LIVIVO - Search results -

Search results

Result 1 - 10 of total 53

Search options

Article ; Online: Dynamics of camel and human hemoglobin revealed by molecular simulations

Amanat Ali / Soja Saghar Soman / Ranjit Vijayan

Scientific Reports, Vol 12, Iss 1, Pp 1-

2022 Volume 14

Abstract: Abstract Hemoglobin is one of the most widely studied proteins genetically, biochemically, and structurally. It is an oxygen carrying tetrameric protein that imparts the characteristic red color to blood. Each chain of hemoglobin harbors a heme group ... ...

Abstract	Abstract Hemoglobin is one of the most widely studied proteins genetically, biochemically, and structurally. It is an oxygen carrying tetrameric protein that imparts the characteristic red color to blood. Each chain of hemoglobin harbors a heme group embedded in a hydrophobic pocket. Several studies have investigated structural variations present in mammalian hemoglobin and their functional implications. However, camel hemoglobin has not been thoroughly explored, especially from a structural perspective. Importantly, very little is known about how the heme group interacts with hemoglobin under varying conditions of osmolarity and temperature. Several experimental studies have indicated that the tense (T) state is more stable than the relaxed (R) state of hemoglobin under normal physiological conditions. Despite the fact that R state is less stable than the T state, no extensive structural dynamics studies have been performed to investigate global quaternary transitions of R state hemoglobin under normal physiological conditions. To evaluate this, several 500 ns all-atom molecular dynamics simulations were performed to get a deeper understanding of how camel hemoglobin behaves under stress, which it is normally exposed to, when compared to human hemoglobin. Notably, camel hemoglobin was more stable under physiological stress when compared to human hemoglobin. Additionally, when compared to camel hemoglobin, cofactor-binding regions of hemoglobin also exhibited more fluctuations in human hemoglobin under the conditions studied. Several differences were observed between the residues of camel and human hemoglobin that interacted with heme. Importantly, distal residues His58 of α hemoglobin and His63 of β hemoglobin formed more sustained interactions, especially at higher temperatures, in camel hemoglobin. These residues are important for oxygen binding to hemoglobin. Thus, this work provides insights into how camel and human hemoglobin differ in their interactions under stress.
Keywords	Medicine ; R ; Science ; Q
Subject code	612
Language	English
Publishing date	2022-01-01T00:00:00Z
Publisher	Nature Portfolio
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

Full text online

Full text

Inter-library loan at ZB MED

Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

Article ; Online: Dynamics of the ACE2–SARS-CoV-2/SARS-CoV spike protein interface reveal unique mechanisms

Amanat Ali / Ranjit Vijayan

Scientific Reports, Vol 10, Iss 1, Pp 1-

2020 Volume 12

Abstract: Abstract The coronavirus disease 2019 (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a major public health concern. A handful of static structures now provide molecular insights into how SARS-CoV-2 and ...

Abstract	Abstract The coronavirus disease 2019 (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a major public health concern. A handful of static structures now provide molecular insights into how SARS-CoV-2 and SARS-CoV interact with its host target, which is the angiotensin converting enzyme 2 (ACE2). Molecular recognition, binding and function are dynamic processes. To evaluate this, multiple 500 ns or 1 μs all-atom molecular dynamics simulations were performed to better understand the structural stability and interfacial interactions between the receptor binding domain of the spike (S) protein of SARS-CoV-2 and SARS-CoV bound to ACE2. Several contacts were observed to form, break and reform in the interface during the simulations. Our results indicate that SARS-CoV-2 and SARS-CoV utilizes unique strategies to achieve stable binding to ACE2. Several differences were observed between the residues of SARS-CoV-2 and SARS-CoV that consistently interacted with ACE2. Notably, a stable salt bridge between Lys417 of SARS-CoV-2 S protein and Asp30 of ACE2 as well as three stable hydrogen bonds between Tyr449, Gln493 and Gln498 of SARS-CoV-2 and Asp38, Glu35 and Lys353 of ACE2 were observed, which were absent in the ACE2–SARS-CoV interface. Some previously reported residues, which were suggested to enhance the binding affinity of SARS-CoV-2, were not observed to form stable interactions in these simulations. Molecular mechanics-generalized Born surface area based free energy of binding was observed to be higher for SARS-CoV-2 in all simulations. Stable binding to the host receptor is crucial for virus entry. Therefore, special consideration should be given to these stable interactions while designing potential drugs and treatment modalities to target or disrupt this interface.
Keywords	Medicine ; R ; Science ; Q ; covid19
Language	English
Publishing date	2020-08-01T00:00:00Z
Publisher	Nature Publishing Group
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

Full text online

Full text

Inter-library loan at ZB MED

Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

Article ; Online: The Impact of Foreign Aid on Income Inequality

Misbah Nosheen / Sundas Maqbool / Syed Hila Mubarak / Amanat Ali

NUST Journal of Social Sciences and Humanities, Vol 7, Iss

Evidence from Developing Countries. Application of the FMOLS Approach

2022 Volume 2

Abstract: The present study aims to evaluate the impact of foreign assistance on income inequality of selected developing economies. Panel co-integration technique is applied for the purpose of estimation. After confirming the pre-conditions for cointegration, we ... ...

Abstract	The present study aims to evaluate the impact of foreign assistance on income inequality of selected developing economies. Panel co-integration technique is applied for the purpose of estimation. After confirming the pre-conditions for cointegration, we have applied the Fully Modified-OLS method to estimate the association between foreign aid and income inequality. Controlling for other variables, we find a positive and significant association between foreign aid and inequality. The empirical results are robust concerning the sub-samples of developing economies selected according to the income classification of the World Bank. The empirical results are also robust concerning the alternative measure of income inequality.
Keywords	Foreign Aid ; Inequality ; Gini Index ; Pedroni Test ; Social Sciences ; H
Language	English
Publishing date	2022-07-01T00:00:00Z
Publisher	National University of Sciences and Technology
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

Full text online

Full text

Inter-library loan at ZB MED

Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

Article ; Online: Interaction of Glutathione with MMACHC Arginine-Rich Pocket Variants Associated with Cobalamin C Disease

Priya Antony / Bincy Baby / Amanat Ali / Ranjit Vijayan / Fatma Al Jasmi

Biomedicines, Vol 11, Iss 12, p

Insights from Molecular Modeling

2023 Volume 3217

Abstract: Methylmalonic aciduria and homocystinuria type C protein (MMACHC) is required by the body to metabolize cobalamin (Cbl). Due to its complex structure and cofactor forms, Cbl passes through an extensive series of absorptive and processing steps before ... ...

Abstract	Methylmalonic aciduria and homocystinuria type C protein (MMACHC) is required by the body to metabolize cobalamin (Cbl). Due to its complex structure and cofactor forms, Cbl passes through an extensive series of absorptive and processing steps before being delivered to mitochondrial methyl malonyl-CoA mutase and cytosolic methionine synthase. Depending on the cofactor attached, MMACHC performs either flavin-dependent reductive decyanation or glutathione (GSH)-dependent dealkylation. The alkyl groups of Cbl have to be removed in the presence of GSH to produce intermediates that can later be converted into active cofactor forms. Pathogenic mutations in the GSH binding site, such as R161Q, R161G, R206P, R206W, and R206Q, have been reported to cause Cbl diseases. The impact of these variations on MMACHC’s structure and how it affects GSH and Cbl binding at the molecular level is poorly understood. To better understand the molecular basis of this interaction, mutant structures involving the MMACHC-MeCbl-GSH complex were generated using in silico site-directed point mutations and explored using molecular dynamics (MD) simulations. The results revealed that mutations in the key arginine residues disrupt GSH binding by breaking the interactions and reducing the free energy of binding of GSH. Specifically, variations at position 206 appeared to produce weaker GSH binding. The lowered binding affinity for GSH in the variant structures could impact metabolic pathways involving Cbl and its trafficking.
Keywords	glutathione ; methylcobalamin ; arginine-rich pocket ; docking ; molecular dynamics ; Biology (General) ; QH301-705.5
Subject code	570
Language	English
Publishing date	2023-12-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

Full text online

Full text

Inter-library loan at ZB MED

Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

Article ; Online: The Impact of Foreign Aid on Income Inequality

Misbah Nosheen / Sundas Maqbool / Syed Hila Mubarak / Amanat Ali

NUST Journal of Social Sciences and Humanities, Vol 7, Iss

Evidence from Developing Countries. Application of the FMOLS Approach

2022 Volume 2

Abstract	The present study aims to evaluate the impact of foreign assistance on income inequality of selected developing economies. Panel co-integration technique is applied for the purpose of estimation. After confirming the pre-conditions for cointegration, we have applied the Fully Modified-OLS method to estimate the association between foreign aid and income inequality. Controlling for other variables, we find a positive and significant association between foreign aid and inequality. The empirical results are robust concerning the sub-samples of developing economies selected according to the income classification of the World Bank. The empirical results are also robust concerning the alternative measure of income inequality.
Keywords	Foreign Aid ; Inequality ; Gini Index ; Pedroni Test ; Social Sciences ; H
Language	English
Publishing date	2022-07-01T00:00:00Z
Publisher	National University of Sciences and Technology
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

Full text online

Full text

Inter-library loan at ZB MED

Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

Article ; Online: Strategic Flexibility and Organizational Performance

Muhammad Awais / Amanat Ali / Muhammad Sajid Khattak / Muhammad Irfanullah Arfeen / Muhammad Azam I. Chaudhary / Aleena Syed

SAGE Open, Vol

Mediating Role of Innovation

2023 Volume 13

Abstract: Strategic flexibility is deemed to be an important organizational capability for enhancing innovation and improving organizational performance (OP) in uncertain, turbulent, and ever-changing business environments. Many studies have investigated the ... ...

Abstract	Strategic flexibility is deemed to be an important organizational capability for enhancing innovation and improving organizational performance (OP) in uncertain, turbulent, and ever-changing business environments. Many studies have investigated the impact of strategic flexibility on innovation and OP in various contexts and found that strategic flexibility enhances innovation and improves OP. Other studies have found negative association or no association between strategic flexibility and OP. Therefore, it is not much clear whether strategic flexibility improves OP directly or through innovation. Especially, the mediating role of innovation in the association between strategic flexibility and OP in engineering project-based organizations has not been fully grabbed in prior literature and Pakistan remained unexplored. This study has strived to examine the mediating role of innovation in the association between strategic flexibility and OP in this context. Drawing upon resource based and dynamic capability views, an explanatory model was developed and tested by applying PLS-SEM higher order component modeling approach using sample data from 184 organizations in Pakistan. The results revealed that strategic flexibility is positively associated with innovation and OP. Innovation is positively associated with OP. The association between strategic flexibility and OP is partially mediated by innovation. The study promotes academic rigor and provides a new theoretical model. Mangers, decision-makers, and policy-makers can utilize the results to update their plans to achieve sustainable OP. The other organizations in various countries operating under similar conditions can also take the advantage of this study.
Keywords	History of scholarship and learning. The humanities ; AZ20-999 ; Social Sciences ; H
Subject code	650
Language	English
Publishing date	2023-06-01T00:00:00Z
Publisher	SAGE Publishing
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

Full text online

Full text

Inter-library loan at ZB MED

Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

Article ; Online: Characterization of ACE2 naturally occurring missense variants

Sally Badawi / Feda E. Mohamed / Nesreen R. Alkhofash / Anne John / Amanat Ali / Bassam R. Ali

Human Genomics, Vol 16, Iss 1, Pp 1-

impact on subcellular localization and trafficking

2022 Volume 16

Abstract: Abstract Background Human angiotensin-converting enzyme 2 (ACE2), a type I transmembrane receptor physiologically acting as a carboxypeptidase enzyme within the renin-angiotensin system (RAS), is a critical mediator of infection by several severe acute ... ...

Abstract	Abstract Background Human angiotensin-converting enzyme 2 (ACE2), a type I transmembrane receptor physiologically acting as a carboxypeptidase enzyme within the renin-angiotensin system (RAS), is a critical mediator of infection by several severe acute respiratory syndrome (SARS) corona viruses. For instance, it has been demonstrated that ACE2 is the primary receptor for the SARS-CoV-2 entry to many human cells through binding to the viral spike S protein. Consequently, genetic variability in ACE2 gene has been suggested to contribute to the variable clinical manifestations in COVID-19. Many of those genetic variations result in missense variants within the amino acid sequence of ACE2. The potential effects of those variations on binding to the spike protein have been speculated and, in some cases, demonstrated experimentally. However, their effects on ACE2 protein folding, trafficking and subcellular targeting have not been established. Results In this study we aimed to examine the potential effects of 28 missense variants (V801G, D785N, R768W, I753T, L731F, L731I, I727V, N720D, R710H, R708W, S692P, E668K, V658I, N638S, A627V, F592L, G575V, A501T, I468V, M383I, G173S, N159S, N149S, D38E, N33D, K26R, I21T, and S19P) distributed across the ACE2 receptor domains on its subcellular trafficking and targeting through combinatorial approach involving in silico analysis and experimental subcellular localization analysis. Our data show that none of the studied missense variants (including 3 variants predicted to be deleterious R768W, G575V, and G173S) has a significant effect on ACE2 intracellular trafficking and subcellular targeting to the plasma membrane. Conclusion Although the selected missense variants display no significant change in ACE2 trafficking and subcellular localization, this does not rule out their effect on viral susceptibility and severity. Further studies are required to investigate the effect of ACE2 variants on its expression, binding, and internalization which might explain the variable clinical ...
Keywords	Angiotensin-converting enzyme 2 (ACE2) ; Subcellular trafficking ; SARS-CoV-2 ; Polymorphism ; Medicine ; R ; Genetics ; QH426-470
Subject code	612
Language	English
Publishing date	2022-09-01T00:00:00Z
Publisher	BMC
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

Full text online

Full text

Inter-library loan at ZB MED

Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

Article ; Online: Molecular insights into the interaction of hemorphin and its targets

Amanat Ali / Bincy Baby / Soja Saghar Soman / Ranjit Vijayan

Scientific Reports, Vol 9, Iss 1, Pp 1-

2019 Volume 16

Abstract: Abstract Hemorphins are atypical endogenous opioid peptides produced by the cleavage of hemoglobin beta chain. Several studies have reported the therapeutic potential of hemorphin in memory enhancement, blood regulation, and analgesia. However, the mode ... ...

Abstract	Abstract Hemorphins are atypical endogenous opioid peptides produced by the cleavage of hemoglobin beta chain. Several studies have reported the therapeutic potential of hemorphin in memory enhancement, blood regulation, and analgesia. However, the mode of interaction of hemorphin with its target remains largely elusive. The decapeptide LVV-hemorphin-7 is the most stable form of hemorphin. It binds with high affinity to mu-opioid receptors (MOR), angiotensin-converting enzyme (ACE) and insulin-regulated aminopeptidase (IRAP). In this study, computational methods were used extensively to elucidate the most likely binding pose of mammalian LVV-hemorphin-7 with the aforementioned proteins and to calculate the binding affinity. Additionally, alignment of mammalian hemorphin sequences showed that the hemorphin sequence of the camel harbors a variation – a Q > R substitution at position 8. This study also investigated the binding affinity and the interaction mechanism of camel LVV-hemorphin-7 with these proteins. To gain a better understanding of the dynamics of the molecular interactions between the selected targets and hemorphin peptides, 100 ns molecular dynamics simulations of the best-ranked poses were performed. Simulations highlighted major interactions between the peptides and key residues in the binding site of the proteins. Interestingly, camel hemorphin had a higher binding affinity and showed more interactions with all three proteins when compared to the canonical mammalian LVV-hemorphin-7. Thus, camel LVV-hemorphin-7 could be explored as a potent therapeutic agent for memory loss, hypertension, and analgesia.
Keywords	Medicine ; R ; Science ; Q
Subject code	540
Language	English
Publishing date	2019-10-01T00:00:00Z
Publisher	Nature Publishing Group
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

Full text online

Full text

Inter-library loan at ZB MED

Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

Article ; Online: RESULTS OF IRRIGATION OF MAXILLARY SINUS WITH METRONIDAZOLE AFTER ANTRAL WASHOUT IN PATIENTS WITH CHRONIC MAXILLARY SINUSITIS

Amir Ali Khan / Amanat Ali Shah / Tehmina Rehman / Abdullah .

Pakistan Armed Forces Medical Journal, Vol 68, Iss 2, Pp 241-

2018 Volume 244

Abstract: Objective: To compare the results of antral washout with and without metronidazole irrigation of maxillary sinus in patients with chronic maxillary sinusitis. Study Design: Quasi experimental study. Place and Duration of Study: This Quasi experimental ... ...

Abstract	Objective: To compare the results of antral washout with and without metronidazole irrigation of maxillary sinus in patients with chronic maxillary sinusitis. Study Design: Quasi experimental study. Place and Duration of Study: This Quasi experimental study was carried out in Combined Military Hospital Khuzdar and Combined Military Hospital Attock, from Mar 2013 to Apr 2015. Patient and Method: One hundred patients who were between 20-50 years of age were included in this study.Half of them received antral irrigation of metronidazole in addition to postoperative oral antibiotics were compared with the other half who received just oral antibiotics after antral washout procedure. Clinical success was compared in both groups in terms of patients becoming asymptomatic. Results: Clinical success in both groups at the end of the study was 94% and 80% of patients with antral irrigation of metronidazole and without it respectively showing that metronidazole irrigation is superior method. Conclusion: Antral irrigation with metronidazole after antral washout procedure in patient with chronic maxillary sinusitis is very effective in early recovery from the disease. Keywords: Metronidazole, Rhinorrhea, Sinusitis.
Keywords	metronidazole ; rhinorrhea ; Medicine ; R ; Medicine (General) ; R5-920
Language	English
Publishing date	2018-04-01T00:00:00Z
Publisher	Army Medical College Rawalpindi
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

Full text online

Full text

Inter-library loan at ZB MED

Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

Article ; Online: Does Governance in Information Technology Matter When It Comes to Organizational Performance in Pakistani Public Sector Organizations? Mediating Effect of Innovation

Amanat Ali / Shahid Iqbal / Syed Arslan Haider / Shehnaz Tehseen / Bilal Anwar / Mariam Sohail / Khalid Rehman

SAGE Open, Vol

2021 Volume 11

Abstract: Information technology governance (ITG) is recognized as a vital organizational ability to exploit opportunities for innovation and enhance organizational performance. However, the potential of ITG for public sector innovation and performance has not ... ...

Abstract	Information technology governance (ITG) is recognized as a vital organizational ability to exploit opportunities for innovation and enhance organizational performance. However, the potential of ITG for public sector innovation and performance has not been fully grasped in Pakistani public sector organizations (PakPSOs). This study has presented an explanatory model to investigate the mediating effect of innovation in the relationship between ITG and organizational performance in PakPSOs. Partial least squares structural equation modeling (PLS-SEM)–based hierarchical component modeling approach has applied to analyze the model by taking sample data from 97 PakPSOs. The results revealed that ITG positively affected innovation and organizational performance. Innovation positively affected organizational performance. Innovation partially mediated the relationship between ITG and organizational performance. The study corroborates the strategic use of information technology (IT) to enhance innovation and organizational performance in this context. The study contributes to the existing knowledge base through a new theoretical model and promotes academic rigor. The results are also significant for the practice as they can help to achieve organizational performance in terms of operational efficiency, transparency in costs and results, planning and decision making, performance monitoring and control, and collaboration and synergy. The other countries operating in a similar environment can also take the benefit of this study.
Keywords	History of scholarship and learning. The humanities ; AZ20-999 ; Social Sciences ; H
Subject code	650
Language	English
Publishing date	2021-05-01T00:00:00Z
Publisher	SAGE Publishing
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

Full text online

Full text

Inter-library loan at ZB MED

Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

To top

Full text online

More links

Kategorien

Inter-library loan at ZB MED

Full text online

More links

Kategorien

Inter-library loan at ZB MED

Full text online

More links

Kategorien

Inter-library loan at ZB MED

Full text online

More links

Kategorien

Inter-library loan at ZB MED

Full text online

More links

Kategorien

Inter-library loan at ZB MED

Full text online

More links

Kategorien

Inter-library loan at ZB MED

Full text online

More links

Kategorien

Inter-library loan at ZB MED

Full text online

More links

Kategorien

Inter-library loan at ZB MED

Full text online

More links

Kategorien

Inter-library loan at ZB MED

Full text online

More links

Kategorien

Inter-library loan at ZB MED