Hoda Mohammed - Academia.edu (original) (raw)
Papers by Hoda Mohammed
Journal of Pharmacy and Pharmacology, 2004
Selective cardiotoxicity of doxorubicin (DOX) remains a significant and dose-limiting clinical pr... more Selective cardiotoxicity of doxorubicin (DOX) remains a significant and dose-limiting clinical problem. The mechanisms implicated are not yet fully defined but may involve the production of reactive oxygen species or expression of cytokines. Although patients with advanced congestive heart failure express elevated circulating levels of tumour necrosis factor-(TNF), little is known about the prognostic importance and regulation of TNF in the heart in cardiac disease states. Here we tested whether the expression of TNF, along with oxidative stress, is associated with the development of DOX-induced cardiomyopathy (DOX-CM) and whether concurrent treatment with taurine (Taur), an antioxidant, or rolipram (Rolp), a TNF inhibitor, offer a certain protection against DOX cardiotoxic properties. DOX (cumulative dose, 12 mg kg À1 ) was administered to rats in six equal (intraperitoneal) injections over a period of 6 weeks. Cardiomyopathy was evident by myocardial cell damage, which was characterized by a dense indented nucleus with peripheral heterochromatin condensation and distorted mitochondria, as well as significant increase in serum levels of creatine kinase and lactate dehydrogenase. DOX also induced an increment (P < 0.001) in serum TNF and plasma nitric oxide levels. The extent of left ventricular (LV) superoxide anion, lipid peroxide measured as malondialdehyde, catalase and calcium content were markedly elevated, whereas superoxide dismutase, total and non-protein-bound thiol were dramatically decreased in DOX-treated rats. Exaggeration of DOX-CM was achieved by intraperitoneal injection of lipopolysaccharide (LPS) (1 mg kg À1 ) 18h before sampling and evaluated by highly significant increase in heart enzymes (P < 0.001), oxidative stress biomarkers and TNF production. Pre-and co-treatment of DOX or DOX-LPS rats with Taur (1% daily supplemented in drinking water, 10 days before and concurrent with DOX) or Rolp (3 mg kg À1 , intraperitoneally, one dose before DOX administration then every 2 weeks throughout the experimental period) ameliorated the deleterious effect of both DOX and LPS on the aforementioned parameters. Meanwhile, it is noteworthy that Rolp exhibited a more preferable effect on serum TNF level. Taur and rolipram also restored the myocardial apoptosis induced by DOX. In conclusion, a cumulative dose of DOX affected free radical and TNF production in the heart of an experimental cardiomyopathy animal model. The current results suggest that down-regulation of these radicals and cytokines could be maintained by using the free radical scavenger Taur or, more favourably, the TNF inhibitor Rolp.
Pharmacological Research, 2000
Adriamycin (ADR) is a potent antitumor antibiotic drug known to cause severe cardiac toxicity. Al... more Adriamycin (ADR) is a potent antitumor antibiotic drug known to cause severe cardiac toxicity. Although ADR generates free radicals, the role of these radicals in the development of cardiac toxicity is still not well understood. In the present study, we evaluated the effect of glutathione (GSH) supplementation or depletion on ADR-induced cardiotoxicity in male Wistar rats. Cardiac toxicity was induced by a single intraperitoneal injection of ADR (20 mg kg −1 ) and manifested by an increase in heart rate, blood pressure elevation, and increased serum creatine kinase (CK) and lactate dehydrogenase (LDH). The extent of lipoprotein oxidation, lipid peroxide measured as malondialdhye (MDA), total homocysteine (tHcy), lipid profile, and atherogenic index were markedly elevated, whereas cardiac GSH content was dramatically decreased in ADR rats. Pre-and co-treatment of ADR rats with GSH (5 mM kg −1 ) (ADR+GSH) markedly reduced the levels of CK, LDH, lipoprotein oxidation susceptibility, cardiac MDA, tHcy and atherogenic index, and elevated GSH levels in cardiac tissues. In contrast, GSH depletion through administration of Lbuthionine-(S,R)-sulfoximine (BSO) (15 mM kg −1 ) before and after ADR injection (ADR+BSO) greatly exacerbated ADR cardiotoxicity compared to the control and ADR groups. Finally, there were also severe cardiac histopathological changes in ADR and ADR+BSO groups, which were nearly restored by GSH treatment. These results suggest that GSH inhibits ADR cardiotoxicity and might serve as a novel combination with ADR to limit free radical-mediated organ injury.
The purpose of this ongoing work is to investigate and improve access to digital assets at the No... more The purpose of this ongoing work is to investigate and improve access to digital assets at the Norwegian National Library using mobile phones. The project is thus part of a growing effort towards transliteracy which is the ability to read, to write and otherwise communicate and interact across a range of platforms, tools and media. The National Library's website at www.nb.no plays an essential role in Norway's online library services. For development purposes an alternative mobile access point is created. This site provides tests of variant push and pulls modes, present "elite editions" and test polyvalent organization of selected materials. A National Library Mobile User Network is described as are two practical case studies.
The functionality of the wireless application protocol (WAP) dependent nomadic devices can be enh... more The functionality of the wireless application protocol (WAP) dependent nomadic devices can be enhanced using techniques for the reconfiguration of such devices in the mobile environment, either individually or en mass. For example, a system that enables the hand-held devices of selected personnel at a disaster site to be automatically adapted for specifically directed emergency WAP communications is highly beneficial. In this paper we present a method for the provision of configuration settings over the wireless application protocol using the GSM short messages system (SMS). Discussion of implementation of wireless datagram protocol, wireless session protocol and wireless application environment layers is included. Data for push operation via an SMS gateway is presented that demonstrates increasing popularity amongst users.
Talks by Hoda Mohammed
Journal of Pharmacy and Pharmacology, 2004
Selective cardiotoxicity of doxorubicin (DOX) remains a significant and dose-limiting clinical pr... more Selective cardiotoxicity of doxorubicin (DOX) remains a significant and dose-limiting clinical problem. The mechanisms implicated are not yet fully defined but may involve the production of reactive oxygen species or expression of cytokines. Although patients with advanced congestive heart failure express elevated circulating levels of tumour necrosis factor-(TNF), little is known about the prognostic importance and regulation of TNF in the heart in cardiac disease states. Here we tested whether the expression of TNF, along with oxidative stress, is associated with the development of DOX-induced cardiomyopathy (DOX-CM) and whether concurrent treatment with taurine (Taur), an antioxidant, or rolipram (Rolp), a TNF inhibitor, offer a certain protection against DOX cardiotoxic properties. DOX (cumulative dose, 12 mg kg À1 ) was administered to rats in six equal (intraperitoneal) injections over a period of 6 weeks. Cardiomyopathy was evident by myocardial cell damage, which was characterized by a dense indented nucleus with peripheral heterochromatin condensation and distorted mitochondria, as well as significant increase in serum levels of creatine kinase and lactate dehydrogenase. DOX also induced an increment (P < 0.001) in serum TNF and plasma nitric oxide levels. The extent of left ventricular (LV) superoxide anion, lipid peroxide measured as malondialdehyde, catalase and calcium content were markedly elevated, whereas superoxide dismutase, total and non-protein-bound thiol were dramatically decreased in DOX-treated rats. Exaggeration of DOX-CM was achieved by intraperitoneal injection of lipopolysaccharide (LPS) (1 mg kg À1 ) 18h before sampling and evaluated by highly significant increase in heart enzymes (P < 0.001), oxidative stress biomarkers and TNF production. Pre-and co-treatment of DOX or DOX-LPS rats with Taur (1% daily supplemented in drinking water, 10 days before and concurrent with DOX) or Rolp (3 mg kg À1 , intraperitoneally, one dose before DOX administration then every 2 weeks throughout the experimental period) ameliorated the deleterious effect of both DOX and LPS on the aforementioned parameters. Meanwhile, it is noteworthy that Rolp exhibited a more preferable effect on serum TNF level. Taur and rolipram also restored the myocardial apoptosis induced by DOX. In conclusion, a cumulative dose of DOX affected free radical and TNF production in the heart of an experimental cardiomyopathy animal model. The current results suggest that down-regulation of these radicals and cytokines could be maintained by using the free radical scavenger Taur or, more favourably, the TNF inhibitor Rolp.
Pharmacological Research, 2000
Adriamycin (ADR) is a potent antitumor antibiotic drug known to cause severe cardiac toxicity. Al... more Adriamycin (ADR) is a potent antitumor antibiotic drug known to cause severe cardiac toxicity. Although ADR generates free radicals, the role of these radicals in the development of cardiac toxicity is still not well understood. In the present study, we evaluated the effect of glutathione (GSH) supplementation or depletion on ADR-induced cardiotoxicity in male Wistar rats. Cardiac toxicity was induced by a single intraperitoneal injection of ADR (20 mg kg −1 ) and manifested by an increase in heart rate, blood pressure elevation, and increased serum creatine kinase (CK) and lactate dehydrogenase (LDH). The extent of lipoprotein oxidation, lipid peroxide measured as malondialdhye (MDA), total homocysteine (tHcy), lipid profile, and atherogenic index were markedly elevated, whereas cardiac GSH content was dramatically decreased in ADR rats. Pre-and co-treatment of ADR rats with GSH (5 mM kg −1 ) (ADR+GSH) markedly reduced the levels of CK, LDH, lipoprotein oxidation susceptibility, cardiac MDA, tHcy and atherogenic index, and elevated GSH levels in cardiac tissues. In contrast, GSH depletion through administration of Lbuthionine-(S,R)-sulfoximine (BSO) (15 mM kg −1 ) before and after ADR injection (ADR+BSO) greatly exacerbated ADR cardiotoxicity compared to the control and ADR groups. Finally, there were also severe cardiac histopathological changes in ADR and ADR+BSO groups, which were nearly restored by GSH treatment. These results suggest that GSH inhibits ADR cardiotoxicity and might serve as a novel combination with ADR to limit free radical-mediated organ injury.
The purpose of this ongoing work is to investigate and improve access to digital assets at the No... more The purpose of this ongoing work is to investigate and improve access to digital assets at the Norwegian National Library using mobile phones. The project is thus part of a growing effort towards transliteracy which is the ability to read, to write and otherwise communicate and interact across a range of platforms, tools and media. The National Library's website at www.nb.no plays an essential role in Norway's online library services. For development purposes an alternative mobile access point is created. This site provides tests of variant push and pulls modes, present "elite editions" and test polyvalent organization of selected materials. A National Library Mobile User Network is described as are two practical case studies.
The functionality of the wireless application protocol (WAP) dependent nomadic devices can be enh... more The functionality of the wireless application protocol (WAP) dependent nomadic devices can be enhanced using techniques for the reconfiguration of such devices in the mobile environment, either individually or en mass. For example, a system that enables the hand-held devices of selected personnel at a disaster site to be automatically adapted for specifically directed emergency WAP communications is highly beneficial. In this paper we present a method for the provision of configuration settings over the wireless application protocol using the GSM short messages system (SMS). Discussion of implementation of wireless datagram protocol, wireless session protocol and wireless application environment layers is included. Data for push operation via an SMS gateway is presented that demonstrates increasing popularity amongst users.