 Levels and a Replication-Competent Environment in Differentiating Keratinocytes

PubMed Central

Anacker, Daniel C.; Aloor, Heather L.; Shepard, Caitlin N.; Lenzi, Gina M.; Johnson, Bryan A.; Kim, Baek; Moody, Cary A.

2016-01-01

Productive replication of human papillomaviruses (HPV) is restricted to the uppermost layers of the differentiating epithelia. How HPV ensures an adequate supply of cellular substrates for viral DNA synthesis in a differentiating environment is unclear. Here, we demonstrate that HPV31 positive cells exhibit increased dNTP pools and levels of RRM2, a component of the ribonucleotide reductase (RNR) complex, which is required for de novo synthesis of dNTPs. RRM2 depletion blocks productive replication, suggesting RRM2 provides dNTPs for viral DNA synthesis in differentiating cells. We demonstrate that HPV31 regulates RRM2 levels through expression of E7 and activation of the ATR-Chk1-E2F1 DNA damage response, which is essential to combat replication stress upon entry into S-phase, as well as for productive replication. Our findings suggest a novel way in which viral DNA synthesis is regulated through activation of ATR and Chk1 and highlight an intriguing new virus/host interaction utilized for viral replication. PMID:27764728

Novel design strategy for checkpoint kinase 2 inhibitors using pharmacophore modeling, combinatorial fusion, and virtual screening.

PubMed

Lin, Chun-Yuan; Wang, Yen-Ling

2014-01-01

Checkpoint kinase 2 (Chk2) has a great effect on DNA-damage and plays an important role in response to DNA double-strand breaks and related lesions. In this study, we will concentrate on Chk2 and the purpose is to find the potential inhibitors by the pharmacophore hypotheses (PhModels), combinatorial fusion, and virtual screening techniques. Applying combinatorial fusion into PhModels and virtual screening techniques is a novel design strategy for drug design. We used combinatorial fusion to analyze the prediction results and then obtained the best correlation coefficient of the testing set (r test) with the value 0.816 by combining the Best(train)Best(test) and Fast(train)Fast(test) prediction results. The potential inhibitors were selected from NCI database by screening according to Best(train)Best(test) + Fast(train)Fast(test) prediction results and molecular docking with CDOCKER docking program. Finally, the selected compounds have high interaction energy between a ligand and a receptor. Through these approaches, 23 potential inhibitors for Chk2 are retrieved for further study.

Role of replication protein A as sensor in activation of the S-phase checkpoint in Xenopus egg extracts

PubMed Central

Recolin, Bénédicte; Van Der Laan, Siem; Maiorano, Domenico

2012-01-01

Uncoupling between DNA polymerases and helicase activities at replication forks, induced by diverse DNA lesions or replication inhibitors, generate long stretches of primed single-stranded DNA that is implicated in activation of the S-phase checkpoint. It is currently unclear whether nucleation of the essential replication factor RPA onto this substrate stimulates the ATR-dependent checkpoint response independently of its role in DNA synthesis. Using Xenopus egg extracts to investigate the role of RPA recruitment at uncoupled forks in checkpoint activation we have surprisingly found that in conditions in which DNA synthesis occurs, RPA accumulation at forks stalled by either replication stress or UV irradiation is dispensable for Chk1 phosphorylation. In contrast, when both replication fork uncoupling and RPA hyperloading are suppressed, Chk1 phosphorylation is inhibited. Moreover, we show that extracts containing reduced levels of RPA accumulate ssDNA and induce spontaneous, caffeine-sensitive, Chk1 phosphorylation in S-phase. These results strongly suggest that disturbance of enzymatic activities of replication forks, rather than RPA hyperloading at stalled forks, is a critical determinant of ATR activation. PMID:22187152

Differential Processing of Low and High LET Radiation Induced DNA Damage: Investigation of Switch from ATM to ATR Signaling

NASA Technical Reports Server (NTRS)

Saha, Janapriya; Wang, Minli; Hada, Megumi; Cucinotta, Francis A.

2011-01-01

The members of the phosphatidylinositol kinase-like kinase family of proteins namely ataxia-telangiectasia mutated (ATM) and ATM- and Rad3-related (ATR) are directly responsible for the maintenance of genomic integrity by mounting DDR through signaling and facilitating the recruitment of repair factors at the sites of DNA damage along with coordinating the deployment of cell cycle checkpoints to permit repair by phosphorylating Checkpoint kinase Chk1, Chk2 and p53. High LET radiation from GCR (Galactic Cosmic Rays) consisting mainly of protons and high energy and charged (HZE) particles from SPE (Solar Particle Event) pose a major health risk for astronauts on their space flight missions. The determination of these risks and the design of potential safeguards require sound knowledge of the biological consequences of lesion induction and the capability of the cells to counter them. We here strive to determine the coordination of ATM and ATR kinases at the break sites directly affecting checkpoint signaling and DNA repair and whether differential processing of breaks induced by low and high LET radiation leads to possible augmentation of swap of these damage sensors at the sites of DNA damage. Exposure of cells to IR triggers rapid autophosphorylation of serine-1981 that causes dimer dissociation and initiates monomer formation of ATM. ATM kinase activity depends on the disruption of the dimer, which allows access and phosphorylation of downstream ATM substrates like Chk2. Evidence suggests that ATM is activated by the alterations in higher-order chromatin structure although direct binding of ATM to DSB ends may be a crucial step in its activation. On the other hand, in case of ATR, RPA (replication protein A)-coated ssDNA (single-stranded DNA) generated as a result of stalled DNA replication or during processing of chromosomal lesions is crucial for the localization of ATR to sites of DNA damage in association with ATR-interacting protein (ATRIP). Although the majority of RPA-coated ssDNA is generally present only during DNA replication, ATR activation in G1 and G2-phase might still require formation of RPA-coated ssDNA, probably initiated by the MRN-CtIP complex and then extended by the Exo1- or BLM-dependent mechanisms at the sites of DSBs. Evidence accumulates that activation of ATM and ATR are oppositely regulated by the length of single stranded overhangs generated at the break sites by processes mentioned above and these stretches of single stranded overhangs hold the clue for ATM to ATR switch at broken DNA ends. We irradiated 82-6hTERT human fibroblast cells with low LET gamma-rays and high LET Fe and Si particles. Preliminary results with cells exposed to 1Gy gamma-rays show that the kinetics of pChk2-pT68 foci formation is comparable to that of gamma-H2AX although they appear to recede quicker. The number and intensity of observed foci reaches a maximum at 30 min and 60 min post IR for Chk2-pT68 and gamma-H2AX foci respectively and all Chk2-pT68 foci colocalize with gamma-H2AX foci. The kinetics of Chk1-pS345 and ATRIP are being determined. Results of Chk2-pT68 foci kinetics was also corroborated by western blot experiments, although phosphorylation was detected as early as 10 min and started receding 30 min post IR with 2Gy of gamma-rays. On the other hand, level of ATR-pS428 reached its maximum between 60 and 120 min and was maintained until the last measured time point of 4 hours post IR as determined by western blotting. Experiments performed with high LET Fe and Si particles will be reported.

Physicians reading and writing practices: a cross-sectional study from Civil Hospital, Karachi, Pakistan

PubMed Central

2012-01-01

Background To determine the behavior of physicians regarding medical literature reading and participation in research activities at one of the largest teaching hospitals in Pakistan. Method This descriptive, cross-sectional study was conducted by interviewing the house officers, residents and fellows of six major specialties (Medicine, Surgery, Pediatrics, Psychology, Obstetrics & Gynecology and Anesthesia) in Civil Hospital, Karachi between August and December, 2011. The questionnaire elicited responses regarding the reading habits of physicians, preferred sources of information, their participation in research activities (publication & supervision) and views regarding journal club. SPSS 17.0 was used for data entry and analysis. Result A total of 259 completely filled questionnaires were returned with a response rate of 85.19%. Mean age of the participants was 29.67 ± 7.65 years. Books were selected by 71.4% doctors as their preferred source of information, regardless of their clinical specialties. (p < 0.05). E-journals were preferred by 75.7% of the doctors over printed journals. This holds true for doctors from all specialties (p < 0.05). The ease of searching for relevant articles was the major contributor (50.5%) in preference of e-journals. 137 (52.9%) doctors read 5 or less articles per week. 30 (11.6%) doctors have subscription of journals (printed or electronic). At least one research paper has been published by 151 (58.3%) of the physicians interviewed. Most common reason for not participating in research activities was busy schedule (56.4%). Almost half (49.4%) doctors reported lack of journal club in their units. Of these, majority (88.35%) wanted a journal club in their respective units. Conclusion Urgent intervention is required to promote healthcare literature reading and writing practice in our physicians. Easy access to workplace computers with internet and subscription of paid journals will facilitate physicians. Lack of supervisors and busy schedule were reported to be important contributors for not participating in research. Addressing these issues will encourage doctors to participate more in research activities. PMID:22840218

Diabetes related knowledge among residents and nurses: a multicenter study in Karachi, Pakistan.

PubMed

Ahmed, Asma; Jabbar, Abdul; Zuberi, Lubna; Islam, Muhammad; Shamim, Khusro

2012-09-11

Assessment of knowledge among resident trainees and nurses is very important since majority of patients admitted in hospital have underlying diabetes which could lead to adverse clinical outcomes if not managed efficiently. Therefore, the purpose of this study was to evaluate and compare the knowledge related to the management of diabetes among registered nurses (RN) and trainee residents of internal medicine (IMR), family medicine (FMR) and surgery (SR) at tertiary care hospitals of Karachi, Pakistan. A validated questionnaire consisting of 21 open ended questions related to diabetes awareness was acquired through a study done at Thomas Jefferson University Hospital, Philadelphia with the permission of primary author. 169 IMR, 27 FMR, 86 SR and 99 RN completed a questionnaire that assessed the knowledge related to different aspects of management of diabetes. The results were further stratified by participant's specialty and level of training. The percentage of knowledge based questions answered correctly was found to be low. The overall mean correct percentage among all the participants was 50% +/- 21. There was no statistical difference in terms of knowledge between IMR & FMR residents (64% +/- 14 vs. 60% +/- 16, p = 0.47) respectively. The total scores of SR and RN were quite low (40% +/- 16 & 31% +/- 15 respectively).SR and RN were found to have profound deficit in both inpatient and outpatient knowledge of diabetes. We did not observe any improvement in level of knowledge of FMR & SR with increase in duration of their training (p = 0.47 & 0.80 respectively). In contrast, improvement in the level of knowledge of IMR was observed from first to second year of their training (p = 0.03) with no further improvement thereafter. RN's didn't respond correctly on most of the items related to in-patient management of diabetes (Mean score 40% +/- 20). As there are no prior studies in our setting evaluating knowledge related to diabetes management among residents and nurses, this study is of paramount importance. Based on these results, considerable knowledge gaps were found among trainee residents and nurses pointing towards need of providing additional education to improve the delivery of diabetes care.

Harnessing Photovoice for tuberculosis advocacy in Karachi, Pakistan.

PubMed

Mohammed, Shama; Sajun, Sana Zehra; Khan, Faisal S

2015-06-01

In Pakistan, despite publically available free testing and treatment throughout the country, there were an estimated 58,000 deaths due to tuberculosis in 2010. Understanding the experiences of people affected by TB is essential in addressing barriers to effective treatment. The Indus Hospital used Photovoice to understand the experiences of people affected by TB in Karachi. Two hundred and thirty photographs and stories were collected from 55 people affected by TB. Five major themes and 12 sub-themes emerged from the data: the physical aspects of TB (weakness and the side effects of the medication), the social aspects of TB (loneliness, stigma, and the fear/guilt of infecting family members), the socio-economic aspects of TB (financial difficulties/poverty and poor living conditions), supportive factors during treatment (support from family and friends, support from welfare organizations, prayer, visiting peaceful places), and recovery (happiness about getting better). The photographs, stories, and a Call for Action were shared at a Gallery event with patients, practitioners, and policy-makers. This study provides a look at the complexities surrounding TB and emphasizes the need for holistic interventions for TB that address all aspects of the disease, including its social determinants. It also highlights the potential of Photovoice as an effective means to bring much-needed attention to this disease. © The Author (2013). Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Impact of Self-Regulation Skills on Academic Performance of Young Children in Private Schools of Karachi

ERIC Educational Resources Information Center

Kathawala, Abeer; Bhamani, Shelina

2015-01-01

This research aimed to explore if self-regulation skills had any effect on the academic outcomes of young children in private schools of Karachi, Pakistan. Quantitative research method was used to determine the impact of self-regulation upon the academic outcome of young children by utilizing Early School Self-Regulation Scale-Care Giver Version…

Perceptions of Teachers towards Assessment Techniques at Secondary Level Private School of Karachi

ERIC Educational Resources Information Center

Fatemah, Henna

2015-01-01

This paper sets out to explore the perceptions of teachers towards assessment techniques at a secondary level private school of Karachi. This was conjectured on the basis of the circumstances of parallel boards in the education system of Pakistan and its effectiveness within the context with respect to the curriculum. This was gauged in line with…

Knowledge and Attitude of General Practitioners regarding Autism in Karachi, Pakistan

ERIC Educational Resources Information Center

Rahbar, Mohammad Hossein; Ibrahim, Khalid; Assassi, Parisa

2011-01-01

General practitioners (GPs) could have an important role in early diagnosis of autism. There have been no studies evaluating the knowledge of GPs regarding autism in Pakistan. We aimed to fill that gap by assessing knowledge and attitude of GPs in Karachi regarding autism. We conducted a cross-sectional survey of 348 GPs; only 148 (44.6%) had…

The ringing bells: perspective of Karachiites regarding noise pollution.

PubMed

Ali, Liaquat; Zehra, Tabassum

2014-12-01

To identify the awareness regarding noise pollution and its adverse effects on human health in the people of urban areas of Karachi. Cross-sectional survey. Urban areas of Karachi, from September to October 2012. A survey was conducted with 50 selected subjects of urban areas of Karachi with their informed consent. The questionnaire covered aspects of noise pollution. Descriptive analysis was done with percent responses. All (100%, n=50) subjects admitted to be suffering from noise pollution. The source of noise pollution was vehicles in 64% (n=32). There was 90% (n=45) agreement for laws and regulations regarding noise pollution to be in place. Awareness sessions need to be conducted for the public regarding the effects of noise pollution on health with formulation of laws and regulations.

Fatal primary meningoencephalitis caused by Naegleria fowleri.

PubMed

Shariq, Ali; Afridi, Faisal Iqbal; Farooqi, Badar Jahan; Ahmed, Sumaira; Hussain, Arif

2014-07-01

Naegleria fowleri is a free living parasite which habitats in fresh water reservoirs. It causes a fatal nervous system infection known as primary amoebic meningoencephalitis by invading through cribriform plate of nose and gaining entry into brain. We report a case of primary amoebic meningoencephalitis caused by Naegleria fowleri in Karachi, Pakistan, in a 42 years old male poultry farm worker having no history of swimming. Clinical course was fulminant and death occurred within one week of hospital admission. Naegleria fowleri was detected by wet mount technique in the sample of cerebrospinal fluid collected by lumbar puncture of patient. This is a serious problem and requires immediate steps to prevent general population to get affected by this lethal neurological infection.

Part II. Initial molecular and cellular characterization of high nitric oxide-adapted human tongue squamous cell carcinoma cell lines.

PubMed

Tarjan, Gabor; Haines, G Kenneth; Vesper, Benjamin J; Xue, Jiaping; Altman, Michael B; Yarmolyuk, Yaroslav R; Khurram, Huma; Elseth, Kim M; Roeske, John C; Aydogan, Bulent; Radosevich, James A

2011-02-01

It is not understood why some head and neck squamous cell carcinomas, despite having identical morphology, demonstrate different tumor aggressiveness, including radioresistance. High levels of the free radical nitric oxide (NO) and increased expression of the NO-producing enzyme nitric oxide synthase (NOS) have been implicated in tumor progression. We previously adapted three human tongue cancer cell lines to high NO (HNO) levels by gradually exposing them to increasing concentrations of an NO donor; the HNO cells grew faster than their corresponding untreated ("parent") cells, despite being morphologically identical. Herein we initially characterize the HNO cells and compare the biological properties of the HNO and parent cells. HNO/parent cell line pairs were analyzed for cell cycle distribution, DNA damage, X-ray and ultraviolet radiation response, and expression of key cellular enzymes, including NOS, p53, glutathione S-transferase-pi (GST-pi), apurinic/apyrimidinic endonuclease-1 (APE1), and checkpoint kinases (Chk1, Chk2). While some of these properties were cell line-specific, the HNO cells typically exhibited properties associated with a more aggressive behavior profile than the parent cells (greater S-phase percentage, radioresistance, and elevated expression of GST-pi/APE1/Chk1/Chk2). To correlate these findings with conditions in primary tumors, we examined the NOS, GST-pi, and APE1 expression in human tongue squamous cell carcinomas. A majority of the clinical samples exhibited elevated expression levels of these enzymes. Together, the results herein suggest cancer cells exposed to HNO levels can develop resistance to free radicals by upregulating protective mechanisms, such as GST-pi and APE1. These upregulated defense mechanisms may contribute to their aggressive expression profile.

Cytotoxic Effects of Temozolomide and Radiation are Additive- and Schedule-Dependent

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chalmers, Anthony J., E-mail: a.j.chalmers@sussex.ac.u; Genome Damage and Stability Centre, University of Sussex, Falmer; Ruff, Elliot M.

2009-12-01

Purpose: Despite aggressive therapy comprising radical radiation and temozolomide (TMZ) chemotherapy, the prognosis for patients with glioblastoma multiforme (GBM) remains poor, particularly if tumors express O{sup 6}-methylguanine-DNA-methyltransferase (MGMT). The interactions between radiation and TMZ remain unclear and have important implications for scheduling and for developing strategies to improve outcomes. Methods and Materials: Factors determining the effects of combination therapy on clonogenic survival, cell-cycle checkpoint signaling and DNA repair were investigated in four human glioma cell lines (T98G, U373-MG, UVW, U87-MG). Results: Combining TMZ and radiation yielded additive cytotoxicity, but only when TMZ was delivered 72 h before radiation. Radiosensitization wasmore » not observed. TMZ induced G2/M cell-cycle arrest at 48-72 h, coincident with phosphorylation of Chk1 and Chk2. Additive G2/M arrest and Chk1/Chk2 phosphorylation was only observed when TMZ preceded radiation by 72 h. The ataxia-telangiectasia mutated (ATM) inhibitor KU-55933 increased radiation sensitivity and delayed repair of radiation-induced DNA breaks, but did not influence TMZ effects. The multiple kinase inhibitor caffeine enhanced the cytotoxicity of chemoradiation and exacerbated DNA damage. Conclusions: TMZ is not a radiosensitizing agent but yields additive cytotoxicity in combination with radiation. Our data indicate that TMZ treatment should commence at least 3 days before radiation to achieve maximum benefit. Activation of G2/M checkpoint signaling by TMZ and radiation has a cytoprotective effect that can be overcome by dual inhibition of ATM and ATR. More specific inhibition of checkpoint signaling will be required to increase treatment efficacy without exacerbating toxicity.« less

NSC30049 inhibits Chk1 pathway in 5-FU-resistant CRC bulk and stem cell populations.

PubMed

Narayan, Satya; Jaiswal, Aruna S; Sharma, Ritika; Nawab, Akbar; Duckworth, Lizette Vila; Law, Brian K; Zajac-Kaye, Maria; George, Thomas J; Sharma, Jay; Sharma, Arun K; Hromas, Robert A

2017-08-22

The 5-fluorouracil (5-FU) treatment induces DNA damage and stalling of DNA replication forks. These stalled replication forks then collapse to form one sided double-strand breaks, leading to apoptosis. However, colorectal cancer (CRC) stem cells rapidly repair the stalled/collapsed replication forks and overcome treatment effects. Recent evidence suggests a critical role of checkpoint kinase 1 (Chk1) in preventing the replicative stress. Therefore, Chk1 kinase has been a target for developing mono or combination therapeutic agents. In the present study, we have identified a novel orphan molecule NSC30049 (NSC49L) that is effective alone, and in combination potentiates 5-FU-mediated growth inhibition of CRC heterogeneous bulk and FOLFOX-resistant cell lines in culture with minimal effect on normal colonic epithelial cells. It also inhibits the sphere forming activity of CRC stem cells, and decreases the expression levels of mRNAs of CRC stem cell marker genes. Results showed that NSC49L induces 5-FU-mediated S-phase cell cycle arrest due to increased load of DNA damage and increased γ-H2AX staining as a mechanism of cytotoxicity. The pharmacokinetic analysis showed a higher bioavailability of this compound, however, with a short plasma half-life. The drug is highly tolerated by animals with no pathological aberrations. Furthermore, NSC49L showed very potent activity in a HDTX model of CRC stem cell tumors either alone or in combination with 5-FU. Thus, NSC49L as a single agent or combined with 5-FU can be developed as a therapeutic agent by targeting the Chk1 pathway in 5-FU-resistant CRC heterogeneous bulk and CRC stem cell populations.

Parvovirus-Induced Depletion of Cyclin B1 Prevents Mitotic Entry of Infected Cells

PubMed Central

Adeyemi, Richard O.; Pintel, David J.

2014-01-01

Parvoviruses halt cell cycle progression following initiation of their replication during S-phase and continue to replicate their genomes for extended periods of time in arrested cells. The parvovirus minute virus of mice (MVM) induces a DNA damage response that is required for viral replication and induction of the S/G2 cell cycle block. However, p21 and Chk1, major effectors typically associated with S-phase and G2-phase cell cycle arrest in response to diverse DNA damage stimuli, are either down-regulated, or inactivated, respectively, during MVM infection. This suggested that parvoviruses can modulate cell cycle progression by another mechanism. In this work we show that the MVM-induced, p21- and Chk1-independent, cell cycle block proceeds via a two-step process unlike that seen in response to other DNA-damaging agents or virus infections. MVM infection induced Chk2 activation early in infection which led to a transient S-phase block associated with proteasome-mediated CDC25A degradation. This step was necessary for efficient viral replication; however, Chk2 activation and CDC25A loss were not sufficient to keep infected cells in the sustained G2-arrested state which characterizes this infection. Rather, although the phosphorylation of CDK1 that normally inhibits entry into mitosis was lost, the MVM induced DDR resulted first in a targeted mis-localization and then significant depletion of cyclin B1, thus directly inhibiting cyclin B1-CDK1 complex function and preventing mitotic entry. MVM infection thus uses a novel strategy to ensure a pseudo S-phase, pre-mitotic, nuclear environment for sustained viral replication. PMID:24415942

Parvovirus-induced depletion of cyclin B1 prevents mitotic entry of infected cells.

PubMed

Adeyemi, Richard O; Pintel, David J

2014-01-01

Parvoviruses halt cell cycle progression following initiation of their replication during S-phase and continue to replicate their genomes for extended periods of time in arrested cells. The parvovirus minute virus of mice (MVM) induces a DNA damage response that is required for viral replication and induction of the S/G2 cell cycle block. However, p21 and Chk1, major effectors typically associated with S-phase and G2-phase cell cycle arrest in response to diverse DNA damage stimuli, are either down-regulated, or inactivated, respectively, during MVM infection. This suggested that parvoviruses can modulate cell cycle progression by another mechanism. In this work we show that the MVM-induced, p21- and Chk1-independent, cell cycle block proceeds via a two-step process unlike that seen in response to other DNA-damaging agents or virus infections. MVM infection induced Chk2 activation early in infection which led to a transient S-phase block associated with proteasome-mediated CDC25A degradation. This step was necessary for efficient viral replication; however, Chk2 activation and CDC25A loss were not sufficient to keep infected cells in the sustained G2-arrested state which characterizes this infection. Rather, although the phosphorylation of CDK1 that normally inhibits entry into mitosis was lost, the MVM induced DDR resulted first in a targeted mis-localization and then significant depletion of cyclin B1, thus directly inhibiting cyclin B1-CDK1 complex function and preventing mitotic entry. MVM infection thus uses a novel strategy to ensure a pseudo S-phase, pre-mitotic, nuclear environment for sustained viral replication.

Complex engagement of DNA damage response pathways in human cancer and in lung tumor progression.

PubMed

Nuciforo, Paolo Giovanni; Luise, Chiara; Capra, Maria; Pelosi, Giuseppe; d'Adda di Fagagna, Fabrizio

2007-10-01

Tumor initiation and progression provide a multitude of occasions for the generation of DNA damage and the consequent activation of the DNA damage response (DDR) pathway. DDR signaling involves the engagement of key factors such as ATM, CHK2, 53BP1 and the phosphorylation of histone H2AX (gamma-H2AX). The systematic study of DDR in human tumors and normal tissues by high-throughput tissue microarrays revealed that ATM and gamma-H2AX were engaged in cancer but the extent of their activation was strongly affected by the organ and cell type involved, whereas 53BP1 loss was the most consistent feature among the tumor studied. Unexpectedly, we also observed activated DDR markers in morphologically normal tissues, also in association with inflammation. Analysis of the dynamic engagement of DDR along the different stages of lung tumorigenesis showed that 53BP1 loss occurs early at the transition from normal to dysplastic change whereas the activated forms of ATM and CHK2, but not gamma-H2AX, initially accumulate in pre-invasive lesions and are then lost during tumor progression. In individual lung tumors, the activation of ATM, CHK2 and the presence of 53BP1 were consistently correlated, whereas gamma-H2AX did not correlate with activated ATM. Finally, the study of associations between critical clinicopathological parameters and activated DDR factors highlighted a statistically meaningful correlation between reduced local tumor extension and the phosphorylation of ATM, CHK2 and the presence of 53BP1, whereas no significant correlations with parameters such as survival or relapse of early-stage lung carcinomas were found.

Low expression levels of ATM may substitute for CHEK2 /TP53 mutations predicting resistance towards anthracycline and mitomycin chemotherapy in breast cancer

PubMed Central

2012-01-01

Introduction Mutations affecting p53 or its upstream activator Chk2 are associated with resistance to DNA-damaging chemotherapy in breast cancer. ATM (Ataxia Telangiectasia Mutated protein) is the key activator of p53 and Chk2 in response to genotoxic stress. Here, we sought to evaluate ATM's potential role in resistance to chemotherapy. Methods We sequenced ATM and assessed gene expression levels in pre-treatment biopsies from 71 locally advanced breast cancers treated in the neoadjuvant setting with doxorubicin monotherapy or mitomycin combined with 5-fluorouracil. Findings were confirmed in a separate patient cohort treated with epirubicin monotherapy. Each tumor was previously analyzed for CHEK2 and TP53 mutation status. Results While ATM mutations were not associated with chemo-resistance, low ATM expression levels predicted chemo-resistance among patients with tumors wild-type for TP53 and CHEK2 (P = 0.028). Analyzing the ATM-chk2-p53 cascade, low ATM levels (defined as the lower 5 to 50% percentiles) or mutations inactivating TP53 or CHEK2 robustly predicted anthracycline resistance (P-values varying between 0.001 and 0.027 depending on the percentile used to define "low" ATM levels). These results were confirmed in an independent cohort of 109 patients treated with epirubicin monotherapy. In contrast, ATM-levels were not suppressed in resistant tumors harboring TP53 or CHEK2 mutations (P > 0.5). Conclusions Our data indicate loss of function of the ATM-Chk2-p53 cascade to be strongly associated with resistance to anthracycline/mitomycin-containing chemotherapy in breast cancer. PMID:22420423

Design of targeted libraries against the human Chk1 kinase using PGVL Hub.

PubMed

Peng, Zhengwei; Hu, Qiyue

2011-01-01

PGVL Hub is a Pfizer internal desktop tool for chemical library and singleton design. In this chapter, we give a short introduction to PGVL Hub, the core workflow it supports, and the rich design capabilities it provides. By re-creating two legacy targeted libraries against the human checkpoint kinase 1 (Chk1) as a showcase, we illustrate how PGVL Hub could be used to help library designers carry out the steps in library design and realize design objectives such as SAR expansion and improvement in both kinase selectivity and compound aqueous solubility. Finally we share several tips about library design and usage of PGVL Hub.

Alternative Splicing of CHEK2 and Codeletion with NF2 Promote Chromosomal Instability in Meningioma1

PubMed Central

Yang, Hong Wei; Kim, Tae-Min; Song, Sydney S; Shrinath, Nihal; Park, Richard; Kalamarides, Michel; Park, Peter J; Black, Peter M; Carroll, Rona S; Johnson, Mark D

2012-01-01

Mutations of the NF2 gene on chromosome 22q are thought to initiate tumorigenesis in nearly 50% of meningiomas, and 22q deletion is the earliest and most frequent large-scale chromosomal abnormality observed in these tumors. In aggressive meningiomas, 22q deletions are generally accompanied by the presence of large-scale segmental abnormalities involving other chromosomes, but the reasons for this association are unknown. We find that large-scale chromosomal alterations accumulate during meningioma progression primarily in tumors harboring 22q deletions, suggesting 22q-associated chromosomal instability. Here we show frequent codeletion of the DNA repair and tumor suppressor gene, CHEK2, in combination with NF2 on chromosome 22q in a majority of aggressive meningiomas. In addition, tumor-specific splicing of CHEK2 in meningioma leads to decreased functional Chk2 protein expression. We show that enforced Chk2 knockdown in meningioma cells decreases DNA repair. Furthermore, Chk2 depletion increases centrosome amplification, thereby promoting chromosomal instability. Taken together, these data indicate that alternative splicing and frequent codeletion of CHEK2 and NF2 contribute to the genomic instability and associated development of aggressive biologic behavior in meningiomas. PMID:22355270

Fitting the Bill: Commissioned Theatre Projects on Human Rights in Pakistan--The Work of Karachi-Based Theatre Group "Tehrik e Niswan"

ERIC Educational Resources Information Center

Mundrawala, Asma

2007-01-01

Theatre practitioners in Pakistan's southern city Karachi have seen a recent surge of interest in the past two decades by donor agencies from the Western world to fund theatre companies and employ various forms of theatre for development to service their agendas and areas of interest within their target communities. This trend may have lent a…

Perception and knowledge about dietary intake in patients with liver cirrhosis and its relationship with the level of education.

PubMed

Khan, Rustam; Ahmed, Ashfaq; Ismail, Faisal Wasim; Abid, Shahab; Awan, Safia; Shah, Hasnain; Hamid, Saeed; Jafri, Wasim

2012-07-01

To determine patients perception and knowledge regarding diet in cirrhosis and its relationship with the level of patients education. Cross-sectional observational study. This study was conducted at Gastroenterology Outpatient Clinics at the Aga Khan University Hospital, Karachi, the Aga Khan Health Services, Malir, Karachi and Hamdard University, Karachi, from January to December 2010. Consecutive adult patients with compensated cirrhosis were enrolled. Demographic data, level of education, type and reason of food restriction as well as the source of dietary information was asked. Baseline laboratory test were performed, and nutritional status was assessed by BMI normogram. Ninety patients, 58% male were enrolled. Mean age of the patient was 49 ± 11 years. Overall 73% of the patients were restricting fat, meat, fish and eggs in their diet; 53% were in uneducated group and 47% were in educated group (CI, 0.24-1.62, p-0.34). Twenty two patients (62.8%) in uneducated and 21 in educated group (68%) were restricting diet on the advice of their doctors, whereas 13 in uneducated group (37%) and 11 in educated group (32%) believed these dietary components to be harmful for the liver. Thirty two of uneducated patient (71.1%) and 28 of educated patients (62.2%) believed that vegetables, fruits and sugarcane had a beneficial effect on the liver. Main source of dietary information to the patients was the doctor. On sub-group analysis those who restricted diet irrespective of their educational level, had more patients with BMI less than 18.5 kg/m2, (CI 0.01-0.94, p-0.001), haemoglobin less than 12 g/dl (CI 0- 0.03, p-0.001) and serum albumin less than 3 g/dl (CI 0.1- 03, p-0.001). Both educated and uneducated classes of the patients have improper knowledge and perception of diet in cirrhosis. Patients with cirrhosis who restricted diet, had relatively low BMI, haemoglobin and albumin as compared to those who did not restrict. Main source of dietary information to cirrhotic patients were health care personnels.

Ambulatory Treatment of Fast Breathing in Young Infants Aged <60 Days: A Double-Blind, Randomized, Placebo-Controlled Equivalence Trial in Low-Income Settlements of Karachi

PubMed Central

Muhammad, Amber A.; Shafiq, Yasir; Shah, Saima; Kumar, Naresh; Ahmed, Imran; Azam, Iqbal; Pasha, Omrana; Zaidi, Anita K. M.

2017-01-01

Abstract Background. Integrated Management of Childhood Illness recommends that young infants with isolated fast breathing be referred to a hospital for antibiotic treatment, which is often impractical in resource-limited settings. Additionally, antibiotics may be unnecessary for physiologic tachypnea in otherwise well newborns. We tested the hypothesis that ambulatory treatment with oral amoxicillin for 7 days was equivalent (similarity margin of 3%) to placebo in young infants with isolated fast breathing in primary care settings where hospital referral is often unfeasible. Methods. This randomized equivalence trial was conducted in 4 primary health centers of Karachi, Pakistan. Infants presenting with isolated fast breathing and oxygen saturation ≥90% were randomly assigned to receive either oral amoxicillin or placebo twice daily for 7 days. Enrolled infants were followed on days 1–8, 11, and 14. The primary outcome was treatment failure by day 8, analyzed per protocol. The trial was stopped by the data safety monitoring board due to higher treatment failure rate and the occurrence of 2 deaths in the placebo arm in an interim analysis. Results. Four hundred twenty-three infants fulfilled per protocol criteria in the amoxicillin arm and 426 in the placebo arm. Twelve infants (2.8%) had treatment failure in the amoxicillin arm and 25 (5.9%) in the placebo arm (risk difference, 3.1; P value .04). Two infants in the placebo arm died, whereas no deaths occurred in the amoxicillin arm. Other adverse outcomes, as well as the proportions of relapse, were evenly distributed across both study arms. Conclusions. This trial failed to show equivalence of placebo to amoxicillin in the management of isolated fast breathing without hypoxemia or other clinical signs of illness in term young infants. Clinical Trials Registration. NCT01533818. PMID:27941119

Intussusception among children less than 2years of age: Findings from pre-vaccine introduction surveillance in Pakistan.

PubMed

Yousafzai, Mohammad Tahir; Thobani, Rozina; Qazi, Saqib Hamid; Saddal, Nasir; Yen, Catherine; Aliabadi, Negar; Ali, Syed Asad

2017-07-11

Rotavirus vaccination introduction in routine immunization is under consideration in Pakistan. Data on the baseline epidemiology of intussusception will inform surveillance strategies for intussusception after rotavirus vaccine introduction in Pakistan. We describe the epidemiology of intussusception-associated hospitalizations among children <2years of age in Karachi, Pakistan. We conducted a retrospective chart review for July 01, 2012 through June 30, 2015 at the National Institute of Child Health (NICH) and Aga Khan University Hospital (AKUH) Karachi. At AKUH, the International Classification of Disease, ninth revision, code 560.0 for intussusception was used to retrieve intussusception case records. At NICH, daily Operation Theater, Emergency Room, and surgical daycare log sheets and surgical ward census sheets were used to identify cases. Records of children who fulfilled eligibility criteria and the Brighton Collaboration level one case definition of intussusception were selected for data analysis. We used structured case report forms to extract data for the descriptive analysis. We identified 158 cases of confirmed intussusception; 30 cases (19%) were from AKUH. More than half (53%) of the cases occurred in children aged 6-12months, followed by 35% among those aged <6months. Two-thirds (106/158) of the cases were male. The most common presenting complaints were vomiting and bloody stool. At NICH, almost all (93%) were managed surgically, while at AKUH, ∼57% of the cases were managed with enemas. Three deaths occurred, all from NICH. Cases occurred without any seasonality. At NICH, 4% (128/3618) of surgical admissions among children aged <2years were attributed to intussusception, while that for AKUH was 2% (30/1702). In this chart review, intussusception predominantly affected children 0-6months of age and occurred more commonly in males. This information on the baseline epidemiology of intussusception will inform post-vaccine introduction adverse event monitoring related to intussusception in Pakistan. Copyright © 2017 Elsevier Ltd. All rights reserved.

Depression in the elderly: Does family system play a role? A cross-sectional study

PubMed Central

Taqui, Ather M; Itrat, Ahmed; Qidwai, Waris; Qadri, Zeeshan

2007-01-01

Background The most common geriatric psychiatric disorder is depression. The role of family systems in depression among the elderly has not been studied extensively. It has been suggested that urbanization promotes nucleation of family systems and a decrease in care and support for the elderly. We conducted this study in Karachi, a large urban city of Pakistan, to determine the relationship between the type of family system and depression. We also determined the prevalence of depression in the elderly, as well as correlation of depression with other important socio-demographic variables. Methods A cross-sectional study was carried out in the premises of a tertiary care hospital in Karachi, Pakistan. Questionnaire based interviews were conducted among the elderly people visiting the hospital. Depression was assessed using the 15-item Geriatric Depression Scale. Results Four hundred subjects aged 65 and above were interviewed. The age of majority of the subjects ranged from 65 to 74 years. Seventy eight percent of the subjects were male. The prevalence of depression was found to be 19.8%. Multiple logistic regression analysis revealed that the following were significant (p < 0.05) independent predictors of depression: nuclear family system, female sex, being single or divorced/widowed, unemployment and having a low level of education. The elderly living in a nuclear family system were 4.3 times more likely to suffer from depression than those living in a joint family system (AOR = 4.3 [95% CI = 2.4–7.6]). Conclusion The present study found that residing in a nuclear family system is a strong independent predictor of depression in the elderly. The prevalence of depression in the elderly population in our study was moderately high and a cause of concern. The transition in family systems towards nucleation may have a major deleterious effect on the physical and mental health of the elderly. PMID:17961255

Hyperbilirubinaemia a predictive factor for complicated acute appendicitis: a study in a tertiary care hospital.

PubMed

Jamaluddin, Muhammad; Hussain, Syed Mohammad Abbas; Ahmad, Humaid

2013-11-01

To study the role of hyperbilirubinaemia as a predictive factor for appendiceal perforation in acute appendicitis. The prospective, descriptive study was conducted at the Abbasi Shaheed Hospital and the Karachi Medical and Dental College, Karachi, from January 2010 to June 2012. It comprised all patients coming to the surgical outpatient department and emergency department with pain in the right iliac fossa with duration less than seven days. They were clinically assessed for signs and symptoms of acute appendicitis and relevant tests were conducted. Patients were diagnosed as a case of acute appendicitis on the basis of clinical and ultrasound findings, and were prepared for appendicectomy. Per-operative findings were recorded and specimens were sent for histopathology to confirm the diagnosis. SPSS version 10 was used to analyse the data. Of the 71 patients, 37 (52.10%) were male and 34 (47.90%) were female. The age range was 3-57 years, and most of the patients (n = 33; 46.5%) were between 11 and 20 years. Besides, 63 (89%) patients had pain in the right iliac fossa of less than four-days duration, while 8 (11%) had pain of longer duration.Total leukocyte count was found to be elevated in 33 (46.5%) patients, while total serum bilirubin was elevated in 41 (57.70%). Ultrasound of abdomen showed 9 (12.70%) patients having normal appearance of appendix and 59 (83.30%) had inflamed appendix. Four (5.60%) patients had no signs of inflammation on naked eye appearance per operatively. Histopathology of appendix showed 10 (14.10%) patients had non-inflammatory appendix. Patients with signs and symptoms of acute appendicitis and a raised total serum bilirubin level indicated a complication of acute appendicitis requiring an early intervention to prevent peritonitis and septicaemia. A raised serum bilirubin level is a good indicator of complicated acute appendicitis, and should be included in the assessment of patients with suspected complicated acute appendicitis.

Awareness and perceptions of electroconvulsive therapy among psychiatric patients: a cross-sectional survey from teaching hospitals in Karachi, Pakistan.

PubMed

Arshad, Mehreen; Arham, Ahmad Zafir; Arif, Mansoor; Bano, Maria; Bashir, Ayisha; Bokutz, Munira; Choudhary, Maria Maqbool; Naqvi, Haider; Khan, Murad Moosa

2007-06-21

Electroconvulsive therapy (ECT) is shown to be effective in many psychiatric illnesses, but its distorted projection by the Pakistani media and its unregulated use by many physicians across the country have adversely affected its acceptability. Given this situation we aimed to assess the awareness and perceptions regarding ECT as a treatment modality among the psychiatric patients. This was a questionnaire based cross-sectional study carried out at 2 tertiary care hospitals in Karachi, Pakistan. We interviewed 190 patients of which 140 were aware of ECT. The study showed that the level of education had a significant impact on the awareness of ECT (p = 0.009). The most common source of awareness was electronic and print media (38%), followed by relatives (24%) and doctors (23%). Physical injuries (42%) and neurological (12%) and cognitive disturbances (11%) were the commonly feared side effects. The most popular belief about ECT was that it was a treatment of last resort (56%). Thirty-nine percent thought that ECT could lead to severe mental and physical illness and 37% considered it inhumane. Patients' willingness to receive ECT was dependant on whether or not they were convinced of its safety (p = 0.001) and efficacy (p = 0.0001). We identified a serious lack of dissemination of information regarding ECT by the psychiatrists and the mental health care providers. This may be the result of an inadequate postgraduate training in Pakistan or just a lack of concern about the mentally ill patients. The media seemed to be the major source of information for our patients. We also saw the prevalence of a variety of myths regarding ECT in our society, which we feel may be responsible for the patients' adverse attitudes. Given the widespread applicability of ECT there is a dire need to dispel these misconceptions and improve its acceptability.

A prospective study of outcome from rubber band ligation in third degree haemorrhoids.

PubMed

Khan, Asma Niaz; Khan, Naveed Ali

2010-11-01

To evaluate the efficacy and effectiveness of rubber band ligation on 3rd degree haemorrhoids. Study was done at Surgical Unit, Civil Hospital Karachi, during a period of 19 months from December 2006 to July 2008. Out of 344 patients 80 patients were included in the study with 3rd degree internal haemorrhoids and were treated with Rubber band ligation (RBL). Outcome data was recorded for success of treatment. Among 80 patients, 77 (96.25%) were symptom free. After completion of treatment, 1 (16.66%) out of 5 patients had the complaint of pain, 2 (2.85%) out of 70 had complaints of constipation. Before start of treatment 5 (6.25%) patients complained of bleeding per rectum and 73 (91.25%) complained of manually reducible/prolapsed haemorrhoids. Both complaints were cured 100% after treatment. RBL is an efficient, cost-effective and simple out patient procedure for symptomatic third degree haemorrhoids with minimum complications. RBL is a reliable, safe procedure requiring no hospitalization and no use of any anaesthetic drugs.

Group psychological intervention for maternal depression: A nested qualitative study from Karachi, Pakistan.

PubMed

Husain, Nusrat; Chaudhry, Nasim; Furber, Christine; Fayyaz, Hina; Kiran, Tayyeba; Lunat, Farah; Rahman, Raza Ur; Farhan, Saira; Fatima, Batool

2017-06-22

To understand the experience of maternal depression, the factors implicated in accessing health, and the acceptability of the psychosocial intervention. The participants were recruited from the paediatrics outpatient department of Civil Hospital Karachi, Pakistan. The study started in December 2009 and completed in December 2010. Women with maternal depression, aged 18-44 years with children aged 0-30 mo who had received nutritional supplements, and participated in the intervention programme [called Learning through Play (LTP) plus] were included in the study. Qualitative interviews were conducted with 8 participants before the intervention and 7 participants after the intervention. A semi structured topic guide was used to conduct the interviews. Framework analysis procedures were used to analyse the qualitative data. Four themes emerged: (1) the women's contextual environment: Interpersonal conflicts, lack of social support and financial issues being the major barriers in assessing healthcare; (2) women's isolation and powerlessness within the environment: Sense of loneliness was identified as a restricting factor to access healthcare; (3) the impact of the intervention (LTP-Plus): Women felt "listened to" and seemed empowered; and (4) empowered transformed women within the same contextual environment: The facilitator provided a "gardening role" in nurturing the women resulting in a positive transformation within the same environment. The women's homes seemed to be more happy homes and there was a positive change in their behaviour towards their children. Findings informed the further development and testing of culturally-appropriate psychosocial intervention (LTP + ) for addressing maternal depression.

Checkpoint-dependent and independent roles of the Werner syndrome protein in preserving genome integrity in response to mild replication stress

PubMed Central

Basile, Giorgia; Leuzzi, Giuseppe; Pichierri, Pietro; Franchitto, Annapaola

2014-01-01

Werner syndrome (WS) is a human chromosomal instability disorder associated with cancer predisposition and caused by mutations in the WRN gene. WRN helicase activity is crucial in limiting breakage at common fragile sites (CFS), which are the preferential targets of genome instability in precancerous lesions. However, the precise function of WRN in response to mild replication stress, like that commonly used to induce breaks at CFS, is still missing. Here, we establish that WRN plays a role in mediating CHK1 activation under moderate replication stress. We provide evidence that phosphorylation of CHK1 relies on the ATR-mediated phosphorylation of WRN, but not on WRN helicase activity. Analysis of replication fork dynamics shows that loss of WRN checkpoint mediator function as well as of WRN helicase activity hamper replication fork progression, and lead to new origin activation to allow recovery from replication slowing upon replication stress. Furthermore, bypass of WRN checkpoint mediator function through overexpression of a phospho-mimic form of CHK1 restores fork progression and chromosome stability to the wild-type levels. Together, these findings are the first demonstration that WRN regulates the ATR-checkpoint activation upon mild replication stress, preventing chromosome fragility. PMID:25352544

[Effect of andrographolide on quorum sensing and relevant virulence genes of Candida albicans].

PubMed

Yan, Yuan-yuan; Shi, Gao-xiang; Shao, Jing; Lu, Ke-qiao; Zhang, Meng-xiang; Wang, Tian-ming; Wang, Bin; Wang, Chang-zhong

2015-01-01

To investigate the effect of andrographolide (AG) on quroum sensing (QS) and relevant virulence genes of Candida albicans. Gas-chromatography-mass spectrometry (GC-MS) was applied to detect the changes in the content of farnesol and tyrosol in C. albicans intervened by AG. The real-time quantitative PCR (qRT-PCR) was adopted to inspect the expressions of relevant virulence genes such as CHK1, PBS2 and HOG1 regulated by QS. At 2 h after the growth of C. albican, the farnesol and tyrosol secretions reduced, without notable change after intervention with AG. The secretions were highest at 12 h and decreased at 24 h. After the intervention with different concentrations of AG, the farnesol content reduces, whereas tyrosol increased, indicating a dose-dependence, particularly with 1 000 mg x L(-1) AG. qRT-PCR revealed that 1 000 mg x L(-1) AG could down-regulate CHK1 by 2.375, 3.330 and 4.043 times and PBS2 by 2.010, 4.210 and 4.760 times, with no significant change in HOG1. AG could inhibit the farnesol secretion, promote the tyrosol secretion and down-regulate QS-related virulence genes CHK1 and PBS2 expressions.

Screening of a library of T7 phage-displayed peptides identifies alphaC helix in 14-3-3 protein as a CBP501-binding site.

PubMed

Matsumoto, Yuki; Shindo, Yosuke; Takakusagi, Yoichi; Takakusagi, Kaori; Tsukuda, Senko; Kusayanagi, Tomoe; Sato, Hitoshi; Kawabe, Takumi; Sugawara, Fumio; Sakaguchi, Kengo

2011-12-01

CBP501 is a chemically modified peptide composed of twelve unnatural d-amino acids, which inhibits Chk kinase and abrogates G2 arrest induced by DNA-damaging agents. Here we identified an alphaC helix in 14-3-3 protein as a CBP501-binding site using T7 phage display technology. An affinity selection of T7 phage-displayed peptide using biotinylated CBP501 identified a 14-mer peptide NSDCIISRKIEQKE. This peptide sequence showed similarity to a portion of the alphaC helix of human 14-3-3ε, suggesting that CBP501 may bind to this region. Surface plasmon resonance (SPR) and ELISA demonstrated that CBP501 interacts with 14-3-3ε specifically at the screen-guided region. An avidin-agarose bead pull-down assay showed that CBP501 also binds to other 14-3-3 isoforms in Jurkat cells. Among the other known Chk kinase inhibitors tested, CBP501 showed the strongest affinity for 14-3-3ε. Thus, we conclude that in addition to the direct inhibition of Chk kinase activity, CBP501 directly binds to cellular 14-3-3 proteins through alphaC helix. Copyright © 2011 Elsevier Ltd. All rights reserved.

Effects of Camphorquinone on Cytotoxicity, Cell Cycle Regulation and Prostaglandin E2 Production of Dental Pulp Cells: Role of ROS, ATM/Chk2, MEK/ERK and Hemeoxygenase-1

PubMed Central

Chang, Mei-Chi; Lin, Li-Deh; Wu, Min-Tsz; Chan, Chiu-Po; Chang, Hsiao-Hua; Lee, Ming-Shu; Sun, Tzu-Ying; Jeng, Po-Yuan; Yeung, Sin-Yuet; Lin, Hsueh-Jen; Jeng, Jiiang-Huei

2015-01-01

Camphorquinone (CQ) is a popularly-used photosensitizer in composite resin restoration. In this study, the effects of CQ on cytotoxicity and inflammation-related genes and proteins expression of pulp cells were investigated. The role of reactive oxygen species (ROS), ATM/Chk2/p53 and hemeoxygenase-1 (HO-1) and MEK/ERK signaling was also evaluated. We found that ROS and free radicals may play important role in CQ toxicity. CQ (1 and 2 mM) decreased the viability of pulp cells to about 70% and 50% of control, respectively. CQ also induced G2/M cell cycle arrest and apoptosis of pulp cells. The expression of type I collagen, cdc2, cyclin B, and cdc25C was inhibited, while p21, HO-1 and cyclooxygenase-2 (COX-2) were stimulated by CQ. CQ also activated ATM, Chk2, and p53 phosphorylation and GADD45α expression. Besides, exposure to CQ increased cellular ROS level and 8-isoprostane production. CQ also stimulated COX-2 expression and PGE2 production of pulp cells. The reduction of cell viability caused by CQ can be attenuated by N-acetyl-L-cysteine (NAC), catalase and superoxide dismutase (SOD), but can be promoted by Zinc protoporphyin (ZnPP). CQ stimulated ERK1/2 phosphorylation, and U0126 prevented the CQ-induced COX-2 expression and prostaglandin E2 (PGE2) production. These results indicate that CQ may cause cytotoxicity, cell cycle arrest, apoptosis, and PGE2 production of pulp cells. These events could be due to stimulation of ROS and 8-isoprostane production, ATM/Chk2/p53 signaling, HO-1, COX-2 and p21 expression, as well as the inhibition of cdc2, cdc25C and cyclin B1. These results are important for understanding the role of ROS in pathogenesis of pulp necrosis and pulpal inflammation after clinical composite resin filling. PMID:26658076

Food insecurity in metropolis of the developing world--observations from central district of Karachi, Pakistan.

PubMed

Hakeem, R; Asar, F; Shaikh, A H

2003-11-01

To assess the prevalence of household food insecurity at various income levels in urban areas of Karachi. A cross sectional survey of different localities in the central district of Karachi was carried out. The data was collected through household interviews of housewives conducted by trained nutritionist. Housewives were interviewed about food security status of the household. A total of 797 families were visited from the central district of Karachi. Mean Food Security Score increased with income level. The difference was statistically significant (ANOVA) between 1st and second (P=0.000) and 2nd and 3rd group (P=0.000) but not between 3rd and fourth group. At the very low and low income levels 83% & 51% families respectively were food insecure in any degree, while this percentage was very low at the middle (6.3%) and high income level (1.8%). The difference in prevalence of food insecurity between the VLI and LI, and, LI and MI income groups was statistically significant (chi.sq. test, p<0.001 in each case). Hunger (because of lack of money) was experienced in the preceding year only by "very low income" (37%) and "low income" families (17%). Use of coping strategies was most frequently mentioned for parents and then for children and only occasionally for infants or grand parents. Females were more likely to be effected by food insecurity than males. Meat, milk and fruits were the food groups which were preferred and considered healthy but were avoided because of lack of money by a majority (51%-86%) of families. In spite of having an impression of being an affluent city of Pakistan, the prevalence of food insecurity with and without hunger is rampant not only among very low income (slum dwellers) but also among low income families of Karachi.

Drinking water contamination by chromium and lead in industrial lands of Karachi.

PubMed

Nadeem-ul-Haq; Arain, Mubashir Aslam; Haque, Zeba; Badar, Nasira; Mughal, Noman

2009-05-01

To identify and quantify chromium and lead as contaminant in water sources of Karachi. This water assessment survey was conducted from June 2007 to February 2008 in all the 18 towns of Karachi. In total 216 water samples were collected from ground (n=108) and surface water sources (n = 108). Water samples were collected in a liter polyethylene acid resistant bottle with extreme care to prevent contamination and concentrations of heavy metals (chromium and lead). Metallic ion contents were estimated by Atomic Absorption Spectrophotometer. Statistical analysis was done by applying T-test and chi-square for continuous and categorical variables respectively at 95% confidence level; Pearson correlation was also determined between chromium and lead concentrations. A total of 187 water samples had lead concentration higher than the maximum acceptable concentration (MAC) in drinking water, established by WHO (10 PPB) and lead contaminated sources were in significantly higher proportion than chromium contaminated water samples (n = 49) [chi2 = 128; P- < 0.001]. Mean chromium concentration in ground water was (micro = 49; SE = 3.8) was significantly higher than mean chromium concentration (micro = 33, SE = 3.5) in surface water (P = 0.003). There was a significant and positive correlation between chromium and lead concentrations in ground water (P = 0.04) however Pearson correlation was not significant for surface water (P = 0.6). Industrial towns (Korangi, Landhi and SITE) had significantly higher concentration of chromium (micro = 82.4; SE = 8.9) in their ground and tap water as compared to the mean chromium concentration (micro = 33; SE = 2.2) in the water samples of rest of the towns of Karachi (P < 0.001). Chromium and Lead levels are high in almost all ground water sources, however extremely high concentrations were found in industrial areas. Presence of any one of the heavy metal contamination necessitate the need for the estimation of other heavy metals as significant positive correlation was found between chromium and lead concentration, indicating the possibility of similar contamination sources in Karachi.

Reasons behind the increase in research activities among medical students of Karachi, Pakistan, a low-income country.

PubMed

Baig, Shoukat Ali; Hasan, Syed Askari; Ahmed, Syed Mustajab; Ejaz, Kiran; Aziz, Sina; Dohadhwala, Nava Asad

2013-01-01

Previously, in a low-income country with limited resources like Pakistan, biomedical research was conducted mostly by individuals working in private organizations. Recently, there has been an upsurge in the number of medical students conducting research in both private and public medical colleges of Karachi, Pakistan. We investigated student perceptions of the reasons behind the increase in biomedical research among medical students of private and public medical colleges in Karachi, Pakistan. This cross-sectional study was conducted at four medical universities of Karachi, using structured data collection tool. Participants included medical students who stated that they were interested in medical research. We assessed how many had been involved in research or stated that they intended to be, and tallied students' stated reasons why they were involved in research. Chi-square analyses were used to assess if year of training, institution, and other factors were associated with the likelihood of past or current actual research involvement. Out of the 398 students with research interest who participated in the study, 349 (88%) stated that they intended to do research projects in their undergraduate years. At the time of the study, only 202 (51%) reported that they had actually conducted research. The reasons given for engaging in research for a minority included personal interest (n = 136; 34%), while majority stated that their motivation was to improve their curriculum vitae (75%) and/or to be more competitive for a residency in the United States (43%). The reasons students gave for involvement in research were related to whether their schools were public versus private and to their year of study. According to students' reports, improving one's curriculum vitae to get a strong residency in the USA appeared to be a principal reason for the increase in biomedical research in Karachi. The challenges of research, such as lack of good mentors and increased work-load were reported to affect few students' ability to engage in research.

Assessment of gallstone predictor: comparative analysis of ultrasonographic and biochemical parameters

PubMed Central

2013-01-01

Background Gallstones represent a significant burden for health care systems worldwide and are one of the most common disorders presenting to emergency room. Ultrasonography, complete blood picture test and liver function tests are procedures of choice in suspected gallstones or biliary diseases. They are the most sensitive, specific, non-invasive and inexpensive tests for the detection of gallstones. Our main objective was to evaluate the relationship of ultrasonographic findings, hemolytic indices and liver function tests with gallstones. Methodology It was a prospective study carried out in Civil Hospital Karachi (DUHS) and Liaquat National Hospital, two largest tertiary care hospitals of Karachi, Pakistan. Duration of the study was from July 2011 to October 2012. The study was carried out on diagnosed, pre-operative and symptomatic patients of cholelithiases. Exclusion criteria were patients of gallbladder and pancreatic carcinoma, emergency operations, patients having age <12 years and non-cooperative patients, who refused to give written consent for participation in the study. Total two tests were performed on each patient after diagnosis by ultrasonography. These were complete blood count and liver function tests. All the demographic data, laboratory findings and ultrasonographic features were noted in a pre-structured Performa. Sample size was calculated by using open-epidemiological sample size calculator prevalence (p) = 35%, d = 5%, and confidence interval (CI) 95% = 350. All the data was entered and analyzed through SPSS 19. Result There were 454 diagnosed and pre-operative cases of gallstones present in the study. There were 120(26.4%) males and 334(73.6%) females, with a mean age of 42.80 ± 12.26 years. Most of the suspects had multiple stones 384 (84.5%) while few had single stones 70(15.4%). Fatty liver was found to be present in 144(31.7%) patients and 92(20.2%) had hepatomegaly. Splenomegaly was present in 16(3.5%) patients. Alkaline phosphatase was elevated in 186(41.0%) patients while SGPT was found to be raised in 160(35.2%). Blood urea nitrogen was found to be elevated in 186(41%) patients and serum creatinine was elevated in 46(10.1%) patients. Conclusion In the light of findings it is recommend that all patients should go through the process of ultrasonography and all the biochemical parameters should be analyzed before surgery. PMID:23618353

Assessment of gallstone predictor: comparative analysis of ultrasonographic and biochemical parameters.

PubMed

Aslam, Hafiz Muhammad; Saleem, Shafaq; Edhi, Muhammad Muzzammil; Shaikh, Hiba Arshad; Khan, Jehanzeb Daniel; Hafiz, Mehak; Saleem, Maria

2013-01-01

Gallstones represent a significant burden for health care systems worldwide and are one of the most common disorders presenting to emergency room. Ultrasonography, complete blood picture test and liver function tests are procedures of choice in suspected gallstones or biliary diseases. They are the most sensitive, specific, non-invasive and inexpensive tests for the detection of gallstones. Our main objective was to evaluate the relationship of ultrasonographic findings, hemolytic indices and liver function tests with gallstones. It was a prospective study carried out in Civil Hospital Karachi (DUHS) and Liaquat National Hospital, two largest tertiary care hospitals of Karachi, Pakistan. Duration of the study was from July 2011 to October 2012. The study was carried out on diagnosed, pre-operative and symptomatic patients of cholelithiases. Exclusion criteria were patients of gallbladder and pancreatic carcinoma, emergency operations, patients having age <12 years and non-cooperative patients, who refused to give written consent for participation in the study. Total two tests were performed on each patient after diagnosis by ultrasonography. These were complete blood count and liver function tests. All the demographic data, laboratory findings and ultrasonographic features were noted in a pre-structured Performa. Sample size was calculated by using open-epidemiological sample size calculator prevalence (p) = 35%, d = 5%, and confidence interval (CI) 95% = 350. All the data was entered and analyzed through SPSS 19. There were 454 diagnosed and pre-operative cases of gallstones present in the study. There were 120(26.4%) males and 334(73.6%) females, with a mean age of 42.80 ± 12.26 years. Most of the suspects had multiple stones 384 (84.5%) while few had single stones 70(15.4%). Fatty liver was found to be present in 144(31.7%) patients and 92(20.2%) had hepatomegaly. Splenomegaly was present in 16(3.5%) patients. Alkaline phosphatase was elevated in 186(41.0%) patients while SGPT was found to be raised in 160(35.2%). Blood urea nitrogen was found to be elevated in 186(41%) patients and serum creatinine was elevated in 46(10.1%) patients. In the light of findings it is recommend that all patients should go through the process of ultrasonography and all the biochemical parameters should be analyzed before surgery.

Injection practices among practitioners in private medical clinics of Karachi, Pakistan.

PubMed

Yousafzai, M T; Nisar, N; Kakakhel, M F; Qadri, M H; Khalil, R; Hazara, S M

2013-06-01

The aim of this study was to determine the frequency and determinants of sharps injuries among private health practitioners in slum areas of Karachi, Pakistan. All practitioners with at least 1 year of experience in a private medical clinic were asked to complete a self-administered, structured questionnaire (317/397 responded). Only 7.9% of practitioners were qualified from medical school, 12.3% were registered nurses and 8.8% lacked any professional qualifications. At least 1 sharps injury in the previous 12 months was reported by 26.7%, mostly due to needle recapping. Only 25.2% reported using a new syringe for each patient. In multivariate regression analysis shorter work experience, < 14 years of schooling, > 20 patients per day, administering > or = 30 injections per day, reuse of syringes and needle recapping after use were significantly associated with sharps injury in the past year. Better awareness and training on standard precautions is needed for private practitioners in slum areas of Karachi.

Psychosocial correlates, psychological distress, and quality of life in patients with medically unexplained symptoms: a primary care study in Karachi, Pakistan.

PubMed

Husain, Muhammad Ishrat; Chaudhry, Nasim; Morris, Julie; Zafar, Shehla Naeem; Jaffery, Farhat; Rahman, Raza; Duddu, Venu; Husain, Nusrat

2015-01-01

To examine the psychosocial correlates and association of psychological distress and quality of life (QOL) in patients with medically unexplained symptoms (MUS) compared to those with medically explained symptoms (MES) in a primary care setting in Karachi, Pakistan. A cross-sectional study of 472 patients attending GP clinics between March and August 2009 in Karachi. Participants completed questionnaires to assess demographic details, somatic symptoms, anxiety, depression, and QOL. The patients' GP recorded whether the presenting complaint was medically unexplained or medically explained. MUS subjects in our study were more educated, had better social support and fewer financial problems, were less depressed and had a better QOL than subjects who had medically explained symptoms (non-MUS). Both groups (MUS and non-MUS) were comparable in terms of anxiety and number of somatic symptoms, but non-MUS subjects were more depressed than the MUS group. In a regression analysis, the number of somatic symptoms and lower levels of anxiety predicted poorer QOL in this sample. Whether these symptoms were medically explained (or not) did not seem to contribute significantly to the QOL. Our findings confirm that even in the developing world, patients with MUS are common among primary care attendees. However, patients with MUS in urban Karachi, Pakistan may differ from Western MUS subjects in the role of stress, support, and anxiety in their presentation, and may be reflective of a conceptually different group of difficulties. © 2015, The Author(s).

Chronic Bronchitis and Chronic Obstructive Pulmonary Disease (COPD) Among Textile Workers in Karachi, Pakistan.

PubMed

Nafees, Asaad Ahmed; Fatmi, Zafar; Kadir, Muhammad Masood; Sathiakumar, Nalini

2016-05-01

To determine the frequency and predictors of chronic bronchitis and COPD among textile workers in Karachi, Pakistan. Cross-sectional survey. Karachi, Pakistan, from October to December 2009. Male textile workers from 15 mills of Karachi were inducted. Data was collected using American Thoracic Society respiratory questionnaire (ATS-DLD-78-a) and spirometry. Out of 372 participants, 29 (7.8%) workers had chronic bronchitis (4, 9.1% aged ≥40 years) and 25 (6.7%) had COPD (12, 27.2% aged ≥40 years). Workers with chronic bronchitis had significantly decreased lung function compared to the healthy workers. Those reporting severe self-perceived dust exposure at work, ≥ 10 pack years of smoking, uneducated, longer duration of work (≥11 years), and ever smokers were more likely to have chronic bronchitis or COPD. In the multivariate analyses, severe self-perceived dust exposure at work (AOR = 7.4; 95% CI: 1.9, 28.0), family history of respiratory illness/symptoms (AOR = 4.8; 95% CI: 1.1, 20.9) and lack of education (AOR = 4.2; 95% CI: 1.1, 16.9) were significant predictors of chronic bronchitis. Duration of work ≥11 years (AOR = 5.5; 95% CI: 1.5, 19.7) and pack years of smoking ≥10 years (AOR = 3.5; 95% CI: 1.1, 11.7) were strong predictors for COPD. There is a high frequency of chronic bronchitis and COPD among textile workers. Multiple important predictors for prevention are identified.

Impact and correlation of environmental conditions on pollen counts in Karachi, Pakistan.

PubMed

Perveen, Anjum; Khan, Muneeba; Zeb, Shaista; Imam, Asif Ali

2015-02-01

A quantitative and qualitative survey of airborne pollen was performed in the city of Karachi, and the pollen counts were correlated with different climatic conditions. The aim of the study was to determine the possible effect of meteorological factors on airborne pollen distribution in the atmosphere of Karachi city. Pollen sampling was carried out by using Burkard spore Trap for the period of August 2009 to July 2010, and a total of 2,922 pollen grains/m(3) were recorded. In this survey, 22 pollen types were recognized. The highest pollen count was contributed by Poaceae pollen type (1,242 pollen grains/m(3)) followed by Amaranthaceae/Chenopodiaceae (948 pollen grains/m(3)), Cyperus rotundus (195 pollen grains/m(3)) and Prosopis juliflora (169 pollen grains/m(3)). Peak pollen season was in August showing a total of 709 pollen grains/m(3) and lowest pollen count was observed in January-2010. Pearson's chi-square test was performed for the possible correlation of pollen counts and climatic factors. The test revealed significant positive correlation of wind speed with pollen types of Amaranthaceae/Chenopodiaceae; Brassica campestris; Asteraceae; and Thuja orientalis. While the correlation of "average temperature" showed significant positive value with Asteraceae and Tamarix indica pollen types. Negative correlation was observed between humidity/ precipitation and pollen types of Brassica campestris; Daucus carota; Ephedra sp.; and Tamarix indica. In the light of above updated data one could identify various aeroallergens present in the air of Karachi city.

Ego defense mechanisms in Pakistani medical students: a cross sectional analysis.

PubMed

Parekh, Maria A; Majeed, Hina; Khan, Tuba R; Khan, Anum B; Khalid, Salman; Khwaja, Nadia M; Khalid, Roha; Khan, Mohammad A; Rizqui, Ibrahim M; Jehan, Imtiaz

2010-01-29

Ego defense mechanisms (or factors), defined by Freud as unconscious resources used by the ego to reduce conflict between the id and superego, are a reflection of how an individual deals with conflict and stress. This study assesses the prevalence of various ego defense mechanisms employed by medical students of Karachi, which is a group with higher stress levels than the general population. A questionnaire based cross-sectional study was conducted on 682 students from five major medical colleges of Karachi over 4 weeks in November 2006. Ego defense mechanisms were assessed using the Defense Style Questionnaire (DSQ-40) individually and as grouped under Mature, Immature, and Neurotic factors. Lower mean scores of Immature defense mechanisms (4.78) were identified than those for Neurotic (5.62) and Mature (5.60) mechanisms among medical students of Karachi. Immature mechanisms were more commonly employed by males whereas females employed more Neurotic mechanisms than males. Neurotic and Immature defenses were significantly more prevalent in first and second year students. Mature mechanisms were significantly higher in students enrolled in Government colleges than Private institutions (p < 0.05). Immature defense mechanisms were less commonly employed than Neurotic and Mature mechanisms among medical students of Karachi. The greater employment of Neurotic defenses may reflect greater stress levels than the general population. Employment of these mechanisms was associated with female gender, enrollment in a private medical college, and students enrolled in the first 2 years of medical school.

Assessment of fertility control efforts in a selected area of Karachi, Pakistan.

PubMed

Shirmeen, Amra; Khan, Muhammad F H; Khan, Khizer H; Khan, Khurum H

2007-09-01

To investigate the impact of fertility control efforts on reducing fertility and to study the contributory role of fertility inhibiting factors viz, age of the marriage, breast feeding and post-partum amenorrhea, abortion and use of contraceptives in selected area in Karachi, Pakistan. The aim was to estimate the gap between knowledge of contraceptives and its practice i.e. KAP-GAP as well as to determine the level of unmet need in the PIB colony in Karachi. A sample survey was conducted in PIB colony in Karachi from October 2005 to November 2005 by interviewing 340 married women in reproductive ages. The data was tabulated and John Bongaarts technique was used to analyse the success of fertility control efforts in the selected area. Of the total of 340 respondents, 38% were currently using contraceptive methods with 26% using OCP's and 12% were condom users. A slight reduction in total fertility (TFR) was noticed. The population policy of Pakistan envisages achieving population stabilization in 2020 by reducing the annual rate of population growth from 1.9% to 1.3% and TFR at 2.1. This target requires strenuous efforts to make the concept of small family an accepted milieu through an eagerly designed communication and education campaign. Concentration on proximate determinants of fertility particularly breast feeding and prolonging birth interval will not generate opposition from the community because these concepts are in accordance with Islamic injunctions and teachings.

Asymptomatic urinary tract infection: Cause of postoperative wound infection.

PubMed

Ashraf, Irfan; Umer, Masood

2014-12-01

To determine the rate of urinary tract infection in patients given incomplete treatment before undergoing hip fracture surgery. The descriptive case series was conducted at Aga Khan University Hospital, Karachi, From October 25, 2012 to April 24, 2013. 84 postmenopausal women having hip fracture along with asymptomatic urinary tract infection. The infection was treated incompletely and postoperatively wound infection rate was determined. The SPSS version 17 was used to analyze the data. The overall mean age of the 84 patients in the study was 63.57+10.34 years. Overall, 14(16.7%) patients had wound infection after orthopaedic implant surgery for hip fracture. There was a high occurrence of wound infection after hip implant surgery in patients having preoperative asymptomatic urinary tract infection who were treated incompletely.

Self-esteem and obsessive compulsive disorder.

PubMed

Husain, Nusrat; Chaudhry, Imran; Raza-ur-Rehman; Ahmed, Ghazal Riaz

2014-01-01

To explore the association between self-esteem and obsessive compulsive disorder in a low-income country, and to conduct an in-depth analysis into the said relationship by identifying any confounding variables that might exist. The cross-sectional study was conducted at the psychiatry out-patient clinic of Civil Hospital, Karachi, from January to March 2008, and comprised 65 patients diagnosed with obsessive compulsive disorder and 30 healthy controls. The participatnts completed the Janis and Field Social Adequacy scale and the Rosenberg Self-esteem scale. SPSS 15 was used for statistical analysis. Significantly different scores were reported on both measures of self-esteem between the patients and the controls (p<0.001 each), indicating reduced levels of self-esteem in the patients compared to the controls. Data replicated earlier findings from populations in high-income countries.

Mutant p53 establishes targetable tumor dependency by promoting unscheduled replication

PubMed Central

Singh, Shilpa; Vaughan, Catherine A.; Frum, Rebecca A.; Grossman, Steven R.; Deb, Sumitra

2017-01-01

Gain-of-function (GOF) p53 mutations are observed frequently in most intractable human cancers and establish dependency for tumor maintenance and progression. While some of the genes induced by GOF p53 have been implicated in more rapid cell proliferation compared with p53-null cancer cells, the mechanism for dependency of tumor growth on mutant p53 is unknown. This report reveals a therapeutically targetable mechanism for GOF p53 dependency. We have shown that GOF p53 increases DNA replication origin firing, stabilizes replication forks, and promotes micronuclei formation, thus facilitating the proliferation of cells with genomic abnormalities. In contrast, absence or depletion of GOF p53 leads to decreased origin firing and a higher frequency of fork collapse in isogenic cells, explaining their poorer proliferation rate. Following genome-wide analyses utilizing ChIP-Seq and RNA-Seq, GOF p53–induced origin firing, micronuclei formation, and fork protection were traced to the ability of GOF p53 to transactivate cyclin A and CHK1. Highlighting the therapeutic potential of CHK1’s role in GOF p53 dependency, experiments in cell culture and mouse xenografts demonstrated that inhibition of CHK1 selectively blocked proliferation of cells and tumors expressing GOF p53. Our data suggest the possibility that checkpoint inhibitors could efficiently and selectively target cancers expressing GOF p53 alleles. PMID:28394262

UCN-01 enhances cytotoxicity of irinotecan in colorectal cancer stem-like cells by impairing DNA damage response

PubMed Central

Pilozzi, Emanuela; De Luca, Gabriele; Cappellari, Marianna; Fanciulli, Maurizio; Goeman, Frauke; Melucci, Elisa; Biffoni, Mauro; Ricci-Vitiani, Lucia

2016-01-01

Colorectal cancer (CRC) is one of the most common and lethal cancers worldwide. Despite recent progress, the prognosis of advanced stage CRC remains poor, mainly because of cancer recurrence and metastasis. The high morbidity and mortality of CRC has been recently ascribed to a small population of tumor cells that hold the potential of tumor initiation, i.e. cancer stem cells (CSCs), which play a pivotal role in cancer recurrence and metastasis and are not eradicated by current therapy. We screened CRC-SCs in vitro with a library of protein kinase inhibitors and showed that CRC-SCs are resistant to specific inhibition of the major signaling pathways involved in cell survival and proliferation. Nonetheless, broad-spectrum inhibition by the staurosporin derivative UCN-01 blocks CRC-SC growth and potentiates the activity of irinotecan in vitro and in vivo CRC-SC-derived models. Reverse-Phase Protein Microarrays (RPPA) revealed that, albeit CRC-SCs display individual phospho-proteomic profiles, sensitivity of CRC-SCs to UCN-01 relies on the interference with the DNA damage response mediated by Chk1. Combination of LY2603618, a specific Chk1/2 inhibitor, with irinotecan resulted in a significant reduction of CRC-SC growth in vivo, confirming that irinotecan treatment coupled to inhibition of Chk1 represents a potentially effective therapeutic approach for CRC treatment. PMID:27286453

Dietary flavonoid derivatives enhance chemotherapeutic effect by inhibiting the DNA damage response pathway

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kuo, Ching-Ying

Flavonoids are the most common group of polyphenolic compounds and abundant in dietary fruits and vegetables. Diet high in vegetables or dietary flavonoid supplements is associated with reduced mortality rate for patients with breast cancer. Many studies have been proposed for mechanisms linking flavonoids to improving chemotherapy efficacy in many types of cancers, but data on this issue is still limited. Herein, we report on a new mechanism through which dietary flavonoids inhibit DNA damage checkpoints and repair pathways. We found that dietary flavonoids could inhibit Chk1 phosphorylation and decrease clonogenic cell growth once breast cancer cells receive ultraviolet irradiation,more » cisplatin, or etoposide treatment. Since the ATR-Chk1 pathway mainly involves response to DNA replication stress, we propose that flavonoid derivatives reduce the side effect of chemotherapy by improving the sensitivity of cycling cells. Therefore, we propose that increasing intake of common dietary flavonoids is beneficial to breast cancer patients who are receiving DNA-damaging chemotherapy, such as cisplatin or etoposide-based therapy. - Highlights: • First report on inhibition of both DNA damage and repair by dietary flavonoids • Dietary flavonoids inhibit cisplatin- and UV-induced Chk1 phosphorylation. • Flavonoids combined with cisplatin or UV treatment show notable growth inhibition. • Promising treatment proposal for patients who are receiving adjuvant chemotherapy.« less

Reconstitution of RPA-covered single-stranded DNA-activated ATR-Chk1 signaling.

PubMed

Choi, Jun-Hyuk; Lindsey-Boltz, Laura A; Kemp, Michael; Mason, Aaron C; Wold, Marc S; Sancar, Aziz

2010-08-03

ATR kinase is a critical upstream regulator of the checkpoint response to various forms of DNA damage. Previous studies have shown that ATR is recruited via its binding partner ATR-interacting protein (ATRIP) to replication protein A (RPA)-covered single-stranded DNA (RPA-ssDNA) generated at sites of DNA damage where ATR is then activated by TopBP1 to phosphorylate downstream targets including the Chk1 signal transducing kinase. However, this critical feature of the human ATR-initiated DNA damage checkpoint signaling has not been demonstrated in a defined system. Here we describe an in vitro checkpoint system in which RPA-ssDNA and TopBP1 are essential for phosphorylation of Chk1 by the purified ATR-ATRIP complex. Checkpoint defective RPA mutants fail to activate ATR kinase in this system, supporting the conclusion that this system is a faithful representation of the in vivo reaction. Interestingly, we find that an alternative form of RPA (aRPA), which does not support DNA replication, can substitute for the checkpoint function of RPA in vitro, thus revealing a potential role for aRPA in the activation of ATR kinase. We also find that TopBP1 is recruited to RPA-ssDNA in a manner dependent on ATRIP and that the N terminus of TopBP1 is required for efficient recruitment and activation of ATR kinase.

The depletion of ATM inhibits colon cancer proliferation and migration via B56γ2-mediated Chk1/p53/CD44 cascades.

PubMed

Liu, Rui; Tang, Jiajia; Ding, Chaodong; Liang, Weicheng; Zhang, Li; Chen, Tianke; Xiong, Yan; Dai, Xiaowei; Li, Wenfeng; Xu, Yunsheng; Hu, Jin; Lu, Liting; Liao, Wanqin; Lu, Xincheng

2017-04-01

Ataxia-telangiectasia mutated (ATM) protein kinase is a major guardian of genomic stability, and its well-established function in cancer is tumor suppression. Here, we report an oncogenic role of ATM. Using two isogenic sets of human colon cancer cell lines that differed only in their ATM status, we demonstrated that ATM deficiency significantly inhibits cancer cell proliferation, migration, and invasion. The tumor-suppressive function of ATM depletion is not modulated by the compensatory activation of ATR, but it is associated with B56γ2-mediated Chk1/p53/CD44 signaling pathways. Under normal growth conditions, the depletion of ATM prevents B56γ2 ubiquitination and degradation, which activates PP2A-mediated Chk1/p53/p21 signaling pathways, leading to senescence and cell cycle arrest. CD44 was validated as a novel ATM target based on its ability to rescue cell migration and invasion defects in ATM-depleted cells. The activation of p53 induced by ATM depletion suppresses CD44 transcription, thus resulting in epithelial-mesenchymal transition (EMT) and cell migration suppression. Our study suggests that ATM has tumorigenic potential in post-formed colon neoplasia, and it supports ATM as an appealing target for improving cancer therapy. Copyright © 2017 Elsevier B.V. All rights reserved.

Dual inhibition of ATR and ATM potentiates the activity of trabectedin and lurbinectedin by perturbing the DNA damage response and homologous recombination repair.

PubMed

Lima, Michelle; Bouzid, Hana; Soares, Daniele G; Selle, Frédéric; Morel, Claire; Galmarini, Carlos M; Henriques, João A P; Larsen, Annette K; Escargueil, Alexandre E

2016-05-03

Trabectedin (Yondelis®, ecteinascidin-743, ET-743) is a marine-derived natural product approved for treatment of advanced soft tissue sarcoma and relapsed platinum-sensitive ovarian cancer. Lurbinectedin is a novel anticancer agent structurally related to trabectedin. Both ecteinascidins generate DNA double-strand breaks that are processed through homologous recombination repair (HRR), thereby rendering HRR-deficient cells particularly sensitive. We here characterize the DNA damage response (DDR) to trabectedin and lurbinectedin in HeLa cells. Our results show that both compounds activate the ATM/Chk2 (ataxia-telangiectasia mutated/checkpoint kinase 2) and ATR/Chk1 (ATM and RAD3-related/checkpoint kinase 1) pathways. Interestingly, pharmacological inhibition of Chk1/2, ATR or ATM is not accompanied by any significant improvement of the cytotoxic activity of the ecteinascidins while dual inhibition of ATM and ATR strongly potentiates it. Accordingly, concomitant inhibition of both ATR and ATM is an absolute requirement to efficiently block the formation of γ-H2AX, MDC1, BRCA1 and Rad51 foci following exposure to the ecteinascidins. These results are not restricted to HeLa cells, but are shared by cisplatin-sensitive and -resistant ovarian carcinoma cells. Together, our data identify ATR and ATM as central coordinators of the DDR to ecteinascidins and provide a mechanistic rationale for combining these compounds with ATR and ATM inhibitors.

Combining Chk1/2 Inhibition with Cetuximab and Radiation Enhances In Vitro and In Vivo Cytotoxicity in Head and Neck Squamous Cell Carcinoma

PubMed Central

Zeng, Ling; Beggs, Reena R.; Cooper, Tiffiny S.; N.Weaver, Alice; S.Yang, Eddy

2017-01-01

EGFR inhibition and radiotherapy are potent inducers of DNA damage. Checkpoint kinases 1 and 2 (Chk1/2) are critical regulators of the DNA-damage response, controlling cell-cycle checkpoints that may permit recovery from therapy-associated genomic stress. We hypothesized that Chk1/2 inhibition (CHKi) with prexasertib may enhance cytotoxicity from EGFR inhibition plus radiotherapy in head and neck squamous cell carcinoma (HNSCC). In this study, we found that the addition of CHKi to the EGFR inhibitor cetuximab with and without radiotherapy significantly decreased cell proliferation and survival fraction in human papillomavirus virus (HPV)-positive and HPV-negative HNSCC cell lines. Reduced proliferation was accompanied by decreased checkpoint activation, induced S-phase accumulation, persistent DNA damage, and increased caspase cleavage and apoptosis. Importantly, a significant tumor growth delay was observed in vivo in both HPV-positive and HPV-negative cell line xenografts receiving triple combination therapy with CHKi, cetuximab, and radiotherapy without a concomitant increase in toxicity as assessed by mouse body weight. Taken together, the combination of CHKi with cetuximab plus irradiation displayed significant antitumor effects in HNSCCs both in vitro and in vivo, suggesting that this combination therapy may increase clinical benefit. A clinical trial to test this treatment for patients with head and neck cancer is currently ongoing (NCT02555644). PMID:28138028

Maternal nutritional status during pregnancy and surma use determine cord lead levels in Karachi, Pakistan

DOE Office of Scientific and Technical Information (OSTI.GOV)

Janjua, Naveed Zafar; Department of Community Health Sciences, Aga Khan University, Karachi; Delzell, Elizabeth

Objectives: To estimate the umbilical cord blood lead levels (BLLs) of Pakistani neonates and to identify determinants for umbilical BLLs. Methods: We conducted a cross-sectional study of mothers and infants at one of the two obstetric units of two tertiary care hospitals in Karachi during January-August 2005. Information from 540 mothers selected randomly from those registered for delivery was obtained about their pregnancy, diet, and current and past lead exposures. We collected umbilical cord blood for lead levels analyzed using graphite furnace atomic absorption spectrophotometry. We computed geometric and arithmetic means. We performed multiple linear regression analysis to identify factorsmore » associated with log-transformed umbilical cord BLLs. We also performed logistic regression analysis to identify determinants of high lead cord BLLs ({>=}10 {mu}g/dl). Results: The geometric mean cord BLL of the neonates was 9.6 {mu}g/dl; arithmetic mean (S.D.) was 10.8 {mu}g/dl (5.7) with a median of 9.7 {mu}g/dl and a range of 1.8-48.9 {mu}g/dl. Women who reported intake of less than 58.5 mg of elemental iron supplement per day during pregnancy had cord BLL of 10.0 {mu}g/dl; in comparison those women who had higher iron intake had lower cord BLL (8.4 {mu}g/dl). Those who used surma (an eye cosmetic) daily had higher cord BLL (11.5 {mu}g/dl) as compared to those who used it less frequently (9.4 {mu}g/dl). In multivariable linear regression model, higher iron intake, owning a car, and being in 2nd quartile of mid-arm circumference were associated with low lead levels while father's occupation in lead-based industry was associated with significantly higher umbilical cord BLLs. There was interaction of daily surma use and ethnicity. Geometric mean BLLs were varied among surma users by ethnicity. Conclusions: Umbilical cord BLLs are high in Karachi, Pakistan, in comparison to those in developed countries such as United States. Measures are needed to reduce fetal lead exposure to prevent adverse affect on neurocognitive development. Association of low iron (below RDA of 60 mg per day) with high umbilical cord has implications for strengthening iron supplement intake during pregnancy. Umbilical cord BLLs differed among surma users by ethnicity.« less

On the Form of a Systemic Grammar

ERIC Educational Resources Information Center

McCord, Michael C.

1975-01-01

This paper concerns the theory of systemic grammar developed by Halliday, Hudson and others. It suggests modifications of Hudson's generative version, and the model presented resembles transformational grammar. (CHK)

Use of liquid nitrogen and albendazole in successfully treating cutaneous larva migrans.

PubMed

Kapadia, Naseema; Borhany, Tasneem; Farooqui, Maria

2013-05-01

To determine the efficacy of combination treatment of Albendazole along with liquid nitrogen in cutaneous larva migrans. Quasi-experimental study. Abbasi Shaheed Hospital and The Aga Khan Hospital, Karachi, from December 2008 to December 2010. Eighteen cases of cutaneous larva migrans were collected and divided into two groups. Group-A was administered oral Albendazole 400 mg once per day along with topical steroid and oral cetrizine 10 mg once at night for 7 days. Group-B also received oral Albendazole 400 mg once per day along with cetrizine 10 mg once at night but they also received single application of liquid nitrogen to freeze the larva. It was found that in Group-A only 2 out of 9 (22%) showed improvement whereas 78% had to be given liquid nitrogen cryotherapy 3 - 7 days after Albendazole to prevent migration of larva. In Group-B, the improvement was 100% and all 9 patients were successfully treated. Use of liquid nitrogen along with oral anti-helminths is very effective in treating cutaneous larva migrans than Albendazole alone.

Repeat cranial tomography in patients with mild head injury and stable neurological examination ---- a perspective from a developing country.

PubMed

Nasir, Sadaf; Hussain, Manzar

2011-01-01

To determine the frequency of altered findings on repeat cranial tomography (CT) in patients with mild head injury along with stable neurological examination at tertiary care hospital. Cross-sectional study was done in the Department of Radiology, Liaquat National Hospital, Karachi from January 2008 to September 2010. All patients with mild head injury in terms of Glasgow Coma Scale (GCS) who underwent repeat scan without clinical or neurological deterioration in the emergency department of a tertiary care centre were included. The collected data were accordingly entered and analyzed by the principal investigator using Statistical Package for Social Sciences (SPSS) version 16.0. In all 275 patients, only 17 (6%) of the patients were found worseing on repeat CT, 120 (43.63%) scans improved, 138 (50.18%) unchanged and 17 (6.18%) worsened. None of these patients showed signs of clinical deterioration. Our results suggest that for patients with mild head injury and stable neurological examination, only 6% of them show deterioration on repeat CT, especially when patients'GCS is below 13.

Apprehensions and problems after laryngectomy: Patients' perspective.

PubMed

Hirani, Ismail; Siddiqui, Atif Hafeez; Muhammad Khyani, Iqbal Abdul

2015-11-01

To evaluate the apprehensions, social, sexual and financial problems in patients with advanced laryngeal cancer after total laryngectomy and the impact of attending laryngeal club on these problems. The analytical study was conducted at the Dow Medical College and Civil Hospital Karachi from January 1996 to December 2011. Patients with total laryngectomy, operated for advanced laryngeal cancer at various centres of Sindh and Balochistan, attending Laryngeal Club of Pakistan, situated at Civil Hospital Karachi, were included. All the patients were evaluated through a questionnaire covering their apprehensions regarding social, sexual and financial impact on their lives after total laryngectomy. Data was analysed using SPSS 16. Of the 125 patients, 120(96%) were males, and 5(4%) were females; all housewives. The overall mean age was 54.8±0.5 years (range: 31-65 years). Further, 92(74%) participants were worried about financial uncertainty, while 84(67%) had regrets over loss of their voice; patients worried about losing family support and facing social rejection were 23(18%) and 15(12%) respectively. Only 7(5%) patients feared losing sexual relationship with their spouse. All these apprehensions were subdued after attending the Laryngeal Club of Pakistan. Severe financial impact was faced by 55(44%) patients due to loss of job, while 05(4%) had moderate impact due to change of job with lower income and 60(48%) patients had no financial problem. A good 102(82%) participants thought the support from their friends and family was upto their expectations; 98(78%) enjoyed satisfactory sex life although with reduced frequency of 1 to 2 intercourses per month; 21(17%) were having the frequency of 3-10 per month; and 3(2%) had more than 10 per month. Only 16(13%) patients were not involved in sexual relations with their spouses due to various reasons. Majority of laryngectomised patients expressed apprehensions and showed some social problems after laryngectomy, especially in the initial phase which improved either with passage of time or after attending Laryngectomy Club. The main problem was financial constraints; majority had good friends and family support and enjoyed satisfactory sexual relationship with their spouse.

Myths and fallacies about male contraceptive methods: a qualitative study amongst married youth in slums of Karachi, Pakistan.

PubMed

Nishtar, Noureen Aleem; Sami, Neelofar; Faruqi, Anum; Khowaja, Shaneela; Ul-Hasnain, Farid

2012-12-04

Pakistan presently has one of the largest cohorts of young people in its history, with around 36 million people between the ages of 15 and 24 years. One of the main reasons for high population growth in Pakistan is almost stagnant contraceptive prevalence rate of 30% nationally and 17.4% amongst youth. The study was conducted to explore the perceptions regarding myths and fallacies related to male contraceptive methods among married youth aged 18-24 year in Karachi, Pakistan. Qualitative exploratory study design was adopted and a total of eight Focus Group Discussions (FGDs) were conducted. Study was conducted in two Union Councils of Korangi Town in the squatter settlement of Karachi, Pakistan from July to September 2010. Thematic analysis was done manually. General, physical, sexual, psychological, socio-cultural and religious were the common categories which lead to myths and fallacies related to condoms use and vasectomy among the married youth. The foremost myth amongst male and female youth was that use of both condoms and vasectomy cause impotence in males. Additionally, condoms were thought to cause infections, backache and headache in males. Some youth of the area think that vasectomy is meant for prisoners only. In conclusion our findings suggest that the potential reasons behind low use of male contraceptive methods among youth of squatter settlement of Karachi were myths and fallacies about male contraceptive methods. There are some important policy implications like counseling of the couple through peers and well trained family planning service providers to address these myths and misconceptions from the minds of youth.

Heterogeneity of characteristics, structure, and dynamics of male and hijra sex workers in selected cities of Pakistan.

PubMed

Thompson, Laura H; Salim, Momina; Baloch, Chaker Riaz; Musa, Nighat; Reza, Tahira; Dar, Nosheen; Arian, Shahzad; Blanchard, James F; Emmanuel, Faran

2013-09-01

We sought to describe the characteristics and operational dynamics of male sex workers (MSW) and hijra sex workers (HSWs) in 11 cities across Pakistan in 2011. We report descriptive statistics of self-reported sexual behaviour data from cross-sectional mapping and biological and behavioural surveys conducted among 1431 MSWs and 1415 HSWs in four cities across Pakistan in 2011. While Karachi had the largest numbers of MSWs and HSWs, Quetta had the largest relative population sizes, with 3.6 MSWs per 1000 male adults and 3.3 HSWs per 1000 male adults. There was considerable variability in the proportion of HSWs who operate through deras, ranging from 2.2% in Peshawar to 62.7% in Karachi. The number of HSWs per guru varies by city, from 1.5 in Quetta to 16.5 HSWs per guru in Karachi. Among HSWs, the use of mobile phones for solicitation ranged from 37.6% in Quetta to 83% in Peshawar and among MSWs the use of mobile phones ranged from 27% in Karachi to 52% in Quetta. In Quetta, a large proportion of HSWs (41%) find clients through gurus. Client volume tended to be higher among HSWs and among both MSWs and HSWs in Quetta and Peshawar. Condom use with clients was most consistent in Quetta, with 31% of MSWs and 41% of HSWs reporting always using condoms with clients. Peshawar had the greatest proportion reporting never using condoms. There is considerable geographic heterogeneity in the characteristics and operational dynamics of MSWs and HSWs across Pakistan.

Myths and Fallacies about Male Contraceptive Methods: A Qualitative Study amongst Married Youth in Slums of Karachi, Pakistan

PubMed Central

Nishtar, Noureen; Sami, Neelofar; Faruqi, Anum; Khowaja, Shaneela; Farid-Ul-Hasnain

2013-01-01

Pakistan presently has one of the largest cohorts of young people in its history, with around 36 million people between the ages of 15 and 24 years. One of the main reasons for high population growth in Pakistan is almost stagnant contraceptive prevalence rate of 30% nationally and 17.4% amongst youth. The study was conducted to explore the perceptions regarding myths and fallacies related to male contraceptive methods among married youth aged 18-24 year in Karachi, Pakistan. Qualitative exploratory study design was adopted and a total of eight Focus Group Discussions (FGDs) were conducted. Study was conducted in two Union Councils of Korangi Town in the squatter settlement of Karachi, Pakistan from July to September 2010. Thematic analysis was done manually. General, physical, sexual, psychological, socio-cultural and religious were the common categories which lead to myths and fallacies related to condoms use and vasectomy among the married youth. The foremost myth amongst male and female youth was that use of both condoms and vasectomy cause impotence in males. Additionally, condoms were thought to cause infections, backache and headache in males. Some youth of the area think that vasectomy is meant for prisoners only. In conclusion our findings suggest that the potential reasons behind low use of male contraceptive methods among youth of squatter settlement of Karachi were myths and fallacies about male contraceptive methods. There are some important policy implications like counseling of the couple through peers and well trained family planning service providers to address these myths and misconceptions from the minds of youth. PMID:23445697

Knowledge, attitude and practice of mothers regarding their own and children's dental health--a tertiary care hospital based study.

PubMed

Farid, Huma; Khan, Farhan Raza; Aman, Nadia

2013-01-01

Mothers play a basic role in the dental health of children. They decide whether their children need dental treatment or not. The aims of this study were to assess mothers' knowledge and practices regarding children's dental health and to determine association of mothers own attitude and their attitude towards children's dental health. A cross sectional study was conducted in the Aga Khan University Hospital (AKUH), Karachi, Pakistan in which 207 mothers completed a self-administered structured questionnaire. Inclusion criteria were respondents having children between 2 and 5 years of age and exclusion criteria were respondents having physical or mentally handicapped children. SPSS-16 was used for data analysis. Chi Square test was used to determine association between maternal own dental attitude and their attitude and knowledge about children dental health with p < or = 0.05 as statistically significant. Majority of the mothers used to visit dentists for themselves in the case of problems and they thought the same for their children (p < 0.001). A statistically significant association also existed between mothers and children tooth brushing frequency (p < 0.001). Mothers visiting Aga Khan University Hospital, lack sufficient knowledge regarding timings of the children's first dental visit and the importance of limiting frequency of in-between meals snacks consumed by their children.

Cultural Contrasts--A Broader Concept

ERIC Educational Resources Information Center

Hahn, Sidney L.

1975-01-01

This article describes various attempts at teaching and learning cross-cultural understanding through workshops; preparing instructional materials, including magazine advertisements, to be analyzed; and interdisciplinary lectures and programs. Aspects of German culture are emphasized. (CHK)

Bibliographical Outline for a Course in Humanism and Reformation

ERIC Educational Resources Information Center

Helmetag, Charles H.

1975-01-01

A bibliography for a course in humanism and the Reformation is divided into sections on a syllabus, general bibliography and specialized bibliography covering important figures and issues of the period. (CHK)

Gender differences in nonfatal suicidal behavior in Pakistan: significance of sociocultural factors.

PubMed

Khan, M M; Reza, H

1998-01-01

Suicidal behavior is an understudied subject in Pakistan. A variety of social, legal, and religious factors make reporting and data collection on suicide and nonfatal suicidal behavior difficult. To study the problem, a retrospective case-note analysis was carried out in which the sociodemographic and clinical characteristics of 262 female and 185 male suicidal individuals admitted to a university hospital in Karachi, Pakistan, are compared. Three quarters of the suicidal persons were under the age of 30 years. Compared to men, women were younger and more often married. Both women and men tended to use self-poisoning with benzodiazepines, but more women used organophosphate insecticides. In Pakistani society, legal, social, and economic discrimination predisposes women to psychological distress and subsequent suicidal behavior. The study highlights the need for culture-specific research on suicidal behavior in Pakistan.

A ruthenium polypyridyl intercalator stalls DNA replication forks, radiosensitizes human cancer cells and is enhanced by Chk1 inhibition

NASA Astrophysics Data System (ADS)

Gill, Martin R.; Harun, Siti Norain; Halder, Swagata; Boghozian, Ramon A.; Ramadan, Kristijan; Ahmad, Haslina; Vallis, Katherine A.

2016-08-01

Ruthenium(II) polypyridyl complexes can intercalate DNA with high affinity and prevent cell proliferation; however, the direct impact of ruthenium-based intercalation on cellular DNA replication remains unknown. Here we show the multi-intercalator [Ru(dppz)2(PIP)]2+ (dppz = dipyridophenazine, PIP = 2-(phenyl)imidazo[4,5-f][1,10]phenanthroline) immediately stalls replication fork progression in HeLa human cervical cancer cells. In response to this replication blockade, the DNA damage response (DDR) cell signalling network is activated, with checkpoint kinase 1 (Chk1) activation indicating prolonged replication-associated DNA damage, and cell proliferation is inhibited by G1-S cell-cycle arrest. Co-incubation with a Chk1 inhibitor achieves synergistic apoptosis in cancer cells, with a significant increase in phospho(Ser139) histone H2AX (γ-H2AX) levels and foci indicating increased conversion of stalled replication forks to double-strand breaks (DSBs). Normal human epithelial cells remain unaffected by this concurrent treatment. Furthermore, pre-treatment of HeLa cells with [Ru(dppz)2(PIP)]2+ before external beam ionising radiation results in a supra-additive decrease in cell survival accompanied by increased γ-H2AX expression, indicating the compound functions as a radiosensitizer. Together, these results indicate ruthenium-based intercalation can block replication fork progression and demonstrate how these DNA-binding agents may be combined with DDR inhibitors or ionising radiation to achieve more efficient cancer cell killing.

Jaceosidin, isolated from dietary mugwort (Artemisia princeps), induces G2/M cell cycle arrest by inactivating cdc25C-cdc2 via ATM-Chk1/2 activation.

PubMed

Lee, Jong-Gyu; Kim, Ji-Hyun; Ahn, Ji-Hye; Lee, Kyung-Tae; Baek, Nam-In; Choi, Jung-Hye

2013-05-01

Jaceosidin, a flavonoid derived from Artemisia princeps (Japanese mugwort), has been shown to inhibit the growth of several human cancer cells, However, the exact mechanism for the cytotoxic effect of jaceosidin is not completely understood. In this study, we investigated the molecular mechanism involved in the antiproliferative effect of jaceosidin in human endometrial cancer cells. We demonstrated that jaceosidin is a more potent inhibitor of cell growth than cisplatin in human endometrial cancer cells. In contrast, jaceosidin-induced cytotoxicity in normal endometrial cells was lower than that observed for cisplatin. Jaceosidin induced G2/M phase cell cycle arrest and modulated the levels of cyclin B and p-Cdc2 in Hec1A cells. Knockdown of p21 using specific siRNAs partially abrogated jaceosidin-induced cell growth inhibition. Additional mechanistic studies revealed that jaceosidin treatment resulted in an increase in phosphorylation of Cdc25C and ATM-Chk1/2. Ku55933, an ATM inhibitor, reversed jaceosidin-induced cell growth inhibition, in part. Moreover, jaceosidin treatment resulted in phosphorylation of ERK, and pretreatment with the ERK inhibitor, PD98059, attenuated cell growth inhibition by jaceosidin. These data suggest that jaceosidin, isolated from Japanese mugwort, modulates the ERK/ATM/Chk1/2 pathway, leading to inactivation of the Cdc2-cyclin B1 complex, followed by G2/M cell cycle arrest in endometrial cancer cells. Copyright © 2012 Elsevier Ltd. All rights reserved.

The Protective Role of Selenium in AFB1-Induced Tissue Damage and Cell Cycle Arrest in Chicken's Bursa of Fabricius.

PubMed

Hu, Ping; Zuo, Zhicai; Wang, Fengyuan; Peng, Xi; Guan, Ke; Li, Hang; Fang, Jing; Cui, Hengmin; Su, Gang; Ouyang, Ping; Zhou, Yi

2018-03-06

Aflatoxin B 1 (AFB 1 ) is a naturally occurring secondary metabolites of Aspergillus flavus and Aspergillus parasiticus, and is the most toxic form of aflatoxins. Selenium (Se) with antioxidant and detoxification functions is one of the essential trace elements for human beings and animals. This study aims to evaluate the protective effects of Se on AFB 1 -induced tissue damage and cell cycle arrest in bursa of Fabricius (BF) of chickens. The results showed that a dietary supplement of 0.4 mg·kg -1 Se alleviated the histological lesions induced by AFB 1 , as demonstrated by decreasing vacuoles and nuclear debris, and relieving oxidative stress. Furthermore, flow cytometry studies showed that a Se supplement protected AFB 1 -induced G 2 M phase arrest at 7 days and G 0 G 1 phase arrest at 14 and 21 days. Moreover, the mRNA expression results of ATM, Chk2, p53, p21, cdc25, PCNA, cyclin D 1 , cyclin E 1 , cyclin B 3 , CDK6, CDK2, and cdc2 indicated that Se supplement could restore these parameters to be close to those in the control group. It is concluded that a dietary supplement of 0.4 mg kg -1 Se could diminish AFB 1 -induced immune toxicity in chicken's BF by alleviating oxidative damage and cell cycle arrest through an ATM-Chk2-cdc25 route and the ATM-Chk2-p21 pathway.

A ruthenium polypyridyl intercalator stalls DNA replication forks, radiosensitizes human cancer cells and is enhanced by Chk1 inhibition.

PubMed

Gill, Martin R; Harun, Siti Norain; Halder, Swagata; Boghozian, Ramon A; Ramadan, Kristijan; Ahmad, Haslina; Vallis, Katherine A

2016-08-25

Ruthenium(II) polypyridyl complexes can intercalate DNA with high affinity and prevent cell proliferation; however, the direct impact of ruthenium-based intercalation on cellular DNA replication remains unknown. Here we show the multi-intercalator [Ru(dppz)2(PIP)](2+) (dppz = dipyridophenazine, PIP = 2-(phenyl)imidazo[4,5-f][1,10]phenanthroline) immediately stalls replication fork progression in HeLa human cervical cancer cells. In response to this replication blockade, the DNA damage response (DDR) cell signalling network is activated, with checkpoint kinase 1 (Chk1) activation indicating prolonged replication-associated DNA damage, and cell proliferation is inhibited by G1-S cell-cycle arrest. Co-incubation with a Chk1 inhibitor achieves synergistic apoptosis in cancer cells, with a significant increase in phospho(Ser139) histone H2AX (γ-H2AX) levels and foci indicating increased conversion of stalled replication forks to double-strand breaks (DSBs). Normal human epithelial cells remain unaffected by this concurrent treatment. Furthermore, pre-treatment of HeLa cells with [Ru(dppz)2(PIP)](2+) before external beam ionising radiation results in a supra-additive decrease in cell survival accompanied by increased γ-H2AX expression, indicating the compound functions as a radiosensitizer. Together, these results indicate ruthenium-based intercalation can block replication fork progression and demonstrate how these DNA-binding agents may be combined with DDR inhibitors or ionising radiation to achieve more efficient cancer cell killing.

Msc1 acts through histone H2A.Z to promote chromosome stability in Schizosaccharomyces pombe.

PubMed

Ahmed, Shakil; Dul, Barbara; Qiu, Xinxing; Walworth, Nancy C

2007-11-01

As a central component of the DNA damage checkpoint pathway, the conserved protein kinase Chk1 mediates cell cycle progression when DNA damage is generated. Msc1 was identified as a multicopy suppressor capable of facilitating survival in response to DNA damage of cells mutant for chk1. We demonstrate that loss of msc1 function results in an increased rate of chromosome loss and that an msc1 null allele exhibits genetic interactions with mutants in key kinetochore components. Multicopy expression of msc1 robustly suppresses a temperature-sensitive mutant (cnp1-1) in the centromere-specific histone H3 variant CENP-A, and localization of CENP-A to the centromere is compromised in msc1 null cells. We present several lines of evidence to suggest that Msc1 carries out its function through the histone H2A variant H2A.Z, encoded by pht1 in fission yeast. Like an msc1 mutant, a pht1 mutant also exhibits chromosome instability and genetic interactions with kinetochore mutants. Suppression of cnp1-1 by multicopy msc1 requires pht1. Likewise, suppression of the DNA damage sensitivity of a chk1 mutant by multicopy msc1 also requires pht1. We present the first genetic evidence that histone H2A.Z may participate in centromere function in fission yeast and propose that Msc1 acts through H2A.Z to promote chromosome stability and cell survival following DNA damage.

Msc1 Acts Through Histone H2A.Z to Promote Chromosome Stability in Schizosaccharomyces pombe

PubMed Central

Ahmed, Shakil; Dul, Barbara; Qiu, Xinxing; Walworth, Nancy C.

2007-01-01

As a central component of the DNA damage checkpoint pathway, the conserved protein kinase Chk1 mediates cell cycle progression when DNA damage is generated. Msc1 was identified as a multicopy suppressor capable of facilitating survival in response to DNA damage of cells mutant for chk1. We demonstrate that loss of msc1 function results in an increased rate of chromosome loss and that an msc1 null allele exhibits genetic interactions with mutants in key kinetochore components. Multicopy expression of msc1 robustly suppresses a temperature-sensitive mutant (cnp1-1) in the centromere-specific histone H3 variant CENP-A, and localization of CENP-A to the centromere is compromised in msc1 null cells. We present several lines of evidence to suggest that Msc1 carries out its function through the histone H2A variant H2A.Z, encoded by pht1 in fission yeast. Like an msc1 mutant, a pht1 mutant also exhibits chromosome instability and genetic interactions with kinetochore mutants. Suppression of cnp1-1 by multicopy msc1 requires pht1. Likewise, suppression of the DNA damage sensitivity of a chk1 mutant by multicopy msc1 also requires pht1. We present the first genetic evidence that histone H2A.Z may participate in centromere function in fission yeast and propose that Msc1 acts through H2A.Z to promote chromosome stability and cell survival following DNA damage. PMID:17947424

53BP1 loss suppresses the radiosensitizing effect of icotinib hydrochloride in colorectal cancer cells.

PubMed

Huang, Ai; Yao, Jing; Liu, Tao; Lin, Zhenyu; Zhang, Sheng; Zhang, Tao; Ma, Hong

2018-04-01

This study aimed to investigate the influence of the expression of P53-binding protein 1 (53BP1), a key component in DNA damage repair pathways, on the radiosensitizing effect of icotinib hydrochloride in colorectal cancer and to elucidate the mechanisms underlying this influence. Real-time RT-PCR and Western blotting were performed to verify the gene-knockout effect of 53BP1 small hairpin RNA (ShRNA), and colony formation assay was employed to investigate the influence of 53BP1 downregulation on the radiosensitizing effect of icotinib hydrochloride in HCT116 cells. Cell apoptosis, cell cycle distributions, and histone H2AX (γ-H2AX) fluorescence foci after 53BP1 knockdown were evaluated. Relative protein expression in the ataxia telangiectasia mutated kinase (ATM)-checkpoint kinase-2 (CHK2)-P53 pathway was measured by Western blot analysis to unravel the molecular mechanisms linking the pathway to the above phenomena. Icotinib hydrochloride increased the radiosensitivity of HCT116 cells; however, this effect was suppressed by the downregulation of 53BP1 expression, a change that inhibited cell apoptosis, increased the percentage of HCT116 cells arrested in S-phase and inhibited the protein expression of key molecules in the ATM-CHK2-P53 apoptotic pathway. Our studies confirmed that the loss of 53BP1 serves as a negative regulator of the radiosensitizing effect of icotinib in part by suppressing the ATM-CHK2-P53 apoptotic pathway.

Combining Chk1/2 Inhibition with Cetuximab and Radiation Enhances In Vitro and In Vivo Cytotoxicity in Head and Neck Squamous Cell Carcinoma.

PubMed

Zeng, Ling; Beggs, Reena R; Cooper, Tiffiny S; Weaver, Alice N; Yang, Eddy S

2017-04-01

EGFR inhibition and radiotherapy are potent inducers of DNA damage. Checkpoint kinases 1 and 2 (Chk1/2) are critical regulators of the DNA-damage response, controlling cell-cycle checkpoints that may permit recovery from therapy-associated genomic stress. We hypothesized that Chk1/2 inhibition (CHKi) with prexasertib may enhance cytotoxicity from EGFR inhibition plus radiotherapy in head and neck squamous cell carcinoma (HNSCC). In this study, we found that the addition of CHKi to the EGFR inhibitor cetuximab with and without radiotherapy significantly decreased cell proliferation and survival fraction in human papillomavirus virus (HPV)-positive and HPV-negative HNSCC cell lines. Reduced proliferation was accompanied by decreased checkpoint activation, induced S-phase accumulation, persistent DNA damage, and increased caspase cleavage and apoptosis. Importantly, a significant tumor growth delay was observed in vivo in both HPV-positive and HPV-negative cell line xenografts receiving triple combination therapy with CHKi, cetuximab, and radiotherapy without a concomitant increase in toxicity as assessed by mouse body weight. Taken together, the combination of CHKi with cetuximab plus irradiation displayed significant antitumor effects in HNSCCs both in vitro and in vivo , suggesting that this combination therapy may increase clinical benefit. A clinical trial to test this treatment for patients with head and neck cancer is currently ongoing (NCT02555644). Mol Cancer Ther; 16(4); 591-600. ©2017 AACR . ©2017 American Association for Cancer Research.

Circumvention of Mcl-1-dependent drug resistance by simultaneous Chk1 and MEK1/2 inhibition in human multiple myeloma cells.

PubMed

Pei, Xin-Yan; Dai, Yun; Felthousen, Jessica; Chen, Shuang; Takabatake, Yukie; Zhou, Liang; Youssefian, Leena E; Sanderson, Michael W; Bodie, Wesley W; Kramer, Lora B; Orlowski, Robert Z; Grant, Steven

2014-01-01

The anti-apoptotic protein Mcl-1 plays a major role in multiple myeloma (MM) cell survival as well as bortezomib- and microenvironmental forms of drug resistance in this disease. Consequently, there is a critical need for strategies capable of targeting Mcl-1-dependent drug resistance in MM. The present results indicate that a regimen combining Chk1 with MEK1/2 inhibitors effectively kills cells displaying multiple forms of drug resistance stemming from Mcl-1 up-regulation in association with direct transcriptional Mcl-1 down-regulation and indirect disabling of Mcl-1 anti-apoptotic function through Bim up-regulation and increased Bim/Mcl-1 binding. These actions release Bak from Mcl-1, accompanied by Bak/Bax activation. Analogous events were observed in both drug-naïve and acquired bortezomib-resistant MM cells displaying increased Mcl-1 but diminished Bim expression, or cells ectopically expressing Mcl-1. Moreover, concomitant Chk1 and MEK1/2 inhibition blocked Mcl-1 up-regulation induced by IL-6/IGF-1 or co-culture with stromal cells, effectively overcoming microenvironment-related drug resistance. Finally, this regimen down-regulated Mcl-1 and robustly killed primary CD138+ MM cells, but not normal hematopoietic cells. Together, these findings provide novel evidence that this targeted combination strategy could be effective in the setting of multiple forms of Mcl-1-related drug resistance in MM.

Circumvention of Mcl-1-Dependent Drug Resistance by Simultaneous Chk1 and MEK1/2 Inhibition in Human Multiple Myeloma Cells

PubMed Central

Pei, Xin-Yan; Dai, Yun; Felthousen, Jessica; Chen, Shuang; Takabatake, Yukie; Zhou, Liang; Youssefian, Leena E.; Sanderson, Michael W.; Bodie, Wesley W.; Kramer, Lora B.; Orlowski, Robert Z.; Grant, Steven

2014-01-01

The anti-apoptotic protein Mcl-1 plays a major role in multiple myeloma (MM) cell survival as well as bortezomib- and microenvironmental forms of drug resistance in this disease. Consequently, there is a critical need for strategies capable of targeting Mcl-1-dependent drug resistance in MM. The present results indicate that a regimen combining Chk1 with MEK1/2 inhibitors effectively kills cells displaying multiple forms of drug resistance stemming from Mcl-1 up-regulation in association with direct transcriptional Mcl-1 down-regulation and indirect disabling of Mcl-1 anti-apoptotic function through Bim up-regulation and increased Bim/Mcl-1 binding. These actions release Bak from Mcl-1, accompanied by Bak/Bax activation. Analogous events were observed in both drug-naïve and acquired bortezomib-resistant MM cells displaying increased Mcl-1 but diminished Bim expression, or cells ectopically expressing Mcl-1. Moreover, concomitant Chk1 and MEK1/2 inhibition blocked Mcl-1 up-regulation induced by IL-6/IGF-1 or co-culture with stromal cells, effectively overcoming microenvironment-related drug resistance. Finally, this regimen down-regulated Mcl-1 and robustly killed primary CD138+ MM cells, but not normal hematopoietic cells. Together, these findings provide novel evidence that this targeted combination strategy could be effective in the setting of multiple forms of Mcl-1-related drug resistance in MM. PMID:24594907

Lymphoma cases referred to the radiation oncology service of a tertiary referral university hospital in Karachi, Pakistan: a retrospective study.

PubMed

Abbasi, Ahmed Nadeem; Zahid, Sumaiya; Karsan, Farrok; Ali, Nasir; Bhurgri, Yasmin

2010-01-01

Radiation therapy is an important component of curative therapy for Lymphoma [Hodgkin's disease (HD) and non Hodgkin's Lymphoma (NHL)]. The current study was conducted to give us an overview of lymphoma patients presenting to a tertiary care hospital for complementary adjuvant RT. Data of lymphoma patients who underwent radiotherapy during February 2006 till August 2009 at the department of radiation oncology, Aga Khan University, Hospital, Karachi was retrieved from the medical records and analyzed using SPSS (version 16.0). A total of 1,678 cancer patients were registered, 75 (0.45%) were lymphoma patients (25.3% HD; 74.7% NHL). HD and NHL were both seen predominantly in males, with a male:female ratio of 2 and 3 respectively. Nodal HD comprised 94.7% and nodal NHL comprised 41.1%. Extranodal NHL (EN-NHL) comprised 53.6% whereas 5.4% cases had both nodal and EN-NHL; 6.7% of EN-NHL were primary CNS lymphomas. Stages of presentation for HD were IIA (52.6%), 1A (21.1%), IIB (10.5%) and IB, IIIB and IVA collectively 15.9%. The ages of HD patients ranged from 11 to 54 years (median 23.5 years 13.2 SD). Response to therapy for HD was 52.6% complete remission, 36.8% partial response, and 5.3% each with stable and progressive disease. Almost all patients (94.7%) received radical treatment with radiation doses (between 1950 cG to 5404 cGy) with a median of 40 Grays.Stages at presentation for NHL were II (23.2%), IV (21.4%) and IE (17.9%); I, IIE, and III were found to be 12.5 %. NHL patients ranged from 15 to 88 years. It was more commonly observed amongst the elderly with 25% patients diagnosed in the fifth decade of life; 50% patients aged at or above 50 years, 41.1% belonged to the 25-49 years age group and 8.9% below 25 years of age. Majority of the cases were diffuse NHL (82.1%), follicular NHL (7.1%), Primary CNS unclassified type (8.9%), and unclassified other than CNS variety (1.8%). Response to chemotherapy for NHL was 51.8% complete remission, 25.9% progressive disease, 20.4% partial response. Forty (71.4%) patients with NHL received radical treatment with radiation doses between 2340 cG to 6600 cGy; 28.6% received palliative RT. Radiation therapy though important for curative lymphoma therapy, is relatively underutilized in our population, despite encouraging outcomes.

Contrasting aerosol optical and radiative properties between dust and urban haze episodes in megacities of Pakistan

NASA Astrophysics Data System (ADS)

Iftikhar, Muhammad; Alam, Khan; Sorooshian, Armin; Syed, Waqar Adil; Bibi, Samina; Bibi, Humera

2018-01-01

Satellite and ground based remote sensors provide vital information about aerosol optical and radiative properties. Analysis of aerosol optical and radiative properties during heavy aerosol loading events in Pakistan are limited and, therefore, require in-depth examination. This work examines aerosol properties and radiative forcing during Dust Episodes (DE) and Haze Episodes (HE) between 2010 and 2014 over mega cities of Pakistan (Karachi and Lahore). Episodes having the daily averaged values of Aerosol Optical Depth (AOD) exceeding 1 were selected. DE were associated with high AOD and low Ångström Exponent (AE) over Karachi and Lahore while high AOD and high AE values were associated with HE over Lahore. Aerosol volume size distributions (AVSD) exhibited a bimodal lognormal distribution with a noticeable coarse mode peak at a radius of 2.24 μm during DE, whereas a fine mode peak was prominent at a radius 0.25 μm during HE. The results reveal distinct differences between HE and DE for spectral profiles of several parameters including Single Scattering Albedo (SSA), ASYmmetry parameter (ASY), and the real and imaginary components of refractive index (RRI and IRI). The AOD-AE correlation revealed that dust was the dominant aerosol type during DE and that biomass burning and urban/industrial aerosol types were pronounced during HE. Aerosol radiative forcing (ARF) was estimated using the Santa Barbra DISORT Atmospheric Radiative Transfer (SBDART) model. Calculations revealed a negative ARF at the Top Of the Atmosphere (ARFTOA) and at the Bottom Of the Atmosphere (ARFBOA), with positive ARF within the Atmosphere (ARFATM) during both DE and HE over Karachi and Lahore. Furthermore, estimations of ARFATM by SBDART were shown to be in good agreement with values derived from AERONET data for DE and HE over Karachi and Lahore.

Quality of drug stores: Storage practices & Regulatory compliance in Karachi, Pakistan

PubMed Central

Shah, Syed Shaukat Ali Muttaqi; Naqvi, Baqar Shyum; Fatima, Mashhad; Khaliq, Asif; Sheikh, Abdul Latif; Baqar, Muhammad

2016-01-01

Objective: To assess and evaluate the drug storage quality and regulatory compliance among privately operated drug stores of Karachi Pakistan. Methods: A cross-sectional survey of drug stores located in Karachi was conducted from May to December 2013. A total of 1003 drug stores that were involved in the sales, purchase and dispensing of pharmaceutical products were approached by non-probability purposive sampling technique, and the information was collected using a close ended, structured questionnaire. Results: Out of 1003 drug stores inspected only 4.1%(n=41) were found compliant to regulatory requirements. Most of the stores 74.9%(n=752) were selling general items along with the drugs. Only 12%(n=124) stores were having qualified person working on the store, out of which 33% were pharmacist. 47.4%(n=400) of the stores had drug sales license displayed in the premises and 33.4%(n=282) of the stores had expired drug sales license. 11.4%(n=94) stores were found selling vaccines without proper refrigerator and only 11.7% stores had the power backup for the refrigerator. Only 40.2%(n=403) of stores were protected from direct sunlight and 5.4%(n=54) having air conditioning in the premises. Conclusion: The regulatory compliance of majority of the drug stores operated privately in different areas of Karachi is below standard. Only a few drugs stores have adequate facilities to protect the drugs from extreme temperature, sunlight and provision of refrigeration. Very few of the drug stores carry out drug sales under the supervision of qualified pharmacist. There is a dire need to improve the storage practices in the drug stores by complying with the regulatory standards/laws as specified by the Drug Regulatory Authority of Pakistan. PMID:27881996

Factors Associated With Child Maltreatment Among Children Aged 11 to 17 Years in Community Settings of Karachi, Pakistan, Using Belsky Ecological Framework.

PubMed

Lakhdir, Maryam Pyar Ali; Farooq, Salima; Khan, Uzma Rahim; Parpio, Yasmin; Azam, Syed Iqbal; Razzak, Junaid; Laljee, Anjiya Aslam; Kadir, Muhammad Masood

2017-08-01

Child maltreatment is considered as a global social issue and results as combined effect of parental background, socioeconomic environment, family structure, and child characteristics. The aim of this study was to determine factors associated with child maltreatment among children aged 11 to 17 years in Karachi, Pakistan. A cross-sectional survey of 800 pairs (children ranging from 11 to 17 years old and their parents) was randomly selected from 32 clusters of Karachi, using multistage cluster sampling. A structured questionnaire was adopted from the International Society for the Prevention of Child Abuse and Neglect (International Child Abuse Screening Tool for Parent [ICAST-P] and for Child [ICAST-C]). Multiple linear regression technique was used to assess the association of factors with child maltreatment score, by using STATA software. Our study found that children who always get bullied and mistreated by their siblings are at increased risk of getting maltreatment by parents (adjusted β: 10.78, 95% CI = [8.5, 13.05]).The mean estimated ICAST-C score increases by 9.86 (95% CI = [6.17, 13.55]) for children with exposure of verbal abuse and quarrel within family members. The mean estimated ICAST-C score increases by 5.09 among male children as compared with female children (95% CI = [3.65, 6.52]). Among children whose family always fight with each other and whose parents have exposure to childhood maltreatment, the mean estimated ICAST-C score increases by 22.25 (95% CI = [16.53, 27.98]). This study reflects the potential factors of child maltreatment in Karachi. Our findings provide evidence to raise awareness about child maltreatment.

Concentration of heavy metals in drinking water of different localities in district east Karachi.

PubMed

Jaleel, M A; Noreen, R; Baseer, A

2001-01-01

Several heavy metals are present in drinking water that play important roles in the body provided their level remains within the specified range recommended by WHO. But now due to the industrialization and rapid urbanization, the problems of pollution have surfaced. This study was designed to ascertain the contents of some heavy metals and then their variations if any in drinking water in different localities of district East of Karachi, Pakistan. Drinking water samples were collected from different sources and localities of district East of Karachi. The concentration of the heavy metals i.e. Lead, Arsenic, Copper, Iron, Mercury, Chromium, Manganese, Nickel, Cadmium and Zinc were determined by Atomic Absorption Spectrophotometry. PH was estimated by pH meter. Total dissolved solids (TDS) were calculated by formula. These concentrations of heavy metals, pH and TDS were compared with the standards set by WHO. Concentrations of lead and nickel were found to be significantly elevated as compared to WHO recommended levels in all the three sources of water (Piped water, Hand pump water and Tanker water supply). Chromium was found to be raised in hand pump water. Arsenic and Mercury were not detected in any source of water. Copper, iron, manganese, cadmium and zinc were found to be within the safe limits in all the three sources of water. pH was found to be within the range of WHO recommended level in all the three sources of water. TDS was found to be elevated in hand pump water and tanker water. Concentrations of lead and nickel were found to be significantly elevated as compared to WHO recommended levels in all the three sources of water in district East of Karachi.

Predictors of diarrheal mortality and patterns of caregiver health seeking behavior in in Karachi, Pakistan

PubMed Central

Qamar, Farah Naz; Zaman, Umber; Quadri, Farheen; Khan, Asia; Shaikh, Babar Tasneem; Azam, Iqbal; Nasrin, Dilruba; Kotloff, Karen; Levine, Myron; Brown, Nick; Zaidi, Anita K M

2016-01-01

Background Pakistan is unfortunately among the five countries that contributed to the most deaths due to diarrhea and pneumonia in 2010. To explore factors associated with diarrheal deaths we assessed care–seeking behavior and other predictors of diarrhea–related mortality in children in selected low–income peri–urban communities of Karachi, Pakistan. Methods A mixed methods study (qualitative and quantitative) using matched case–control design and focus group discussions with parents of children with moderate to severe diarrhea (MSD) was undertaken. Cases were children  <5 years of age who died within 60 days of developing an episode of MSD. Controls were age–matched children who survived after 60 days of an episode of MSD. Demographic, clinical, and care–related behavioral predictors of mortality were assessed. Conditional logistic regression was performed, matched adjusted odds ratios (mOR) are reported. Results Parents of 77 cases and 154 controls were interviewed. Cases were less likely to receive appropriate care compared to controls (mOR = 0.2, 95% confidence interval (CI) 0.05–0.91). Refusal for hospital admission (OR = 8.9, 95% CI 2.6–30.8), and delays in reaching the health facility (OR = 3.6, 95% CI 1.0–12.9) were significant independent predictors of mortality. We found strong beliefs in traditional and spiritual healing in the population; use of both modern and traditional/spiritual treatments concurrently was common. Conclusion Appropriate care seeking behavior predicts survival in children with diarrhea in Pakistan. There is a complex belief system relating to traditional and standard therapies. Health education for appropriate health care seeking should be implemented in order to achieve a substantial decline in diarrheal disease mortality in Pakistan. PMID:27606059

The Desirability of Medieval Germany: Some Observations on an Introductory Course

ERIC Educational Resources Information Center

Jillings, Lewis G.; Murdoch, Brian O.

1975-01-01

This paper discusses the problems and advantages of a course in Medieval Germany, including history, culture and literature along with language. Attention is given to issues and texts to be studied. (CHK)

Diathermy vs. scalpel skin incisions in general surgery: double-blind, randomized, clinical trial.

PubMed

Shamim, Muhammad

2009-08-01

This prospective, double-blind, randomized, controlled trial was designed to compare the outcome of diathermy incisions versus scalpel incisions in general surgery. A total of 369 patients who underwent diathermy incision (group A: 185 patients) or scalpel incision (group B: 184 patients) were analyzed. Variables analyzed were: surgical wound classification, length and depth of incision, incision time, duration of operation, incisional blood loss, postoperative pain, duration of hospital stay, duration of healing, and postoperative complications. The inclusion criteria were all patients who underwent elective or emergency general surgery. The exclusion criteria were only cases with incomplete patients' data and patients who were lost to follow-up. This study was conducted at Fatima Hospital-Baqai Medical University and Shamsi Hospital (Karachi), from January 2006 to December 2007. Incision time was significantly longer for patients in group B (p = 0.001). Incisional blood loss also was more for patients in group B (p = 0.000). Pain perception was found to be markedly reduced during the first 48 h in group A (p = 0.000). Total period of hospital stay (p = 0.129) and time for complete wound healing (p = 0.683) were almost the same for both groups. Postoperative complication rate by wound classification did not differ markedly between the two groups (p = 0.002 vs. p = 0.000). Diathermy incision has significant advantages compared with the scalpel because of reduced incision time, less blood loss, & reduced early postoperative pain.

Impact of delay in admission on the outcome of critically ill patients presenting to the emergency department of a tertiary care hospital from low income country.

PubMed

Khan, Badar Afzal; Shakeel, Nishi; Siddiqui, Emad Uddin; Kazi, Ghazala; Khan, Irum Qamar; Khursheed, Munawer; Feroze, Asher; Ejaz, Kiran; Khan, Sumaiya Tauseeq; Adel, Hatem

2016-05-01

To assess the impact of admission delay on the outcome of critical patients. The retrospective chart review was done at Aga Khan University Hospital, Karachi, and comprised adult patients visiting the Emergency Department during 2010. Outcome measures assessed were total hospital length of stay, total cost of the visit and in-hospital mortality. Patients admitted within 6 hours of presentation at Emergency Department were defined as non-delayed. Data was analysed using SPSS 19. Of the 49,532 patients reporting at the Emergency Department during the study period, 17,968 (36.3%) were admitted. Of them 2356(13%) were admitted to special or intensive care units, 1595(67.7%) of this sub-group stayed in the Emergency Department for >6 hours before being shifted to intensive care. The study focussed on 325(0.65%) of the total patients; 164(50.5%) in the non-delayed group and 161(49.5%) in the delayed group. The admitting diagnosis of myocardial infarction (p=0.00) and acute coronary syndrome (p=0.01) was significantly more common in the non-delayed group compared to other diagnoses like cerebrovascular attacks (p=0.03) which was significantly more common in the delayed group. There was no significant difference in the hospital length of stay between the two groups (p>0.05). The Emergency Department cost was significantly increased in the delayed group (p<0.05), but there was no difference in the overall hospital cost between the groups (p>0.05). There was no significant difference in the delayed and non-delayed groups, but long Emergency Department stays are distressing for both physicians and patients.

Genetic parameters for yearling weight, carcass traits, and primal-cut yields of Hanwoo cattle.

PubMed

Choi, T J; Alam, M; Cho, C I; Lee, J G; Park, B; Kim, S; Koo, Y; Roh, S H

2015-04-01

Genetic parameters associated with yearling weight, carcass traits, and primal-cut yields of male Hanwoo cattle were investigated using univariate and bivariate animal models. The mean yearling weight (YWT), carcass weight (CWT), longissimus muscle area (LMA), backfat thickness (BFT), and marbling score (MS) were 352.47 ± 0.40 kg, 337.39 ± 0.64 kg, 78.28 ± 0.13 cm2, 8.45 ± 0.05 mm, and 3.25 ± 0.03, respectively. Total primal-cut yield (TPC) was 78.95 ± 0.10% of CWT, of which 42.3% was contributed by the forequarters (chuck, CHK; shoulder, SLD; ribs, RIB; and brisket and flank, BAF). Loins, top round (TRND), and round (RND) were associated with yields of 13.57%, 5.45 ± 0.01%, and 8.87 ± 0.02%, respectively. The largest cut studied was ribs (15.67 ± 0.03%). The estimated heritabilities (h2) of YWT, CWT, LMA, BFT, and MS were 0.18 ± 0.02, 0.29 ± 0.04, 0.38 ± 0.05, 0.45 ± 0.05, and 0.62 ± 0.07, respectively. Shoulder yield was highly heritable in Hanwoo steers (0.83 ± 0.13), followed by the yields of round (0.66 ± 0.12), striploin (0.64 ± 0.12), top round (0.62 ± 0.12), sirloin (0.60 ± 0.12), and total primal-cut yield (0.52 ± 0.11). The h2 values of CHK, BAF, RIB, and tenderloin (TLN) ranged from 0.19 ± 0.09 to 0.41 ± 0.11. Generally, the genetic CV was low for most traits (2.33%-6.15%), except for CHK, BFT, and MS. The genetic correlation (rg) was strong between YWT and CWT (0.77 ± 0.06). The greatest positive and negative rg among carcass traits were those between LMA and CWT (0.52 ± 0.08) and between LMA and BFT (-0.30 ± 0.09), respectively. The correlation between CHK and SLD (0.81 ± 0.14), and those between SLD, TLN, TRND, and RND, were mostly strong (0.77-0.87), but the rg between RIB and other traits were strongly negative. The TPC yield showed moderate to high rg with most primal cuts. The YWT, CWT, and LMA correlated notably with CHK, SLD, and loin yields, especially LMA. However, BFT and MS were negatively correlated with many primal cuts but RIB. Those rg estimates were also opposite of that of LMA and CWT with primal cuts. Phenotypic correlations (rp) were generally weaker than rg estimates. The rp of YWT, CWT, and LMA were either zero or moderately negative compared to those of the BFT and MS with primal cuts. Most primal cuts yielded positive rp estimates among them, except for RIB. Our results suggest that direct selection for YWT, various carcass traits, and primal-cut yields may increase the carcass value of Hanwoo males.

Development of an economic skill building intervention to promote women's safety and child development in Karachi, Pakistan.

PubMed

Hirani, Saima Shams; Karmaliani, Rozina; McFarlane, Judith; Asad, Nargis; Madhani, Farhana; Shehzad, Shireen; Ali, Nazbano Ahmed

2010-02-01

Violence against women is a global epidemic phenomenon that can result in major mental health problems. Not only are women affected but also the health and well-being of their children are in jeopardy. To prevent violence and promote women's safety, several strategies have been tested in various cultural contexts. This article describes the process of developing and validating an economic skill building intervention for women of an urban slum area of Karachi, Pakistan. The purpose of the intervention is to increase women's economic independence, promote women's safety, and improve the behavioral functioning of their children.

Land contestation in Karachi and the impact on housing and urban development

PubMed Central

Hasan, Arif

2015-01-01

Karachi is one of the world’s fastest growing large cities. This paper describes the complex processes by which land is (formally and informally) made available for housing (and for commercial development), as well as who benefits – and how the low-income majority of Karachi citizens lose out. It also describes what underpins this – especially the political complications in a city that has grown so rapidly, has had fundamental changes in its ethnic composition (and thus also in its politics) and has attracted so many illegal immigrants. The paper describes the changes in formal and informal land markets over the last 50 years and the changing responses by government agencies to housing (and land for housing) issues. Also explored are the connections among land, housing and transport (which include different processes of densification) and the complex politics involved. The paper ends with recommendations for land titling, for changes in transport policies, for better use of land already owned by government agencies, for cross-political party agreement on how to address serious security issues (that are leading to loss of investment) and for increased political effectiveness of Karachi’s active civil society organizations. PMID:26321797

Hypertensive Crisis, Burden, Management, and Outcome at a Tertiary Care Center in Karachi.

PubMed

Almas, Aysha; Ghouse, Ayaz; Iftikhar, Ahmed Raza; Khursheed, Munawwar

2014-01-01

Objectives. Hypertension, if uncontrolled, can lead to hypertensive crisis. We aim to determine the prevalence of hypertensive crisis, its management, and outcome in patients presenting to a tertiary care center in Karachi. Methods. This was a cross-sectional study conducted at the Aga Khan University, Karachi, Pakistan. Adult inpatients (>18 yrs) presenting to the ER who were known hypertensive and had uncontrolled hypertension were included. Results. Out of 1336 patients, 28.6% (387) had uncontrolled hypertension. The prevalence of hypertensive crisis among uncontrolled hypertensive was 56.3% (218). Per oral calcium channel blocker; 35.4% (137) and intravenous nitrate; 22.7% (88) were the most commonly administered medication in the ER. The mean (SD) drop in SBP in patients with hypertensive crisis on intravenous treatment was 53.1 (29) mm Hg and on per oral treatment was 43 (27) mm Hg. The maximum mean (SD) drop in blood pressure was seen by intravenous sodium nitroprusside; 80 (51) mm Hg in SBP. Acute renal failure was the most common complication with a prevalence of 11.5% (24). Conclusion. The prevalence of hypertensive crisis is high. Per oral calcium channel blocker and intravenous nitrate are the most commonly administered medications in our setup.

Teaching Hispanic Culture through Folk Music

ERIC Educational Resources Information Center

Griffin, Robert J.

1977-01-01

Folk music is musical expression of deep culture, and is therefore a useful tool in teaching culture in the language class. The use of Spanish music to teach Hispanic culture is described. Useful books and music are suggested. (CHK)

Wild-type H- and N-Ras promote mutant K-Ras driven tumorigenesis by modulating the DNA damage response

PubMed Central

Grabocka, Elda; Pylayeva-Gupta, Yuliya; Jones, Mathew JK; Lubkov, Veronica; Yemanaberhan, Eyoel; Taylor, Laura; Jeng, Hao Hsuan; Bar-Sagi, Dafna

2014-01-01

SUMMARY Mutations in KRAS are prevalent in human cancers and universally predictive of resistance to anti-cancer therapeutics. Although it is widely accepted that acquisition of an activating mutation endows RAS genes with functional autonomy, recent studies suggest that the wild-type forms of Ras may contribute to mutant Ras-driven tumorigenesis. Here we show that downregulation of wild-type H-Ras or N-Ras in mutant K-Ras cancer cells leads to hyperactivation of the Erk/p90RSK and PI3K/Akt pathways, and consequently, the phosphorylation of Chk1 at an inhibitory site, Ser 280. The resulting inhibition of ATR/Chk1 signaling abrogates the activation of the G2 DNA damage checkpoint and confers specific sensitization of mutant K-Ras cancer cells to DNA damage chemotherapeutic agents in vitro and in vivo. PMID:24525237

Las uniones conjuntivas en espanol (Conjunctive Correspondences in Spanish)

ERIC Educational Resources Information Center

Perez Botero, Luis

1977-01-01

This study of the medieval Spanish concept of order examines uses made of the word "y" ("and") in Spanish medieval writing to join words and phrases connoting social, natural and human order. (Text is in Spanish.) (CHK)

Delaware Anatomy: With Linguistic, Social, and Medical Aspects

ERIC Educational Resources Information Center

Miller, Jay

1977-01-01

Presents the comprehensive partonomy of anatomy in Unami Lenape or Delaware as provided by a modern Unami specialist. The primary referent is the human body, but some comparative terms referring to animals and plants are also provided. (CHK)

Experiences in the Bilingual Education of a Child of Pre-School Age

ERIC Educational Resources Information Center

Zierer, Ernesto

1977-01-01

This article reports on experiences in the bilingual education, psychologically and pedagogically planned, of a child who died of brain cancer at age 5. Conclusions are drawn regarding order and method of language learning. (CHK)

A Suggested Curriculum Outline for German in Secondary Schools

ERIC Educational Resources Information Center

Clutterbuck, J. M.

1975-01-01

Outlines a four-year program of German study aiming to give students a basic ability in spoken and written German, knowledge of German culture, and preparation for advanced German study. Study topics and textbooks are included. (CHK)

"John is Easy to See" Re-Investigated

ERIC Educational Resources Information Center

Morsbach, Gisela; Steel, Pamela M.

1976-01-01

This paper discusses C. Chomsky's 1969 paper on children's syntactic development and the subsequent studies made to test her findings. Later studies indicate that Chomsky's results were not clearly differentiated, and a slight alteration in procedure changes results significantly. (CHK)

How to improve outcome in surgery for Proximal Hypospadias?

PubMed

Qureshi, Abdul Hafeez; Zaidi, Syed Zafar

2016-02-01

To evaluate the role of subdartos fascial tissue as watertight layer in improving outcome for 2-stage proximal hypospadias surgery. The experimental study was conducted at the Department of Urology, Indus Hospital, Karachi, and comprised an audit of patients with proximal hypospadias who underwent surgery from July 1, 2007, to December 31, 2011. The initial two-stage repair of proximal hypospadias led to a high rate of urethrocutanous fistula formation (Group A), and, thus, a modification was introduced and subdartos facial double layer was applied over the urethral suture line (Group B). The results were compared regarding age, type of hypospadias, graft failure and urethrocutanous fistula in these patients. There were 27 patients in Group A and 16(59.3%) of them ended up having urethrocutanous fistula. Group B had 25 patients and only 2(8%) had fistula formation. The application of dartos facial flap waterproofing layer reduced fistula rate.

Trifluorothymidine exhibits potent antitumor activity via the induction of DNA double-strand breaks.

PubMed

Suzuki, Norihiko; Nakagawa, Fumio; Nukatsuka, Mamoru; Fukushima, Masakazu

2011-05-01

TAS-102 is an oral anticancer drug composed of trifluorothymidine (TFT) and TPI (an inhibitor of thymidine phosphorylase that strongly inhibits the biodegradation of TFT). Similar to 5-fluorouracil (5FU) and 5-fluoro-2'-deoxyuridine (FdUrd), TFT also inhibits thymidylate synthase (TS), a rate-limiting enzyme of DNA biosynthesis, and is incorporated into DNA. TFT exhibits an anticancer effect on colorectal cancer cells that have acquired 5FU and/or FdUrd resistance as a result of the overexpression of TS. Therefore, we examined the mode of action of TFT-induced DNA damage after its incorporation into DNA. When HeLa cells were treated with TFT, the number of ring-open aldehyde forms at apurinic/apyrimidinic sites increased in a dose-dependent manner, although we previously reported that no detectable excisions of TFT paired to adenine were observed using uracil DNA glycosylases, thymine DNA glycosylase or methyl-CpG binding domain 4 and HeLa whole cell extracts. To investigate the functional mechanism of TFT-induced DNA damage, we measured the phosphorylation of ATR, ATM, BRCA2, chk1 and chk2 in nuclear extracts of HeLa cells after 0, 24, 48 or 72 h of exposure to an IC(50) concentration of TFT, FdUrd or 5FU using Western blot analysis or an enzyme-linked immunosorbent assay (ELISA). Unlike FdUrd and 5FU, TFT resulted in an earlier phosphorylation of ATR and chk1 proteins after only 24 h of exposure, while phosphorylated ATM, BRCA2 and chk2 proteins were detected after more than 48 h of exposure to TFT. These results suggest that TFT causes single-strand breaks followed by double-strand breaks in the DNA of TFT-treated cells. TFT (as TAS-102) showed a more potent antitumor activity than oral 5FU on CO-3 colon cancer xenografts in mice, and such antitumor potency was supported by the increased number of double-strand breaks occurring after single-strand breaks in the DNA of the TFT-treated tumors. These results suggest that TFT causes single-strand breaks after its incorporation into DNA followed by double-strand breaks, resulting in DNA damage. This effect of TFT on DNA may explain its potent anticancer activity in cancer therapy.

Trifluorothymidine exhibits potent antitumor activity via the induction of DNA double-strand breaks

PubMed Central

SUZUKI, NORIHIKO; NAKAGAWA, FUMIO; NUKATSUKA, MAMORU; FUKUSHIMA, MASAKAZU

2011-01-01

TAS-102 is an oral anticancer drug composed of trifluorothymidine (TFT) and TPI (an inhibitor of thymidine phosphorylase that strongly inhibits the biodegradation of TFT). Similar to 5-fluorouracil (5FU) and 5-fluoro-2′-deoxyuridine (FdUrd), TFT also inhibits thymidylate synthase (TS), a rate-limiting enzyme of DNA biosynthesis, and is incorporated into DNA. TFT exhibits an anticancer effect on colorectal cancer cells that have acquired 5FU and/or FdUrd resistance as a result of the overexpression of TS. Therefore, we examined the mode of action of TFT-induced DNA damage after its incorporation into DNA. When HeLa cells were treated with TFT, the number of ring-open aldehyde forms at apurinic/apyrimidinic sites increased in a dose-dependent manner, although we previously reported that no detectable excisions of TFT paired to adenine were observed using uracil DNA glycosylases, thymine DNA glycosylase or methyl-CpG binding domain 4 and HeLa whole cell extracts. To investigate the functional mechanism of TFT-induced DNA damage, we measured the phosphorylation of ATR, ATM, BRCA2, chk1 and chk2 in nuclear extracts of HeLa cells after 0, 24, 48 or 72 h of exposure to an IC50 concentration of TFT, FdUrd or 5FU using Western blot analysis or an enzyme-linked immunosorbent assay (ELISA). Unlike FdUrd and 5FU, TFT resulted in an earlier phosphorylation of ATR and chk1 proteins after only 24 h of exposure, while phosphorylated ATM, BRCA2 and chk2 proteins were detected after more than 48 h of exposure to TFT. These results suggest that TFT causes single-strand breaks followed by double-strand breaks in the DNA of TFT-treated cells. TFT (as TAS-102) showed a more potent antitumor activity than oral 5FU on CO-3 colon cancer xenografts in mice, and such antitumor potency was supported by the increased number of double-strand breaks occurring after single-strand breaks in the DNA of the TFT-treated tumors. These results suggest that TFT causes single-strand breaks after its incorporation into DNA followed by double-strand breaks, resulting in DNA damage. This effect of TFT on DNA may explain its potent anticancer activity in cancer therapy. PMID:22977515

Pattern of unintentional burns: A hospital based study from Pakistan.

PubMed

Adil, Syed Omair; Ibran, Ehmer-Al; Nisar, Nighat; Shafique, Kashif

2016-09-01

Burns are major cause of morbidity and mortality in developing countries. Better understanding of the nature and extent of injury remains the major and only available way to halt the occurrence of the event. The present study was conducted to determine the prevalence of by self and by other unintentional burn, their comparison and the possible mode of acquisition by obtaining the history of exposure to known risk factors. A cross-sectional questionnaire based survey was conducted in Burns Centre of Civil Hospital Karachi, Pakistan and 324 hospitalized adult patients with unintentional burns were consecutively interviewed during August 2013 to February 2014. Information was collected on socio-demographic profile. The source of burn, affected body part and place of injury acquisition in terms of home, outside or work were also noted. Logistic regression model was conducted using SPSS software. Out of 324 patients, 295 (91%) had unintentional burn by self and 29 (9%) had unintentional burn by others. Male gender were 2.37 times and no schooling were 1.75 times more likely to have self-inflicted unintentional burn. Lower limb and head and neck were less likely to involve in unintentional burn by self. The burden of unintentional burn by self was considerably higher. Male gender and no schooling were found more at risk to have unintentional burn by self. Copyright © 2016 Elsevier Ltd and ISBI. All rights reserved.

Paginas del estudiante de espanol (Study Pages for the Spanish Student)

ERIC Educational Resources Information Center

Carballo Picazo, Alfredo

1977-01-01

This Spanish lesson consists of an essay on the use of "usted" and "tu," followed by a series of exercises including questions on the text, vocabulary, grammar and the use of the subjunctive. (Text is in Spanish.) (CHK)

Banners and Bandwagons

ERIC Educational Resources Information Center

Close, R. A.

1977-01-01

Linguistic theories have a great effect on classroom language teaching methods, and shifts in theory popularity can cause confusion among language teachers. A broad understanding of theory and practice is necessary to provide balance and to select the right teaching method for each occasion. (CHK)

Perspectives on domestic violence: case study from Karachi, Pakistan.

PubMed

Rabbani, F; Qureshi, F; Rizvi, N

2008-01-01

There is no adequate profile of domestic violence in Pakistan although this issue is frequently highlighted by the media. This case study used qualitative and quantitative methods to explore the nature and forms of domestic violence, circumstances, impact and coping mechanisms amongst selected women victims in Karachi. Violence was a continuum: all the women reported verbal abuse, often escalating into physical, emotional, sexual and economic abuse. The husband was the most common perpetrator. Women suffered in silence due to sociocultural norms, misinterpretation of religious beliefs, subordinate status, economic dependence and lack of legal redress. Besides short-term local measures, public policy informed by correct interpretation of religion can bring about a change in prevailing societal norms.

Socio-demographic correlates of exhaled breath carbon monoxide in Karachi's adult population.

PubMed

Shafiq, Majid; Khan, Sumera; Khawaja, M Rizwanulhaq; Haque, Suleman; Khan, Javaid A

2008-02-01

To examine the relationship between CO levels and putative factors including smoking status among residents of Karachi, an urban center with very high levels of air pollution. Two hundred and eighteen volunteering subjects were asked to maximally exhale into a Smokerlyzer breath CO analyzer. Each of the volunteers was also asked to reply to a questionnaire-based interview seeking demographic information as well as details of exposure to tobacco, traffic fumes and other air pollutants. Out of the 218 participating subjects, 75% were males and 27% were current or ex-smokers. The mean CO level was 2.92 parts per million (ppm). Cigarette smoking was the only factor found to influence CO levels. Number of cigarettes smoked per day was directly related to CO levels, while time since the last smoke was inversely related. There was no difference in CO levels between ex-smokers and never-been-smokers. Years of residence in Karachi, quantitative exposure to traffic and perception of occupational exposure to air pollutants were not associated with CO levels. Smoking status, number of cigarettes smoked per day and time since last smoke correlated well with exhaled breath CO levels, in spite of high air pollution levels. This tool therefore continues to provide a valid and real-time assessment of a subject's current smoking status.

Hypertensive Crisis, Burden, Management, and Outcome at a Tertiary Care Center in Karachi

PubMed Central

Almas, Aysha; Ghouse, Ayaz; Iftikhar, Ahmed Raza; Khursheed, Munawwar

2014-01-01

Objectives. Hypertension, if uncontrolled, can lead to hypertensive crisis. We aim to determine the prevalence of hypertensive crisis, its management, and outcome in patients presenting to a tertiary care center in Karachi. Methods. This was a cross-sectional study conducted at the Aga Khan University, Karachi, Pakistan. Adult inpatients (>18 yrs) presenting to the ER who were known hypertensive and had uncontrolled hypertension were included. Results. Out of 1336 patients, 28.6% (387) had uncontrolled hypertension. The prevalence of hypertensive crisis among uncontrolled hypertensive was 56.3% (218). Per oral calcium channel blocker; 35.4% (137) and intravenous nitrate; 22.7% (88) were the most commonly administered medication in the ER. The mean (SD) drop in SBP in patients with hypertensive crisis on intravenous treatment was 53.1 (29) mm Hg and on per oral treatment was 43 (27) mm Hg. The maximum mean (SD) drop in blood pressure was seen by intravenous sodium nitroprusside; 80 (51) mm Hg in SBP. Acute renal failure was the most common complication with a prevalence of 11.5% (24). Conclusion. The prevalence of hypertensive crisis is high. Per oral calcium channel blocker and intravenous nitrate are the most commonly administered medications in our setup. PMID:26464857

Induced abortions in low socio-economic settlements of Karachi, Pakistan: rates and women's perspectives.

PubMed

Saleem, S; Fikree, F F

2001-08-01

The aim of the study was to determine rates on induced abortions and to identify the perceived and actual reasons for terminating an unplanned pregnancy, health care providers sought, methods used and post-abortion complications. Three squatter settlements of Karachi, Pakistan. Interviews were conducted on 1,214 ever-married women in the reproductive age group (15-49) with a reproductive history of at least one pregnancy, irrespective of outcome. A cross-sectional survey from June-August 1997 was conducted in three selected squatter settlements of Karachi. The abortion rate for the past year was 25.5 per 1,000 women of reproductive age group. The post-abortion complication rate reported was 68.5% (61/89), of which fever and heavy vaginal bleeding was the most commonly reported complication (54.1%). The results indicate that women are aware of the high mortality and morbidity risk resulting from seeking an unsafe abortion but nevertheless opt for this approach to attain their goal of small family size rather than for a modern method of contraception. Furthermore, healthcare providers, irrespective of legality issues, provide such services due to demand. We suggest that family physicians and other relevant health care providers be trained for post-abortion care including post-abortion family planning counseling with an emphasis on emergency contraceptives.

Relapses vs. reactions in multibacillary leprosy: proposal of new relapse criteria.

PubMed

Linder, Katharina; Zia, Mutaher; Kern, Winfried V; Pfau, Ruth K M; Wagner, Dirk

2008-03-01

To compare a new scoring system for multibacillary (MB) leprosy relapses, which combines time factor, risk factors and clinical presentation at relapse, to WHO criteria. Data were collected on all relapses diagnosed between 1998 and 2004 at the Marie-Adelaide-Centre in Karachi, Pakistan, including case histories, clinical manifestations, follow-up, bacterial indices, treatment and contacts. For the diagnosis of MB relapses a simple scoring system was developed and validated on a data-set of mouse foot pads (MFP)-confirmed relapses (Leprosy Reviews, 76, 2005, 241). Its sensitivity was further evaluated in the Karachi relapse cohort. The P-value was calculated with McNemar's test with continuity correction. The new scoring system that combines time factor, risk factors and clinical presentation at relapse had a higher sensitivity in MFP-confirmed relapses than the WHO-criteria (95%vs. 65%, P < 0.01). The sensitivity of the scoring system was also significantly higher than the WHO criteria in the 57 cases of MB-relapses diagnosed in Karachi (72%vs. 54%, P < 0.05). This new simple scoring system for diagnosing MB-relapses in leprosy should be further validated in a prospective study to confirm its superior sensitivity and to evaluate the specificity of these criteria by using MFP-confirmation for patients presenting with signs of activity after treatment.

"Standard" versus "Dialect" in Bilingual Education: An Old Problem in a New Context

ERIC Educational Resources Information Center

Fishman, Joshua A.

1977-01-01

A survey discussion of the question of standard languages versus dialects in education observes practice and conditions in America and Europe with attention to the definition of dialect. Responsibilities of the bilingual education teacher are outlined. (CHK)

On a Method of Eliciting True/False Judgments from Young Children

ERIC Educational Resources Information Center

Lloyd, Peter; Donaldson, Margaret

1976-01-01

Experiments in eliciting true/false judgments from young children aged 3-5 used a "talking doll," a toy panda with a speaker installed. The procedure has been used in studies of language comprehension, communication skills, and free conversation experiments. (CHK)

Antimicrobial resistance and Neisseria gonorrhoeae multiantigen sequence typing (NG-MAST) genotypes in N. gonorrhoeae during 2012-2014 in Karachi, Pakistan.

PubMed

Jabeen, Kauser; Bhawan Mal, Pushpa; Khan, Erum; Chandio, Saeeda; Jacobsson, Susanne; Unemo, Magnus

2016-07-22

Globally, increasing antimicrobial resistance (AMR) in Neisseria gonorrhoea has led to decreased treatment options for gonorrhoea. Continuous monitoring of resistance is crucial to determine evolving resistance trends in Neisseria gonorrhoea and to suggest treatment recommendations. Quality assured gonococcal AMR data from Pakistan are mainly lacking. This study was performed to determine prevalence and trends of gonococcal AMR and molecular epidemiology of local strains during 2012-2014 in Karachi, Pakistan. Gonococcal isolates (n = 100) were obtained from urogenital specimens submitted to the Aga Khan University Laboratory, Karachi, Pakistan. Antimicrobial susceptibility was determined using Etest and molecular epidemiology was assessed by N. gonorrhoeae multiantigen sequence typing (NG-MAST). Quality control was performed using N. gonorrhoeae WHO reference strains C, F, G, K, L, M, N, O, and P, and ATCC 49226. Susceptibility to spectinomycin, ceftriaxone and cefixime was 100 % and to azithromycin was 99 %. All isolates had low ceftriaxone MICs, i.e., ≤0.032 mg/L. Resistance to ciprofloxacin, tetracycline and penicillin G were 86 %, 51 % and 43 %, respectively. NG-MAST analysis identified 74 different sequence types (STs). A highly diversified gonococcal population, 74 NG-MAST STs (62 novel STs) with an increased resistance to penicillin G, ciprofloxacin and tetracycline circulated in Karachi, Pakistan. Fortunately, no resistance to ceftriaxone was detected. Accordingly, ceftriaxone can continuously be recommended as the treatment of choice. However it is recommended to increase the dose of ceftriaxone from 125 mg intramuscularly to 250 mg intramuscularly due to ceftriaxone MIC creep and emerging resistance reported in the region. Furthermore, due to the high level of resistance to ciprofloxacin (86 %) it is essential to exclude ciprofloxacin from the recommended first-line therapy. It is imperative to significantly broaden the gonococcal AMR monitoring with participation from other laboratories and cities in Pakistan.

Rise in childhood obesity with persistently high rates of undernutrition among urban school-aged Indo-Asian children.

PubMed

Jafar, T H; Qadri, Z; Islam, M; Hatcher, J; Bhutta, Z A; Chaturvedi, N

2008-05-01

Childhood obesity is an emerging global public health challenge. Evidence for the transition in nutrition in Indo-Asian developing countries is lacking. We conducted these analyses to determine the trends in nutritional status of school-aged children in urban Pakistan. Data on the nutritional status of children aged 5 to 14 years from two independent population-based representative surveys, the urban component of the National Health Survey of Pakistan (NHSP; 1990-1994) and the Karachi survey (2004-2005), were analysed. Using normative data from children in the United States as the reference, trends for age- and gender-standardised prevalence (95% CI) of underweight (more than 2 SD below the weight-for-age reference), stunted (more than 2 SD below the height-for-age reference) and overweight and obese (body mass index (BMI) 85(th) percentile or greater) children were compared for the two surveys. The association between physical activity and being overweight or obese was analysed in the Karachi survey using logistical regression analysis. 2074 children were included in the urban NHSP and 1675 in the Karachi survey. The prevalence of underweight children was 29.7% versus 27.3% (p = 0.12), stunting was 16.7% versus 14.3% (p = 0.05), and prevalence of overweight and obese children was 3.0 versus 5.7 (p<0.001) in the NHSP and Karachi surveys, respectively. Physical activity was inversely correlated with being overweight or obese (odds ratio, 95% CI, 0.51, 0.32-0.80 for those who engaged in more than 30 minutes of physical activity versus those engaged in less than 30 minutes' activity). Our study highlights the challenge faced by Pakistani school-aged children. There has been a rapid rise in the number of overweight and obese children despite a persistently high burden of undernutrition. Focus on prevention of obesity in children must include strategies for promoting physical activity.

Assessing the effect of dietary calcium intake and 25 OHD status on bone turnover in women in Pakistan.

PubMed

Khan, Aysha Habib; Naureen, Ghazala; Iqbal, Romaina; Dar, Farhan Javed

2013-01-01

Bone health assessed in three towns of Karachi, Pakistan in females showed poor calcium intake, vitamin D deficiency, secondary hyperparathyroidism, and high bone turnover. Correlates of high bone turnover included females residing in Saddar Town, underweight females less than 30 years of age from low socio-economic status, and secondary hyperparathyroidism. To assess bone health and association of dietary calcium and 25 hydroxy vitamin D with bone turnover in the community-dwelling females of Karachi. Bone health was assessed in three randomly selected towns of Karachi, Pakistan. One premenopausal female fulfilling the inclusion criteria from each household was included in the study. Dietary calcium was assessed through a food frequency questionnaire and biochemical markers including calcium, phosphates, albumin, magnesium, creatinine, and SGPT, intact parathyroid hormone, 25 hydroxy vitamin D, and N-telopeptide of type I collagen were measured to assess the bone health. Three hundred and five females were included from three towns. Overall, 90.5% of females had vitamin D deficiency with 42.6 and 23.3% having secondary hyperparathyroidism and high bone turn over respectively. Prevalence of vitamin D deficiency, secondary hyperparathyroidism, and high bone turnover was significantly different among towns. Mean vitamin D levels were significantly low and iPTH levels significantly high in females with high bone turnover. Calcium intake was not significantly different among females with normal, high, and low bone turnover. Correlates of high bone turnover included females residing in Saddar Town, underweight females less than 30 years of age belonging to low socio-economic status, and secondary hyperparathyroidism. Compromised bone health is seen in community-dwelling females of Karachi. There is a need to perform large-scale community-based studies in all age groups to understand the interplay of markers in our population to understand the impact of these variables translating into the risk of osteoporosis.

Rise in childhood obesity with persistently high rates of undernutrition among urban school-aged Indo-Asian children

PubMed Central

Jafar, T H; Qadri, Z; Islam, M; Hatcher, J; Bhutta, Z A; Chaturvedi, N

2008-01-01

Background: Childhood obesity is an emerging global public health challenge. Evidence for the transition in nutrition in Indo-Asian developing countries is lacking. We conducted these analyses to determine the trends in nutritional status of school-aged children in urban Pakistan. Methods: Data on the nutritional status of children aged 5 to 14 years from two independent population-based representative surveys, the urban component of the National Health Survey of Pakistan (NHSP; 1990–1994) and the Karachi survey (2004–2005), were analysed. Using normative data from children in the United States as the reference, trends for age- and gender-standardised prevalence (95% CI) of underweight (more than 2 SD below the weight-for-age reference), stunted (more than 2 SD below the height-for-age reference) and overweight and obese (body mass index (BMI) 85th percentile or greater) children were compared for the two surveys. The association between physical activity and being overweight or obese was analysed in the Karachi survey using logistical regression analysis. Results: 2074 children were included in the urban NHSP and 1675 in the Karachi survey. The prevalence of underweight children was 29.7% versus 27.3% (p = 0.12), stunting was 16.7% versus 14.3% (p = 0.05), and prevalence of overweight and obese children was 3.0 versus 5.7 (p<0.001) in the NHSP and Karachi surveys, respectively. Physical activity was inversely correlated with being overweight or obese (odds ratio, 95% CI, 0.51, 0.32–0.80 for those who engaged in more than 30 minutes of physical activity versus those engaged in less than 30 minutes’ activity). Conclusions: Our study highlights the challenge faced by Pakistani school-aged children. There has been a rapid rise in the number of overweight and obsese children despite a persistently high burden of undernutrition. Focus on prevention of obesity in children must include strategies for promoting physical activity. PMID:17942586

Studies on battery repair and recycling workers occupationally exposed to lead in Karachi.

PubMed

Haider, Muhammad Jamal; Qureshi, Naeemullah

2013-01-01

OBJECTIVE. The present study was carried out to investigate the effects of occupational lead exposure on the hematological and biochemical parameters in occupationally exposed and non exposed inhabitants of Karachi. MATERIAL AND METHODS. In 100 lead exposed subjects recruited from automobile workshops, lead battery repair and recycling units located in Karachi and in 100 control subjects the general health status, hematological parameters and exposure markers for lead were measured. RESULTS. Results indicated that the mean values of blood lead level and delta-aminolevulinic acid were significantly higher (P<0.05) while the activity of delta-aminolevulinic acid dehydratase were significantly decreased (P<0.05) among battery repair and recycling workers as compared to controls. The abnormalities in the blood lead level, delta-aminolevulinic acid and delta-aminolevulinic acid dehydratase were more frequent in lead exposed battery repair workers when compared with control subjects. The blood lead levels and deltaaminolevulinic acid were positively correlated while delta-aminolevulinic acid dehydratase was found to be negatively correlated with age, years of exposure and years of employment. Blood lead level was positively correlated with hemoglobin and RBC count while delta-aminolevulinic acid dehydratase was negatively correlated with hemoglobin concentration. The work related symptoms, droopiness, nasal symptoms and muscular pain were more frequent among battery repair workers as compared to control group. The findings of present study confirmed that occupational exposure to lead is associated with deviation in important hematological parameters and biological markers of exposure to lead among lead exposed workers, and also confirms the impact of lead exposure in the development of adverse effects among lead exposed workers. The study provides the data for risk assessment in lead battery repair workers of Karachi and suggests the need for preventive measures for battery repair workers and improvements to reduce occupational lead exposures to protect them from lead toxicity. It is suggested that hematological and physical examinations of lead exposed workers should be carried out periodically to prevent future health hazards.

A Bioinformatics Approach Identifies Signal Transducer and Activator of Transcription-3 and Checkpoint Kinase 1 as Upstream Regulators of Kidney Injury Molecule-1 after Kidney Injury

PubMed Central

Ajay, Amrendra Kumar; Kim, Tae-Min; Ramirez-Gonzalez, Victoria; Park, Peter J.; Frank, David A.

2014-01-01

Kidney injury molecule-1 (KIM-1)/T cell Ig and mucin domain-containing protein-1 (TIM-1) is upregulated more than other proteins after AKI, and it is highly expressed in renal damage of various etiologies. In this capacity, KIM-1/TIM-1 acts as a phosphatidylserine receptor on the surface of injured proximal tubular epithelial cells, mediating phagocytosis of apoptotic cells, and it may also act as a costimulatory molecule for immune cells. Despite recognition of KIM-1 as an important therapeutic target for kidney disease, the regulators of KIM-1 transcription in the kidney remain unknown. Using a bioinformatics approach, we identified upstream regulators of KIM-1 after AKI. In response to tubular injury in rat and human kidneys or oxidant stress in human proximal tubular epithelial cells (HPTECs), KIM-1 expression increased significantly in a manner that corresponded temporally and regionally with increased phosphorylation of checkpoint kinase 1 (Chk1) and STAT3. Both ischemic and oxidant stress resulted in a dramatic increase in reactive oxygen species that phosphorylated and activated Chk1, which subsequently bound to STAT3, phosphorylating it at S727. Furthermore, STAT3 bound to the KIM-1 promoter after ischemic and oxidant stress, and pharmacological or genetic induction of STAT3 in HPTECs increased KIM-1 mRNA and protein levels. Conversely, inhibition of STAT3 using siRNAs or dominant negative mutants reduced KIM-1 expression in a kidney cancer cell line (769-P) that expresses high basal levels of KIM-1. These observations highlight Chk1 and STAT3 as critical upstream regulators of KIM-1 expression after AKI and may suggest novel approaches for therapeutic intervention. PMID:24158981

CHK1-targeted therapy to deplete DNA replication-stressed, p53-deficient, hyperdiploid colorectal cancer stem cells

PubMed Central

Russo, Giorgio; Corradi, Francesca; Siteni, Silvia; Musella, Martina; Vitale, Sara; De Angelis, Maria Laura; Pallocca, Matteo; Amoreo, Carla Azzurra; Sperati, Francesca; Di Franco, Simone; Barresi, Sabina; Policicchio, Eleonora; De Luca, Gabriele; De Nicola, Francesca; Mottolese, Marcella; Zeuner, Ann; Fanciulli, Maurizio; Stassi, Giorgio; Maugeri-Saccà, Marcello; Baiocchi, Marta; Tartaglia, Marco

2018-01-01

Objective Cancer stem cells (CSCs) are responsible for tumour formation and spreading, and their targeting is required for tumour eradication. There are limited therapeutic options for advanced colorectal cancer (CRC), particularly for tumours carrying RAS-activating mutations. The aim of this study was to identify novel CSC-targeting strategies. Design To discover potential therapeutics to be clinically investigated as single agent, we performed a screening with a panel of FDA-approved or investigational drugs on primary CRC cells enriched for CSCs (CRC-SCs) isolated from 27 patients. Candidate predictive biomarkers of efficacy were identified by integrating genomic, reverse-phase protein microarray (RPPA) and cytogenetic analyses, and validated by immunostainings. DNA replication stress (RS) was increased by employing DNA replication-perturbing or polyploidising agents. Results The drug-library screening led to the identification of LY2606368 as a potent anti-CSC agent acting in vitro and in vivo in tumour cells from a considerable number of patients (∼36%). By inhibiting checkpoint kinase (CHK)1, LY2606368 affected DNA replication in most CRC-SCs, including RAS-mutated ones, forcing them into premature, lethal mitoses. Parallel genomic, RPPA and cytogenetic analyses indicated that CRC-SCs sensitive to LY2606368 displayed signs of ongoing RS response, including the phosphorylation of RPA32 and ataxia telangiectasia mutated serine/threonine kinase (ATM). This was associated with mutation(s) in TP53 and hyperdiploidy, and made these CRC-SCs exquisitely dependent on CHK1 function. Accordingly, experimental increase of RS sensitised resistant CRC-SCs to LY2606368. Conclusions LY2606368 selectively eliminates replication-stressed, p53-deficient and hyperdiploid CRC-SCs independently of RAS mutational status. These results provide a strong rationale for biomarker-driven clinical trials with LY2606368 in patients with CRC. PMID:28389531

The Error-Prone DNA Polymerase κ Promotes Temozolomide Resistance in Glioblastoma through Rad17-Dependent Activation of ATR-Chk1 Signaling.

PubMed

Peng, Chenghao; Chen, Zhengxin; Wang, Shuai; Wang, Hong-Wei; Qiu, Wenjin; Zhao, Lin; Xu, Ran; Luo, Hui; Chen, Yuanyuan; Chen, Dan; You, Yongping; Liu, Ning; Wang, Huibo

2016-04-15

The acquisition of drug resistance is a persistent clinical problem limiting the successful treatment of human cancers, including glioblastoma (GBM). However, the molecular mechanisms by which initially chemoresponsive tumors develop therapeutic resistance remain poorly understood. In this study, we report that Pol κ, an error-prone polymerase that participates in translesion DNA synthesis, was significantly upregulated in GBM cell lines and tumor tissues following temozolomide treatment. Overexpression of Pol κ in temozolomide-sensitive GBM cells conferred resistance to temozolomide, whereas its inhibition markedly sensitized resistant cells to temozolomide in vitro and in orthotopic xenograft mouse models. Mechanistically, depletion of Pol κ disrupted homologous recombination (HR)-mediated repair and restart of stalled replication forks, impaired the activation of ATR-Chk1 signaling, and delayed cell-cycle re-entry and progression. Further investigation of the relationship between Pol κ and temozolomide revealed that Pol κ inactivation facilitated temozolomide-induced Rad17 ubiquitination and proteasomal degradation, subsequently silencing ATR-Chk1 signaling and leading to defective HR repair and the reversal of temozolomide resistance. Moreover, overexpression of Rad17 in Pol κ-depleted GBM cells restored HR efficiency, promoted the clearance of temozolomide-induced DNA breaks, and desensitized cells to the cytotoxic effects of temozolomide observed in the absence of Pol κ. Finally, we found that Pol κ overexpression correlated with poor prognosis in GBM patients undergoing temozolomide therapy. Collectively, our findings identify a potential mechanism by which GBM cells develop resistance to temozolomide and suggest that targeting the DNA damage tolerance pathway may be beneficial for overcoming resistance. Cancer Res; 76(8); 2340-53. ©2016 AACR. ©2016 American Association for Cancer Research.

A phase I, pharmacokinetic, and pharmacodynamic study of panobinostat, an HDAC inhibitor, combined with erlotinib in patients with advanced aerodigestive tract tumors.

PubMed

Gray, Jhanelle E; Haura, Eric; Chiappori, Alberto; Tanvetyanon, Tawee; Williams, Charles C; Pinder-Schenck, Mary; Kish, Julie A; Kreahling, Jenny; Lush, Richard; Neuger, Anthony; Tetteh, Leticia; Akar, Angela; Zhao, Xiuhua; Schell, Michael J; Bepler, Gerold; Altiok, Soner

2014-03-15

Panobinostat, a histone deacetylase (HDAC) inhibitor, enhances antiproliferative activity in non-small cell lung cancer (NSCLC) cell lines when combined with erlotinib. We evaluated this combination in patients with advanced NSCLC and head and neck cancer. Eligible patients were enrolled in a 3+3 dose-escalation design to determine the maximum tolerated dose (MTD) of twice weekly panobinostat plus daily erlotinib at four planned dose levels (DL). Pharmacokinetics, blood, fat pad biopsies (FPB) for histone acetylation, and paired pre and posttherapy tumor biopsies for checkpoint kinase 1 (CHK1) expression were assessed. Of 42 enrolled patients, 33 were evaluable for efficacy. Dose-limiting toxicities were prolonged-QTc and nausea at DL3. Adverse events included fatigue and nausea (grades 1-3), and rash and anorexia (grades 1-2). Disease control rates were 54% for NSCLC (n = 26) and 43% for head and neck cancer (n = 7). Of 7 patients with NSCLC with EGF receptor (EGFR) mutations, 3 had partial response, 3 had stable disease, and 1 progressed. For EGFR-mutant versus EGFR wild-type patients, progression-free survival (PFS) was 4.7 versus 1.9 months (P = 0.43) and overall survival was 41 (estimated) versus 5.2 months (P = 0.39). Erlotinib pharmacokinetics was not significantly affected. Correlative studies confirmed panobinostat's pharmacodynamic effect in blood, FPB, and tumor samples. Low CHK1 expression levels correlated with PFS (P = 0.006) and response (P = 0.02). We determined MTD at 30 mg (panobinostat) and 100 mg (erlotinib). Further studies are needed to further explore the benefits of HDAC inhibitors in patients with EGFR-mutant NSCLC, investigate FPB as a potential surrogate source for biomarker investigations, and validate CHK1's predictive role. ©2014 AACR.

DNA damage response in renal ischemia-reperfusion and ATP-depletion injury of renal tubular cells

PubMed Central

Ma, Zhengwei; Wei, Qingqing; Dong, Guie; Huo, Yuqing; Dong, Zheng

2014-01-01

Renal ischemia-reperfusion leads to acute kidney injury (AKI) that is characterized pathologically by tubular damage and cell death, followed by tubular repair, atrophy and interstitial fibrosis. Recent work suggested the possible presence of DNA damage response (DDR) in AKI. However, the evidence is sketchy and the role and regulation of DDR in ischemic AKI remain elusive. In this study, we demonstrated the induction of phosphorylation of ATM, H2AX, Chk2 and p53 during renal ischemia-reperfusion in mice, suggesting DDR in kidney tissues. DDR was also induced in vitro during the recovery or “reperfusion” of renal proximal tubular cells (RPTCs) after ATP-depletion. DDR in RPTCs was abrogated by supplying glucose to maintain ATP via glycolysis, indicating that the DDR depends on ATP depletion. The DDR was also suppressed by the general caspase inhibitor z-VAD and the overexpression of Bcl-2, supporting a role of apoptosis-associated DNA damage in the DDR. N-acetylcysteine (NAC), an antioxidant, suppressed the phosphorylation of ATM and p53 and, to a less extent, Chk2, but NAC increased the phosphorylation and nuclear foci formation of H2AX. Interestingly, NAC increased apoptosis, which may account for the observed H2AX activation. Ku55933, an ATM inhibitor, blocked ATM phosphorylation and ameliorated the phosphorylation of Chk2 and p53, but it increased H2AX phosphorylation and nuclear foci formation. Ku55933 also increased apoptosis in RPTCs following ATP-depletion. The results suggest that DDR occurs during renal ischemia-reperfusion in vivo and ATP-depletion injury in vitro. The DDR is partially induced by apoptosis and oxidative stress-related DNA damage. ATM, as a sensor in the DDR, may play a cytoprotective role against tubular cell injury and death. PMID:24726884

Verbal Modification via Visual Display

ERIC Educational Resources Information Center

Richmond, Edmun B.; Wallace-Childers, La Donna

1977-01-01

The inability of foreign language students to produce acceptable approximations of new vowel sounds initiated a study to devise a real-time visual display system whereby the students could match vowel production to a visual pedagogical model. The system used amateur radio equipment and a standard oscilloscope. (CHK)

Malice in Wonderland: The Linguist's Future in the German Department

ERIC Educational Resources Information Center

Markey, T. L.

1977-01-01

Suggests a tripartite division of instructional duties in college language departments: (1) language instruction on intermediate and advanced levels, (2) tutorial instruction, and (3) interdisciplinary courses to curtail compartmentalization and encourage cultural comparison. Linguist and literary scholar need not be at odds. (CHK)

Teacher-Training Projects

ERIC Educational Resources Information Center

Greer, Leslie

1977-01-01

The Sociedade Brasileira de Cultura Inglesa of Sao Paolo, Brazil, is an English teaching center which also runs an introductory course to train teachers of English. This article describes some of the projects completed by prospective teachers; they include language games, pictures, cartoons, role-playing and writing creative dialogue. (CHK)

Plasticity in Memorial Networks

ERIC Educational Resources Information Center

Hayes-Roth, Barbara; Hayes-Roth, Frederick

1975-01-01

An adaptive network model is proposed to represent the structure and processing of knowledge. Accessibility of subjects' stored information was measured. Relationships exist among (a) frequency of verifying a test relation, (b) other relations involving concepts used to evaluate test relation, (c) frequency of verifying those relations. (CHK)

Free Recall Curves: Nothing but Rehearsing Some Items More or Recalling Them Sooner?

ERIC Educational Resources Information Center

Brodie, Delbert A.; Prytulak, Lubomir S.

1975-01-01

The hypothesis that free recall curves reflecting effects of serial position, presentation time and delay of recall are attributable to subjects' pattern of rehearsal was explored. Experiments varied the patterns of rehearsal to examine the effects on recall. (CHK)

Alcohol and Memory: Storage and State Dependency

ERIC Educational Resources Information Center

Parker, Elizabeth S.; And Others

1976-01-01

Effects of acute alcohol intoxication on the storage phase of memory were evaluated with two tasks that minimized response retrieval: unpaced paired-associate learning with highly available responses and forced-choice picture recognition. It was concluded that storage processes are sensitive to disruption by alcohol. (CHK)

Teaching Oral Chinese in the United States

ERIC Educational Resources Information Center

Cheng, Chin-Chuan

1976-01-01

Because Chinese language textbooks were judged inadequate in teaching vocabulary dealing with everyday life in the U.S. and in China, new methods and materials were introduced into an oral Chinese course. Prepared discussion topics, Chinese films, soap operas, and shortwave radio broadcasts were used. (CHK)

Chk1 and Wee1 kinases coordinate DNA replication, chromosome condensation, and anaphase entry

PubMed Central

Fasulo, Barbara; Koyama, Carol; Yu, Kristina R.; Homola, Ellen M.; Hsieh, Tao S.; Campbell, Shelagh D.; Sullivan, William

2012-01-01

Defects in DNA replication and chromosome condensation are common phenotypes in cancer cells. A link between replication and condensation has been established, but little is known about the role of checkpoints in monitoring chromosome condensation. We investigate this function by live analysis, using the rapid division cycles in the early Drosophila embryo. We find that S-phase and topoisomerase inhibitors delay both the initiation and the rate of chromosome condensation. These cell cycle delays are mediated by the cell cycle kinases chk1 and wee1. Inhibitors that cause severe defects in chromosome condensation and congression on the metaphase plate result in delayed anaphase entry. These delays are mediated by wee1 and are not the result of spindle assembly checkpoint activation. In addition, we provide the first detailed live analysis of the direct effect of widely used anticancer agents (aclarubicin, ICRF-193, VM26, doxorubicin, camptothecin, aphidicolin, hydroxyurea, cisplatin, mechlorethamine and x-rays) on key nuclear and cytoplasmic cell cycle events. PMID:22262459

Teacher Training Once More: Some Respectful Onjections

ERIC Educational Resources Information Center

Sammons, Jeffrey L.

1976-01-01

Argues that the Teaching Assistant system should be dismantled on the grounds that it is unethical, educationally unsound, and increasingly disruptive of the welfare and purposes of the teaching profession. Experienced assistant professors and tenured faculty should teach, assisted by a handful of well-supervised TA's. (CHK)

The Evolution of the Language Laboratory: Changes During Fifteen Years of Operation

ERIC Educational Resources Information Center

Stack, Edward M.

1977-01-01

This article summarizes conditions and changes in language laboratories. Types of laboratories and equipment are listed; laboratory personnel include technicians, librarians and student assistants. Most maintenance was done by institution personnel; student use is outlined. Professional attitudes and equipment statistics are surveyed. (CHK)

Comparision between bed side testing of blood glucose by glucometer vs centralized testing in a tertiary care hospital.

PubMed

Baig, Ayaz; Siddiqui, Imran; Jabbar, Abdul; Azam, Syed Iqbal; Sabir, Salman; Alam, Shahryar; Ghani, Farooq

2007-01-01

To determine the accuracy, turnaround time and cost effectiveness of bedside monitoring of blood glucose levels by non-laboratory health care workers and centralized testing of blood glucose by automated analyzer in a tertiary care hospital. The study was conducted in Section of Chemical Pathology, Department of Pathology and Microbiology and Section of Endocrinology Department of Medicine, Aga Khan University and Hospital Karachi, from April 2005 to March 2006. One hundred and ten patients were included in the study. The blood glucose levels were analyzed on glucometer (Precision Abbott) by finger stick, using Biosensor Technology. At the same time venous blood was obtained to analyze glucose in clinical laboratory on automated analyzer (SYNCHRON CX7) by glucose oxidase method. We observed good correlation between bed side glucometer and laboratory automated analyzer for glucose values between 3.3 mmol/L (60 mg/dl) and 16.7 (300 mg/dl). A significant difference was observed for glucose values less than 3.3 mmol/L (p = 0.002) and glucose values more than 16.67 mmol/l (p = 0.049). Mean Turnaround time for glucometer and automated analyzer were 0.08 hours and 2.49 hours respectively. The cost of glucose testing with glucometer was 48.8% lower than centralized lab based testing. Bedside glucometer testing, though less expensive does not have good accuracy in acutely ill patient with either very high or very low blood glucose levels.

E-Waste Driven Pollution in Pakistan: The First Evidence of Environmental and Human Exposure to Flame Retardants (FRs) in Karachi City.

PubMed

Iqbal, Mehreen; Syed, Jabir Hussain; Breivik, Knut; Chaudhry, Muhammad Jamshed Iqbal; Li, Jun; Zhang, Gan; Malik, Riffat Naseem

2017-12-05

Informal e-waste recycling activities have been shown to be a major emitter of organic flame retardants (FRs), contributing to both environmental and human exposure to laborers at e-waste recycling sites in some West African countries, as well as in China and India. The main objective of this study was to determine the levels of selected organic FRs in both air and soil samples collected from areas with intensive informal e-waste recycling activities in Karachi, Pakistan. Dechlorane Plus (DP) and "novel" brominated flame retardants (NBFRs) were often detected in high concentrations in soils, while phosphorus-based FRs (OPFRs) dominated atmospheric samples. Among individual substances and substance groups, decabromodiphenyl ether (BDE-209) (726 ng/g), decabromodiphenyl ethane (DBDPE) (551 ng/g), 1,2-bis(2,4,6-tribromophenoxy) ethane (BTBPE) (362 ng/g), and triphenyl-phosphate (∑TPP) (296 ng/g) were found to be prevalent in soils, while OPFR congeners (5903-24986 ng/m 3 ) were prevalent in air. The two major e-waste recycling areas (Shershah and Lyari) were highly contaminated with FRs, suggesting informal e-waste recycling activities as a major emission source of FRs in the environment in Karachi City. However, the hazards associated with exposure to PM 2.5 appear to exceed those attributed to exposure to selected FRs via inhalation and soil ingestion.

Comparison of knowledge, attitude and practices of betelnut users in two socio-economic areas of Karachi.

PubMed

Khan, Muhammad Shahzeb; Bawany, Faizan Imran; Shah, Syed Raza; Hussain, Mehwish; Arshad, Mohammad Hussham; Nisar, Nighat

2013-10-01

To gain an insight on the knowledge, attitude and practices of those who chew betel nut in two different socioeconomic regions of Karachi. The cross-sectional study was conducted in Saddar and Defence areas of Karachi over a five-week period in March-April 2012. Individual interviews following verbal consent were conducted using a pre-coded questionnaire, which was divided into 3 sections to analyse the knowledge, attitude and practices of the chewers. The data was entered and analysed using SPSS v. 16.0. Pearson's chi-square was used as the primary statistical test. A total of 370 subjects, 185 (50%) from each area, comprised the study. Majority of the chewers in Defence had higher educational qualification and income. Most of the participants in both areas acknowledged that betel nut chewing can potentially result in mouth (n = 274; 74.1%) and throat cancers (n = 267; 72.2%). A large part of the sample (n = 299; 80.8%) conceded that betel nut chewing is a bad habit, and almost half the sample was addicted to it (n = 194; 52.4%). Awareness regarding the detrimental effects of betel nut was satisfactory amongst the subjects, but the population was not willing to quit the habit. We recommend a two-pronged approach, offering widespread educational and awareness campaigns to prevent increased consumption of betel nuts, and professional counselling services for those already addicted.

Study on awareness of osteoporosis and its associated risk factors among housewives and working women in Karachi.

PubMed

Raza, Lubna; Ahmed, Anzar; Kumar, Vinod; Hasnain, Abid

2017-12-01

To compare awareness of osteoporosis and its associated risks among working women and housewives. This cross-sectional study was conducted at Karachi University and Dow University of Health Sciences, Karachi, from January to April 2015, and comprised working women and housewives who were enrolled using convenience sampling. Data was collected on awareness, dairy, fruit, vegetable, poultry/fish consumption as well as exercise, diagnosis and treatment taken for deficiency of vitamin D. Weight, height and body mass index were noted. Analysis was done using SPSS 17. Of the 600 participants, 300(50%) were housewives and 300(50%) were working women. Significant differences were observed in marriage years, number of children and income (p <0.05). Body mass index of groups demonstrated that more working women were within normal range weight than housewives (p<0.05). Fewer housewives had awareness about osteoporosis and the majority of them had a sedentary lifestyle (p<0.001). More housewives were diagnosed with vitamin D deficiency and were prescribed for treatment (p<0.001). Dairy and vegetable consumption was found comparable while fruits and poultry/ fish intake was better in working women (p<0.05). Since the subjects in both groups had no regular exercise programme, therefore the overall results were insignificant (p>0.05). Greater number of working women had awareness of osteoporosis.

The common causes leading to pancytopenia in patients presenting to tertiary care hospital.

PubMed

Das Makheja, Kirpal; Kumar Maheshwari, Bharat; Arain, Shafique; Kumar, Suneel; Kumari, Sangeeta; Vikash

2013-09-01

The objective of this study was to determine the frequency of common causes leading to Pancytopenia in patients presenting to tertiary care hospital at Karachi. A total of 62 patients with the diagnosis of Pancytopenia of more than one week duration were enrolled in the study. All patients underwent a detailed medical history and full physical examination followed by blood sampling for the investigations i.e. complete blood count with peripheral film, erythrocyte sedimentation rate (ESR), Malarial parasites (MP), liver function test, Renal function tests, PT and viral profile (HBsAg, Anti-HCV), Ultrasonography of abdomen. All patients underwent bone marrow aspiration and trephine biopsy for reporting and interpretation. Duration of study was six months, from May 2010 to November 2010. The average age of the patients was 37.76 ± 16.38years. Out of 62 patients, 36 (58%) were male and 26 (42%) were female. Megaloblastic anemia was the commonest cause that was observed in 41.9% cases followed by acute myeloid leukemia 27.4%, aplastic anemia 19.4% and erythroid hyperplasia 11.3%. Conclusion : This study concluded that most common cause of pancytopenia is Megaloblastic anemia, followed by acute myeloid leukemia and aplastic anemia. Bone marrow examination is a single useful investigation which reveals the underlying cause in patients with pancytopenia.

Le Septieme Art: An Introduction to Foreign Films for Sixth-Formers

ERIC Educational Resources Information Center

Beaton, Richard

1977-01-01

A foreign film course covering two days is described. A variety of films were available for students' choice, and all involved a particular theme. Films for French, German, and Spanish courses are listed. A schedule for individual, group and whole course work and discussion is presented. (CHK)

The Place of Foreign Languages in a Curriculum for Liberal Education

ERIC Educational Resources Information Center

Moravcsik, Julius; Juilland, Alphonse

1977-01-01

The study of foreign languages in the liberal arts curriculum is defended. Foreign languages reveal the rules characterizing cognitive human activities; they help us to understand both common bonds of humanity and varieties of human behavior. Language study should be central to humanities study. (CHK)

Storage and Retrieval Changes that Occur in the Development and Release of PI

ERIC Educational Resources Information Center

Chechile, Richard; Butler, Keith

1975-01-01

A Bayesian statistical procedure separating storage from retrieval was used to study development and release of proactive interference in the Brown-Peterson paradigm. A theory of PI is developed stressing response competition at test time and interference in transfer between short- and long-term memory. (CHK)

Sensory and Cognitive Determinants of Reading Speed

ERIC Educational Resources Information Center

Jackson, Mark D.; McClelland, James L.

1975-01-01

Fast and average readers were tested on four tasks. Fast readers appear to pick up more information per fixation on structured textual material, and had a greater span of apprehension for unrelated elements. Results disagree with the view that reading speed depends solely on ability to infer missing information. (CHK)

Apuntes sobre Latinismos en Espanol (Notes on Latinisms in Spanish)

ERIC Educational Resources Information Center

Perez B., L. A.

1977-01-01

Several Latinisms appear in Latin American Spanish, which would logically be farther from its Latin roots than Spanish in Spain. The existence of these elements and their importance as linguistic facts is analyzed here. Four words are treated: "Cliente,""cuadrar,""cuarto" and "rabula." (Text is in Spanish.) (CHK)

The Ranschburg Effect: Tests of the Guessing-Bias and Proactive Interference Hypotheses

ERIC Educational Resources Information Center

Walsh, Michael F.; Schwartz, Marian

1977-01-01

The guessing-bias and proactive interference hypotheses of the Ranschburg Effect were investigated by giving three groups different instructions as to guessing during recall. Results failed to support the prediction that the effect should be reduced or eliminated on shift trials. Neither hypothesis received significant support. (CHK)

Una miscelanea de refranes espanoles raros, curiosos, y jocosos (A Miscellany of Rare, Curious and Humorous Spanish Proverbs).

ERIC Educational Resources Information Center

Hayes, Francis

This listing of unusual Spanish proverbs contains words of wisdom on money, doctors, agriculture, students, procrastination, pessimism, war, good and evil, religion, God, and a host of other topics. The topic of each proverb is given in English. (CHK)

Reading While Listening: A Linear Model of Selective Attention

ERIC Educational Resources Information Center

Martin, Maryanne

1977-01-01

Two experiments are described. One measured performance of subjects on pairs of concurrent verbal tasks, monitoring sentences for certain items while reading. Secondary task performance combined with a primary task is proportional to its performance in isolation. The second experiment checked certain results of the first. (CHK)

Biological Analogs for Language Contact Situations

ERIC Educational Resources Information Center

Seliger, Herbert W.

1977-01-01

This article proposes that language contact can be best understood if the entire range of such situations from second language learning to evolution of dialects and creoles is studied within a framework analogical to the symbiosis of living organisms. Language contact is viewed in terms of dynamic evolutionary stages. (CHK)

An Interdisciplinary Approach to the Teaching of Foreign Literature

ERIC Educational Resources Information Center

Davidheiser, James C.

1977-01-01

The Integrated Learning Semester program at the University of Delaware is described. Courses were designed around themes touching several academic areas and instructors cooperated in teaching courses. A course in literature and music of Romanticism is outlined and specific problems and procedures for implementing a program are noted. (CHK)

Exploring Fathers’ Role in Breastfeeding Practices in the Urban and Semiurban Settings of Karachi, Pakistan

PubMed Central

Mithani, Yasmin; Premani, Zahra Shaheen; Kurji, Zohra; Rashid, Shehnaz

2015-01-01

ABSTRACT This study explored fathers’ perceptions about breastfeeding infants. A qualitative exploratory study design was used. Study setting was urban and semiurban areas of Karachi, Pakistan. In-depth interviews were conducted with 12 fathers. The following themes emerged from the data collected: knowledge and awareness and enabling and impeding factors. Most fathers seemed eager to get involved and assist their partners in proper breastfeeding practices because they believed that doing so is in accordance with their faith. Fathers felt that adequate support from their family members and employers could enable them to encourage their partners to initiate and maintain exclusive and optimum breastfeeding practices. Exploring fathers’ perception regarding breastfeeding in the context of Pakistan is still a new field of study. PMID:26834446

Patho-epidemiology of Cancer Cervix in Karachi South.

PubMed

Bhurgri, Yasmin; Nazir, Kauser; Shaheen, Yasmeen; Usman, Ahmed; Faridi, Naveen; Bhurgri, Hadi; Malik, Jawaid; Bashir, Imtiaz; Bhurgri, Asif; Kayani, Naila; Pervez, Shahid; Hasan, Sheema H; Setna, Faridoon; Zaidi, S M H

2007-01-01

The present study was conducted with the objective of examining descriptive epidemiological and pathological characteristics of cancer cervix in Karachi South, an all urban district population of Karachi, Pakistan. A total of 74 cases of cancer cervix, ICD-10 (International Classification of Diseases 10th Revision) category C53 were registered at the Karachi Cancer Registry, for Karachi South, during a 3 year period, 1st January, 1995 to 31st December 1997. The age standardized incidence rate (ASR) world and crude incidence rate (CIR) per 100,000 were 6.81 (5.2, 8.43) and 3.22 (2.49 to 3.96). Cancer cervix accounted for approximately 3.6% of all cancers in females and was the sixth malignancy in hierarchy. The mean age of the cancer cases was 53.27 years [standard deviation (SD) 11.6; 95% confidence interval (CI) 50.58, 55.96; range (R) 32-85 years)]. The distribution by religion was Muslims (90.5%), Christians (8.1%) and Hindus (1.4%). There were no cases reported in Parsees. The frequency distribution by ethnicity was Urdu speaking Mohajirs (20.3%), Punjabis (17.6%), Gujrati speaking Mohajirs (4.1%), memon Mohajirs (8.1%), Sindhis (10.8%), Baluchs (8.1%), Pathans (5.4%) and Afghan migrants (2.7%). The ethnicity was not known in approximately a fourth (23.0%) of the cases. The socio-economic distribution was 27.0% financially deprived class, 24.4% lower middle class and 48.7% upper middle and affluent classes. The majority of the women were married (86.5%); a smaller number were unmarried (2.7%) or widows (10.8%). The age-specific curves showed a gradual increase in risk from the fourth up till the seventh decade, followed by an actual apparent decrease in risk after 64 years of age. The peak incidence was observed in the 60-64 year age group. The morphological categorization was squamous cell carcinoma (86.5%), adenocarcinoma (10.9%) and adenosquamous carcinoma (2.6%). The majority of cases presented with moderately differentiated or grade 2 lesions (45.9%). There were no in-situ cases. Approximately half the cancers (58.1%) had spread regionally and 8.1% to a distant site at the time of diagnosis. Odds ratios (OR) were calculated for socioeconomic residential categories, religion, ethnicity, age groups and education. The OR for socioeconomic residential categories ranged between 0.69 and 2.9 with a marginally higher risk in the lower [OR 2.09 (95% CI .97; 4.49)] and lower middle class [OR 2.08 (95%CI 0.95; 4.58)]. Hindus [OR 1.2 (95% CI 0.18; 2.2)] had a slightly higher risk then the Muslims [OR 0.14 (95% CI 0.17; 1.2)]. A higher risk was also observed for Christians [OR 7.76 (95% CI 1.74; 34.5)]. The incidence of cervical cancer in Karachi South (1995-97) reflects a low risk population with a late presentation and a high stage disease at presentation. It is suggested that cervical screening if implemented should focus on once a life time methodology involving 36-45 year old women. This should be combined with HPV vaccination for the young and public health education for all. A regular cervical screening program would require mobilization of considerable financial, structural and human resources along with training for personnel. This may burden the already stretched health resources of a developing country.

Equitable access to comprehensive surgical care: the potential of indigenous private philanthropy in low-income settings.

PubMed

Samad, Lubna; Iqbal, Mehreen; Tariq, Ahson; Shahzad, Wasif; Khan, Aamir J

2015-01-01

Equitable access to surgical care is necessary for improving global health. We report on the performance, financial sustainability, and policy impact of a free-of-cost multispecialty surgical delivery program in Karachi, Pakistan built upon local private philanthropy. We evaluated trends in surgical service delivery, expenditures, and philanthropic donations from Indus Hospital's first 5 years of operation (2007-2012), projected these over the hospital's current expansion phase, compared these to publicly accessible records of other philanthropic hospitals providing surgical care, and documented the government's evolving policies toward this model. Between 2007 and 2012, Indus Hospital treated 40,012 in-patients free of cost, 33,606 (84 %) of them for surgical procedures. Surgical procedures increased fivefold to 9,478 during 2011-2012 from 1,838 during 2007-2008. Bed occupancy increased to 91 % from 65 % over the same period. External surgical missions accounted for less than 0.5 % of patients served. Ninety-eight percent (98 %) of all philanthropic donations--totaling USD 26.6 million over 2007-2012--were locally generated. Zakat (obligatory annual religious alms in the Islamic faith) constituted 34 % of all donations, followed by unrestricted funds (24 %) and donations-in-kind (24 %), buildings (12 %), grants (5 %), and return on investments (1 %). Overall, donations received between 2007 and 2012 increased sevenfold, with Zakat increasing 12-fold. During 2013-2014, the Government of Pakistan provided land lease and annual operational grants totaling USD 9 million. Local philanthropy can sustain and grow the provision of free, high-quality surgical care in low-income settings, and encourage the development of hybrid government-philanthropic models of surgical care.

Barriers and perceptions regarding code status discussion with families of critically ill patients in a tertiary care hospital of a developing country: A cross-sectional study.

PubMed

Syed, Ahsan A; Almas, Aysha; Naeem, Quratulain; Malik, Umer F; Muhammad, Tariq

2017-02-01

In Asian societies including Pakistan, a complex background of illiteracy, different familial dynamics, lack of patient's autonomy, religious beliefs, and financial constraints give new dimensions to code status discussion. Barriers faced by physicians during code status discussion in these societies are largely unknown. To determine the barriers and perceptions in discussion of code status by physicians. Questionnaire-based cross-sectional study. This study was conducted in the Department of Medicine of The Aga Khan University Hospital, Karachi, Pakistan. A total of 134 physicians who had discussed at least five code statuses in their lifetime were included. A total of 77 (57.4%) physicians responded. Family-related barriers were found to be the most common barriers. They include family denial (74.0%), level of education of family (66.2%), and conflict between individual family members (66.2%). Regarding personal barriers, lack of knowledge regarding prognosis (44.1%), personal discomfort in discussing death (29.8%), and fear of legal consequences (28.5%) were the top most barriers. In hospital-related barriers, time constraint (57.1%), lack of hospital administration support (48.0%), and suboptimal nursing care after do not resuscitate (48.0%) were the most frequent. There were significant differences among opinions of trainees when compared to those of attending physicians. Family-related barriers are the most frequent roadblocks in the end-of-life care discussions for physicians in Pakistan. Strengthening communication skills of physicians and family education are the potential strategies to improve end-of-life care. Large multi-center studies are needed to better understand the barriers of code status discussion in developing countries.

Kirschner wire pin tract infection rates between percutaneous and buried wires in treating metacarpal and phalangeal fractures.

PubMed

Rafique, Atif; Ghani, Shahab; Sadiq, Moiz; Siddiqui, Intisar Ahmed

2006-08-01

To compare pin tract infection rate between percutaneous and buried placement of Kirschner (K-) wiring for hand fractures. Quasi--experimental study. Plastic, Reconstructive, Hand and Burn Surgery Unit, Liaquat National Hospital, Karachi, from September 2005--February 2006. Patients with fractures of metacarpals and phalanges of hand were selected by non-probability purposive method. Assessment of pin tract infection by clinical examination and pin tract scoring was done by modification of Oppenheim classification. Statistical analysis was done using Chi-square test. Ten out of 55 percutaneous and 2 out of 45 buried wires were infected. The difference in infection rates of two groups was statistically significant at p<0.05. Three percutaneous, but not buried Kirschner wires, had to be removed before 4 weeks because of failure to respond to local wound care and oral antibiotics. Percutaneous K- wires had significantly greater infection rate than wires which were buried deep to the skin.

Patient communication in radiology: current status of breaking bad news among radiologists and radiology trainees in Pakistan.

PubMed

Ali Khawaja, Ranish Deedar; Akhtar, Waseem; Khawaja, Ali; Irfan, Hira; Naeem, Mohammad; Memon, Mukhtiar

2013-10-01

Breaking bad news can be an intimidating task for any physician. The aim of this study was to record the practices of breaking bad news to the patients by Pakistani radiologists and trainees. The radiologists and trainees attending the 26th National Radiological Conference in October 2010 in Karachi, Pakistan, were surveyed. The response rate was 76%. The respondents included residents (51%), private practicing radiologists (28%), academic radiologists (13%), and other trainees (8%). Most of the academic radiologists communicated with their patients. The daily frequency of breaking bad news by residents was noted, which was highest in the public teaching hospitals (71%). For severe abnormalities such as malignancy, 50% residents, 55% of the academic radiologists and 74% of the private practicing radiologists were very uncomfortable in disclosure of results. Differences in frequency of communication with patients were noticed with both different training levels, and different settings of practice in a developing country.

PREFACE: 1st International Conference on Sensing for Industry, Control, Communication & Security Technologies

NASA Astrophysics Data System (ADS)

Shuja Syed, Ahmed

2013-12-01

The 1st International Conference on Sensing for Industry, Control, Communication & Security Technologies (ICSICCST-2013), took place in Karachi, Pakistan, from 24-26 June 2013. It was organized by Indus University, Karachi, in collaboration with HEJ Research Institute of Chemistry, University of Karachi, Karachi. More than 80 abstracts were submitted to the conference and were double blind-reviewed by an international scientific committee. The topics of the Conference were: Video, Image & Voice Sensing Sensing for Industry, Environment, and Health Automation and Controls Laser Sensors and Systems Displays for Innovative Applications Emerging Technologies Unmanned, Robotic, and Layered Systems Sensing for Defense, Homeland Security, and Law Enforcement The title of the conference, 'Sensing for Industry, Control, Communication & Security Technologies' is very apt in capturing the main issues facing the industry of Pakistan and the world. We believe the sensing industry, particularly in Pakistan, is currently at a critical juncture of its development. The future of the industry will depend on how the industry players choose to respond to the challenge of global competition and opportunities arising from strong growth in the Asian region for which we are pleased to note that the conference covered a comprehensive spectrum of issues with an international perspective. This will certainly assist industry players to make informed decisions in shaping the future of the industry. The conference gathered qualified researchers from developed countries like USA, UK, Sweden, Saudi Arabia, China, South Korea and Malaysia etc whose expertise resulting from the research can be drawn upon to build an exploitable area of new technology that has potential Defense, Homeland Security, and Military applicability. More than 250 researchers/students attended the event and made the event great success as the turnout was 100%. An exceptional line-up of speakers spoke at the occasion. We want to thank the Organizing Committee, the Institutions and Sponsors supporting the Conference, especially 'Centre for Emerging Sciences, Engineering & Technology (CESET), Islamabad', the IOP Publishers and everyone who contributed to the organization of this meeting, for their invaluable efforts to make this event a great success. Professor Dr Ahmed Shuja Syed Chief Editor The PDF also contains lists of the boards, committees and sponsors.

Intercomparison of MODIS, MISR, OMI, and CALIPSO aerosol optical depth retrievals for four locations on the Indo-Gangetic plains and validation against AERONET data

NASA Astrophysics Data System (ADS)

Bibi, Humera; Alam, Khan; Chishtie, Farrukh; Bibi, Samina; Shahid, Imran; Blaschke, Thomas

2015-06-01

This study provides an intercomparison of aerosol optical depth (AOD) retrievals from satellite-based Moderate Resolution Imaging Spectroradiometer (MODIS), Multiangle Imaging Spectroradiometer (MISR), Ozone Monitoring Instrument (OMI), and Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) instrumentation over Karachi, Lahore, Jaipur, and Kanpur between 2007 and 2013, with validation against AOD observations from the ground-based Aerosol Robotic Network (AERONET). Both MODIS Deep Blue (MODISDB) and MODIS Standard (MODISSTD) products were compared with the AERONET products. The MODISSTD-AERONET comparisons revealed a high degree of correlation for the four investigated sites at Karachi, Lahore, Jaipur, and Kanpur, the MODISDB-AERONET comparisons revealed even better correlations, and the MISR-AERONET comparisons also indicated strong correlations, as did the OMI-AERONET comparisons, while the CALIPSO-AERONET comparisons revealed only poor correlations due to the limited number of data points available. We also computed figures for root mean square error (RMSE), mean absolute error (MAE) and root mean bias (RMB). Using AERONET data to validate MODISSTD, MODISDB, MISR, OMI, and CALIPSO data revealed that MODISSTD data was more accurate over vegetated locations than over un-vegetated locations, while MISR data was more accurate over areas close to the ocean than over other areas. The MISR instrument performed better than the other instruments over Karachi and Kanpur, while the MODISSTD AOD retrievals were better than those from the other instruments over Lahore and Jaipur. We also computed the expected error bounds (EEBs) for both MODIS retrievals and found that MODISSTD consistently outperformed MODISDB in all of the investigated areas. High AOD values were observed by the MODISSTD, MODISDB, MISR, and OMI instruments during the summer months (April-August); these ranged from 0.32 to 0.78, possibly due to human activity and biomass burning. In contrast, high AOD values were observed by the CALIPSO instrument between September and December, due to high concentrations of smoke and soot aerosols. The variable monthly AOD figures obtained with different sensors indicate overestimation by MODISSTD, MODISDB, OMI, and CALIPSO instruments over Karachi, Lahore, Jaipur and Kanpur, relative to the AERONET data, but underestimation by the MISR instrument.

Importancia de la traduccion (The Importance of Translation)

ERIC Educational Resources Information Center

Garcia Yebra, Valentin

1975-01-01

This article emphasizes the cultural importance of activities furthering good translation. The value of a translated work rests as much on the skill of the translator as on the original author. Translation is important to Spain in order for the country to raise its cultural and economic level. (Text is in Spanish.) (CHK)

Where Does Latin "Sum" Come From?

ERIC Educational Resources Information Center

Nyman, Martti A.

1977-01-01

The derivation of Latin "sum,""es(s),""est" from Indo-European "esmi,""est,""esti" involves methodological problems. It is claimed here that the development of "sum" from "esmi" is related to the origin of the variation "est-st" (less than"esti"). The study is primarily concerned with this process, but chronological suggestions are also made. (CHK)

Contextual Factors in the Use of the Present Perfect

ERIC Educational Resources Information Center

Moy, Raymond H.

1977-01-01

In this study the inadequacies of rules governing the present perfect in isolated sentences are discussed and then two contextual factors thought to be connected with current relevance and the use of the present perfect are described. These factors are experimentally shown to influence use of the present perfect significantly. (CHK)

Competition Processes and Proactive Interference in Short-Term Memory

ERIC Educational Resources Information Center

Bennett, Raymond W.; Kurzeja, Paul L.

1976-01-01

In an experiment using single-word items, subjects are run under three different speed-accuracy trade-off conditions. A competition model would predict that when subjects are forced to respond quickly, there will be an increase in errors, and these will be from recent past items. The prediction was confirmed. (CHK)

Some Adjectival Nominalizations in English

ERIC Educational Resources Information Center

Bowers, John S.

1975-01-01

This paper concludes that there is evidence in favor of handling the derived nominals of Predicate AP's with a lexicalist theory, in conjunction with a base schema of the form (1)-(2). The transformation NP-Postposing is proposed to explain variations. (Available from North-Holland Publishing Co., P. O. Box 211, Amsterdam, The Netherlands.) (CHK)

77 FR 18833 - Government-Owned Inventions; Availability for Licensing

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-28

... mass spectra obtained and reproduced for food-borne pathogens. Unique DISI device with gas cylinder... With a Small Molecule CHK2 Inhibitor Description of Technology: DNA damage sensors such as Checkpoint... in response to DNA damage. It has been reported that these DNA damage sensors also play a key role in...

La ensenanza de idiomas en Puerto Rico (Language Teaching in Puerto Rico)

ERIC Educational Resources Information Center

Llorens, Washington

1976-01-01

The poor command of Spanish common to many Puerto Ricans is due, not to the teaching of English as a second language, but to the poor instruction of the native language and the lack of emphasis on reading good Spanish literature. The two languages can coexist. (Text is in Spanish.) (CHK)

Memory for Nonsemantic Attributes of American Sign Language Signs and English Words

ERIC Educational Resources Information Center

Siple, Patricia

1977-01-01

Two recognition memory experiments were used to study the retention of language and modality of input. A bilingual list of American Sign Language signs and English words was presented to two deaf and two hearing groups, one instructed to remember mode of input, and one hearing group. Findings are analyzed. (CHK)

Order and Position in Primary Memory for Letter Strings

ERIC Educational Resources Information Center

Lee, Catherine L.; Estes, William K.

1977-01-01

A short-term recall task in which letters were spaced in different ways by distractor digits was used to separate aspects of primary and secondary memory processes and to permit examination of primary memory for position, order and item independently. Memory for order appeared derivative to memory for temporal position. (CHK)

A New Perspective on Teamwork in Teaching: A Report on German Lectures in the Biological Sciences

ERIC Educational Resources Information Center

Brancaforte, Charlotte; And Others

1976-01-01

A university German department cooperated with the Zoology Department to offer a series of 13 lectures in biology, delivered in German by university scientists on their fields of research. This report discusses the background and atmosphere of the project, evaluates its effects and suggests improvements. (CHK)

Functional Analysis of Chk2-Kiaa0170 Interaction

DTIC Science & Technology

2005-09-01

R., Hollestelle, A., Houben, M., Crepin, E., van Veghel-Plandsoen, M., et al. (2002). Low-penetrance susceptibility to breast cancer due to CHEK2 (*)1...K., Heikkila, P., et al. (2002). A CHEK2 genetic variant contributing to a substantial fraction of familial breast cancer. Am J Hum Genet 71, 432-438

Dietary flavonoid derivatives enhance chemotherapeutic effect by inhibiting the DNA damage response pathway.

PubMed

Kuo, Ching-Ying; Zupkó, István; Chang, Fang-Rong; Hunyadi, Attila; Wu, Chin-Chung; Weng, Teng-Song; Wang, Hui-Chun

2016-11-15

Flavonoids are the most common group of polyphenolic compounds and abundant in dietary fruits and vegetables. Diet high in vegetables or dietary flavonoid supplements is associated with reduced mortality rate for patients with breast cancer. Many studies have been proposed for mechanisms linking flavonoids to improving chemotherapy efficacy in many types of cancers, but data on this issue is still limited. Herein, we report on a new mechanism through which dietary flavonoids inhibit DNA damage checkpoints and repair pathways. We found that dietary flavonoids could inhibit Chk1 phosphorylation and decrease clonogenic cell growth once breast cancer cells receive ultraviolet irradiation, cisplatin, or etoposide treatment. Since the ATR-Chk1 pathway mainly involves response to DNA replication stress, we propose that flavonoid derivatives reduce the side effect of chemotherapy by improving the sensitivity of cycling cells. Therefore, we propose that increasing intake of common dietary flavonoids is beneficial to breast cancer patients who are receiving DNA-damaging chemotherapy, such as cisplatin or etoposide-based therapy. Copyright © 2016 Elsevier Inc. All rights reserved.

Sarsaparilla (Smilax Glabra Rhizome) Extract Activates Redox-Dependent ATM/ATR Pathway to Inhibit Cancer Cell Growth by S Phase Arrest, Apoptosis, and Autophagy.

PubMed

She, Tiantian; Feng, Junnan; Lian, Shenyi; Li, Ruobing; Zhao, Chuanke; Song, Guoliang; Luo, Jie; Dawuti, Rouxianguli; Cai, Shaoqing; Qu, Like; Shou, Chengchao

2017-01-01

Sarsaparilla (Smilax Glabra Rhizome) exerts growth inhibitory effect on multiple cancer cells in vitro and in vivo, and redox-dependent persistent activation of ERK1/2 has been reported to underlie this effect. Here, we report an activation of ATM/ATR-dependent signaling pathway also as a mechanism for the cancer cell growth inhibition induced by the supernatant fraction of the water-soluble extract from sarsaparilla (SW). SW treatment (3.5 μg/μL) promoted the phosphorylations of ATM, ATR, and CHK1 in AGS and HT-29 cells. The ATM kinase inhibitor, KU55933, could reverse SW-induced ERK phosphorylation but not the reduced glutathione/oxidized glutathione (GSH/GSSG) imbalance in AGS cells. However, both the redox inhibitor glutathione (GSH) and ERK inhibitor U0126 antagonized SW-induced phosphorylations of ATM, ATR, and CHK1 in AGS cells. We further found KU55933 significantly antagonized SW-induced S phase arrest, apoptosis, autophagy and the resultant cell growth inhibition. Our results provide another molecular basis for the anticancer action of sarsaparilla.

Waves of Cdk1 Activity in S Phase Synchronize the Cell Cycle in Drosophila Embryos.

PubMed

Deneke, Victoria E; Melbinger, Anna; Vergassola, Massimo; Di Talia, Stefano

2016-08-22

Embryos of most metazoans undergo rapid and synchronous cell cycles following fertilization. While diffusion is too slow for synchronization of mitosis across large spatial scales, waves of Cdk1 activity represent a possible process of synchronization. However, the mechanisms regulating Cdk1 waves during embryonic development remain poorly understood. Using biosensors of Cdk1 and Chk1 activities, we dissect the regulation of Cdk1 waves in the Drosophila syncytial blastoderm. We show that Cdk1 waves are not controlled by the mitotic switch but by a double-negative feedback between Cdk1 and Chk1. Using mathematical modeling and surgical ligations, we demonstrate a fundamental distinction between S phase Cdk1 waves, which propagate as active trigger waves in an excitable medium, and mitotic Cdk1 waves, which propagate as passive phase waves. Our findings show that in Drosophila embryos, Cdk1 positive feedback serves primarily to ensure the rapid onset of mitosis, while wave propagation is regulated by S phase events. Copyright © 2016 Elsevier Inc. All rights reserved.

The Variability of Childhood Diarrhea in Karachi, Pakistan, 2002–2006

PubMed Central

Luby, Stephen P.; Agboatwalla, Mubina; Hoekstra, Robert M.

2011-01-01

Diarrhea burden is often estimated using cross-sectional surveys. We measured variability in diarrhea prevalence among children < 5 years of age living in squatter settlements in central Karachi, Pakistan. We pooled data from non-intervention control households from studies conducted from 2002 through 2006. The prevalence of diarrhea varied on average by 29% from one week to the next, by 37% from one month to the next, and during peak diarrhea season by 32% from one year to the next. During 24 months when the same nine neighborhoods were under surveillance, each month the prevalence of diarrhea varied by at least an order of magnitude from the lowest to the highest prevalence neighborhood, and each neighborhood recorded the highest diarrhea prevalence during at least one month. Cross-sectional surveys are unreliable measures of diarrhea prevalence. PMID:21633021

Tobacco control laws in Pakistan and their implementation: A pilot study in Karachi.

PubMed

Khan, Javaid Ahmed; Amir Humza Sohail, Abdul Malik; Arif Maan, Muhammad Arslan

2016-07-01

In order to limit the high prevalence of tobacco use in Pakistan various tobacco control laws have been implemented. The objective of this study is to serve as a pilot study to assess the implementation of these laws in the largest city of Pakistan, Karachi. A cross-sectional study was conducted in Karachi. The implementation of tobacco control laws in 'smoke-free' places, the adherence of tobacco companies to these laws, the regulation of cigarette sale, and the awareness and views of the general public regarding tobacco control laws were assessed via direct observation by visits and through self-administered questionnaires. The implementation of tobacco control laws in 'smoke-free' public places was found to be poor. Out of 37, only 23(62%) brands displayed pictorial warnings on their packs. 3(8%) of the brands were available in two different kinds of packs, both with and without pictorial warnings. Cigarette sale to minors was taking place at 80(85%) of the visited cigarette outlets. 50(53%) of the outlets displayed cigarette advertisements in the form of posters. 46(40%) of the persons questioned had awareness regarding the existence of ban on smoking in public places and 126(90%) of these were in favour of it. The implementation of tobacco control law in Pakistan is poor. Non adherence to the law in public places was alarmingly high. Also, the study demonstrates the poor compliance to the tobacco control laws by tobacco companies. The sale of cigarettes is almost unregulated.

Association of post-traumatic stress disorder and work performance: A survey from an emergency medical service, Karachi, Pakistan

PubMed Central

Kerai, Salima; Pasha, Omrana; Khan, Uzma; Islam, Muhammad; Asad, Nargis; Razzak, Junaid

2017-01-01

BACKGROUND: The purpose of the study was to explore the association between post-traumatic stress disorder (PTSD) and work performance of emergency medical services personnel in Karachi, Pakistan. METHODS: Emergency medical service personnel were screened for potential PTSD using Impact of Event Scale-Revised (IES-R). Work performance was assessed on the basis of five variables: number of late arrivals to work, number of days absent, number of days sick, adherence to protocol, and patient satisfaction over a period of 3 months. In order to model outcomes like the number of late arrivals to work, days absent and days late, negative binomial regression was applied, whereas logistic regression was applied for adherence to protocol and linear for patient satisfaction scores. RESULTS: Mean scores of PTSD were 24.0±12.2. No association was found between PTSD and work performance measures: number of late arrivals to work (RRadj 0.99; 0.98–1.00), days absent (RRadj 0.98; 0.96–0.99), days sick (RRadj 0.99; 0.98–1.00), adherence to protocol (ORadj 1.01; 0.99–1.04) and patient satisfaction (β 0.001%–0.03%) after adjusting for years of formal schooling, living status, coping mechanism, social support, working hours, years of experience and anxiety or depression. CONCLUSION: No statistically significant association was found between PTSD and work performance amongst EMS personnel in Karachi, Pakistan. PMID:28680519

Association of post-traumatic stress disorder and work performance: A survey from an emergency medical service, Karachi, Pakistan.

PubMed

Kerai, Salima; Pasha, Omrana; Khan, Uzma; Islam, Muhammad; Asad, Nargis; Razzak, Junaid

2017-01-01

The purpose of the study was to explore the association between post-traumatic stress disorder (PTSD) and work performance of emergency medical services personnel in Karachi, Pakistan. Emergency medical service personnel were screened for potential PTSD using Impact of Event Scale-Revised (IES-R). Work performance was assessed on the basis of five variables: number of late arrivals to work, number of days absent, number of days sick, adherence to protocol, and patient satisfaction over a period of 3 months. In order to model outcomes like the number of late arrivals to work, days absent and days late, negative binomial regression was applied, whereas logistic regression was applied for adherence to protocol and linear for patient satisfaction scores. Mean scores of PTSD were 24.0±12.2. No association was found between PTSD and work performance measures: number of late arrivals to work ( RR adj 0.99; 0.98-1.00), days absent ( RR adj 0.98; 0.96-0.99), days sick ( RR adj 0.99; 0.98-1.00), adherence to protocol ( OR adj 1.01; 0.99-1.04) and patient satisfaction ( β 0.001%-0.03%) after adjusting for years of formal schooling, living status, coping mechanism, social support, working hours, years of experience and anxiety or depression. No statistically significant association was found between PTSD and work performance amongst EMS personnel in Karachi, Pakistan.

Predictors and outcome of tetanus in newborns in slum areas of Karachi City: a case control study.

PubMed

Sohaila, Arjumand; Shafiq, Yasir; Azim, Shazia; Baloch, Benazir; Akhtar, Ali Syed Muhammad; Tikmani, Shiyam Sunder; Brown, Nick

2015-08-07

Tetanus in newborns, is an under-reported public health problem and a major cause of mortality in developing countries. This study aimed to determine the predictors and outcome of tetanus in newborn infants in the slums of Bin-Qasim town, Karachi, Pakistan. We conducted a case-control study at primary health care centers of slums of Bin-Qasim town, area located adjacent to Bin Qasim seaport in Karachi, from January 2003 to December 2013. Cases were infants aged ≤30 days with tetanus, as defined by the World Health Organization. Controls were newborn infants aged ≤30 days without Tetanus, who were referred for a checkup or minor illnesses. The case to control ratio was 1:2. We analyzed 26 cases and 52 controls. The case fatality was 70.8%. We identified four independent predictors of Tetanus in newborns: maternal education (only religious education with no formal education OR 51.95; 95% CI 3.69-731), maternal non-vaccination (OR 24.55; 95% CI 1.01-131.77), lack of a skilled birth attendant (OR 44.00; 95% CI 2.30-840.99), and delivery at home (OR 11.54; 95% CI 1.01-131.77). We identified several potentially modifiable socio-demographic risk factors for Tetanus in newborns, including maternal education and immunization status, birth site, and lack of a skilled birth attendant. Prioritization of these risk factors could be useful for planning preventive and cost-effective measures.

Physalis angulata induced G2/M phase arrest in human breast cancer cells.

PubMed

Hsieh, Wen-Tsong; Huang, Kuan-Yuh; Lin, Hui-Yi; Chung, Jing-Gung

2006-07-01

Physalis angulata (PA) is employed in herbal medicine around the world. It is used to treat diabetes, hepatitis, asthma and malaria in Taiwan. We have evaluated PA as a cancer chemopreventive agent in vitro by studying the role of PA in regulation of proliferation, cell cycle and apoptosis in human breast cancer cell lines. PA inhibited cell proliferation and induced G2/M arrest and apoptosis in human breast cancer MAD-MB 231 and MCF-7 cell lines. In this study, under treatment with various concentrations of PA in MDA-MB 231 cell line, we checked mRNA levels for cyclin A and cyclin B1 and the protein levels of cyclin A and cyclin B1, Cdc2 (cyclin-dependent kinases), p21(waf1/cip1) and P27(Kip1) (cyclin-dependent kinase inhibitors), Cdc25C, Chk2 and Wee1 kinase (cyclin-dependent kinase relative factors) in cell cycle G2/M phase. From those results, we determined that PA arrests MDA-MB 231 cells at the G2/M phase by (i) inhibiting synthesis or stability of mRNA and their downstream protein levels of cyclin A and cyclin B1, (ii) increasing p21(waf1/cip1) and P27(kip1) levels, (iii) increasing Chk2, thus causing an increase in Cdc25C phosphorylation/inactivation and inducing a decrease in Cdc2 levels and an increase in Wee1 level. According to the results obtained, PA appears to possess anticarcinogenic properties; these results suggest that the effect of PA on the levels of phosphorylated/inactivated Cdc25C are mediated by Chk2 activation, at least in part, via p21(waf1/cip1) and P27(kip1) cyclin-dependent kinase inhibitors pathway to arrest cells at G2/M phase in breast cancer carcinoma cells.

Design checkpoint kinase 2 inhibitors by pharmacophore modeling and virtual screening techniques.

PubMed

Wang, Yen-Ling; Lin, Chun-Yuan; Shih, Kuei-Chung; Huang, Jui-Wen; Tang, Chuan-Yi

2013-12-01

Damage to DNA is caused by ionizing radiation, genotoxic chemicals or collapsed replication forks. When DNA is damaged or cells fail to respond, a mutation that is associated with breast or ovarian cancer may occur. Mammalian cells control and stabilize the genome using a cell cycle checkpoint to prevent damage to DNA or to repair damaged DNA. Checkpoint kinase 2 (Chk2) is one of the important kinases, which strongly affects DNA-damage and plays an important role in the response to the breakage of DNA double-strands and related lesions. Therefore, this study concerns Chk2. Its purpose is to find potential inhibitors using the pharmacophore hypotheses (PhModels) and virtual screening techniques. PhModels can identify inhibitors with high biological activities and virtual screening techniques are used to screen the database of the National Cancer Institute (NCI) to retrieve compounds that exhibit all of the pharmacophoric features of potential inhibitors with high interaction energy. Ten PhModels were generated using the HypoGen best algorithm. The established PhModel, Hypo01, was evaluated by performing a cost function analysis of its correlation coefficient (r), root mean square deviation (RMSD), cost difference, and configuration cost, with the values 0.955, 1.28, 192.51, and 16.07, respectively. The result of Fischer's cross-validation test for the Hypo01 model yielded a 95% confidence level, and the correlation coefficient of the testing set (rtest) had a best value of 0.81. The potential inhibitors were then chosen from the NCI database by Hypo01 model screening and molecular docking using the cdocker docking program. Finally, the selected compounds exhibited the identified pharmacophoric features and had a high interaction energy between the ligand and the receptor. Eighty-three potential inhibitors for Chk2 are retrieved for further study. Copyright © 2013 Elsevier Ltd. All rights reserved.

Persistent activation of DNA damage signaling in response to complex mixtures of PAHs in air particulate matter

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jarvis, Ian W.H., E-mail: Ian.Jarvis@ki.se; Bergvall, Christoffer, E-mail: Christoffer.Bergvall@anchem.su.se; Bottai, Matteo, E-mail: Matteo.Bottai@ki.se

2013-02-01

Complex mixtures of polycyclic aromatic hydrocarbons (PAHs) are present in air particulate matter (PM) and have been associated with many adverse human health effects including cancer and respiratory disease. However, due to their complexity, the risk of exposure to mixtures is difficult to estimate. In the present study the effects of binary mixtures of benzo[a]pyrene (BP) and dibenzo[a,l]pyrene (DBP) and complex mixtures of PAHs in urban air PM extracts on DNA damage signaling was investigated. Applying a statistical model to the data we observed a more than additive response for binary mixtures of BP and DBP on activation of DNAmore » damage signaling. Persistent activation of checkpoint kinase 1 (Chk1) was observed at significantly lower BP equivalent concentrations in air PM extracts than BP alone. Activation of DNA damage signaling was also more persistent in air PM fractions containing PAHs with more than four aromatic rings suggesting larger PAHs contribute a greater risk to human health. Altogether our data suggests that human health risk assessment based on additivity such as toxicity equivalency factor scales may significantly underestimate the risk of exposure to complex mixtures of PAHs. The data confirms our previous findings with PAH-contaminated soil (Niziolek-Kierecka et al., 2012) and suggests a possible role for Chk1 Ser317 phosphorylation as a biological marker for future analyses of complex mixtures of PAHs. -- Highlights: ► Benzo[a]pyrene (BP), dibenzo[a,l]pyrene (DBP) and air PM PAH extracts were compared. ► Binary mixture of BP and DBP induced a more than additive DNA damage response. ► Air PM PAH extracts were more potent than toxicity equivalency factor estimates. ► Larger PAHs (> 4 rings) contribute more to the genotoxicity of PAHs in air PM. ► Chk1 is a sensitive marker for persistent activation of DNA damage signaling from PAH mixtures.« less

Vitamin D inhibits growth of human airway smooth muscle cells through growth factor-induced phosphorylation of retinoblastoma protein and checkpoint kinase 1

PubMed Central

Damera, G; Fogle, HW; Lim, P; Goncharova, EA; Zhao, H; Banerjee, A; Tliba, O; Krymskaya, VP; Panettieri, RA

2009-01-01

Background and purpose: Airway remodelling in asthma is manifested, in part, as increased airway smooth muscle (ASM) mass, reflecting myocyte proliferation. We hypothesized that calcitriol, a secosteroidal vitamin D receptor (VDR) modulator, would inhibit growth factor-induced myocyte proliferation. Experimental approach: Human ASM cell cultures were derived from bronchial samples taken during surgery. ASM cells were treated with platelet-derived growth factor (PDGF) (10 ng·mL−1) for 24 h in the presence of calcitriol, dexamethasone or a checkpoint kinase 1 (Chk1) inhibitor (SB218078). The effects of calcitriol on PDGF-mediated cell proliferation were assessed by thymidine incorporation assay, propidium iodide-based cell cycle analysis, caspase-3 assay and immunoblotting for specific cell cycle modulators. Key results: Calcitriol, but not dexamethasone, inhibited PDGF-induced ASM DNA synthesis concentration dependently (IC50= 520 ± 52 nM). These effects were associated with VDR-mediated expression of cytochrome CYP24A1 with no effects on ASM apoptosis. Calcitriol substantially inhibited (P < 0.01) PDGF-stimulated cell growth in ASM derived from both normal (59 ± 8%) and asthmatic subjects (57 ± 9%). Calcitriol inhibited PDGF-induced phosphorylation of retinoblastoma protein (Rb) and Chk1, with no effects on PDGF-mediated activation of extracellular signal-regulated kinases 1/2, PI3-kinase and S6 kinase, or expression of p21Waf/Cip-1, p27Kip1, cyclin D and E2F-1. Consistent with these observations, SB218078 also inhibited (IC50= 450 ± 100 pM) PDGF-induced cell cycle progression. Conclusions and implications: Calcitriol decreased PDGF-induced ASM cell growth by inhibiting Rb and Chk1 phosphorylation. This Research Paper is the subject of a Commentary in this issue by Clifford and Knox (pp. 1426–1428). To view this article visit http://www3.interscience.wiley.com/journal/121548564/issueyear?year=2009 PMID:19814732

DNA damage response in renal ischemia-reperfusion and ATP-depletion injury of renal tubular cells.

PubMed

Ma, Zhengwei; Wei, Qingqing; Dong, Guie; Huo, Yuqing; Dong, Zheng

2014-07-01

Renal ischemia-reperfusion leads to acute kidney injury (AKI) that is characterized pathologically by tubular damage and cell death, followed by tubular repair, atrophy and interstitial fibrosis. Recent work suggested the possible presence of DNA damage response (DDR) in AKI. However, the evidence is sketchy and the role and regulation of DDR in ischemic AKI remain elusive. In this study, we demonstrated the induction of phosphorylation of ATM, H2AX, Chk2 and p53 during renal ischemia-reperfusion in mice, suggesting DDR in kidney tissues. DDR was also induced in vitro during the recovery or "reperfusion" of renal proximal tubular cells (RPTCs) after ATP depletion. DDR in RPTCs was abrogated by supplying glucose to maintain ATP via glycolysis, indicating that the DDR depends on ATP depletion. The DDR was also suppressed by the general caspase inhibitor z-VAD and the overexpression of Bcl-2, supporting a role of apoptosis-associated DNA damage in the DDR. N-acetylcysteine (NAC), an antioxidant, suppressed the phosphorylation of ATM and p53 and, to a less extent, Chk2, but NAC increased the phosphorylation and nuclear foci formation of H2AX. Interestingly, NAC increased apoptosis, which may account for the observed H2AX activation. Ku55933, an ATM inhibitor, blocked ATM phosphorylation and ameliorated the phosphorylation of Chk2 and p53, but it increased H2AX phosphorylation and nuclear foci formation. Ku55933 also increased apoptosis in RPTCs following ATP depletion. The results suggest that DDR occurs during renal ischemia-reperfusion in vivo and ATP-depletion injury in vitro. The DDR is partially induced by apoptosis and oxidative stress-related DNA damage. ATM, as a sensor in the DDR, may play a cytoprotective role against tubular cell injury and death. Copyright © 2014 Elsevier B.V. All rights reserved.

Proteasome activity is important for replication recovery, CHK1 phosphorylation and prevention of G2 arrest after low-dose formaldehyde

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ortega-Atienza, Sara; Green, Samantha E.; Zhitkovich, Anatoly, E-mail: anatoly_zhitkovich@brown.edu

2015-07-15

Formaldehyde (FA) is a human carcinogen with numerous sources of environmental and occupational exposures. This reactive aldehyde is also produced endogenously during metabolism of drugs and other processes. DNA–protein crosslinks (DPCs) are considered to be the main genotoxic lesions for FA. Accumulating evidence suggests that DPC repair in high eukaryotes involves proteolysis of crosslinked proteins. Here, we examined a role of the main cellular proteolytic machinery proteasomes in toxic responses of human lung cells to low FA doses. We found that transient inhibition of proteasome activity increased cytotoxicity and diminished clonogenic viability of FA-treated cells. Proteasome inactivation exacerbated suppressive effectsmore » of FA on DNA replication and increased the levels of the genotoxic stress marker γ-H2AX in normal human cells. A transient loss of proteasome activity in FA-exposed cells also caused delayed perturbations of cell cycle, which included G2 arrest and a depletion of S-phase populations at FA doses that had no effects in control cells. Proteasome activity diminished p53-Ser15 phosphorylation but was important for FA-induced CHK1 phosphorylation, which is a biochemical marker of DPC proteolysis in replicating cells. Unlike FA, proteasome inhibition had no effect on cell survival and CHK1 phosphorylation by the non-DPC replication stressor hydroxyurea. Overall, we obtained evidence for the importance of proteasomes in protection of human cells against biologically relevant doses of FA. Biochemically, our findings indicate the involvement of proteasomes in proteolytic repair of DPC, which removes replication blockage by these highly bulky lesions. - Highlights: • Proteasome inhibition enhances cytotoxicity of low-dose FA in human lung cells. • Active proteasomes diminish replication-inhibiting effects of FA. • Proteasome activity prevents delayed G2 arrest in FA-treated cells. • Proteasome inhibition exacerbates replication stress by FA in normal human cells. • Protective role of proteasomes is linked to repair of DNA–protein crosslinks.« less

Assessment of knowledge, attitudes and practices towards newborn screening for congenital hypothyroidism before and after a health education intervention in pregnant women in a hospital setting in Pakistan.

PubMed

Tariq, Batha; Ahmed, Ayesha; Habib, Atif; Turab, Ali; Ali, Noshad; Soofi, Sajid Bashir; Nooruddin, Shanila; Kumar, Rekha J; Tariq, Amin; Shaheen, Fariha; Ariff, Shabina

2018-03-01

Most congenital hypothyroidism (CH) is not avertable; however, the adverse effects of CH are preventable with early detection and treatment. It is a common congenital endocrine disorder that affects 1 in 2000-4000 newborns globally. The true incidence in Pakistan is unknown. Data from hospital studies quote an incidence of 1 in 1600-2000. The aim of this study was to uncover existing knowledge of CH and screening for the condition and to assess the impact of health education on mothers' knowledge and attitudes towards having their newborns screened. The study was conducted from January 2012 to August 2013 at a local hospital in Karachi, Pakistan. This was a prospective, interventional cohort study implemented through a pre- and post-cross-sectional knowledge, attitudes and practices (KAP) survey. Interviews were conducted using structured questionnaires on CH. At baseline (pre-intervention survey), 400 participants consented and 355 (88.9%) completed the study. There was a significant increase in awareness among participating women following the intervention (20% to approximately 98%). Similarly, 78.9% agreed to opt for a screening test for their newborns following delivery as compared with 57.7% in the pre-intervention KAP survey (relative risk 1.38, p-value <0.0001). Unfortunately, the majority of mothers were unaware of CH and its implications, leading to less screening and fewer diagnoses. This study underlines the importance of education in screening programmes to create awareness and maximize uptake.

Nurses' knowledge of evidence-based guidelines for prevention of ventilator-associated pneumonia in critical care areas: a pre and post test design.

PubMed

Meherali, Salima Moez; Parpio, Yasmin; Ali, Tazeen S; Javed, Fawad

2011-01-01

Ventilator associated pneumonia (VAP) is a common hospital acquired pneumonia in ventilated patients. VAP is associated with increased morbidity, mortality duration of hospitalization and cost of treatment. Critical care nurses are usually unaware of evidence based preventive guidelines for VAP, resulting in negative impact on all aspects of patient care. This study investigated the impact of a 5-hour teaching module on nurses' knowledge to practice evidence based guidelines for the prevention of VAP. This study was conducted at a private tertiary care teaching hospital in Karachi, Pakistan. Single group pre-test design was used. Forty nurses were included in the study. The knowledge of nurses was assessed before, immediately after and 4 weeks after the intervention. The final sample (n=40) was selected on the basis of the set inclusion criteria. The demographic data sheet was used to collect relevant information about the participants. Knowledge was assessed through a self-developed validated tool, consisting of multiple choice questions. The difference in knowledge was analysed through repeated measures of analysis of variance. The mean scores at 3 time points were compared using the Tukey's multiple comparison procedure. Knowledge scores of participants increased significantly after the educational intervention in the first post-test; however, there was a decline in the score in post-test 2. the 5-hour teaching module significantly enhanced nurses' knowledge towards evidence based guidelines for the prevention of VAP. Further research is needed to assess the impact of training on nursing practice and to explore factors affecting attitudinal change.

Feto-maternal outcomes and Glycemic control in Metformin versus insulin treated Gestational Diabetics

PubMed Central

Arshad, Rabia; Khanam, Samia; Shaikh, Fuad; Karim, Nasim

2017-01-01

Objective: To evaluate and compare feto-maternal outcomes and glycemic control in metformin versus insulin treated gestational diabetics. Methods: The study was conducted in 2010- 2012 as a part of M. Phil at Civil hospital, Lyari General Hospital and Mamji Hospital in Karachi. After written informed consent, 71 GDM diagnosed females with WHO criteria were enrolled. They were divided into two groups. Group-A, 32 females were given oral metformin 500 mg TDS while Group-B, 39 females were given insulin 0.8-0.9 mg/kg/day in two divided doses subcutaneously. Patients were followed till term. Feto-maternal outcomes were evaluated in 25 patients in each group who completed the study. Results: When groups were compared, newborns in Group-B were significantly more in weight (p=0.01). Significant numbers of babies were delivered after 38 weeks of pregnancy in Group-B (P=0.021). There were two intrauterine deaths and significantly higher HbA1C at term in Group-B. (P=0.03). FBS at term was non-significant (p=0.079) and there was more number of cesarean sections due to feto-maternal disproportion in Group-B (28% vs.2%). Results analyzed for glycemic control before and after the treatment revealed that FBS was statistically less in Group-A (p=0.00) whereas for Group-B the value of FBS and HbA1C was statistically high. (p=0.002 & 0.04 respectively). Conclusion: Metformin has produced better effects on feto-maternal outcomes and glycemic control in comparison to Insulin in GDM. PMID:29142561

Feto-maternal outcomes and Glycemic control in Metformin versus insulin treated Gestational Diabetics.

PubMed

Arshad, Rabia; Khanam, Samia; Shaikh, Fuad; Karim, Nasim

2017-01-01

To evaluate and compare feto-maternal outcomes and glycemic control in metformin versus insulin treated gestational diabetics. The study was conducted in 2010- 2012 as a part of M. Phil at Civil hospital, Lyari General Hospital and Mamji Hospital in Karachi. After written informed consent, 71 GDM diagnosed females with WHO criteria were enrolled. They were divided into two groups. Group-A, 32 females were given oral metformin 500 mg TDS while Group-B, 39 females were given insulin 0.8-0.9 mg/kg/day in two divided doses subcutaneously. Patients were followed till term. Feto-maternal outcomes were evaluated in 25 patients in each group who completed the study. When groups were compared, newborns in Group-B were significantly more in weight (p=0.01). Significant numbers of babies were delivered after 38 weeks of pregnancy in Group-B (P=0.021). There were two intrauterine deaths and significantly higher HbA 1 C at term in Group-B. (P=0.03). FBS at term was non-significant (p=0.079) and there was more number of cesarean sections due to feto-maternal disproportion in Group-B (28% vs.2%). Results analyzed for glycemic control before and after the treatment revealed that FBS was statistically less in Group-A (p=0.00) whereas for Group-B the value of FBS and HbA 1 C was statistically high. (p=0.002 & 0.04 respectively). Metformin has produced better effects on feto-maternal outcomes and glycemic control in comparison to Insulin in GDM.

A Voice Onset Time Analysis of Apical Stop Production in 3-Year-Olds

ERIC Educational Resources Information Center

Gilbert, John H. V.

1977-01-01

This paper reports data for voice onset time (VOT) for /d/ and /t/, from six children at average age 3;0. Values for /d/ clearly achieve the short voicing lag category of adults, reported previously. Values for /t/, however, are much more varied, although falling within the category long voicing lag. (CHK)

El idioma espanol en el mundo (The Spanish Language in the World)

ERIC Educational Resources Information Center

Baron Castro, Rodolfo

1975-01-01

This report to the Office of Ibero-American Education concerns the status of Spanish in five areas: 1) A program on Spanish in the Philippines; 2) Spanish in the United States; 3) Cooperation with the Commission on Spanish of UNESCO; 4) A professorship in Bogota, and 5) Spanish scientific terminology. (Text is in Spanish.) (CHK)

English-French Bilingual Education in the Early Grades: The Elgin Study through Grade Four

ERIC Educational Resources Information Center

Barik, Henri C.; Swain, Merrill

1976-01-01

This paper presents the results of an evaluation of a bilingual education program for English-speaking pupils, grades 1-4, in Ontario. It is a partial French immersion program, with instruction in French or English half of each day. Evaluative tests are described, and English and French language skills examined. (CHK)

A Decade of Progress: Lessons Learned in Developing the UCO Downtown

ERIC Educational Resources Information Center

Barthell, John F.; Simmons, Charlotte K.; Youngblood, Karen

2018-01-01

For over a decade, the University of Central Oklahoma (UCO) has been engaged in defining its role within the Oklahoma City (OKC) Metropolitan Area. By 2013, an enhanced physical presence developed for UCO within OKC itself, including the creation of the Academy of Contemporary Music and the CHK|Central Boathouse. Afterwards, and in accordance with…

Who is "Daddy" Revisited: The Status of Two-Year-Olds' Over-Extended Words in Use and Comprehension

ERIC Educational Resources Information Center

Thomson, Jean R.; Chapman, Robin S.

1977-01-01

Diary observations of two-year-olds' over-extended word use have been interpreted as arising from the word's underlying semantic feature structure. This interpretation was rejected after a study of five children. The need to construct models of early word meaning reflecting certain early language development patterns is discussed. (CHK)

Drinking water: a major source of lead exposure in Karachi, Pakistan.

PubMed

Ul-Haq, N; Arain, M A; Badar, N; Rasheed, M; Haque, Z

2011-11-01

Excess lead in drinking water is a neglected source of lead toxicity in Pakistan. A cross-sectional survey in 2007/08 was made of water samples from drinking water sources in Karachi, a large industrial city. This study aimed to compare lead levels between untreated ground water and treated surface (tap) water in 18 different districts. Of 216 ground and surface water samples collected, 86% had lead levels higher than the World Health Organization maximum acceptable concentration of l0 ppb. Mean lead concentration in ground water [146 (SD 119) ppb] was significantly higher than in surface water [77.1 (SD 54) ppb]. None of the 18 districts had a mean lead level of ground or surface water below the WHO cut-off and ground water sources in 9 districts had a severe level of contamination (>150 ppb). Urgent action is needed to eliminate sources of contamination.

Intellectual wellness in medical university teachers: Gender based comparison.

PubMed

Syed, Sadiqa; Rehman, Rehana; Hussain, Mehwish; Shaikh, Saifullah

2017-05-01

A cross section, questionnaire based study was carried out from January 2012 till December 2014 to compare intellectual wellness (IW) awareness on the basis of gender in teachers of basic sciences at medical universities of Karachi, Pakistan. Data was collected from 3 public and 5 private medical universities of Karachi, Pakistan. Questionnaire was tailored from "Wellness Wheel" and responses were aggregated for eight questions in the dimension of IW to obtain aggregate IW score. Reliability of the questionnaire was measured using Cronbach's alpha. The average intellectual score was 24.99 ± 3.93 with a minimum score of 8 and maximum 32.The frequency of keeping informed about research updates was significantly higher in males (p = 0.043) that emphasized significantly better IW awareness of male medical teachers involved in teaching of medical sciences in both public and private medical universities of Pakistan.

Risk assessment of dissolved trace metals in drinking water of Karachi, Pakistan.

PubMed

Karim, Zahida

2011-06-01

Health risk caused by the exposure to trace metals in water through different exposure pathways was investigated. Graphite furnace atomic absorption spectrometry was used for the determination of trace metals (nickel, copper, chromium, lead, cobalt, manganese and iron) in drinking water samples. The concentration of metals was compared with the world health organization (WHO) drinking water quality guideline values. Risk of metals on human health was evaluated using Hazard Quotient (HQ). Hazard quotients of all metals through oral ingestion and dermal absorption are found in the range of 1.11 × 10⁻² to 1.35 × 10⁻¹ and 8.52 × 10⁻⁵ to 9.75 × 10⁻², respectively. The results of the present study reflect the unlikely potential for adverse health effects to the inhabitants of Karachi due to the oral ingestion and dermal absorption of water containing these metals.

Content Validity of a Tool Measuring Medication Errors.

PubMed

Tabassum, Nishat; Allana, Saleema; Saeed, Tanveer; Dias, Jacqueline Maria

2015-08-01

The objective of this study was to determine content and face validity of a tool measuring medication errors among nursing students in baccalaureate nursing education. Data was collected from the Aga Khan University School of Nursing and Midwifery (AKUSoNaM), Karachi, from March to August 2014. The tool was developed utilizing literature and the expertise of the team members, expert in different areas. The developed tool was then sent to five experts from all over Karachi for ensuring the content validity of the tool, which was measured on relevance and clarity of the questions. The Scale Content Validity Index (S-CVI) for clarity and relevance of the questions was found to be 0.94 and 0.98, respectively. The tool measuring medication errors has an excellent content validity. This tool should be used for future studies on medication errors, with different study populations such as medical students, doctors, and nurses.

The common causes leading to pancytopenia in patients presenting to tertiary care hospital

PubMed Central

Das Makheja, Kirpal; Kumar Maheshwari, Bharat; Arain, Shafique; Kumar, Suneel; Kumari, Sangeeta; Vikash

2013-01-01

Objective: The objective of this study was to determine the frequency of common causes leading to Pancytopenia in patients presenting to tertiary care hospital at Karachi. Methods: A total of 62 patients with the diagnosis of Pancytopenia of more than one week duration were enrolled in the study. All patients underwent a detailed medical history and full physical examination followed by blood sampling for the investigations i.e. complete blood count with peripheral film, erythrocyte sedimentation rate (ESR), Malarial parasites (MP), liver function test, Renal function tests, PT and viral profile (HBsAg, Anti-HCV), Ultrasonography of abdomen. All patients underwent bone marrow aspiration and trephine biopsy for reporting and interpretation. Duration of study was six months, from May 2010 to November 2010. Results: The average age of the patients was 37.76 ± 16.38years. Out of 62 patients, 36 (58%) were male and 26 (42%) were female. Megaloblastic anemia was the commonest cause that was observed in 41.9% cases followed by acute myeloid leukemia 27.4%, aplastic anemia 19.4% and erythroid hyperplasia 11.3%. Conclusion : This study concluded that most common cause of pancytopenia is Megaloblastic anemia, followed by acute myeloid leukemia and aplastic anemia. Bone marrow examination is a single useful investigation which reveals the underlying cause in patients with pancytopenia. PMID:24353701

Tetralogy of Fallot with absent pulmonary valve syndrome; appropriate surgical strategies.

PubMed

Shahid, Fatima; Siddiqui, Maria Tariq; Amanullah, Muhammad Muneer

2015-05-01

To evaluate patients presenting with Tetralogy of Fallot with absent pulmonary valve syndrome to a tertiary care hospital and their surgical management. The retrospective study was conducted at Congenital Cardiac Services, Aga Khan University Hospital, Karachi, Pakistan, and comprised data of Tetralogy of Fallot patients between April 2007 and June 2012. Data was analysed together with follow-up echocardiography. Variables assessed included demographics, imaging, operative technique, complications, post-operative recovery and follow-up echocardiography. SPSS 17 was used for statistical analysis. Of the 204 patients, 6 (3%) had undergone surgical correction for Tetralogy of Fallot with absent pulmonary valve syndrome. All 6(100%) patients underwent complete repair. Median age for surgery was 8.5 years (range: 0.5-29 years). Of the different surgical strategies used, Contegra and Bioprosthetic valve placement had satisfactory outcome with minimal gradient at Right Ventricular Outflow Tract, good ventricular function and mild valvular regurgitation. One (16.6%) patient with Trans Annular Patch developed post-operative Right Ventricle Outflow Tract gradient of 80mmHg with moderate pulmonary regurgitation. One (16.6%) patient with monocusp valve developed free pulmonary regurgitation at 6 months. The other 4(66.6%) patients are currently free from any complications or re-intervention. Early surgery is preferred in symptomatic patients. The repair depends upon achieving integrity of pulmonary circulation which is best achieved by using right ventricle to pulmonary artery conduit or inserting a pulmonary valve.

Aspiration of breast abscess through wide bore 14-gauge intravenous cannula.

PubMed

Afridi, Shahida Parveen; Alam, Shams Nadeem; Ainuddin, Saman

2014-10-01

To aspirate breast abscess through a wide bore (14-gauge) intravenous (I/V) cannula and determine its efficacy in terms of the number of recurrences and number of aspirations. Case series. Dow University of Health Sciences and Civil Hospital and Bantva Hospital, Karachi, Pakistan, from January 2009 to December 2011. Patients with breast abscesses confirmed on ultrasound without skin ulceration were selected. The soft area of breast abscess with positive fluctuation was marked and fixed with index finger and thumb. A 14-gauge cannula was inserted. Pus was aspirated through a 50 cc syringe, repeated till no aspirate could be obtained. All patients were followed weekly for 4 weeks, clinically for size of lump, local tenderness and temperature, while complete resolution was confirmed on ultrasound, as resolution of the lesion. A total of 55 patients were included in this study. Mean age was 29 ± 5.58 years while ranging from 20 - 40 years. Complete resolution of abscess was seen in 31 (56.4%) cases by single aspiration. Second aspiration was required in 24 (43.6%) patients and third aspiration in single setting was required in one case only. Recurrence after the second aspiration occurred in 08 (14.5%). Incision drainage was required in 7 (12.7%) patients. Percutaneous aspiration of breast abscess through a wide bore (14-gauge) I/V cannula is a simple alternative to incision and drainage.

Crimean-Congo hemorrhagic fever nosocomial infection in a immunosuppressed patient, Pakistan: case report and virological investigation.

PubMed

Hasan, Zahra; Mahmood, Faisal; Jamil, Bushra; Atkinson, Barry; Mohammed, Murtaza; Samreen, Azra; Altaf, Lamia; Moatter, Tariq; Hewson, Roger

2013-03-01

Crimean-Congo hemorrhagic fever (CCHF) is endemic in the Baluchistan province, Pakistan. Sporadic outbreaks of CCHF occur throughout the year especially in individuals in contact with infected livestock. Nosocomial transmission remains a risk due to difficulties in the diagnosis of CCHF and limited availability of facilities for the isolation of suspected patients. Rapid diagnosis of CCHF virus infection is required for early management of the disease and to prevent transmission. This study describes the case of a 43-year-old surgeon who contracted CCHF during a surgical procedure in Quetta, Baluchistan and who was transferred to a tertiary care facility at the Aga Khan University Hospital, Karachi within 1 week of contracting the infection. Diagnosis of CCHF was made using a rapid real-time reverse transcription polymerase chain reaction (RT-PCR) assay for CCHF viral RNA. The patient had chronic hepatitis B and hepatitis D infection for which he had previously received a liver transplant. He proceeded to develop classic hemorrhagic manifestations and succumbed to the infection 14 days post-onset of disease. There was no further nosocomial transmission of the CCHF during the hospital treatment of the surgeon. Early diagnosis of CCHF enables rapid engagement of appropriate isolation, barrier nursing and infection control measures thus preventing nosocomial transmission of the virus. Copyright © 2012 Wiley Periodicals, Inc.

Professionalism in medical students at a private medical college in Karachi, Pakistan.

PubMed

Sobani, Zain-ul-abedeen; Mohyuddin, Muhammad Masaud; Farooq, Fahd; Qaiser, Kanza Noor; Gani, Faiz; Bham, Nida Shahab; Raheem, Ahmed; Mehraj, Vikram; Saeed, Syed Abdul; Sharif, Hasanat; Sheerani, Mughis; Zuberi, Rukhsana Wamiq; Beg, Mohamamd Asim

2013-07-01

To determine levels of professionalism in undergraduate medical students at a private medical college and assess how changes emerge during their training. The study was conducted at Aga Khan University, a tertiary care teaching hospital, during November and December 2011. Freshmen, Year 3 and Year 5 students were requested to fill out a questionnaire. It was designed to assess the participants' levels of professionalism and how they perceived the professional environment around them by incorporating previously described scales. The questionnaire was re-validated on a random sample of practising clinicians at the same hospital. SPSS 17 was used for statistical analysis. The study sample comprised 204 participants. The mean score for level of individual professionalism was 7.72+/-3.43. Only 13 (6.4%) students had a score one standard deviation above the faculty mean. About 24 (11.8%) were one standard deviation and 35 (17.2%) were 2 standard deviations below the faculty mean. The remaining 130 (63.7%) were >2 standard deviations below the faculty mean. Considering the level of education, the mean score for level of professionalism was 8.00+/-3.39 for freshmen, 6.85+/-3.41 for year 3 students, and 8.40+/-3.34 for year 5 students. The currently employed teaching practices inculcating the values of professionalism in medical students are serving as a buffer to maintain the pre-training levels of professionalism from declining.

Self-medication amongst university students of Karachi: prevalence, knowledge and attitudes.

PubMed

Zafar, Syed Nabeel; Syed, Reema; Waqar, Sana; Zubairi, Akbar Jaleel; Vaqar, Talha; Shaikh, Mehrine; Yousaf, Wajeeha; Shahid, Saman; Saleem, Sarah

2008-04-01

To determine the prevalence, attitude and knowledge of self-medication amongst university students of Karachi, Pakistan. This cross-sectional, study was conducted from Jan-Feb 2007. A convenience sample was taken from 2 medical and 2 non-medical universities of the city of Karachi, Pakistan. Data was analyzed using SPSS v 14 and associations were tested using the Chi square test. Of the 572 participants (mean age=21 +/- 1.8 years, Male: Female ratio=1:1.5), 295 were medical and 277 were non-medical students. The prevalence of self-medication was 76%. Forty three percent students stated that they alter the regimen of prescribed medicines while 61.9% stated that they stop taking a prescribed medicine without consulting a doctor. The most common reason for self-medication was previous experience (50.1%) and the most common symptoms were headache (72.4%), flu (65.5%), and fever (55.2%). Commonly used medicines were analgesics (88.3%), antipyretics (65.1%) and antibiotics (35.2%). Eighty seven percent of students thought self-medication could be harmful and 82.5% students thought that it was necessary to consult a doctor before taking a new medicine. There was no significant difference between the self medication practices of medical and non medical students (p=0.8) Prevalence of self-medication is high in the educated youth, despite majority being aware of its harmful effects. There is a need to educate the youth to ensure safe practices. Strict policies need to be implemented on the advertising and selling of medications to prevent this problem from escalating.

Sociodemographic Pattern of Depression in Urban Settlement of Karachi, Pakistan.

PubMed

Altaf, Areeba; Khan, Maham; Shah, Syed Raza; Fatima, Kaneez; Tunio, Sameer Altaf; Hussain, Mehwish; Khan, Muhammad Asim; Shaikh, Moazzam Ali; Arshad, Mohammad Hussham

2015-06-01

Depression is a global issue prevalent among developing countries like Pakistan as compared to developed countries. We conducted a study to assess the prevalence and identify the significant predictors of depression in an elite urban settlement in Karachi, Pakistan. This cross-sectional study was done in the elitist residential area of Karachi; Defence Housing Authority (DHA). Four hundred and twenty three participants were included by going to their residences. Self-administered questionnaires were handed out after taking informed consent. Level of depression was assessed by Patient Health Questionnaire (PHQ-9). Data were entered and analysed in Predictive Analytical Software v. 18.0. The mean and median total score of the scale were 5.9 ± 5.4 and 4 (7) respectively with minimum score 0 and maximum 27. In this sequence, 139 (32.86%) respondents were identified to be depressed. It was found that females were slight more depressed than males (p = 0.063). Regression Model identified only gender and marital status as significant predictors of depression. Having a female gender increased 0.658 times chance of being depressed (p = 0.047). Unmarried person had 0.296 times more likely to be depressed (p = 0.019). Boredom was considered as significant factor of depression by the participants (p< 0.0001). Odds ratio signified depression occurred 0.310 times more if one was bored. Depression should be considered as a major public health issue for the city. Public awareness should be done in all parts of the city in an attempt to reduce depression especially among the female gender.

Knowledge and attitude regarding euthanasia among medical students in the public and private medical schools of Karachi.

PubMed

Hassan, Wafa; Ahmad, Farah; Malik, Aisha; Ali, Saba

2013-02-01

To assess the awareness about and perception of euthanasia among medical students of Karachi. The cross-sectional study was conducted from December 2011 to March 2012 among students of private-sector and one public-sector medical college in Karachi. Data was analysed using SPSS version 17, and associations were worked out using chi-square test. Out of the 493 students, 226 (46%) were from the matriculation system and 194 (39%) from the Cambridge system, while the remaining 15% were from the American High School. The male-female ratio was 1:3. There were 284 (58%) students from the private medical college. Majority of the private medical school students (n = 284; 99.6%) knew about euthanasia, compared to the public-sector facility where only 161 (77%) knew of it. Of the total, 405 (82%) students agreed that it is physician-assisted suicide; 255 (52%) agreed to the idea of palliative care, claiming it was sufficient to maintain life; 226 (54%) disagreed that a doctor should not be allowed to administer a lethal dose while only 162 (33%) agreed to the idea of it; 285 (58%) disagreed that a law regarding the practice of euthanasia should not be introduced, whereas 134 (27%) agreed to it; 70 (14%) agreed to the practice of euthanasia, while 311 (63%) disagreed, mostly for religious reasons. The awareness of euthanasia was high, but a very small proportion of students approved of it. There is need to include palliative care and euthanasia in the Behavioural Science module in the under-graduation programme of both public and private medical schools.

Epidemiology, clinical presentation, and patterns of drug resistance of Salmonella Typhi in Karachi, Pakistan.

PubMed

Khan, M Imran; Soofi, Sajid Bashir; Ochiai, R Leon; Khan, Mohammad Jawed; Sahito, Shah Muhammad; Habib, Mohammad Atif; Puri, Mahesh K; Von Seidlein, Lorenz; Park, Jin Kyung; You, Young Ae; Ali, Mohammad; Nizami, S Qamarudding; Acosta, Camilo J; Sack, R Bradley; Clemens, John D; Bhutta, Zulfiqar A

2012-10-19

Enteric fever remains a major public health problem in Asia. Planning appropriate preventive measures such as immunization requires a clear understanding of disease burden. We conducted a community-based surveillance for Salmonella Typhi infection in children in Karachi, Pakistan. A de jure household census was conducted at baseline in the study setting to enumerate all individuals. A health-care facility-based passive surveillance system was used to capture episodes of fever lasting three or more 3 days in children 2 to 16 years old. A total of 7,401 blood samples were collected for microbiological confirmation, out of which 189 S. Typhi and 32 S. Paratyphi A isolates were identified with estimated annual incidences of 451/100,000 (95% CI: 446 - 457) and 76/100,000 (95% CI: 74 - 78) respectively. At the time of presentation, after adjusting for age, there was an association between the duration of fever and temperature at presentation, and being infected with multidrug-resistant S. Typhi. Of 189 isolates 83 were found to be resistant to first-line antimicrobial therapy. There was no statistically significant difference in clinical presentation of blood culture sensitive and resistant S. Typhi isolates. Incidence of S. Typhi in children is high in urban squatter settlements of Karachi, Pakistan. Findings from this study identified duration of fever and temperature at the time of presentation as important symptoms associated with blood culture-confirmed typhoid fever. Preventive strategies such as immunization and improvements in water and sanitation conditions should be the focus of typhoid control in urban settlements of Pakistan.

Morphotaxonomy and seasonal distribution of planktonic and benthic Prorocentrales in Karachi waters, Pakistan Northern Arabian Sea

NASA Astrophysics Data System (ADS)

Munir, Sonia; Burhan, Zaib-un-nisa; Naz, Tahira; Siddiqui, P. J. A.; Morton, Steve L.

2013-03-01

Morphotaxonomy and seasonal abundance of dinoflagellates of the genera Prorocentrum and Mesoporos (Prorocentrales) were studied from nutrient-rich waters, Karachi Harbor and the mouth of the Manora Channel, Pakistan during May 2002-July 2003. Using both light and scanning electron microscopy, 13 species of Prorocentrales were identified according to cell shape, size, ornamentation of thecal plates, and architecture of apical platelets, apical pore area, marginal pores, and intercalary bands. P. sigmoides, P. arcuatum, P. scutellum, P. donghaiense, P. balticum, P. minimum, P. emarginatum, P. lima, P. faustiae, and Mesoporos perforatus constitute new records for sindh coast of Pakistan. The most abundant species were P. minimum/P. balticum (4.5×103 cells/L), P. micans (1.1×103 cells/L), P. gracile / P. sigmoides (2.5×10 2 cells/L) and P. donghaiense (6.6×103 cells/L) at temperatures of 29-31°C and salinities of 35-40. Maximum abundance was observed in winter and lower abundance in summer. There was no significant change in the distribution of species between stations except for the benthic species which occurred close to Karachi Harbor waters. Significant positive correlations were observed between Prorocentrum spp. and temperature ( R 2 =0.27) and negative correlations with salinity ( R 2 =-0.32) except for P. minimum and P. emarginatum which has negative correlation with temperature ( R 2 =-0.24) and positive with salinity ( R 2 =0.08, 0.19). The finding of potential okadaic-acid producing species of benthic Prorocentrum call for monitoring for possible human health problems in this region.

Objects of temporary contraception: an exploratory study of women's perspectives in Karachi, Pakistan

PubMed Central

Marvi, Kamyla; Howard, Natasha

2013-01-01

Objectives To explore perspectives of three modern contraceptive objects, using an emic approach, among women in a low-income community in Karachi, Pakistan. Design A qualitative interview study design was employed, using qualitative content analysis with an inductive approach and manual thematic coding. Setting Shah Faisal Colony, Karachi. Participants 20 women, potential contraceptive users of reproductive age and living within a health centre catchment, were purposively selected to provide a similar number of non-users (n=5), contraceptive injection users (n=7), pill users (n=4), and intrauterine device users (n=4). One interview was excluded because it was not recorded. No other exclusion criteria were used. Primary and secondary outcome measures The primary outcome was interpretation of potency and effects of selected family planning objects. Secondary outcome measures were knowledge of family planning and description of therapeutic approaches used and preferred. Results Awareness of family planning was high. Women described different therapeutic approaches, stating they generally preferred modern medicine for contraception as it was fastest and most powerful. They reported that fear of some contraceptive objects, particularly injections and intrauterine contraceptive devices, influenced their choices. Women explained their perceptions of how the heating effects of contraceptives could cause unwanted side effects including menstrual irregularities, weight gain and weakness, leading to disease. Conclusions Most women wanted family planning, but remained dissatisfied with the available contraceptives and their effects. While women reported that they relied on modern medicine for contraception, their descriptions of how contraceptives affected their health relied on the hot–cold explanatory idiom of traditional medicine. PMID:23906959

Blood and hair lead in children with different extents of iron deficiency in Karachi

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ataur Rahman, Muhammad; Rahman, Bushra; Saeed Ahmad, Muhammad

Childhood iron deficiency has a high incidence in Pakistan. Some but not all studies have shown that dietary iron deficiency may cause increased absorption of lead as both compete for the same transporters in the small intestine. Therefore, children in Pakistan, residing in heavily polluted cities like Karachi may be prone to lead poisoning. This hypothesis was tested by investigating blood and hair lead concentrations in children from Karachi who were divided into four groups of iron status; normal, borderline iron deficiency, iron deficiency and iron deficiency anaemia. A prospective observational study was conducted where 269 children were categorized intomore » four groups of iron status using the World Health Organization criteria and one based on soluble transferrin receptor measurements. Blood iron status was determined using a full blood count, serum iron, ferritin, transferrin saturation and soluble transferrin receptor measurements. Blood lead was determined by graphite atomic absorption spectroscopy, whereas hair lead was assessed using an inductively coupled plasma atomic emission spectroscopy technique. Blood lead concentrations were significantly higher in children with iron deficiency anaemia (mean [95% confidence intervals] were 24.9 [22.6-27.2] {mu}g/dL) compared to those with normal iron status (19.1 [16.8-21.4] {mu}g/dL) using WHO criteria. In contrast, hair lead content was not significantly different in children of different iron status. Our findings reinforce the importance of not only reducing environmental lead pollution but also the development of national health strategies to reduce childhood iron deficiency in Pakistan.« less

Los problemas de contenido y de empleo del verbo haber (Problems of Meaning and Use of the Verb "Haber.")

ERIC Educational Resources Information Center

Perez Botero, Luis A.

1975-01-01

Discusses the derivation, meaning and both past and present uses of the Spanish verb "haber." The verb refers to relationships of possession, duration and existence, and is used as an auxiliary. Extant derivative forms of the verb in other languages and earlier Spanish meanings are noted. (Text is in Spanish.) (CHK)

Deficiency in DNA damage response of enterocytes accelerates intestinal stem cell aging in Drosophila.

PubMed

Park, Joung-Sun; Jeon, Ho-Jun; Pyo, Jung-Hoon; Kim, Young-Shin; Yoo, Mi-Ae

2018-03-07

Stem cell dysfunction is closely linked to tissue and organismal aging and age-related diseases, and heavily influenced by the niche cells' environment. The DNA damage response (DDR) is a key pathway for tissue degeneration and organismal aging; however, the precise protective role of DDR in stem cell/niche aging is unclear. The Drosophila midgut is an excellent model to study the biology of stem cell/niche aging because of its easy genetic manipulation and its short lifespan. Here, we showed that deficiency of DDR in Drosophila enterocytes (ECs) accelerates intestinal stem cell (ISC) aging. We generated flies with knockdown of Mre11 , Rad50 , Nbs1 , ATM , ATR , Chk1 , and Chk2 , which decrease the DDR system in ECs. EC-specific DDR depletion induced EC death, accelerated the aging of ISCs, as evidenced by ISC hyperproliferation, DNA damage accumulation, and increased centrosome amplification, and affected the adult fly's survival. Our data indicated a distinct effect of DDR depletion in stem or niche cells on tissue-resident stem cell proliferation. Our findings provide evidence of the essential role of DDR in protecting EC against ISC aging, thus providing a better understanding of the molecular mechanisms of stem cell/niche aging.

A high content, high throughput cellular thermal stability assay for measuring drug-target engagement in living cells.

PubMed

Massey, Andrew J

2018-01-01

Determining and understanding drug target engagement is critical for drug discovery. This can be challenging within living cells as selective readouts are often unavailable. Here we describe a novel method for measuring target engagement in living cells based on the principle of altered protein thermal stabilization / destabilization in response to ligand binding. This assay (HCIF-CETSA) utilizes high content, high throughput single cell immunofluorescent detection to determine target protein levels following heating of adherent cells in a 96 well plate format. We have used target engagement of Chk1 by potent small molecule inhibitors to validate the assay. Target engagement measured by this method was subsequently compared to target engagement measured by two alternative methods (autophosphorylation and CETSA). The HCIF-CETSA method appeared robust and a good correlation in target engagement measured by this method and CETSA for the selective Chk1 inhibitor V158411 was observed. However, these EC50 values were 23- and 12-fold greater than the autophosphorylation IC50. The described method is therefore a valuable advance in the CETSA method allowing the high throughput determination of target engagement in adherent cells.

DNA-PK, ATM and ATR collaboratively regulate p53-RPA interaction to facilitate homologous recombination DNA repair

PubMed Central

Serrano, Moises A.; Li, Zhengke; Dangeti, Mohan; Musich, Phillip R.; Patrick, Steve; Roginskaya, Marina; Cartwright, Brian; Zou, Yue

2012-01-01

Homologous recombination (HR) and nonhomologous end-joining (NHEJ) are two distinct DNA double-strand break (DSB) repair pathways. Here we report that DNA-dependent protein kinase (DNA-PK), the core component of NHEJ, partnering with DNA-damage checkpoint kinases ataxia telangiectasia mutated (ATM) and ATM- and Rad3-related (ATR), regulates HR repair of DSBs. The regulation was accomplished through modulation of the p53 and replication protein A (RPA) interaction. We show that upon DNA damage, p53 and RPA were freed from a p53-RPA complex by simultaneous phosphorylations of RPA at the N-terminus of RPA32 subunit by DNA-PK and of p53 at Ser37 and Ser46 in a Chk1/Chk2-independent manner by ATR and ATM, respectively. Neither the phosphorylation of RPA nor of p53 alone could dissociate p53 and RPA. Furthermore, disruption of the release significantly compromised HR repair of DSBs. Our results reveal a mechanism for the crosstalk between HR repair and NHEJ through the co-regulation of p53-RPA interaction by DNA-PK, ATM and ATR. PMID:22797063

DNA-PK, ATM and ATR collaboratively regulate p53-RPA interaction to facilitate homologous recombination DNA repair.

PubMed

Serrano, M A; Li, Z; Dangeti, M; Musich, P R; Patrick, S; Roginskaya, M; Cartwright, B; Zou, Y

2013-05-09

Homologous recombination (HR) and nonhomologous end joining (NHEJ) are two distinct DNA double-stranded break (DSB) repair pathways. Here, we report that DNA-dependent protein kinase (DNA-PK), the core component of NHEJ, partnering with DNA-damage checkpoint kinases ataxia telangiectasia mutated (ATM) and ATM- and Rad3-related (ATR), regulates HR repair of DSBs. The regulation was accomplished through modulation of the p53 and replication protein A (RPA) interaction. We show that upon DNA damage, p53 and RPA were freed from a p53-RPA complex by simultaneous phosphorylations of RPA at the N-terminus of RPA32 subunit by DNA-PK and of p53 at Ser37 and Ser46 in a Chk1/Chk2-independent manner by ATR and ATM, respectively. Neither the phosphorylation of RPA nor of p53 alone could dissociate p53 and RPA. Furthermore, disruption of the release significantly compromised HR repair of DSBs. Our results reveal a mechanism for the crosstalk between HR repair and NHEJ through the co-regulation of p53-RPA interaction by DNA-PK, ATM and ATR.

Reversal of DDK-Mediated MCM Phosphorylation by Rif1-PP1 Regulates Replication Initiation and Replisome Stability Independently of ATR/Chk1.

PubMed

Alver, Robert C; Chadha, Gaganmeet Singh; Gillespie, Peter J; Blow, J Julian

2017-03-07

Dbf4-dependent kinases (DDKs) are required for the initiation of DNA replication, their essential targets being the MCM2-7 proteins. We show that, in Xenopus laevis egg extracts and human cells, hyper-phosphorylation of DNA-bound Mcm4, but not phosphorylation of Mcm2, correlates with DNA replication. These phosphorylations are differentially affected by the DDK inhibitors PHA-767491 and XL413. We show that DDK-dependent MCM phosphorylation is reversed by protein phosphatase 1 (PP1) targeted to chromatin by Rif1. Loss of Rif1 increased MCM phosphorylation and the rate of replication initiation and also compromised the ability of cells to block initiation when challenged with replication inhibitors. We also provide evidence that Rif1 can mediate MCM dephosphorylation at replication forks and that the stability of dephosphorylated replisomes strongly depends on Chk1 activity. We propose that both replication initiation and replisome stability depend on MCM phosphorylation, which is maintained by a balance of DDK-dependent phosphorylation and Rif1-mediated dephosphorylation. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Thoracoscopic evacuation of retained post-traumatic hemothorax.

PubMed

Ahmad, Tanveer; Ahmed, Syed Waqar; Soomro, Niaz Hussain; Sheikh, Khalil Ahmed

2013-03-01

Post-traumatic retained hemothorax is a major risk factor for empyema thoracis leading to prolonged hospitalization, entrapped lung and a need for decortication. VATS (Video Assisted Thoracoscopy) for retained hemothorax shortens the duration of chest tube drainage and length of stay. From December 2004 to July 2009, 110 consecutive patients underwent VATS for retained or clotted hemothoraces at the Department of Thoracic Surgery, Jinnah Postgraduate Medical Centre, Karachi. Majority of the patients were males (n = 91; 82.7%). Sixty-five patients (59.1%) underwent VATS within 6 days and 45 patients (40.9%) between 7 - 14 days of injury. In 8 patients (7.3%) VATS was abandoned for thoracotomy. Post VATS full lung expansion was achieved in 87 patients (79.0) with complete evacuation of hemothorax. Chest tubes were removed within the first week in 100 patients (90.9%). In hemodynamically stable patients, VATS is a safe, reliable and effective technique for the evacuation of retained hemothorax. Early intervention within 6 days of injury avoids the need for a thoracotomy and is associated with a better short and long-term outcome.

Is breast cancer awareness campaign effective in Pakistan?

PubMed

Soomro, Rufina

2017-07-01

To assess the effectiveness of existing breast cancer awareness strategies in terms of early breast cancer detection.. This descriptive, retrospective study was conducted at the Breast Surgery department of the Liaquat National Hospital, Karachi, and comprised records of all biopsy-proven stage 1 breast cancer patients from 1994 to 2014.All relevant records were retrieved year-wise from computerised database and age and stage of each case at presentation were noted. Data of stage 1 breast cancer patients was calculated in all age groups in absolute numbers and in percentage. The total number of women aged below 40 years and stage 1 patients in each year were counted and percentages were calculated and year-wise plotted and compared with whole group. A total of 8,291 patients were registered during the study period. Their number increased from 53(0.64%) in 1994 to 847(10.21%) in 2014. Over the study period, there was a slow trend towards improvement in early diagnosis of breast cancer. With existing breast cancer awareness strategies, the rate of change for early diagnosis of this deadly disease was very slow.

Frequency of JAK2 V617F mutation in patients with Philadelphia positive Chronic Myeloid Leukemia in Pakistan.

PubMed

Tabassum, Najia; Saboor, Mohammed; Ghani, Rubina; Moinuddin, Moinuddin

2014-01-01

Co-existence of myeloproliferative disorders (MPD) and Janus associated kinase 2 mutation (JAK2 V617F) is a well-established fact. Only few case reports are available showing presence of JAK2 V617F mutation in chronic myeloid leukemia (CML). Purpose of this study was to determine the frequency of JAK2 V617F mutation in Philadelphia Chromosome positive (Ph (+)) CML patients in Pakistan. The study was conducted from August 2009 to July 2010 at Civil Hospital and Baqai Institute of Hematology (BIH) Karachi. Blood samples from 25 patients with CML were collected. Multiplex reverse transcription polymerase chain reaction (RT-PCR) was performed for Breakpoint Cluster Region - Abelson (BCR-ABL) rearrangement. Conventional PCR was performed for JAK2 V617F mutation on BCR-ABL positive samples. All 25 samples showed BCR-ABL rearrangement. Out of these 11 samples (44%) had JAK2 V617F mutation; the remaining 14 (56%) cases showed JAK2 617V wild type. It is concluded that the co-existence of Ph (+)CML and JAK2 V617F mutation is possible.

Obesity with irregular menstrual cycle in young girls.

PubMed

Mustaqeem, M; Sadullah, S; Waqar, W; Farooq, M Z; Khan, A; Fraz, T R

2015-01-01

Obesity is one of the leading causes of morbidity and mortality worldwide. Obese women are at increased risk of developing Type 2 Diabetes, cardiovascular diseases, hyperlipidemia, rectal carcinoma and gynecological problems including sub fertility, menstrual dysfunction and polycystic ovarian disease. The aim of this study was to assess relationship of obesity with menstrual irregularity in young girls that can help to create awareness among young girls about obesity and how it can affect fertility. It was a case controlled cross sectional study comprising of 220 participants from different colleges and universities of Karachi and from outpatients department of private clinic and Civil Hospital Karachi. A questionnaire was designed to assess the relationship of obesity with irregular menstrual cycle. Questionnaires were filled by co-authors after taking verbal consent. Data was collected from March 2013 to December 2013 and entered and analyzed on SPSS 16.0. Out of 220 participants obese and overweight were 67(30.4%) and 49(22.2%) respectively. Significant association was found between body composition and menstrual cycle irregularity as menstrual irregularity was present in only 9.5% when the BMI was normal and 14.09% and 24% girls in the overweight and obese categories respectively. Waist to hip ratio was found increased in 61.36% of girls. Sixty four point forty four percent (64.44%) of the girls with increased waist to hip ratio reported menstrual irregularity which makes 39.55% of the total sample population. Dysmenorrhea was reported by 63.6% of participants and family history was positive in 77.3%. Hirsutism was reported in 36.7% and 49.2%, acne in 34.6% and 43.2%, weight gain tendency in 85.7% and 98.5%, types 2 diabetes in 0% and 4.4% and hypertension in 8.16% and 31.3% of overweight and obese participants respectively. This study shows considerable association between overall and central obesity with menstrual cycle irregularity. This study provides the grounds on which foundation of health promotion and awareness programs can be laid for targeted age group.

Mini-Craniotomy Under Local Anesthesia for Chronic Subdural Hematoma: An Effective Choice for Elderly Patients and for Patients in a Resource-Strained Environment.

PubMed

Mahmood, Shaikh Danish; Waqas, Muhammad; Baig, Mirza Zain; Darbar, Aneela

2017-10-01

Mini-craniotomy for chronic subdural hematoma (CSDH) is associated with lower rates of recurrence. However, the procedure is performed mostly with the patient under general anesthesia (GA) and therefore frequently requires an intensive care unit (ICU) facility, especially in the elderly population. Because of the unavailability of ICU beds, and to avoid GA, we started to perform this procedure with the patient under local anesthesia (LA). This was a retrospective medical chart review conducted in the section of Neurosurgery at the Aga Khan Hospital in Karachi, Pakistan. The study duration was 1 year. We included patients aged 55 years or older undergoing surgery for CSDH. Clinical characteristics, hospital stay, and recurrence rates were compared between 2 groups, local versus general anesthesia. Thirty-five patients underwent mini-craniotomy for CSDH in the study period. Sixteen patients underwent mini-craniotomy under LA versus 19 patients for GA. Median age for the LA group was 67 years compared with 70 years in the GA group. Four patients from the LA group experienced postoperative complications versus 7 from the GA group. Only one patient in the LA group required an ICU bed in the postoperative period. There was no recurrence in LA group. The overall recurrence was 2.86%. Mini-craniotomy for CSDH under LA is an equally effective procedure compared with mini-craniotomy under GA. In addition, it minimizes the risks of GA in the elderly population and obviates the need of a postoperative ICU bed. It also reduces operative time and hospital stay as compared with GA. Copyright © 2017 Elsevier Inc. All rights reserved.

The financial burden of cancer: estimates from patients undergoing cancer care in a tertiary care hospital.

PubMed

Zaidi, Adnan A; Ansari, Tayyaba Z; Khan, Aziz

2012-10-15

The emotional burden associated with the diagnosis of cancer is sometimes overshadowed by financial burden sustained by patient and the family. This is especially relevant for a developing country as there is limited state support for cancer treatment. We conducted this study to estimate the cost of cancer care for two major types of cancer and to assess the perception of patients and families regarding the burden of the cost for undergoing cancer treatment at a private tertiary care hospital. This cross-sectional study was conducted at day care and radiotherapy unit of Aga Khan University, Hospital (AKUH) Karachi, Pakistan. All adult patients with breast and head & neck cancers diagnosed for 3 months or more were included. Data was collected using a structured questionnaire and analysed using SPSS. Sixty seven patients were interviewed during the study period. The mean and median monthly income of these patients was 996.4 USD and 562.5 USD respectively. Comparatively the mean and median monthly cost of cancer care was 1093.13 USD and 946.42 USD respectively. The cost of the treatment either fully or partially was borne by the family in most cases (94%). The financial burden of cancer was perceived as significant by 28 (42%) patients and unmanageable by 18 (27%) patients. This perceived level of burden was associated significantly with average monthly income (p = <0.001). Our study indicates that the financial burden of cancer care is substantial and can be overwhelming. There is a desperate need for treatment support programs either by the government or other welfare organisations to support individuals and families who are already facing a difficult and challenging situation.

Gastroenteritis: A Grass Root Approach.

ERIC Educational Resources Information Center

Dure-Samin, Akram; Mubina, Agboatwalla

1992-01-01

In Karachi, Pakistan, 4 resource personnel disseminated information about sanitation and breastfeeding in the prevention of gastroenteritis to 100 households. Compared to 100 that did not receive health information, the intervention group had less incidence of diarrhea and better use of oral rehydration salt. (SK)

Analysis of hRad1, a Human G2 Checkpoint Control Gene

DTIC Science & Technology

2002-03-01

kinases chk1(+) and cds1(+). Genetics, 1999. 152(4): p. 1501-12. 39. Fritz , E., A.A. Friedl, R.M. Zwacka, F. Eckardt-Schupp, and M.S. Meyn, The yeast...Schiripo, M.M. Jorczak, D.C. Sgroi, J.E. Garber, F.P. Li, K.E. Nichols, J.M. Varley, A.K. Godwin, K.M. Shannon, E. Harlow, and D.A. Haber

The terminal basal mitosis of chicken retinal Lim1 horizontal cells is not sensitive to cisplatin-induced cell cycle arrest.

PubMed

Shirazi Fard, Shahrzad; Thyselius, Malin; All-Ericsson, Charlotta; Hallböök, Finn

2014-01-01

For proper development, cells need to coordinate proliferation and cell cycle-exit. This is mediated by a cascade of proteins making sure that each phase of the cell cycle is controlled before the initiation of the next. Retinal progenitor cells divide during the process of interkinetic nuclear migration, where they undergo S-phase on the basal side, followed by mitoses on the apical side of the neuroepithelium. The final cell cycle of chicken retinal horizontal cells (HCs) is an exception to this general cell cycle behavior. Lim1 expressing (+) horizontal progenitor cells (HPCs) have a heterogenic final cell cycle, with some cells undergoing a terminal mitosis on the basal side of the retina. The results in this study show that this terminal basal mitosis of Lim1+ HPCs is not dependent on Chk1/2 for its regulation compared to retinal cells undergoing interkinetic nuclear migration. Neither activating nor blocking Chk1 had an effect on the basal mitosis of Lim1+ HPCs. Furthermore, the Lim1+ HPCs were not sensitive to cisplatin-induced DNA damage and were able to continue into mitosis in the presence of γ-H2AX without activation of caspase-3. However, Nutlin3a-induced expression of p21 did reduce the mitoses, suggesting the presence of a functional p53/p21 response in HPCs. In contrast, the apical mitoses were blocked upon activation of either Chk1/2 or p21, indicating the importance of these proteins during the process of interkinetic nuclear migration. Inhibiting Cdk1 blocked M-phase transition both for apical and basal mitoses. This confirmed that the cyclin B1-Cdk1 complex was active and functional during the basal mitosis of Lim1+ HPCs. The regulation of the final cell cycle of Lim1+ HPCs is of particular interest since it has been shown that the HCs are able to sustain persistent DNA damage, remain in the cell cycle for an extended period of time and, consequently, survive for months.

Determinants of contraceptives use amongst youth: an exploratory study with family planning service providers in Karachi Pakistan.

PubMed

Nishtar, Noureen Aleem; Sami, Neelofar; Alim, Sabina; Pradhan, Nousheen; Hasnain, Farid Ul

2013-01-05

In Pakistan, Contraceptive Prevalence Rate (CPR) among married female youth is 17.4% and even lower in rural and slum areas leading to rapid population growth on one hand and poor health consequences on the other. The study was conducted to explore family planning service providers' perceptions regarding use of different contraceptive methods and to identify factors that are influencing their use amongst currently married youth aged 18-24 years in slum areas of Karachi. Qualitative exploratory study design was adopted and a total of ten in-depth interviews were conducted with family planning service providers of the area. For content analysis coding of transcribed interviews was done and then categories were made and furthermore themes were derived. Our findings revealed that family planning service providers perceived that there is low use of contraceptive methods amongst youth of study area and low usage could be due to side effects; myths and misconceptions; lack of proper knowledge about different contraceptives; unmet needs of contraceptives; socio-cultural and religious factors about different contraceptive methods and family planning service providers own biases against or for use of contraceptive methods amongst youth in the study area. However better education of youth and family planning service providers' improved knowledge about counseling and use of contraceptive methods was perceived to be associated with improved use of family planning methods amongst youth of the study area. Exaggerated side effects and socio-cultural factors could be important influences leading to low use of family planning methods amongst youth of Karachi. Some policy initiatives are the training of lady health Workers, lady health visitors, physicians and staff of the pharmacies for counseling youth in the correct use of family planning methods.

Assessing reasons for school/college dropout among young adults and implications for awareness about STDs and HIV/AIDS: findings from a population-based study in Karachi, Pakistan.

PubMed

Farid-ul-Hasnain, Syed; Krantz, Gunilla

2011-06-01

Dropping out of school/college not only impedes economic prosperity but may also result in poor knowledge and awareness about sexually transmitted diseases (STDs). This study investigated, among young adults in Karachi, Pakistan, the risk factors associated with involuntary school/college dropout and the implications for awareness about HIV/AIDS and STDs. A population-based, cross-sectional study of 1,650 young males and females, aged 17-21 years and living in Karachi, was conducted using a structured questionnaire. Bivariate and multivariate analyses were performed separately for males and females. Females were twice as likely to drop out of school/college as males. Furthermore, migrant residential status, living in an extended family and lower socio-economic status were identified as risk factors for school/college dropout both for males and females. In the total sample, only 17% of males and 13% of females had heard of STDs (p = 0.020). Furthermore, 26.8% of males and 20.5% of females had not heard of HIV/AIDS (p = 0.003). The females exhibited a higher level of awareness on these matters than the males, irrespective of whether they had dropped out of school or not. While the males who dropped out were considerably less aware than those who remained at school, there was no such difference among females. Young adults from poor families are at increased risk of dropping out of school/college. Among the dropouts, males were clearly at risk of ignorance about STDs while females were somewhat better informed.

An autoregressive integrated moving average model for short-term prediction of hepatitis C virus seropositivity among male volunteer blood donors in Karachi, Pakistan

PubMed Central

Akhtar, Saeed; Rozi, Shafquat

2009-01-01

AIM: To identify the stochastic autoregressive integrated moving average (ARIMA) model for short term forecasting of hepatitis C virus (HCV) seropositivity among volunteer blood donors in Karachi, Pakistan. METHODS: Ninety-six months (1998-2005) data on HCV seropositive cases (1000-1 × month-1) among male volunteer blood donors tested at four major blood banks in Karachi, Pakistan were subjected to ARIMA modeling. Subsequently, a fitted ARIMA model was used to forecast HCV seropositive donors for 91-96 mo to contrast with observed series of the same months. To assess the forecast accuracy, the mean absolute error rate (%) between the observed and predicted HCV seroprevalence was calculated. Finally, a fitted ARIMA model was used for short-term forecasts beyond the observed series. RESULTS: The goodness-of-fit test of the optimum ARIMA (2,1,7) model showed non-significant autocorrelations in the residuals of the model. The forecasts by ARIMA for 91-96 mo closely followed the pattern of observed series for the same months, with mean monthly absolute forecast errors (%) over 6 mo of 6.5%. The short-term forecasts beyond the observed series adequately captured the pattern in the data and showed increasing tendency of HCV seropositivity with a mean ± SD HCV seroprevalence (1000-1 × month-1) of 24.3 ± 1.4 over the forecast interval. CONCLUSION: To curtail HCV spread, public health authorities need to educate communities and health care providers about HCV transmission routes based on known HCV epidemiology in Pakistan and its neighboring countries. Future research may focus on factors associated with hyperendemic levels of HCV infection. PMID:19340903

Benzodiazepine use among adults residing in the urban settlements of Karachi, Pakistan: A cross sectional study

PubMed Central

2011-01-01

Background There are hardly any studies carried out in Pakistan on the usage of benzodiazepines at the level of community. This research was aimed to determine the frequency of benzodiazepine use, along with its associations with socio-demographic and clinical characteristics among community dwelling adults, residing in two urban settlements of Karachi, Pakistan. Methods We performed a cross sectional study from August 2008 to December 2009, in 2 areas of Karachi, namely Garden and Sultanabad. We followed the systematic sampling strategy to randomly select the households, with an adult of either sex and of age 18 years or more. Data collection was carried out through interview, using a pre-tested questionnaire, with items on socio-demographic position, medical history and benzodiazepine use. Student's t-test and χ2 test was employed to determine the associations between socio-demographic and clinical characteristics, and their relationship with benzodiazepine use was determined using applied logistic regression. Results The overall percentage of benzodiazepine consumption was estimated to be 14%. There were significantly more benzodiazepine users in the peri-urban Sultanabad community to the urban community of Garden (p-value = 0.001). The mean age (± SD) for users was 51.3 (± 15.6) years compared to 37.1 (± 14.4) years among non-users. Bromazepam was the most widely used benzodiazepine (29%); followed by diazepam, with a median duration on primary use being 144 weeks (IQR = 48-240). The adjusted logistic regression model revealed that increasing age, location, female sex, unemployment and psychiatric consultation were associated with increased likelihood of benzodiazepine use. Conclusion We believe the unregulated over-the-counter sales of benzodiazepines and social conditions might be playing a role in this high consumption of benzodiazepines in the community. PMID:21801457

Prevalence and determinants of asthma in adult male leather tannery workers in Karachi, Pakistan: A cross sectional study

PubMed Central

Shahzad, Khurram; Akhtar, Saeed; Mahmud, Sadia

2006-01-01

Background This study aimed to estimate the prevalence and to identify some risk factors of adult asthma in male leather tannery workers in Karachi, Pakistan. Methods A cross sectional study was conducted from August 2003 to March 2004 on leather tannery workers of Karachi, Pakistan. Data were collected from 641 workers engaged in 95 different tanneries in Korangi industrial area selected as sample of convenience. Face to face interviews were performed using a structured pre-tested questionnaire by trained data collectors. Results Prevalence of adult asthma was 10.8% (69/641) in this study population. The prevalence of perceived work-related asthma was 5.3% (34/641). Multivariable logistic regression model showed that after taking into account the age effect, the leather tannery worker were more likely to be asthmatic, if they were illiterate (adjusted OR = 2.13, 95% CI: 1.17–3.88), of Pathan ethnicity (adjusted OR = 2.69; 95% CI: 1.35–5.36), ever-smoked (adjusted OR = 2.22, 95% CI: 1.16–4.26), reportedly never used gloves during different tanning tasks (OR = 3.28; 95% CI : 1.72–6.26). Also, the final model showed a significant interaction between perceived allergy and duration of work. Those who perceived to have allergy were more likely to have asthma if their duration of work was 8 years (adjusted OR = 2.26; 95% CI: 1.19 – 4.29) and this relationship was even stronger if duration was 13 years (adjusted OR = 3.67; 95% CI: 1.98–6.79). Conclusion Prevalence of asthma in leather tannery workers appears to be high and is associated with educational status, ethnicity, smoking, glove use, perceived to have allergy and duration of work. PMID:17144930

Prevalence and determinants of asthma in adult male leather tannery workers in Karachi, Pakistan: a cross sectional study.

PubMed

Shahzad, Khurram; Akhtar, Saeed; Mahmud, Sadia

2006-12-05

This study aimed to estimate the prevalence and to identify some risk factors of adult asthma in male leather tannery workers in Karachi, Pakistan. A cross sectional study was conducted from August 2003 to March 2004 on leather tannery workers of Karachi, Pakistan. Data were collected from 641 workers engaged in 95 different tanneries in Korangi industrial area selected as sample of convenience. Face to face interviews were performed using a structured pre-tested questionnaire by trained data collectors. Prevalence of adult asthma was 10.8% (69/641) in this study population. The prevalence of perceived work-related asthma was 5.3% (34/641). Multivariable logistic regression model showed that after taking into account the age effect, the leather tannery worker were more likely to be asthmatic, if they were illiterate (adjusted OR = 2.13, 95% CI: 1.17-3.88), of Pathan ethnicity (adjusted OR = 2.69; 95% CI: 1.35-5.36), ever-smoked (adjusted OR = 2.22, 95% CI: 1.16-4.26), reportedly never used gloves during different tanning tasks (OR = 3.28; 95% CI : 1.72-6.26). Also, the final model showed a significant interaction between perceived allergy and duration of work. Those who perceived to have allergy were more likely to have asthma if their duration of work was 8 years (adjusted OR = 2.26; 95% CI: 1.19 - 4.29) and this relationship was even stronger if duration was 13 years (adjusted OR = 3.67; 95% CI: 1.98-6.79). Prevalence of asthma in leather tannery workers appears to be high and is associated with educational status, ethnicity, smoking, glove use, perceived to have allergy and duration of work.

Impact of a Daily SMS Medication Reminder System on Tuberculosis Treatment Outcomes: A Randomized Controlled Trial.

PubMed

Mohammed, Shama; Glennerster, Rachel; Khan, Aamir J

2016-01-01

The rapid uptake of mobile phones in low and middle-income countries over the past decade has provided public health programs unprecedented access to patients. While programs have used text messages to improve medication adherence, there have been no high-powered trials evaluating their impact on tuberculosis treatment outcomes. To measure the impact of Zindagi SMS, a two-way SMS reminder system, on treatment success of people with drug-sensitive tuberculosis. We conducted a two-arm, parallel design, effectiveness randomized controlled trial in Karachi, Pakistan. Individual participants were randomized to either Zindagi SMS or the control group. Zindagi SMS sent daily SMS reminders to participants and asked them to respond through SMS or missed (unbilled) calls after taking their medication. Non-respondents were sent up to three reminders a day. Public and private sector tuberculosis clinics in Karachi, Pakistan. Newly-diagnosed patients with smear or bacteriologically positive pulmonary tuberculosis who were on treatment for less than two weeks; 15 years of age or older; reported having access to a mobile phone; and intended to live in Karachi throughout treatment were eligible to participate. We enrolled 2,207 participants, with 1,110 randomized to Zindagi SMS and 1,097 to the control group. The primary outcome was clinically recorded treatment success based upon intention-to-treat. We found no significant difference between the Zindagi SMS or control groups for treatment success (719 or 83% vs. 903 or 83%, respectively, p = 0·782). There was no significant program effect on self-reported medication adherence reported during unannounced visits during treatment. In this large-scale randomized controlled effectiveness trial of SMS medication reminders for tuberculosis treatment, we found no significant impact. The trial was registered with ClinicalTrials.gov, NCT01690754.

Determinants of Contraceptives Use amongst Youth: An Exploratory Study with Family Planning Service Providers in Karachi Pakistan

PubMed Central

Nishtar, Noureen Aleem; Sami, Neelofar; Alim, Sabina; Pradhan, Nousheen; Farid-Ul-Hasnain

2013-01-01

Introduction: In Pakistan, Contraceptive Prevalence Rate (CPR) among married female youth is 17.4% and even lower in rural and slum areas leading to rapid population growth on one hand and poor health consequences on the other. The study was conducted to explore family planning service providers’ perceptions regarding use of different contraceptive methods and to identify factors that are influencing their use amongst currently married youth aged 18-24 years in slum areas of Karachi. Method: Qualitative exploratory study design was adopted and a total of ten in-depth interviews were conducted with family planning service providers of the area. For content analysis coding of transcribed interviews was done and then categories were made and furthermore themes were derived. Results: Our findings revealed that family planning service providers perceived that there is low use of contraceptive methods amongst youth of study area and low usage could be due to side effects; myths and misconceptions; lack of proper knowledge about different contraceptives; unmet needs of contraceptives; socio-cultural and religious factors about different contraceptive methods and family planning service providers own biases against or for use of contraceptive methods amongst youth in the study area. However better education of youth and family planning service providers’ improved knowledge about counseling and use of contraceptive methods was perceived to be associated with improved use of family planning methods amongst youth of the study area. Conclusion: Exaggerated side effects and socio-cultural factors could be important influences leading to low use of family planning methods amongst youth of Karachi. Some policy initiatives are the training of lady health Workers, lady health visitors, physicians and staff of the pharmacies for counseling youth in the correct use of family planning methods. PMID:23618469

Knowledge, attitude and practices regarding HIV/AIDS among adult fishermen in coastal areas of Karachi

PubMed Central

2014-01-01

Background Migrant populations are at high risk of Human Immuno Deficiency Virus infection (HIV) and Acquired Immunodeficiency Syndrome (AIDS). Studies of HIV/AIDS knowledge, attitudes and practices among fishermen in developing countries have shown gaps in knowledge and fear of contagion with ambivalent attitudes towards HIV/AIDS and inconsistent universal precautions adherence. The aim of this study was to determine the knowledge, attitude and practices regarding HIV/AIDS among adult fishermen in a coastal area of Karachi, Pakistan. Methods Community based cross sectional study was conducted among fishermen in coastal area of Karachi from June to September 2012. A total of 297 adult fishermen were selected by using simple random sampling technique from different sectors of coastal village. Data were collected using a structured validated questionnaire. The frequency distribution of both dependent and independent variables were worked out. Comparisons of knowledge, attitude and practices regarding HIV/AIDS by socio-demographic characteristics were made using logistic regression. Results Out of 297 fishermen, majority had in-appropriate knowledge (93.6%), negative attitude (75.8%) and less adherent sexual practices (91.6%). In univariate analysis, lower education and higher income were significantly associated (OR 2.25, 95% CI, 1.11, 4.55), (OR = 3.04 CI 1.03-9.02, p value 0.04) with negative attitude and un-safe practices towards HIV/AIDS respectively, whereas no significant association of socio-economic characteristics with knowledge, attitude and practices were observed in multivariate analysis. Conclusions This study suggests that fishermen had very poor knowledge, negative attitudes towards HIV and AIDS and had unsafe sexual practices which suggest that they lack the basic understanding of HIV/AIDS infection. Extensive health education campaign should be provided to the vulnerable sections of the society for the control of HIV/AIDS. PMID:24886122

Parental perceptions surrounding polio and self-reported non-participation in polio supplementary immunization activities in Karachi, Pakistan: a mixed methods study.

PubMed

Khowaja, Asif Raza; Khan, Sher Ali; Nizam, Naveeda; Omer, Saad Bin; Zaidi, Anita

2012-11-01

To assess parent's knowledge and perceptions surrounding polio and polio vaccination, self-reported participation in polio supplementary immunization activities (SIAs) targeting children aged < 5 years, and reasons for non-participation. The mixed methods study began with a cross-sectional survey in Karachi, Pakistan. A structured questionnaire was administered to assess parental knowledge of polio and participation in polio SIAs conducted in September and October 2011. Additionally, 30 parents of Pashtun ethnicity (a high-risk group) who refused to vaccinate their children were interviewed in depth to determine why. Descriptive and bivariate analyses by ethnic and socioeconomic group were performed for quantitative data; thematic analysis was conducted for qualitative interviews with Pashtun parents. Of 1017 parents surveyed, 412 (41%) had never heard of polio; 132 (13%) did not participate in one SIA and 157 (15.4%) did not participate in either SIA. Among non-participants, 34 (21.6%) reported not having been contacted by a vaccinator; 116 (73.9%) reported having refused to participate, and 7 (4.5%) reported that the child was absent from home when the vaccinator visited. Refusals clustered in low-income Pashtun (43/441; 9.8%) and high-income families of any ethnic background (71/153; 46.4%). Low-income Pashtuns were more likely to not have participated in polio SIAs than low-income non-Pashtuns (odds ratio, OR: 7.1; 95% confidence interval, CI: 3.47-14.5). Reasons commonly cited among Pashtuns for refusing vaccination included fear of sterility; lack of faith in the polio vaccine; scepticism about the vaccination programme, and fear that the vaccine might contain religiously forbidden ingredients. In Karachi, interruption of polio transmission requires integrated and participatory community interventions targeting high-risk populations.

To Explore the Experiences of Women on Reasons in Initiating and Maintaining Breastfeeding in Urban Area of Karachi, Pakistan: An Exploratory Study

PubMed Central

Shaheen Premani, Zahra; Kurji, Zohra; Mithani, Yasmin

2011-01-01

This is an exploratory study that explores the experiences of lactating women in initiating, continuing, or discontinuing breastfeeding in an urban area of Karachi, Pakistan. Objectives. To explore the experiences of lactating women and to understand their support and hindering mechanisms in initiating and maintaining breastfeeding. Methods. This is an exploratory design assisting in exploring the participant's experiences of initiating and maintaining breastfeeding to better understand their world. Purposive sampling was used, and data was analyzed through manual thematic analysis. Results. The data revealed that mother's knowledge, sociocultural environment, breastfeeding decision, and self- and professional support acted as driving forces for the participants. However, sociocultural environment, physiological changes, time management, and being a housewife to breastfeed their children were all challenges and barriers that the participants thought hindered their breastfeeding initiation and maintenance. Conclusion. Breastfeeding is a natural but taxing phenomenon, and breastfeeding mothers experience supporting and hindering factors in initiating and maintaining breastfeeding. PMID:22389780

Young adults' perceptions on life prospects and gender roles as important factors to influence health behaviour: a qualitative study from Karachi, Pakistan.

PubMed

Hasnain, Syed Farid-ul; Johansson, Eva; Mogren, Ingrid; Krantz, Gunilla

2012-04-28

The purpose of this qualitative study was to explore perceptions and expectations of young males and females, in Karachi, Pakistan, regarding their life prospects and gender roles, with resulting implications for health behaviour. The main theme emerging was "Young adults' prospects in life are hampered by psychosocial and gender equality constraints". Gender inequality and the low status of women in society were described as major obstacles to the overall development. Persistent withholding of information to the younger generation on sexual and reproductive health issues was perceived to increase exposure to health risks, particularly sexually transmitted infections (STIs). The present study reveals new discourses on equality among young adults, pointing towards an increasing, sound interaction between the sexes and aspirations for more gender equal relationships. Such views and awareness among the younger generation constitutes a strong force towards change of traditional norms, including reproductive health behaviour, and calls for policy change.

India-Pakistan Border at Night

NASA Image and Video Library

2017-12-08

An astronaut aboard the International Space Station took this nighttime panorama while looking north across Pakistan’s Indus River valley. The port city of Karachi is the bright cluster of lights facing the Arabian Sea, which appears completely black. City lights and the dark color of dense agriculture closely track with the great curves of the Indus valley. For scale, the distance from Karachi to the foothills of the Himalaya Mountains is 1,160 kilometers (720 miles). This photograph shows one of the few places on Earth where an international boundary can be seen at night. The winding border between Pakistan and India is lit by security lights that have a distinct orange tone. Astronaut photograph ISS045-E-27869 was acquired on September 23, 2015, with a Nikon D4 digital camera using a 28 millimeter lens, and is provided by the ISS Crew Earth Observations Facility and the Earth Science and Remote Sensing Unit, Johnson Space Center. via NASA Earth Observatory Read more: earthobservatory.nasa.gov/IOTD/view.php?id=86725&eocn...

Frequency, character and predisposing factor of headache among students of medical college of Karachi.

PubMed

Noor, Tooba; Sajjad, Ali; Asma, Anoosha

2016-02-01

To evaluate the frequency, predisposing factors and symptomatology of headache among medical students. The cross-sectional study was conducted from September to December 2013 and comprised students of two medical colleges of Karachi. International Classification of Headache Disorder-II criterion was used to diagnose and classify headache. SPSS 17 was used for statistical analysis. Of the 413 medical students studies, 326(79%) had tension type headache, and 87 (21%) had migraine. Headache was more frequent among females than males, with a ratio of 6.5:1. Both types of headache were significantly associated with self-reported disturbed sleep pattern, stress and various triggering factors (p<0.05 each). Both types greatly influenced individual's daily life with significant association with avoiding academics, extra-curricular activities, family and friends (p<0.05 each). High self-medication rate of 400(96.9%) was observed. The prevalence of headache among medical students was high with female predominance. Infrequent consultation needs to be addressed through awareness programmes.

Human papilloma virus--role in precancerous and cancerous oral lesions of tobacco chewers.

PubMed

Zil-A-Rubab; Baig, Saeeda; Siddiqui, Ayesha; Nayeem, Amena; Salman, Mohammad; Qidwai, Moiz Ahmed; Mallick, Raiya; Qidwai, Samrah

2013-10-01

Human papilloma viruses (HPV), members of the papillomaviridae family, infects squamous epithelial cells of cevix, lower genitalia, and oral cavity. The association of HPV with oropharyngeal carcinogenesis is well documented.The incidence of oral cancer ranks second in Karachi South in both genders according to World Health Organization (WHO) statistics. This is attributed to the popularity of chewable tobacco products among the general population. Studies on Gutka-eaters in a set population of Karachi showed high frequency of HPV (17%) and high prevalence of HPV in squamous cell carcinoma in Pakistani patients (68%). The exposure of oral mucosa to chewable tobacco causes abrasions making it susceptible to HPV. This review strives to summarise the role of HPV in chewable tobacco-related precancerous and cancerous lesions. The literature of about a decade was retrieved from Google and pubMed with the under mentioned key words. It was found that the use of chewable tobacco products, especially Gutka, may increase the risk of oral squamous cell carcinoma (OSCC).

Patient Attitudes towards Physician Nonverbal Behaviors during Consultancy: Result from a Developing Country

PubMed Central

Khan, Fahad Hanif; Hanif, Raheela; Tabassum, Rumina

2014-01-01

Background. Nonverbal behaviors have a significant impact on patients during consultations. This study was undertaken to find out the attitudes and preferences of the patients regarding nonverbal communication during consultations with physicians, in a tertiary care hospital. Methods. A questionnaire based cross-sectional study was carried out at the Aga Khan University Hospital, Karachi, Pakistan, during the months of January to March 2012. All patients (>18 years of age) coming for consultancy in the family medicine clinics were approached; out of 133, 120 agreed to participate. The subjects were asked questions regarding physician's comforting touch and eye contact and their responses were noted. The data were analyzed using SPSS and chi-square test was used to identify corelations. Results. Overall, 120 patients were enrolled. About 58.3% were men and 41.7% were women with a mean age of 34.9 ± 10.9 years. 95.8% were Muslims and 57.6% had more than 12 years of education. Among females 74% wanted supportive touch from doctors, used to comfort the patient (45%) or to show respect (27.5%) or as healing (30%). 86.1% of the respondents believe that establishing eye contact with the patient shows that the doctor is attentive towards his/her patient. The eye contact should be brief but regular (54.1%) and prolonged staring (36.7%) makes them uncomfortable. Conclusion. Nonverbal communication helps to strengthen the doctor-patient relation as patients do appreciate positive touch and eye contact from their physicians. PMID:24977140

Frequency of colistin and fosfomycin resistance in carbapenem-resistant Enterobacteriaceae from a tertiary care hospital in Karachi.

PubMed

Qamar, Salima; Shaheen, Najma; Shakoor, Sadia; Farooqi, Joveria; Jabeen, Kauser; Hasan, Rumina

2017-01-01

Management of infections with carbapenem-resistant Enterobacteriaceae (CRE) is challenging. In recent times, agents such as colistin and fosfomycin have been used in combination with other antibiotics to treat such infections. In this study, we aim to seek frequency of colistin and fosfomycin resistance in CRE from Pakistan. This study was conducted at clinical laboratories, Aga Khan University Hospital. In total, 251 CRE were included in the study. Colistin minimum inhibitory concentrations (MICs) were performed using broth microdilution (BMD) method and VITEK ® 2 system, whereas fosfomycin susceptibility was performed using Kirby-Bauer method. MIC 50 and MIC 90 were calculated for colistin and agreement between VITEK and BMD was also calculated. Out of 251 strains colistin MIC of ≥4 µg/mL was seen in 40 (15.9%). Of these strains 20 (50%) were Klebsiella pneumoniae . Colistin MIC 50 and MIC 90 were found to be 0.5 and 16 µg/mL, respectively. BMD and VITEK 2 showed 100% categorical agreement. Essential agreement was 88.5% with kappa score 0.733 indicating strong agreement between VITEK and BMD. 31 out of 251 (12.3%) CREs were resistant to fosfomycin. Study shows frequency of colistin and fosfomycin resistance to be 15.9% and 12.3%, respectively. In countries where rate of CREs is high, emerging resistance against these last resort antibiotics is alarming as it leaves clinicians with almost no options to manage such multidrug resistant and extensively drug resistant infections.

Hearing Status after Radical Mastoidectomy without Tympanoplasty.

PubMed

Khan, Shamaila Nawaz; Udaipurwala, Iqbal Hussain; Mehmood, Talat; Rahat, Zahid Mehmood

2017-12-01

To find out the impairment of hearing associated with radical mastoidectomy by measuring the quantitative difference in the functional hearing level before and after radical mastoidectomy operation without tympanoplasty. Cross-sectional comparative study. Department of Otorhinolaryngology and Head Neck Surgery, Bahawal Victoria Hospital, Bahawalpur and PNS Shifa Hospital, Karachi, from November 2009 to January 2013. Eighty-five patients, diagnosed clinically as chronic suppurative otitis media with extensive cholesteatoma having history of ear discharge and hearing impairment for more than 6 weeks duration and requiring radical mastoidectomy for treatment, were included in this study. Pure tone audiogram was done before and after radical mastoidectomy. Hearing impairment was compared in each patient before and after the operation. Among the 85 patients, 54 (63.5%) were males and 31 (36.5%) were females, with the age ranged between 18 to 63 years, mean age being 42.31 4.8 years. The mean increase in hearing loss after radical mastoidectomy in air conduction was 7.19 dB, bone conduction was 4.16 dB, and air-bone gap was 3.75 dB (0.001). The ear became dry and safe in 82 patients (96.5%) out of a total of 85, and only 3 patients required revision surgery at a second stage. Radical mastoidectomy has a least negligible effect on hearing status and one should not limit this technique due to the concern of aggravated hearing in patients with extensive cholesteatoma at the cost of dry and safe ears, which should be of prime importance.

Quality of Life in Individuals Surgically Treated for Congenital Hydrocephalus During Infancy: A Single-Institution Experience.

PubMed

Khan, Saad Akhtar; Khan, Muhammad Faheem; Bakhshi, Saqib Kamran; Irfan, Omar; Khan, Hamza Abdur Rahim; Abbas, Asad; Awan, Safia; Bari, Muhammad Ehsan

2017-05-01

Congenital hydrocephalus (CH) is a frequently encountered birth anomaly that can hinder long-term neurologic maturity and social well-being of affected children. This study was undertaken to assess quality of life (QOL) 10-15 years after surgical treatment for primary CH during infancy at a tertiary care hospital in a developing country. This retrospective cohort study included individuals who presented to Aga Khan University Hospital, Karachi, Pakistan, between 1995 and 2005 at <1 year old and underwent surgery for primary CH. The Hydrocephalus Outcome Questionnaire was used to assess outcomes with respect to QOL. Of 118 patients, 90 patients participated in the study. Mean age at first admission was 6.2 months. Mean length of follow-up was 5.4 years. Of these, 28 patients had died after surgery. Shunt infection (P = 0.012) and delayed milestones (P = 0.003) were found to be statistically significant factors affecting mortality in the patients who died. The mean overall health score was 0.67 ± 0.30. Age <6 months at the time of first surgery was a poor predictor of overall health on the Hydrocephalus Outcome Questionnaire (P = 0.039). In our analysis, we assessed the QOL associated with CH. We hope that these results will provide insight for future prospective work with the ultimate goal of improving long-term QOL in children with CH. Copyright © 2017 Elsevier Inc. All rights reserved.

Source apportionment of particulate matter in a South Asian Mega City: A case study of Karachi

NASA Astrophysics Data System (ADS)

Shahid, imran

2016-04-01

Pakistan is facing unabated air pollution as a major issue and its cities are more vulnerable as compared to urban centers in the developed world. During the last few decades, there has been a rapid increase in population, urbanization, industrialization, transportation and other human activities. In year June 2015 heat wave in largest South Asian mega city Karachi more than 1500 people died in one week. Unfortunately no air quality monitoring system is operation in any city of Pakistan. There is a sharp increase in both the variety and quantity of air pollutants and their corresponding sources. In this study contributions of different sources to particulate matter concentration has estimated in urban area of Karachi. Carbonaceous species (elemental carbon, organic carbon, carbonate carbon), soluble ions (Ca++, Mg++, Na+, K+, NH4+, Cl-, NO3-, SO4--), saccharides (levoglucosan, galactosan, mannosan, sucrose, fructose, glucose, arabitol and mannitol) were measured in atmospheric fine (PM2.5) and coarse (PM10) particles collected under pre-monsoon conditions (March - April 2009) at an urban site in Karachi (Pakistan). Average concentrations of PM2.5 were 75μg/m3 and of PM10 437μg/m3. The large difference between PM10 and PM2.5 originated predominantly from mineral dust. "Calcareous dust" and „siliceous dust" were the overall dominating material in PM, with 46% contribution to PM2.5 and 78% to PM10-2.5. 20 Combustion particles and secondary organics (EC+OM) comprised 23% of PM2.5 and 6% of PM10-2.5. EC, as well as OC ambient levels were higher (59% and 56%) in PM10-2.5 than in 22 PM2.5. Biomass burning contributed about 3% to PM2.5, and had a share of about 13% of "EC+OM" in PM2.5. The impact of bioaerosol (fungal spores) was minor and had a share of 1 and 2% of the OC in the PM2.5 and PM10-2.5 size fractions. Of secondary inorganic constituents (NH4)2SO4 contributes 4.4% to PM2.5 and no detectable quantity to PM10-2.5. The sea salt contribution is about 2% both to PM2.5 and PM10-2.5. In order to make air quality better and risk free in South Asian cities a comprehensive and integrated regional effort is required that include continuous air quality monitoring, source apportionment and implementation of regional air quality policies.

Involvement of 53BP1, a p53 Binding Protein, in Chk2 Phosphyorylation of p53 and DNA Damage Cell Cycle Checkpoints

DTIC Science & Technology

2006-05-01

between 53BP1 and the platelet derived growth factor (PDGF) was recently identified in a patient with a myeloproliferative disorder.32 The 53BP1-PDGF...receptor beta in a patient with a t(5;15)(q33;q22) and an imatinib-responsive eosinophilic myeloproliferative disorder. Cancer Res 2004; 64:7216-9

Potentiation of tumor responses to DNA damaging therapy by the selective ATR inhibitor VX-970

PubMed Central

Boucher, Diane M.; Eustace, Brenda; Gu, Yong; Hare, Brian; Johnson, Mac A.; Milton, Sean; Murphy, Cheryl E.; Takemoto, Darin; Tolman, Crystal; Wood, Mark; Charlton, Peter; Charrier, Jean-Damien; Furey, Brinley; Golec, Julian; Reaper, Philip M.; Pollard, John R.

2014-01-01

Platinum-based DNA-damaging chemotherapy is standard-of-care for most patients with lung cancer but outcomes remain poor. This has been attributed, in part, to the highly effective repair network known as the DNA-damage response (DDR). ATR kinase is a critical regulator of this pathway, and its inhibition has been shown to sensitize some cancer, but not normal, cells in vitro to DNA damaging agents. However, there are limited in vivo proof-of-concept data for ATR inhibition. To address this we profiled VX-970, the first clinical ATR inhibitor, in a series of in vitro and in vivo lung cancer models and compared it with an inhibitor of the downstream kinase Chk1. VX-970 markedly sensitized a large proportion of a lung cancer cell line and primary tumor panel in vitro to multiple DNA damaging drugs with clear differences to Chk1 inhibition observed. In vivo VX-970 blocked ATR activity in tumors and dramatically enhanced the efficacy of cisplatin across a panel of patient derived primary lung xenografts. The combination led to complete tumor growth inhibition in three cisplatin-insensitive models and durable tumor regression in a cisplatin-sensitive model. These data provide a strong rationale for the clinical evaluation of VX-970 in lung cancer patients. PMID:25010037

Potentiation of tumor responses to DNA damaging therapy by the selective ATR inhibitor VX-970.

PubMed

Hall, Amy B; Newsome, Dave; Wang, Yuxin; Boucher, Diane M; Eustace, Brenda; Gu, Yong; Hare, Brian; Johnson, Mac A; Milton, Sean; Murphy, Cheryl E; Takemoto, Darin; Tolman, Crystal; Wood, Mark; Charlton, Peter; Charrier, Jean-Damien; Furey, Brinley; Golec, Julian; Reaper, Philip M; Pollard, John R

2014-07-30

Platinum-based DNA-damaging chemotherapy is standard-of-care for most patients with lung cancer but outcomes remain poor. This has been attributed, in part, to the highly effective repair network known as the DNA-damage response (DDR). ATR kinase is a critical regulator of this pathway, and its inhibition has been shown to sensitize some cancer, but not normal, cells in vitro to DNA damaging agents. However, there are limited in vivo proof-of-concept data for ATR inhibition. To address this we profiled VX-970, the first clinical ATR inhibitor, in a series of in vitro and in vivo lung cancer models and compared it with an inhibitor of the downstream kinase Chk1. VX-970 markedly sensitized a large proportion of a lung cancer cell line and primary tumor panel in vitro to multiple DNA damaging drugs with clear differences to Chk1 inhibition observed. In vivo VX-970 blocked ATR activity in tumors and dramatically enhanced the efficacy of cisplatin across a panel of patient derived primary lung xenografts. The combination led to complete tumor growth inhibition in three cisplatin-insensitive models and durable tumor regression in a cisplatin-sensitive model. These data provide a strong rationale for the clinical evaluation of VX-970 in lung cancer patients.

Recovery from DNA damage-induced G2 arrest requires actin-binding protein filamin-A/actin-binding protein 280.

PubMed

Meng, Xiangbing; Yuan, Yuan; Maestas, Adrian; Shen, Zhiyuan

2004-02-13

Filamin-A (filamin-1) is an actin-binding protein involved in the organization of actin networks. Our previous study shows that filamin-A interacts with BRCA2, and lack of filamin-A expression results in increased cellular sensitivity to several DNA damaging agents in melanoma cells (Yuan, Y., and Shen, Z. (2001) J. Biol. Chem. 276, 48318-48324), suggesting a role of filamin-A in DNA damage response. In this report, we demonstrated that deficiency of filamin-A results in an 8-h delay in the recovery from G2 arrest in response to ionizing radiation. However, filamin-A deficiency does not affect the initial activation of the G2/M checkpoint. We also found that filamin-A deficiency results in sustained activation of Chk1 and Chk2 after irradiation. This in turn causes a delay in the dephosphorylation of phospho-Cdc2, which is inhibitory to the G2/M transition. In addition, filamin-A-deficient M2 cells undergo mitotic catastrophe-related nuclear fragmentation after they are released from the G2 arrest. Together, these data suggest a functional role of filamin-A in the recovery from G2 arrest and subsequent mitotic cell death after DNA damage.

An ATR-dependent function for the Ddx19 RNA helicase in nuclear R-loop metabolism.

PubMed

Hodroj, Dana; Recolin, Bénédicte; Serhal, Kamar; Martinez, Susan; Tsanov, Nikolay; Abou Merhi, Raghida; Maiorano, Domenico

2017-05-02

Coordination between transcription and replication is crucial in the maintenance of genome integrity. Disturbance of these processes leads to accumulation of aberrant DNA:RNA hybrids (R-loops) that, if unresolved, generate DNA damage and genomic instability. Here we report a novel, unexpected role for the nucleopore-associated mRNA export factor Ddx19 in removing nuclear R-loops formed upon replication stress or DNA damage. We show, in live cells, that Ddx19 transiently relocalizes from the nucleopore to the nucleus upon DNA damage, in an ATR/Chk1-dependent manner, and that Ddx19 nuclear relocalization is required to clear R-loops. Ddx19 depletion induces R-loop accumulation, proliferation-dependent DNA damage and defects in replication fork progression. Further, we show that Ddx19 resolves R-loops in vitro via its helicase activity. Furthermore, mutation of a residue phosphorylated by Chk1 in Ddx19 disrupts its interaction with Nup214 and allows its nuclear relocalization. Finally, we show that Ddx19 operates in resolving R-loops independently of the RNA helicase senataxin. Altogether these observations put forward a novel, ATR-dependent function for Ddx19 in R-loop metabolism to preserve genome integrity in mammalian cells. © 2017 The Authors.

Oxoaporphine Metal Complexes (CoII, NiII, ZnII) with High Antitumor Activity by Inducing Mitochondria-Mediated Apoptosis and S-phase Arrest in HepG2

PubMed Central

Qin, Jiao-Lan; Shen, Wen-Ying; Chen, Zhen-Feng; Zhao, Li-Fang; Qin, Qi-Pin; Yu, Yan-Cheng; Liang, Hong

2017-01-01

Three new oxoaporphine Co(II), Ni(II) and Zn(II) complexes 1–3 have been synthesized and fully characterized. 1–3 have similar mononuclear structures with the metal and ligand ratio of 1:2. 1–3 exhibited higher cytotoxicity than the OD ligand and cisplatin against HepG2, T-24, BEL-7404, MGC80–3 and SK-OV-3/DDP cells, with IC50 value of 0.23−4.31 μM. Interestingly, 0.5 μM 1–3 significantly caused HepG2 arrest at S-phase, which was associated with the up-regulation of p53, p21, p27, Chk1 and Chk2 proteins, and decrease in cyclin A, CDK2, Cdc25A, PCNA proteins. In addition, 1–3 induced HepG2 apoptosis via a caspase-dependent mitochondrion pathway as evidenced by p53 activation, ROS production, Bax up-regulation and Bcl-2 down-regulation, mitochondrial dysfunction, cytochrome c release, caspase activation and PARP cleavage. Furthermore, 3 inhibited tumor growth in HepG2 xenograft model, and displayed more safety profile in vivo than cisplatin. PMID:28436418

In Vitro Antiproliferative Effect of Arthrocnemum indicum Extracts on Caco-2 Cancer Cells through Cell Cycle Control and Related Phenol LC-TOF-MS Identification

PubMed Central

Boulaaba, Mondher; Mkadmini, Khaoula; Tsolmon, Soninkhishig; Han, Junkyu; Smaoui, Abderrazak; Kawada, Kiyokazu; Ksouri, Riadh; Isoda, Hiroko; Abdelly, Chedly

2013-01-01

This study aimed to determinate phenolic contents and antioxidant activities of the halophyte Arthrocnemum indicum shoot extracts. Moreover, the anticancer effect of this plant on human colon cancer cells and the likely underlying mechanisms were also investigated, and the major phenols were identified by LC-ESI-TOF-MS. Results showed that shoot extracts had an antiproliferative effect of about 55% as compared to the control and were characterised by substantial total polyphenol content (19 mg GAE/g DW) and high antioxidant activity (IC50 = 40 μg/mL for DPPH test). DAPI staining revealed that these extracts decrease DNA synthesis and reduce the proliferation of Caco-2 cells which were stopped at the G2/M phase. The changes in the cell-cycle-associated proteins (cyclin B1, p38, Erk1/2, Chk1, and Chk2) correlate with the changes in cell cycle distribution. Eight phenolic compounds were also identified. In conclusion, A. indicum showed interesting antioxidant capacities associated with a significant antiproliferative effect explained by a cell cycle blocking at the G2/M phase. Taken together, these data suggest that A. indicum could be a promising candidate species as a source of anticancer molecules. PMID:24348703

Targeting telomere-containing chromosome ends with a near-infrared femtosecond laser to study the activation of the DNA damage response and DNA damage repair pathways

PubMed Central

Silva, Bárbara Alcaraz; Stambaugh, Jessica R.

2013-01-01

Abstract. Telomeres are at the ends of chromosomes. Previous evidence suggests that laser-induced deoxyribose nucleic acid (DNA) breaks at chromosome ends during anaphase results in delayed cytokinesis. A possible explanation for this delay is that the DNA damage response (DDR) mechanism has been activated. We describe a live imaging method to study the effects of DDR activation following focal point near-infrared femtosecond laser microirradiation either at a single chromosome end or at a chromosome arm in mitotic anaphase cells. Laser microirradiation is used in combination with dual fluorescent labeling to monitor the co-localization of double-strand break marker γH2AX along with the DDR factors in PtK2 (Potorous tridactylus) cells. Laser-induced DNA breaks in chromosome ends as well as in chromosome arms results in recruitment of the following: poly(ADP-ribose) polymerase 1, checkpoint sensors (p-Chk1, p-Chk2), DNA repair protein Ku70/Ku80, and proliferating cell nuclear antigen. However, phosphorylated p53 at serine 15 is detected only at chromosome ends and not at chromosome arms. Full activation of DDR on damaged chromosome ends may explain previously published results that showed the delay of cytokinesis. PMID:24064949

Radiotherapy induces cell cycle arrest and cell apoptosis in nasopharyngeal carcinoma via the ATM and Smad pathways.

PubMed

Li, Ming-Yi; Liu, Jin-Quan; Chen, Dong-Ping; Li, Zhou-Yu; Qi, Bin; He, Lu; Yu, Yi; Yin, Wen-Jin; Wang, Meng-Yao; Lin, Ling

2017-09-02

Nasopharyngeal carcinoma (NPC) is a common malignant neoplasm of the head and neck which is harmful to human's health. Radiotherapy is commonly used in the treatment of NPC and it induces immediate cell cycle arrest and cell apoptosis. However, the mechanism remains unknown. Evidences suggested the activation of Ataxia telangiectasia mutated (ATM) pathway and Smad pathway are 2 of the important crucial mediators in the function of radiotherapy. In this study, we performed in vitro assays with human nasopharyngeal carcinoma CNE-2 cells and in vivo assays with nude mice to investigate the role of the ATM and Smad pathways in the treatment of nasopharyngeal carcinoma with radiotherapy. The results suggested that radiation induced activation of ATM pathway by inducing expression of p-ATM, p-CHK1, p-CHK2, p15 and inhibiting expression of p-Smad3. In addition, Caspase3 expression was increased while CDC25A was decreased, leading to cell cycle arrest and cell apoptosis. On the other hand, activation of Smad3 can inhibited the ATM pathway and attenuated the efficacy of radiation. In summary, we suggest that both ATM and Smad pathways contribute to the cell cycle arrest and cell apoptosis during nasopharyngeal carcinoma cells treated with radiation.

Anthocyanins Delay Ageing-Related Degenerative Changes in the Liver.

PubMed

Wei, Jie; Zhang, Guokun; Zhang, Xiao; Xu, Dexin; Gao, Jun; Fan, Jungang

2017-12-01

Liver ageing is a significant risk factor for chronic liver diseases. Anthocyanin is a food additive that has previously shown efficacy in increasing longevity. Here, we tested whether anthocyanins could protect young mice from accelerated ageing of the liver. Kunming mice were injected with D-galactose to accelerate ageing and were given 20 or 40 mg/kg anthocyanins as an intervention. After eight weeks, whole liver function and structure were evaluated, and the expression levels of genes involved in the DNA damage signalling pathway were assessed by Western blot analysis. Anthocyanins delayed the reduction of the liver index (p < 0.05), hepatic tissue injury and fibrosis. Anthocyanins also maintained the stability of the redox system (GSH-PX, T-SOD and MDA) in plasma and liver structures (p < 0.001) and reduced the levels of inflammatory factors (IL-1, IL-6 and TNF-α) in the liver (p < 0.05). Moreover, the expression levels of sensors (ATM and ATR), mediators (H2AX and γ-H2AX) and effectors (Chk1, Chk2, p53 and p-p53) in the DNA damage signalling pathway were all reduced. Anthocyanins could be widely used in the field of health products to slow ageing-related deterioration of liver function and structure by inhibiting DNA damage.

75 FR 69742 - Designation of Three Individuals and One Entity Pursuant to Executive Order 13224

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-15

..., Pakistan; Office 22, Third Floor, al Fatah Plaza, Commerical Market, Rawalpindi, Pakistan; Room No. 22, 3rd Floor, al-Fateh Plaza, Commerical Market Road, Chandi Chowk, Rawalpindi, Pakistan; Karachi, Pakistan; Nelam Road, Bandi Chehza, Muzaffarabad, Pakistan; Balakot, Besyan Chouk, Pakistan; Rajana Road, Srah...

75 FR 21151 - Designation of Two Individuals Pursuant to Executive Order 13224

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-22

..., Pakistan; DOB 5 Oct 1951; POB Azamgarh, Uttar Pradesh, India; nationality Pakistan; Passport KZ 550207 (Pakistan); alt. Passport G154297 (Pakistan); alt. Passport KC550207 (Pakistan) (individual) [SDGT]. 2...; a.k.a. ``USTAAD SHEHEB''), Karachi, Pakistan; DOB circa 1955; alt. DOB circa 1964; POB Sarghoda...

76 FR 61776 - Designation of Five Individuals Pursuant to Executive Order 13224

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-05

...''), Boghra Road, Miralzei Village, Chaman, Baluchistan Province, Pakistan; DOB 1966; alt. DOB 1961; alt. DOB.... YAMIN, Abdur Rehman Muhammad; a.k.a. ``ABDULLAH SINDHI''), Karachi, Pakistan; DOB 3 Oct 1965; POB Mirpur Khas, Pakistan; nationality Pakistan; National ID No. 44103- 5251752-5 (Pakistan); Passport CV9157521...

Exploring Perceptions of University Students Pertaining to Grades over Knowledge and Skills

ERIC Educational Resources Information Center

Hasnain, Asma; Bhamani, Shelina

2014-01-01

The aim of the research was to study the phenomenon surrounding the perspective of university students preferring grades to knowledge and skills. Three currently enrolled participants were selected from different private universities of Karachi. Participants' interviews were examined through thematic analysis. The findings suggested that students…

School Leadership in Pakistan: Exploring the Headteacher's Role.

ERIC Educational Resources Information Center

Simkins, Tim; Sisun, Charles; Memon, Muhammand

2003-01-01

Explores the nature of school leadership in Pakistan by drawing on two studies describing experiences of headteachers in Karachi. Identifies three determinants of personal efficacy of headteachers: The powers and accountability of the school system, community expectations within the context of the national culture, and the individual's personality…

Makran Mountain Range, Indus River Valley, Pakistan, India

NASA Image and Video Library

1984-10-13

41G-120-040 (5-13 Oct. 1984) --- Pakistan, featuring the city of Karachi, the Makran mountain range, the mouth of the Indus River and the North Arabian Sea were photographed with a medium format camera aboard the space shuttle Challenger during the 41-G mission. Photo credit: NASA

Evaluation of World View-2 Satellite Data for Mapping Seaweed Beds Along Karachi Coast

NASA Astrophysics Data System (ADS)

Danish Siddiqui, Muhammad; Abdullah, Muhammad

2016-07-01

INTRODUCTION One of the important components for the coastal system are seaweeds. Seaweed provides numerous ecosystem facilities such as; habitats, fishing nursery grounds, feed production for aquatic biota, and ability to absorb nutrients such as nitrogen and phosphorus and carbon fixation for seawater purification. It's an important coastal resource that has great economic potential due to its utilization in food, cosmetics and industrial products. It also plays an important role in aquaculture and fish breeding. The habitats of many sea species rely on seaweeds for their shelter and food requirements. Seaweed resources are present along Pakistan coastal areas mainly around Karachi shoreline and there exists a potential market for seaweed in the country that is yet untapped. Not only this but the seaweed resources in Pakistan are still unexplored and unmapped. The need to preserve and map seaweed sites along Karachi coast is, cannot be overlooked due to the economic potential of seaweed. To protect marine biodiversity, regular monitoring and mapping of seaweeds are important in order to regulate their growth and their dependent species to maintain their biological associations. The main purpose of this study is to map naturally existing seaweed resources along the Karachi coast and identify the environmental parameters which impact seaweed growth in coastal waters of Karachi using geospatial techniques. To estimate marine resources such as seaweed over a certain area using traditional methods require an extensive amount of labor, cost and time. Remote sensing techniques, on the other hand, offer a good alternative to performing studies on a larger scale using minimum resources as compared to the conventional methods. DATA AND DATA SOURCES WorldView-2 images of 2 meter multispectral and 0.5 meter panchromatic and MODIS (Moderate Resolution Imaging Spectroradiometer) daily composite of Sea Surface Temperature (SST) product of 250 meter resolutions are used in this study. STUDY AREA Buleji, a small coastal village along Karachi coast in the country of Pakistan, is selected for this study. At this side seaweed resources are present. Its center lies at a latitude of 24o 51' 20" and a longitude of 66o 48' 24.2" METHODOLOGY In this research, high-resolution Worldview -2 satellite data have been used.WorldView-2 delivers 1.85 meter multispectral and 0.46 meter panchromatic images. A 0.5 meter multispectral pan sharpened image was developed by fusing these two images. Indices, such as normalized difference vegetative index (NDVI) and another index developed through spectral signatures, have been applied on worldview-2 imagery. Image enhancement technique, principal component analysis (PCA) is applied on the same image. Bathymetry map of the study area has been composed by relative bathymetry remote sensing technique. This map is later verified by the depth nautical chart and found satisfactory. For assessment of environmental parameters, freely available MODIS daily SST product has been acquired. MODIS product was converted to tiff (Tagged Image File Format) format and projected for further processing. SST image was reclassified using GIS technique and was overlaid on satellite images to detect the favorable temperature range for seaweed growth. CONCLUSION Since the macro-habitats and benthic communities around Pakistan coastline have not yet been properly mapped and defined, this study will be an outline for the protection of marine biodiversity and habitat of many sea species which rely on seaweeds for their sustenance. Regular monitoring and mapping are important to regulate the growth of seaweeds and their dependent species to maintain their biological associations which will eventually maintain the equilibrium among various species in the marine ecosystem. Seaweed is also important for the production of many consumable items and with proper import/export policies its marketing can ultimately help strengthen the country's economy. Seaweed yield estimations can be useful for fishermen, policy makers, and food, pharmaceutical and cosmetic companies. . In Pakistan, remote sensing data have not yet extensively used for coastal resource mapping and, therefore, a very few studies could be found on this subject in the literature. This study will, hopefully, not only be an addition to the exiting pool of knowledge but will have practical usefulness for many stakeholders.

Instrumentation Purchased

DTIC Science & Technology

1984-08-01

0V-10 on 100/120 mesh chromosorb W column was used in the gas chromatography inlet of the mass spectrometer. High resolution mass spectra were obtained...into methylsilene on ultraviolet irradiation in an argon matrix, as well’as, in the gas phase at high temperature has been reported. 31 34 .4 . CH3 CHK... analytical achievement. Further it should be noted that in control experiments we have shown that the products discussed are stable to the pyrolysis

Mammalian Homologs of Yeast Checkpoint Genes

DTIC Science & Technology

2001-07-01

previous cycle we developed systems and reagents for expression and analysis of all of the pertinent proteins, and are made headway on association of Chk2...function, with emphasis on p53 regulation, cell cycle regulation, and complementation of ATM defects. Saccharomyces Schizosaceharomy Homo sapiens...RAD53, two essential genes, play a central role in DNA damage checkpoints at all cell cycle stages. Our lab showed that Rad9 is a regulator coupling DNA

CHK2, A Candidate Prostate Cancer Susceptibility Gene

DTIC Science & Technology

2005-01-01

novel FBN1 mutations, polymor- 1298-1304 phisms, and sequence variants in Marfan syndrome and re- Boddy MN, Furnari B, Mondesert 0, Russell P (1998...2001) or have suggested only a limited prone syndromes , such as Li-Fraumeni syndrome (LFS role in hereditary prostate cancer (Rebbeck et al. 2000...prostate cancer or other malig- with prostate cancer carried the Ile157Thr mutation. nancies occurring in LFS or LFS-like syndromes later in However

CHK2, A Candidate Prostate Cancer Susceptibility Gene

DTIC Science & Technology

2003-01-01

To identify prostate cancer susceptibility genes, we applied a mutation screening of candidate gene approach. We screened for mutations in CHEK2 , the...families, 400 sporadic cases, and 423 unaffected men as control. A total of 28 (4.8%) germline CHEK2 mutations were found among 578 patients and...additional 11 in 9 families. Sixteen of 18 unique CHEK2 mutations identified in this study were not detected among 423 unaffected men, suggesting a

78 FR 52823 - Designation of 1 Individual and 1 Entity Pursuant to Executive Order 13224 of September 23, 2001...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-26

.... UMAR, Muhammad), Karachi, Pakistan; Miram Shah, North Waziristan Agency, Federally Administered Tribal Areas, Pakistan; DOB 1977; POB Saudi Arabia; nationality Pakistan; National ID No. 466-77-221879 (Pakistan); alt. National ID No. 42201-015024707-7 (individual) [SDGT]. Entity 1. JAMIA TALEEM-UL-QURAN-WAL...

Identifying Core Vocabulary for Urdu Language Speakers Using Augmentative Alternative Communication

ERIC Educational Resources Information Center

Mukati, Abdul Samad

2013-01-01

The purpose of this research is to identify a core set of vocabulary used by native Urdu language (UL) speakers during dyadic conversation for social interaction and relationship building. This study was conducted in Karachi, Pakistan at an institution of higher education. This research seeks to distinguish between general (nonspecific…

Facebook Is a Source of Social Capital Building among University Students: Evidence From a Developing Country

ERIC Educational Resources Information Center

Raza, Syed Ali; Qazi, Wasim; Umer, Amna

2017-01-01

This study analyzes the influence of Facebook usage on building social capital among university students in Karachi by using a modified framework of technology acceptance model. Important information was gathered utilizing organized questionnaire containing items of Facebook intensity, social self-efficacy, perceived ease of use, perceived…

Impact of CNG Crisis on Student's Academic Life

ERIC Educational Resources Information Center

Azeem, Kiran; Nadeem, Wajiha; Zia, Afsa; Shehzad, Shiza; Anwar, Zara

2017-01-01

The goal of this study is to determine the impact of Compressed Natural Gas (CNG) crisis on Student's Academic Life of Karachi Pakistan. This research helps in observing the behavior of students and their educational progress includes depression and anxiety, rate of absenteeism and undesirable results in exams threatens due to CNG crisis and…

Head Teachers and Teachers as Pioneers in Facilitating Dyslexic Children in Primary Mainstream Schools

ERIC Educational Resources Information Center

Jaka, Fahima Salman

2015-01-01

This study explores the perceptions of school heads and teachers in facilitating young dyslexic children in primary mainstream schools of Pakistan. Through purposive sampling, the researcher selected eight participants: Four primary school heads and four primary teachers from elite schools of Karachi. The research instrument selected for this…

Young Adults’ Perceptions on Life Prospects and Gender Roles as Important Factors to Influence Health Behaviour: A Qualitative Study from Karachi, Pakistan

PubMed Central

Farid-ul-Hasnain, Syed; Johansson, Eva; Mogren, Ingrid; Krantz, Gunilla

2012-01-01

The purpose of this qualitative study was to explore perceptions and expectations of young males and females, in Karachi, Pakistan, regarding their life prospects and gender roles, with resulting implications for health behaviour. The main theme emerging was “Young adults’ prospects in life are hampered by psychosocial and gender equality constraints”. Gender inequality and the low status of women in society were described as major obstacles to the prosperity and development. Persistent withholding of information to the younger generation on sexual and reproductive health issues was perceived to increase exposure to health risks, particularly sexually transmitted infections (STIs). The present study reveals new discourses on equality among young adults, pointing towards an increasing, sound interaction between the sexes and aspirations for more gender equal relationships. The study further reveals serious misconceptions about HIV/AIDS. Such views and awareness among the younger generation constitutes a strong force towards change of traditional norms, including reproductive health behaviour, and calls for policy change. PMID:22980235

Isolation of potentially pathogenic fungi from selected pigeons' feeding sites in Karachi: A new dimension to health hazard.

PubMed

Naz, Sehar Afshan; Yaseen, Muhammad; Jabeen, Nusrat; Shafique, Maryam

2017-06-01

To determine the presence of pathogenic fungal strains in areas where pigeons are present in a large number. This study was conducted at the Federal Urdu University of Arts, Science and Technology, Karachi, from February 2015 to March2016, and comprised samples of soil contaminated with pigeons' excreta. The samples were collected from 20 different pigeon-feeding places in the city. These samples were processed for the isolation and identification of fungi by using standard conventional methods. The fungal strains isolated were also tested for their susceptibility to commonly used antifungal agents by disc diffusion technique. There were 105 samples. A wide variety of fungal strains belonging to different genera of Aspergillus, Rhizopus, Penicillium, Fusarium and Candida were isolated and identified by using conventional methods. The antifungal resistance pattern of these strains also depicts emergence of resistance against commonly used antifungal agents such as amphotericin B and fluconazole. The soil and air of places densely populated with pigeons were found to be loaded with fungal spores and many of them were potential pathogens.

Practices of self-medication with antibiotics among nursing students of Institute of Nursing, Dow University of Health Sciences, Karachi, Pakistan.

PubMed

Ali, Akbar Shoukat; Ahmed, Javed; Ali, Akbar Shoukat; Sonekhi, Gomand Beekho; Fayyaz, Nargis; Zainulabdin, Zeeshan; Jindani, Rahim

2016-02-01

Self-medication practice among nursing students is of growing concern. Access to drugs and handling them in their future practices make nursing students susceptible to self-prescription and self-medication. This cross-sectional study assesses the prevalence and pattern of self-medication with antibiotics among nursing students of Institute of Nursing, Dow University of Health Sciences, Karachi, Pakistan. A random sample of convenience of 160 nursing students underwent a predesigned questionnaire. More than half of nursing students 79 (52.7%) experienced self-medication with antibiotics. It was more prevalent among males 49 (62%) . Knowledge about the drug 59 (74.7%) and convenience 13 (16.5%) were the key reasons to self-medicate. Fever 37 (46.8%) and sore throat 27 (34.2%) were the common symptoms predisposing to self-medication. Beta-lactam group of antibiotics 35 (44.3%) was most frequent used. Only 26 (32.9%) respondents completed the entire antibiotic course. Efforts must be directed towards educating nursing students about responsible and informed self-medication practices.

Malignant head and neck tumours in Radiology Department JPMC Karachi -- a tertiary care experience.

PubMed

Kadri, Shazia; Uddin, Sami; Ahmed, Naveed; Mahmood, Tariq

2015-08-01

To study age, gender and sites of malignant head and neck tumours on contrast-enhanced computed tomography and to elucidate its role. The retrospective study was conducted at the Jinnah Postgraduate Medical Centre, Karachi, and comprised data of patients with histologically proven malignant head and neck tumours reporting from February 2013 to February 2014. Contrast enhanced computed tomography with puffed cheek technique was done in cases of oral cancer, while routine contrast computed tomography was done in cases of other head and neck tumours. SPSS 19 was used for statistical analysis. A total of 100 biopsy-proven cases of malignant tumours comprised the study sample. The male: female ratio was 1.5:1 with an overall mean age of 46.4±16-76 years. . The most common histopathologically proven tumour was squamous cell carcinoma affecting oral mucosa 43(43%), followed by larynx 27(27%) and pharynx 10(10%) . Oral squamous cell carcinoma was the commonest tumour. Compute tomography scan with puffed cheek technique played a beneficial role in locating the site of primary tumour.

Risk factors associated with typhoid fever in children aged 2-16 years in Karachi, Pakistan.

PubMed

Khan, M I; Ochiai, R L; Soofi, S B; Von-Seidlein, L; Khan, M J; Sahito, S M; Habib, M A; Puri, M K; Park, J K; You, Y A; Ali, M; Nizami, S Q; Acosta, C J; Bradley-Sack, R; Clemens, J D; Bhutta, Z A

2012-04-01

We analysed the data from the control group in a typhoid vaccine trial in Karachi to assess the differences in individual-, household- and cluster-level characteristics for developing typhoid fever. The annual incidence of typhoid in children aged 2-16 years in the control arm of the vaccine trial was 151/100 000 population. After adjustment, the risk of typhoid was lower with increasing age [risk ratio (RR) 0·89, 95% confidence interval (CI) 0·83-0·95], was higher with an increase in population density (RR 1·13, 95% CI 1·05-1·21) and was lower in the households using a safe drinking-water source (RR 0·63, 95% CI 0·41-0·99). Typhoid fever affects younger children living in areas of high population density and lack of access to safe water in Pakistan. A combination of environmental and biological interventions is required to prevent the continued epidemiological and economic impact of typhoid fever in high-risk areas of Pakistan.

Urban and rural comparison of vitamin D status in Pakistani pregnant women and neonates.

PubMed

Anwar, S; Iqbal, M P; Azam, I; Habib, A; Bhutta, S; Soofi, S B; Bhutta, Z A

2016-01-01

We undertook a cross-sectional study in rural Jehlum and urban Karachi to evaluate the prevalence of vitamin D deficiency in Pakistani pregnant women and neonates and to assess any association of serum 25(OH) vitamin D [25(OH)D] concentration with vitamin D binding protein (Gc) genotypes. Altogether, 390 women and 266 neonates were recruited from urban and rural sites, respectively. Serum 25(OH)D was measured by an immunoassay, while Gc genotypes were identified using polymerase chain reaction followed by restriction fragment length polymorphism or PCR-RFLP. One-way analysis of variance or ANOVA and linear regression were used for statistical analysis. In urban Karachi, 99.5% of women and 97.3% of neonates were vitamin D deficient (< 50 nmol/L), while 89% of women and 82% of neonates were deficient in rural Jehlum. Gc genotypes were not associated with serum 25(OH)D concentrations in both women and their neonates. We conclude that vitamin D deficiency is highly prevalent in Pakistani women and their neonates, and Gc genotypes are not associated with serum 25(OH)D concentrations.

Frequency and associated risk factors for neck pain among software engineers in Karachi, Pakistan.

PubMed

Rasim Ul Hasanat, Mohammad; Ali, Syed Shahzad; Rasheed, Abdur; Khan, Muhammad

2017-07-01

To determine the frequency of neck pain and its association with risk factors among software engineers. This descriptive, cross-sectional study was conducted at the Dow University of Health Sciences, Karachi, from February to March 2016, and comprised software engineers from 19 different locations. Non-probability purposive sampling technique was used to select individuals spending at least 6 hours in front of computer screens every day and having a work experience of at least 6 months. Data were collected using a self-administrable questionnaire. SPSS 21 was used for data analysis. Of the 185 participants, 49(26.5%) had neck pain at the time of data-gathering, while 136(73.5%) reported no pain. However, 119(64.32%) participants had a previous history of neck pain. Other factors like smoking, physical inactivity, history of any muscular pain and neck pain, uncomfortable workstation, and work-related mental stress and insufficient sleep at night, were found to be significantly associated with current neck pain (p<0.05 each). Intensive computer users are likely to experience at least one episode of computer-associated neck pain.

A quality of care issue: appropriate use and efficacy knowledge of five contraceptive methods: views of men and women living in low socioeconomic settlements of Karachi, Pakistan.

PubMed

Fikree, Fariyal F; Saleem, Sarah; Sami, Neelofar

2005-09-01

To assess knowledge regarding availability, affordability, appropriate use and efficacy for five non-permanent contraceptive methods. Married Muslim women and men (500 each) were randomly selected from two low socioeconomic settlements in Karachi, Pakistan. Interviews to assess their knowledge on a range of contraceptive and abortion themes were conducted. Four hundred men and 357 women were selected from this larger sample based on their knowledge of condoms, withdrawal, oral pills, injectables and IUDs. Nearly half of the sampled men (56%) and women (48%) were contraceptive users. Knowledge regarding contraception, a specific method, its availability and affordability was high. Appropriate use knowledge for condoms was 73% among men (users 78%, non-users 60%; p-value < or = 0.001 ) and 5% among women. Efficacy knowledge was generally poor. Low knowledge levels regarding appropriate use and efficacy even among contraceptive users suggests, that quality of family planning services should not be limited to service delivery issues but extend to appropriate use and efficacy knowledge levels among clients.

Frequency of ABH secretors and non secretors: A cross sectional study in Karachi.

PubMed

Saboor, Muhammad; Ullah, Aman; Qamar, Khansa; Mir, Awal; Moinuddin

2014-01-01

ABO blood group and secretor status is valuable in relation to some diseases in clinical and forensic medicine. Across the globe there are geographic and racial differences in the frequency of secretors and non-secretors. Aim of this study was to evaluate the status of ABH blood group secretors and non-secretors in Karachi (Pakistan). Blood and saliva samples were randomly collected from one hundred and one (n=101) healthy adult students (76 male, 25 female) ranging in age from 15 to 40 years. Their ABO and Rhesus blood groups were determined by conventional methods, and their secretor status was studied by hemagglutination inhibition method of saliva. RESULTS showed that 64.4% of the study population were ABH blood group secretors while 35.6% were non-secretors. Frequencies of the secretor status among various ABO blood groups were 71.4% in group A, 79.5% in group B, 45.5% in group AB, and 61.5% in group O. Frequency of ABH secretor is high (64.4%). Blood group B has the highest secretor (79.5%) frequency while Blood group AB has the lowest (45.5%).

The Frequency of Enterobius Vermicularis Infections in Patients Diagnosed With Acute Appendicitis in Pakistan.

PubMed

Ahmed, Muhammad Umer; Bilal, Muhammad; Anis, Khurram; Khan, Ali Mahmood; Fatima, Kaneez; Ahmed, Iqbal; Khatri, Ali Mohammad; Shafiq-ur-Rehman

2015-02-24

The main aim of this study was to determine the frequency of Enterobius vermicularis infections and other unique histopathological findings in patients diagnosed with acute appendicitis. This retrospective study was conducted in a tertiary care hospital of Karachi, Pakistan over a time period of 9 years from 2005 to 2013. The recorded demographic and histopathological data for the 2956 appendectomies performed during this time frame were extracted using a structured template form. Negative and incidental appendectomies were excluded from the study. Out of the 2956 patients diagnosed with acute appendicitis, 84 (2.8%) patients had Enterobius vermicularis infections. Malignancy (n=2, 0.1%) and infection with Ascaris (n=1, 0.1%) was found very rarely among the patients.Eggs in lumen (n=22, 0.7%), mucinous cystadenoma (n=28, 1.0%), mucocele (n=11, 0.4%), lymphoma (n=9, 0.3%), obstruction in lumen (n=17, 0.6%) and purulent exudate (n=37, 1.3%) were also seldom seen in the histopathological reports. Enterobius vermicularis manifestation is a rare overall but a leading parasitic cause of appendicitis. Steps such as early diagnosis and regular de worming may help eradicate the need for surgeries.

Identifying needs and barriers to diabetes education in patients with diabetes.

PubMed

Rafique, Ghazala; Shaikh, Furqan

2006-08-01

To assess the needs, awareness and barriers to diabetes education for self management and to facilitate the initiation of an education programme promoting self care among diabetics and their families. A qualitative study was conducted among adult diabetics attending outpatient clinics in a tertiary care teaching hospital in Karachi, Pakistan. Semi-structured interviews were conducted on 27 subjects (11 men; 16 women) to identify dominant themes and priority issues. Participants displayed great deal of variation with respect to level of knowledge and motivation for education. Most believed that diabetes was caused by stress. Family was perceived to be a source of positive support. Relative ease of adherence to pharmacological regimens as compared to diet and exercise was reported. Participants expressed frustration at chronicity of disease and fear of developing certain specific complications and inheritance by their children. Barriers to enhancing knowledge included 'No need for further information', distance from training institutions and other priorities. Knowledge, beliefs and fears about diabetes, family influence and accessibility of healthcare, affects management behaviours and learning. Understanding needs and expectations of people with diabetes is essential in initiating and improving the outcomes of education programme for diabetes self care.

Fibromyalgia complicating disease management in rheumatoid arthritis.

PubMed

Abbasi, Lubna; Haidri, Fakhir Raza

2014-06-01

To evaluate frequency of fibromyalgia in rheumatoid arthritis and its effect on disease activity score. Cross-sectional study. The Indus Hospital, Karachi, from December 2010 to May 2011. All adult patients of either gender diagnosed as rheumatoid arthritis on the basis of clinical, laboratory and X-ray criteria were included in the study. The sample data was separated into two groups depending on presence or absence of fibromyalgia and 28 joint disease activity score (DAS-28) value was evaluated. There were 31 (25.83%) patients with rheumatoid arthritis and fibromyalgia (RAFM) out of the total 120. The median (IQR) age of patients was 40 (32 - 51) years. All were females. The overall female frequency was 79 (88.8%). The median (IQR) DAS-28 score in RA group was 4.9 (3.66 - 5.71), while the median (IQR) DAS-28 score in RAFM was 7.04 (6.62 - 7.64) [p < 0.0001]. The number of patient getting combination therapy of DMARD in RAFM group was 61.3% while in RA group was 42.7%. DAS-28 was found to be significantly higher in RAFM patients probably because of higher perception of pain.

Selective lymphadenectomy in endometrial cancer: Retrospective analysis of morbidity and survival data at a tertiary care centre

PubMed Central

Chishti, Uzma; Aziz, Aliya B.; Akhtar, Munazza; Sheikh, Sana

2015-01-01

Objective: To compare perioperative morbidity and survival data between patients with early-stage endometrial cancer who did or did not undergo selective lymphadenectomy. Methods: Retrospective analysis of 180 patients with early-stage endometrial carcinoma treated between 1999 and 2008 was performed in Aga Khan University Hospital, Karachi, Pakistan. Results: Data from 180 patients were analysed. The selective lymphadenectomy group contained 108 women (60%) and the no lymphadenectomy group contained 72 women (40%). The median number of lymph nodes removed was 9. The mean age and extent of disease, as assessed by staging, tumour size, myometrial invasion, and lymphovascular invasion were comparable between groups. Upstaging of the disease to stage 3 and 4 occurred in 11% of patients in the lymphadenectomy group. There were no significant differences in the medical or surgical complications between groups. At a median follow-up of 26 months, both groups had comparable survival (lymphadenectomy versus no lymphadenectomy: 34 versus 32 months). Similar survival was noted for patients who underwent the removal of more or less than 5 pelvic lymph nodes. Conclusion: Selective lymphadenectomy offers the advantage of improved surgical staging but no therapeutic benefit in terms of overall survival. PMID:26430436

The Frequency of Enterobius Vermicularis Infections in Patients Diagnosed With Acute Appendicitis in Pakistan

PubMed Central

Ahmed, Muhammad Umer; Bilal, Muhammad; Anis, Khurram; Khan, Ali Mahmood; Fatima, Kaneez; Ahmed, Iqbal; Khatri, Ali Mohammad; Shafiq-ur-Rehman

2015-01-01

Introduction: The main aim of this study was to determine the frequency of Enterobius Vermicularis infections and other unique histopathological findings in patients diagnosed with acute appendicitis. Materials: This retrospective study was conducted in a tertiary care hospital of Karachi, Pakistan over a time period of 9 years from 2005 to 2013. The recorded demographic and histopathological data for the 2956 appendectomies performed during this time frame were extracted using a structured template form. Negative and incidental appendectomies were excluded from the study. Results: Out of the 2956 patients diagnosed with acute appendicitis, 84 (2.8%) patients had Enterobius Vermicularis infections. Malignancy (n=2, 0.1%) and infection with Ascaris (n=1, 0.1%) was found very rarely among the patients. Eggs in lumen (n=22, 0.7%), mucinous cystadenoma (n=28, 1.0%), mucocele (n=11, 0.4%), lymphoma (n=9, 0.3%), obstruction in lumen (n=17, 0.6%) and purulent exudate (n=37, 1.3%) were also seldom seen in the histopathological reports. Conclusion: Enterobius Vermicularis manifestation is a rare overall but a leading parasitic cause of appendicitis. Steps such as early diagnosis and regular de worming may help eradicate the need for surgeries. PMID:26156929

Alkaline phosphatase as a screening test for osteomalacia.

PubMed

Chinoy, Muhammad Amin; Javed, Muhammad Imran; Khan, Alamzeb; Sadruddin, Nooruddin

2011-01-01

Vitamin D deficiency remains common in children and adults in Pakistan despite adequate sunlight exposure. Diagnosis in adults is usually delayed and is made following pathological fractures that result in significant morbidity. The objective of this study was to see whether Serum Alkaline Phosphatase levels could be used as a screening test for osteomalacia. The Study was conducted at Fatima Hospital, Baqai Medical University, Gadap, Karachi, between July 2002 and June 2005. Serum calcium levels are commonly used to screen patients suspected of osteomalacia, and raised serum alkaline phosphatase (SALP) is considered a diagnostic finding. We used SALP to screen patients who presented with back or non-specific aches and pain of more than six months duration. Three hundred thirty-four (334) patients were screened of which 116 (35%) had raised SALP. Osteomalacia was diagnosed in 92 (79.3%) of these 116 either by plain radiographs, bone biopsy or isotope bone scan. Fifty-four (53.4%) of the 101 cases had a normal level of serum calcium. Osteomalacia is likely to be missed if only serum calcium is used to screen patients. Serum Alkaline Phosphate should be used as the preferred method for screening these patients.

Severity of burn and its related factors: A study from the developing country Pakistan.

PubMed

Adil, Syed Omair; Nisar, Nighat; Ehmer-Al-Ibran; Shafique, Kashif; Baig-Ansari, Naila

2016-06-01

Burns are leading cause of fatal injuries and major cause of morbidity and mortality in developing countries. The major obstacle in controlling severity is factors related to burn. This study determines frequency of burns and the factors related to it in Karachi, Pakistan. A cross-sectional study was conducted and 384 hospitalized adult patients with burns were consecutively interviewed during August 2013 to February 2014. Information was collected on socio-demographic profile, intent of burn, severity of burn, health hazards, physical and psychological characteristics. TBSA burn of >15% was considered as higher severity of burn. Higher severity of burns was found in 76.3% patients. Multivariate analysis showed that higher severity of burns were significantly associated with age less than 25 years (OR 2.7, 95% CI 1.5-4.9), never had been to school (OR 3.1, 95% CI 1.7-5.9) and intentional burn (OR 20.6, 95% CI 5.0-84.9). Majority of patients had higher severity of burn. The intent of injury was intentional, age less than 25 years and no schooling were found significantly associated with higher severity of burns. Copyright © 2016 Elsevier Ltd and ISBI. All rights reserved.

Surgical management of inflammatory bowel disease: A low prevalence, developing country perspective.

PubMed

Nasim, Sana; Chawla, Tabish; Murtaza, Ghulam

2016-03-01

To determine the outcomes of surgical management of inflammatory bowel disease. The retrospective case series was conducted at Aga Khan University Hospital, Karachi, and comprised medical record of adult patients operated between January 1986 and December 2010 for inflammatory bowel disease. Outcomes consisted of complications till last follow-up and 30-day mortality (disease or procedure related). Functional status of patients with ileal pouch was determined via telephone. SPSS 16 was used to analyse data. Of the 36 patients whose records were reviewed, 21(58%) were males, and body mass index was less than 23 in 34(91%). A total of 27(75%) patients underwent elective surgery for their condition. Ileal pouch was formed in 9(25%). Overall mortality was 14(38.8%). Overall incidence of complications was 26(72%), with wound infection being the most common early morbidity in 11(30.5%). Late morbidity included pouchitisin 4/9 (44.9%) and strictures 2/36 (5.5%).On telephonic follow-up, 6 of the remaining 7patients (85%) with ileal pouch were satisfied with the functional results of the procedure. The retrospective case series represents results from a developing country with low prevalence of inflammatory bowel disease and hence limited experience.

Frequency of JAK2 V617F mutation in patients with Philadelphia positive Chronic Myeloid Leukemia in Pakistan

PubMed Central

Tabassum, Najia; Saboor, Mohammed; Ghani, Rubina; Moinuddin, Moinuddin

2014-01-01

Background and Objective: Co-existence of myeloproliferative disorders (MPD) and Janus associated kinase 2 mutation (JAK2 V617F) is a well-established fact. Only few case reports are available showing presence of JAK2 V617F mutation in chronic myeloid leukemia (CML). Purpose of this study was to determine the frequency of JAK2 V617F mutation in Philadelphia Chromosome positive (Ph +) CML patients in Pakistan. Methods: The study was conducted from August 2009 to July 2010 at Civil Hospital and Baqai Institute of Hematology (BIH) Karachi. Blood samples from 25 patients with CML were collected. Multiplex reverse transcription polymerase chain reaction (RT-PCR) was performed for Breakpoint Cluster Region – Abelson (BCR-ABL) rearrangement. Conventional PCR was performed for JAK2 V617F mutation on BCR-ABL positive samples. Results: All 25 samples showed BCR-ABL rearrangement. Out of these 11 samples (44%) had JAK2 V617F mutation; the remaining 14 (56%) cases showed JAK2 617V wild type. Conclusion: It is concluded that the co-existence of Ph +CML and JAK2 V617F mutation is possible. PMID:24639858

Heterogeneity of BCR-ABL rearrangement in patients with chronic myeloid leukemia in Pakistan.

PubMed

Tabassum, Najia; Saboor, Mohammad; Ghani, Rubina; Moinuddin, Moinuddin

2014-07-01

Breakpoint cluster region-Abelson (BCR-ABL) rearrangement or Philadelphia (Ph) chromosome in Chronic Myeloid Leukemia (CML) is derived from a reciprocal chromosomal translocation between ABL gene on chromosome 9 and BCR gene on chromosome 22. This chimeric protein has various sizes and therefore different clinical behaviour. The purpose of this study was to determine the heterogeneity of BCR-ABL rearrangement in patients with Ph(+)CML in Pakistan. The study was conducted at Civil Hospital and Baqai Institute of Hematology (BIH) Karachi. Blood samples from 25 patients with CML were collected. Multiplex reverse transcription polymerase chain reaction (RT-PCR) was performed to identify various BCR-ABL transcripts. All 25 samples showed BCR-ABL rearrangements. Out of these, 24 (96%) patients expressed p210 BCR-ABL rearrangements i.e. 60% (n=15) had b3a2 and 32% (n=8) had b2a2 rearrangements. Co-expression of b3a2 /b2a2 rearrangement and p190 (e1a3) rearrangement was also identified in two patients. It is apparent that majority of the patients had p210 BCR-ABL rearrangements. Frequency of co-expression and rare fusion transcripts was very low.

Chemical characterization and mass closure of PM10 and PM2.5 at an urban site in Karachi - Pakistan

NASA Astrophysics Data System (ADS)

Shahid, Imran; Kistler, Magdalena; Mukhtar, Azam; Ghauri, Badar M.; Ramirez-Santa Cruz, Carlos; Bauer, Heidi; Puxbaum, Hans

2016-03-01

A mass balance method is applied to assess main source contributions to PM2.5 and PM10 levels in Karachi. Carbonaceous species (elemental carbon, organic carbon, carbonate carbon), soluble ions (Ca++, Mg++, Na+, K+, NH4+, Cl-, NO3-, SO4-), saccharides (levoglucosan, galactosan, mannosan, sucrose, fructose, glucose, arabitol and mannitol) were determined in atmospheric fine (PM2.5) and coarse (PM10) aerosol samples collected under pre-monsoon conditions (March-April 2009) at an urban site in Karachi (Pakistan). The concentrations of PM2.5 and PM10 were found to be 75 μg/m3 and 437 μg/m3 respectively. The large difference between PM10 and PM2.5 originated predominantly from mineral dust. "Calcareous dust" and "siliceous dust" were the over all dominating material in PM, with 46% contribution to PM2.5 and 78% to PM10-2.5. Combustion particles and secondary organics (EC + OM) comprised 23% of PM2.5 and 6% of PM10-2.5. EC, as well as OC ambient levels were higher (59% and 56%) in PM10-2.5 than in PM2.5. Biomass burning contributed about 3% to PM2.5, and had a share of about 13% of ;EC + OM; in PM2.5. The impact of bioaerosol (fungal spores) was minor and had a share of 1 and 2% of the OC in the PM2.5 and PM10-2.5 size fractions. In case of secondary inorganic aerosols, ammonium sulphate (NH4)2SO4 contributes 4.4% to PM2.5 and no detectable quantity were found in fraction PM10-2.5. The sea salt contribution is about 2% both to PM2.5 and PM10-2.5.

Missed Immunization Opportunities Among Children Under 5 Years Of Age Dwelling In Karachi City.

PubMed

Khaliq, Asif; Sayed, Sayeeda Amber; Hussaini, Syed Abdullah; Azam, Kiran; Qamar, Mehak

2017-01-01

Immunization is the safest and effective measure for preventing and eradicating various communicable diseases. A glaring immunization gap exists between developing and industrialized countries towards immunization, because the developing countries including Pakistan are still striving to provide basic immunization to their children. The purpose of this study was to access the prevalence and factors of missing immunization among under 5-year children of Karachi.. A cross sectional study was conducted from June 2015 to October 2015 among different outpatient clinics of Karachi. Parents who had child less than 5 year of age were approached by non-probability purposive sampling. Data was analysed by using Statistical Package of Social Sciences. There were around 59.09% (n=156) and 64.43% (n=165) parents who have correctly responded regarding the number of essential immunization visit during the first and second year of their child life respectively. About 28.12% (n=108) parents responded that they do not know about the name and number of missed doses of vaccines. 31.78% (n=122) parents responded that their children have missed either one or more than one doses of routine immunization vaccines. Of which 34.42% (n=42) children have missed more than one vaccine. Lack of knowledge regarding immunization schedule 28.68% (n=34), concern about vaccine side effects 21.31%, (n=26), child sickness 17.21% (n=21), and lack of trust about government 10.65%, (n=13) were the major barriers identified by parents for missed immunization opportunities. Parents have inadequate knowledge regarding routine immunization visits, immunization schedule and vaccine doses. The practices of parents for routine childhood immunization are also poor. Parents refuse to immunize their child because of lack of immunization visit knowledge and also because of their doubts regarding vaccine potency and side effects. A proper system of immunization promotion, advocacy and reminder systems with proper follow-up mechanism need to be developed by all healthcare centres.

The Burden of Non-Communicable Disease in Transition Communities in an Asian Megacity: Baseline Findings from a Cohort Study in Karachi, Pakistan

PubMed Central

Khan, Faisal S.; Lotia-Farrukh, Ismat; Khan, Aamir J.; Siddiqui, Saad Tariq; Sajun, Sana Zehra; Malik, Amyn Abdul; Burfat, Aziza; Arshad, Mohammad Hussham; Codlin, Andrew J.; Reininger, Belinda M.; McCormick, Joseph B.; Afridi, Nadeem; Fisher-Hoch, Susan P.

2013-01-01

Background The demographic transition in South Asia coupled with unplanned urbanization and lifestyle changes are increasing the burden of non-communicable disease (NCD) where infectious diseases are still highly prevalent. The true magnitude and impact of this double burden of disease, although predicted to be immense, is largely unknown due to the absence of recent, population-based longitudinal data. The present study was designed as a unique ‘Framingham-like’ Pakistan cohort with the objective of measuring the prevalence and risk factors for hypertension, obesity, diabetes, coronary artery disease and hepatitis B and C infection in a multi-ethnic, middle to low income population of Karachi, Pakistan. Methods We selected two administrative areas from a private charitable hospital’s catchment population for enrolment of a random selection of cohort households in Karachi, Pakistan. A baseline survey measured the prevalence and risk factors for hypertension, obesity, diabetes, coronary artery disease and hepatitis B and C infection. Results Six hundred and sixty-seven households were enrolled between March 2010 and August 2011. A majority of households lived in permanent structures (85%) with access to basic utilities (77%) and sanitation facilities (98%) but limited access to clean drinking water (68%). Households had high ownership of communication technologies in the form of cable television (69%) and mobile phones (83%). Risk factors for NCD, such as tobacco use (45%), overweight (20%), abdominal obesity (53%), hypertension (18%), diabetes (8%) and pre-diabetes (40%) were high. At the same time, infectious diseases such as hepatitis B (24%) and hepatitis C (8%) were prevalent in this population. Conclusion Our findings highlight the need to monitor risk factors and disease trends through longitudinal research in high-burden transition communities in the context of rapid urbanization and changing lifestyles. They also demonstrate the urgency of public health intervention programs tailored for these transition communities. PMID:23418493

Atmospheric Pollution and Greenhouse Emissions over 14 Largest Megacities of the World

NASA Astrophysics Data System (ADS)

Chen, X.; Singh, R. P.

2017-12-01

Megacities have more than 10 million people, some of them are located in developing/developed countries. We have considered the top 14 megacities of the world. Due to growing industries, urbanization, vehicular density, and energy demand, greenhouse gas emissions have increased, which has degraded air quality. In some countries, clean air act has improved the air quality. We have considered multiple satellites and have retrieved atmospheric pollution parameters (aerosol optical depth-AOD and angstrom exponent) and greenhouse gases to study their variability from the period 2002-2016. High AOD represents high pollution level, which are prominent during winter and spring for Manila, Tokyo, Beijing, Moscow, Mexico City, Mumbai, Seoul, Dhaka, Cairo, and Bangkok. During summer and fall, Delhi, Karachi, and Sao Paulo have high values. During spring season, some of the megacities show significant higher pollution levels (high AOD) associated with the dust storms; however, Moscow and Karachi show contrasting behaviors. The angstrom exponent parameter has high values in the spring and summer for Manila, Shanghai, Beijing, Moscow, Sao Paulo, Mexico City, Seoul, and Cairo. Moscow shows a significant low value in April 2012. Delhi, Karachi, Mumbai, Dhaka, and Bangkok have high values in fall and winter. Dhaka shows significant low values in August 2003, June 2005, June 2008, July 2011, and June 2016. The total ozone column concentrations have high values during summer and spring, and low values during fall and winter. The methane concentrations are higher during fall and winter, and lower during spring and summer. An increasing trend of methane level is observed over all the megacities from 2002 until now. The increasing greenhouse gases in megacities have direct impact on human health and weather conditions. Some of the megacities suffer from dense haze, fog and smog, which impact the day-to-day lives of residents due to increasing concentrations of greenhouse gases.

New Insights into the Source of the Makran Tsunami of 27 November 1945 from Tsunami Waveforms and Coastal Deformation Data

NASA Astrophysics Data System (ADS)

Heidarzadeh, Mohammad; Satake, Kenji

2015-03-01

We constrain the source of the 27 November 1945 tsunami in the Makran Subduction Zone (MSZ) using available tsunami waveforms recorded on tide gauges at Mumbai (India) and Karachi (Pakistan), and that inferred at Port Victoria (Seychelles), and coseismic deformation data along the Makran coast. Spectral analysis of the tsunami waveforms shows that the tsunami governing period was 40-50 min at Karachi whereas it was around 22 min at Mumbai. The inferred tsunami waveform at Port Victoria also indicated a period of around 21 min for the tsunami. Tsunami numerical simulations from the previously proposed source models failed in reproducing the observed tsunami waveforms and coseismic deformation data. Sensitivity analysis showed that the source fault needs to be extended offshore into deep water in order to reproduce the first 22-min signal at Mumbai. Based on the inversion of the observed tsunami waveforms, we propose a four-segment fault with varying slip amounts as the final source. This source includes a slip of 4.3 m onshore near Ormara (Pakistan) and a slip of 10 m offshore at water depth of around 3,000 m. The total fault length is 220 km, and the average slip is 6.1 m. This source, first, reproduces fairly well the observed tide gauge records at Mumbai and Karachi, second, produces ~1 m of uplift at Ormara and ~1 m of subsidence at Pasni, and third, gives a moment magnitude of 8.3 for the earthquake, which is in the acceptable range of seismic data. The computed 1 m uplift at Ormara is in the uplift range of 1-3 m reported in the literature. As the tide gauge stations were located in the far field, our proposed source explains mainly the tectonic source of the tsunami.

Influence of an Enforcement Campaign on Seat-Belt and Helmet Wearing, Karachi-Hala Highway, Pakistan

PubMed Central

Bhatti, Junaid A.; Ejaz, Kiran; Razzak, Junaid A.; Tunio, Israr Ali; Sodhar, Irshad

2011-01-01

This study assessed to what extent an enforcement campaign influenced seat-belt and helmet wearing on a Pakistani highway. The study setting was the Karachi-Hala highway where a traffic enforcement campaign was conducted from Dec 2009 to Feb 2010. Seat-belt and helmet wearing were observed in Nov 2009 and Apr 2010 at Karachi toll plaza. Differences in wearing rates as a function of occupants’ age, sex, and vehicle type were compared between the two periods. On average, 9 119 (Standard deviation=1 896) traffic citations were issued per month from Aug 2009 to Feb 2010; 4.2% of which were for not wearing helmet. A 22.5% increase in citations was observed for Dec 2009 to Feb 2010 periods compared with Aug 2009 to Oct 2009 periods. Nearly six thousand four-wheeled and four hundred two-wheeled motorized vehicle occupants were observed in Nov 2009 and Apr 2010. Overall, two of the five drivers and one of the five front seat occupants wore seat belts. This proportion was significantly higher in drivers and front-seat occupants of cars than those of heavier vehicles. Similarly, one of two motorcyclists used a helmet but this proportion was 5.8% for pillion riders in Nov 2009. The increased enforcement had a limited influence on belt wearing in drivers (+4.0%; 95% Confidence Interval [95%CI]=1.8–6.1) and occupants (+6.2%; 95%CI=4.2–8.2). A higher increase was observed for motorcyclists (+9.8%; 95%CI=2.6–16.8) and pillion riders (+12.8%; 95%CI=5.4, 20.5). These results suggested that serious efforts are required to increase seat-belt and helmet use on Pakistani highways. Improving enforcement resources, increased fines, not allowing such vehicles on roads, and awareness campaigns targeting drivers of heavy vehicles might increase wearing rates in Pakistan. PMID:22105384