Mohammed khalid - Academia.edu (original) (raw)

Papers by Mohammed khalid

Iranian Journal of Child Neurology, 2013

Spontaneous ventral spinal epidural hematomas are extremely rare in children and clinically recog... more Spontaneous ventral spinal epidural hematomas are extremely rare in children and clinically recognized by the appearance of acute asymmetric focal motor and sensory involvement. In infants, the initial presenting symptoms are very non-specific and irritability is often the only initial manifestation. Appearance of other neurological signs may be delayed up to hours or even days later. In the absence of significant precipitating factors such as severe trauma or previously known coagulopathies, the diagnosis is usually delayed until the full picture of severe cord compression is developed. The diagnosis is finally made by performing magnetic resonance imaging. We report a 5-month-old infant with spinal epidural hematoma who presented with symmetrical upper limb weakness and diaphragmatic involvement to highlight the importance of recognizing the atypical manifestations for early diagnosis and intervention.

Word Counts: Abstract = 165 words Text= 53,461 characters (with spaces) ABSTRACT 23 24 The HIV-1 ... more Word Counts: Abstract = 165 words Text= 53,461 characters (with spaces) ABSTRACT 23 24 The HIV-1 Vpu accessory protein is a transmembrane protein that downregulates CD4 25 expression and promotes the release of new virions. We screened a human leukocyte yeast 26 two-hybrid expression library to discover novel Vpu-interacting cellular proteins. The major 27 histocompatibility class II (MHCII) invariant chain, also called Ii or CD74, was found to be 28 one such protein. We show direct binding of Vpu and CD74 using the yeast two-hybrid assay 29 and coimmunoprecipitation from HIV-1 infected cells. The cytoplasmic region of Vpu was 30 found to interact with the 30-amino acid cytoplasmic tail of CD74. Human monocytic U937 31 cells infected with wild type or vpu-defective HIV-1, and transfected cells showed that Vpu 32 down modulated the surface expression of mature MHCII. The reduction in cell surface 33 mature MHCII correlated with decreased antigen-presentation to T cells in culture. Thus, the 34 Vpu protein also contributes to viral persistence by attenuating immune responses during 35 HIV infection. This report further exemplifies the rich diversity and redundancy shown by 36 HIV for immune evasion. 37 A C C E P T E D deficiency syndrome in pig-tailed macaques. Virology 256:54-63.

Chest Journal, Oct 1, 2012

Background: Pulmonary hypertension (PH) is associated with dilatation of main pulmonary artery on... more Background: Pulmonary hypertension (PH) is associated with dilatation of main pulmonary artery on thoracic computerized tomogram (CT). It is not clear whether the diameter of main pulmonary artery is correlated with degree of pulmonary hypertension Objective: To assess the relationship between the degrees of pulmonary artery pressure (PAP) measured by Doppler echocardiography (DE) and pulmonary artery diameter (PAD) and its ratio to ascending aorta (PA/AO) on thoracic CT scan. Methods: Forty eight patients with diagnosis of pulmonary hypertension diagnosed on Doppler echocardiography who had contrasted CT scan of chest were included in the study. The patients were grouped into mild, moderated and severe pulmonary hypertension based on the degree of pulmonary artery pressure. Diameter of main pulmonary artery on contrasted thoracic CT scan just above the bifurcation and its ratio to the diameter of ascending aorta at the same level was measured. Statistical analysis was made to determine the relationship between the degree of PAP and measurements of PAD and PA/AO ratio.

The American Journal of Tropical Medicine and Hygiene, Apr 1, 2005

A 25-year-old woman, later identified as index case of Crimean-Congo hemorrhagic fever (CCHF), pr... more A 25-year-old woman, later identified as index case of Crimean-Congo hemorrhagic fever (CCHF), presented to Holy Family Hospital in Rawalpindi, Pakistan with fever and generalized coagulopathy. A retrospective contact tracing was conducted to explore the modes of exposure possibly associated with transmission of CCHF infection among contacts. We traced 32 contacts of the index case and 158 contacts of secondary cases and tested them for IgG and IgM antibodies against CCHF virus by an enzyme-linked immunosorbent assay technique. According to the type of exposure, contacts were divided into five subsets: percutaneous contact with blood, blood contact to unbroken skin, cutaneous contact to non-sanguineous body fluids, physical contact with patients without body fluids contact, and close proximity without touching. Two out of four contacts who reported percutaneous exposure tested positive for antibodies to CCHF virus. We conclude that simple barrier methods and care in provision of CCHF cases may prevent transmission of this infection.

The anisotropic momentum distribution of photoexcited hot electrons on recombination with holes a... more The anisotropic momentum distribution of photoexcited hot electrons on recombination with holes at the acceptor level produces linearly polarized luminescence. It is found that the degree of linear polarization (DoLP) of the luminescence over the whole width of the first heavy hole peak (0HH) is not constant. Calculations within the spherical approximation show that in bulk GaAs the DoLP over the 0HH peak should vary from zero, at the low energy side, to its maximum value (0.33), at the high energy side of the 0HH peak, for the electric vector of excitation hat {e}\vert \vert [110] excitation geometry and vice versa for the hat {e}\vert \vert [100] excitation geometry. This variation in the DoLP over the 0HH peak will be referred to as the anisotropy of the DoLP and arises as a direct result of the warping of the heavy hole sub-band. Experimental results were found in qualitative agreement with the calculations under spherical approximation. The calculations within the diagonal approximation could not account for the unexpectedly high value of the DoLP towards the low energy side of the 0HH peak.

Turkish Journal of Physics, 2004

Developer composition type and development technique are known to influence surface and edge roug... more Developer composition type and development technique are known to influence surface and edge roughness in polymethylemethacrylate (PMMA); and it is during development, we believe, that the result is most influenced by the phase separation into polymer-rich and polymer-poor regions. This polymer phase separation is more prominent in a weaker developer and low temperature. In this paper, we investigate the effect of development time on the extent of polymer phase separation in an exposed PMMA developed in a standard developer i.e. 1:3 MIBK:IPA at 20 °C and rinsed in pure IPA for 30 sec. The polymer phase separation is found to increase with the development time.

Journal of Personality Assessment, 2015

International Journal of Nanoscience

Carbon nanotubes (CNTs) have been successfully synthesized by using in-house fabricated Double St... more Carbon nanotubes (CNTs) have been successfully synthesized by using in-house fabricated Double Stage Chemical Vapor Deposition (DS-CVD) technique, using acetylene (C2H2) and hydrogen (H2) as the precursor gases. The purity, morphology and the structure of CNTs were then characterized using Field Emission Scanning Microscope (FESEM), Transmission Electron Microscope (TEM) and Thermogravimetric Analysis (TGA). The effects of the process parameters were examined whereby the experimental design of the investigation was conducted using Design Expert® Version 6.0.8. The statistical analysis reveals that the optimized conditions for the best CNTs yield production at 850°C reaction temperature, 60 min reaction time, with gas flow rates at 40 and 150 ml/min for C2H2 and H2, respectively. The CNTs produced were successfully used as column chromatographic media. Due to its nanosized structured dimension, CNTs' have tremendously large surface area and that lead to highly efficient protein p...

Annals of Saudi medicine

Middle Eastern respiratory syndrome caused by novel coronavirus (MERS CoV) has been a major publi... more Middle Eastern respiratory syndrome caused by novel coronavirus (MERS CoV) has been a major public health challenge since it was first described in 2012 in Saudi Arabia. So far, there is no effective treatment for this serious illness, which features a high mortality rate. We report an initial experience of the use of ribavirin and interferon (IFN)-a2b in the management of MERS CoV at a tertiary care hospital. A case series of 6 patients admitted with a confirmed diagnosis of MERS CoV were treated with ribavirin and IFN-a2b in addition to supportive management. The patients' demographics, clinical parameters, and outcomes were recorded. Fifty-four close contacts of these patients were screened for MERS CoV. Six patients with MERS CoV infection were included in this study. Four cases featured symptomatic disease, including pneumonia and respiratory failure, while 2 were asymptomatic close contacts of the MERS CoV patients. The MERS CoV infection was confirmed by reverse transcrip...

A numerical study on heat transfer enhancement utilizing nanofluids in a two-dimensional enclosur... more A numerical study on heat transfer enhancement utilizing nanofluids in a two-dimensional enclosure was investigated for various pertinent parameters using commercial CFD code FLUENT 6.3. Numerical simulations were carried out assuming nanofluid as single phase. Effect of Rayleigh number ranging from 6 3 10 10 ≤ ≤ Ra and nanoparticle volume fraction (0-20%) was studied on flow pattern and energy transport within the thermal boundary layer for aspect ratio of 1.0. Stream function and isotherm contours were plotted for all the above mentioned parameters. Results show that effect of buoyancy parameter and volume fraction causes increase in average heat transfer enhancement. The results were also compared with the khanafer's model and found to be in good agreement.

Journal of Applied Polymer Science, 2014

Scrap rubber reclamation is one of the most desirable approaches to solve the disposal problem of... more Scrap rubber reclamation is one of the most desirable approaches to solve the disposal problem of used tires. However, reclaimed tire rubber (RTR) has not gained enough attention due to its poor properties. In this work, the effects of poly(ethylene-covinyl acetate) (EVA) addition and electron beam (EB) irradiation on the properties of RTR were studied. The RTR/EVA blends containing 100-0 wt % of RTR were prepared in the internal mixer followed by EB irradiation with doses ranging from 50 to 200 kGy. The RTR/EVA blends were subjected to mechanical, gel content, thermal, and morphological analysis. It was found that the addition of EVA to RTR improved the mechanical properties of RTR. However, results revealed that RTR undergoes irradiation-induced crosslinking in a relatively lesser extent as compared to EVA. This observation is associated with the stabilization and radical scavenging effects of additives, which are present in the RTR matrix.

The American journal of tropical medicine and hygiene, 2003

A nosocomial outbreak of Crimean-Congo hemorrhagic fever occurred in Rawalpindi, Pakistan in Febr... more A nosocomial outbreak of Crimean-Congo hemorrhagic fever occurred in Rawalpindi, Pakistan in February 2002. The identified index case died shortly after admission to a hospital. Two of the health care workers became secondary cases; one of them died on day 13 after coming in contact with the index case. The other secondary case was successfully treated with oral ribavirin.

The American journal of tropical medicine and hygiene, 2005

A 25-year-old woman, later identified as index case of Crimean-Congo hemorrhagic fever (CCHF), pr... more A 25-year-old woman, later identified as index case of Crimean-Congo hemorrhagic fever (CCHF), presented to Holy Family Hospital in Rawalpindi, Pakistan with fever and generalized coagulopathy. A retrospective contact tracing was conducted to explore the modes of exposure possibly associated with transmission of CCHF infection among contacts. We traced 32 contacts of the index case and 158 contacts of secondary cases and tested them for IgG and IgM antibodies against CCHF virus by an enzyme-linked immunosorbent assay technique. According to the type of exposure, contacts were divided into five subsets: percutaneous contact with blood, blood contact to unbroken skin, cutaneous contact to non-sanguineous body fluids, physical contact with patients without body fluids contact, and close proximity without touching. Two out of four contacts who reported percutaneous exposure tested positive for antibodies to CCHF virus. We conclude that simple barrier methods and care in provision of CCH...

PloS one, 2013

The gammaretrovirus termed xenotropic murine leukemia virus-related virus (XMRV) was described to... more The gammaretrovirus termed xenotropic murine leukemia virus-related virus (XMRV) was described to be isolated from prostate cancer tissue biopsies and from blood of patients suffering from chronic fatigue syndrome. However, many studies failed to detect XMRV and to verify these disease associations. Data suggesting the contamination of specimens in particular by PCR-based methods and recent reports demonstrating XMRV generation via recombination of two murine leukemia virus precursors raised serious doubts about XMRV being a genuine human pathogen. To elucidate cell tropism of XMRV, we generated replication competent XMRV reporter viruses encoding a green fluorescent protein or a secretable luciferase as tools to analyze virus infection of human cell lines or primary human cells. Transfection of proviral DNAs into LNCaP prostate cancer cells resulted in readily detectably reporter gene expression and production of progeny virus. Inoculation of known XMRV susceptible target cells rev...

Iranian journal of child neurology, 2013

Spontaneous ventral spinal epidural hematomas are extremely rare in children and clinically recog... more Spontaneous ventral spinal epidural hematomas are extremely rare in children and clinically recognized by the appearance of acute asymmetric focal motor and sensory involvement. In infants, the initial presenting symptoms are very non-specific and irritability is often the only initial manifestation. Appearance of other neurological signs may be delayed up to hours or even days later. In the absence of significant precipitating factors such as severe trauma or previously known coagulopathies, the diagnosis is usually delayed until the full picture of severe cord compression is developed. The diagnosis is finally made by performing magnetic resonance imaging. We report a 5-month-old infant with spinal epidural hematoma who presented with symmetrical upper limb weakness and diaphragmatic involvement to highlight the importance of recognizing the atypical manifestations for early diagnosis and intervention.

Journal of virology, Jan 15, 2015

The role of the accessory viral Nef protein as a multifunctional manipulator of the host cell tha... more The role of the accessory viral Nef protein as a multifunctional manipulator of the host cell that is required for effective replication of human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV) in vivo is well established. It is unknown, however, whether Nef manipulates all or just specific subsets of CD4(+) T cells, which are the main targets of virus infection and differ substantially in their state of activation and importance for a functional immune system. Here, we analyzed the effect of Nef proteins differing in their T cell receptor (TCR)-CD3 downmodulation function in HIV-infected human lymphoid aggregate cultures and peripheral blood mononuclear cells. We found that Nef efficiently downmodulates TCR-CD3 in naive and memory CD4(+) T cells and protects the latter against apoptosis. In contrast, highly proliferative CD45RA(+) CD45RO(+) CD4(+) T cells were main producers of infectious virus but largely refractory to TCR-CD3 downmodulation. Such T cell subse...

Iranian Journal of Child Neurology, 2013

Spontaneous ventral spinal epidural hematomas are extremely rare in children and clinically recog... more Spontaneous ventral spinal epidural hematomas are extremely rare in children and clinically recognized by the appearance of acute asymmetric focal motor and sensory involvement. In infants, the initial presenting symptoms are very non-specific and irritability is often the only initial manifestation. Appearance of other neurological signs may be delayed up to hours or even days later. In the absence of significant precipitating factors such as severe trauma or previously known coagulopathies, the diagnosis is usually delayed until the full picture of severe cord compression is developed. The diagnosis is finally made by performing magnetic resonance imaging. We report a 5-month-old infant with spinal epidural hematoma who presented with symmetrical upper limb weakness and diaphragmatic involvement to highlight the importance of recognizing the atypical manifestations for early diagnosis and intervention.

Word Counts: Abstract = 165 words Text= 53,461 characters (with spaces) ABSTRACT 23 24 The HIV-1 ... more Word Counts: Abstract = 165 words Text= 53,461 characters (with spaces) ABSTRACT 23 24 The HIV-1 Vpu accessory protein is a transmembrane protein that downregulates CD4 25 expression and promotes the release of new virions. We screened a human leukocyte yeast 26 two-hybrid expression library to discover novel Vpu-interacting cellular proteins. The major 27 histocompatibility class II (MHCII) invariant chain, also called Ii or CD74, was found to be 28 one such protein. We show direct binding of Vpu and CD74 using the yeast two-hybrid assay 29 and coimmunoprecipitation from HIV-1 infected cells. The cytoplasmic region of Vpu was 30 found to interact with the 30-amino acid cytoplasmic tail of CD74. Human monocytic U937 31 cells infected with wild type or vpu-defective HIV-1, and transfected cells showed that Vpu 32 down modulated the surface expression of mature MHCII. The reduction in cell surface 33 mature MHCII correlated with decreased antigen-presentation to T cells in culture. Thus, the 34 Vpu protein also contributes to viral persistence by attenuating immune responses during 35 HIV infection. This report further exemplifies the rich diversity and redundancy shown by 36 HIV for immune evasion. 37 A C C E P T E D deficiency syndrome in pig-tailed macaques. Virology 256:54-63.

Chest Journal, Oct 1, 2012

Background: Pulmonary hypertension (PH) is associated with dilatation of main pulmonary artery on... more Background: Pulmonary hypertension (PH) is associated with dilatation of main pulmonary artery on thoracic computerized tomogram (CT). It is not clear whether the diameter of main pulmonary artery is correlated with degree of pulmonary hypertension Objective: To assess the relationship between the degrees of pulmonary artery pressure (PAP) measured by Doppler echocardiography (DE) and pulmonary artery diameter (PAD) and its ratio to ascending aorta (PA/AO) on thoracic CT scan. Methods: Forty eight patients with diagnosis of pulmonary hypertension diagnosed on Doppler echocardiography who had contrasted CT scan of chest were included in the study. The patients were grouped into mild, moderated and severe pulmonary hypertension based on the degree of pulmonary artery pressure. Diameter of main pulmonary artery on contrasted thoracic CT scan just above the bifurcation and its ratio to the diameter of ascending aorta at the same level was measured. Statistical analysis was made to determine the relationship between the degree of PAP and measurements of PAD and PA/AO ratio.

The American Journal of Tropical Medicine and Hygiene, Apr 1, 2005

A 25-year-old woman, later identified as index case of Crimean-Congo hemorrhagic fever (CCHF), pr... more A 25-year-old woman, later identified as index case of Crimean-Congo hemorrhagic fever (CCHF), presented to Holy Family Hospital in Rawalpindi, Pakistan with fever and generalized coagulopathy. A retrospective contact tracing was conducted to explore the modes of exposure possibly associated with transmission of CCHF infection among contacts. We traced 32 contacts of the index case and 158 contacts of secondary cases and tested them for IgG and IgM antibodies against CCHF virus by an enzyme-linked immunosorbent assay technique. According to the type of exposure, contacts were divided into five subsets: percutaneous contact with blood, blood contact to unbroken skin, cutaneous contact to non-sanguineous body fluids, physical contact with patients without body fluids contact, and close proximity without touching. Two out of four contacts who reported percutaneous exposure tested positive for antibodies to CCHF virus. We conclude that simple barrier methods and care in provision of CCHF cases may prevent transmission of this infection.

The anisotropic momentum distribution of photoexcited hot electrons on recombination with holes a... more The anisotropic momentum distribution of photoexcited hot electrons on recombination with holes at the acceptor level produces linearly polarized luminescence. It is found that the degree of linear polarization (DoLP) of the luminescence over the whole width of the first heavy hole peak (0HH) is not constant. Calculations within the spherical approximation show that in bulk GaAs the DoLP over the 0HH peak should vary from zero, at the low energy side, to its maximum value (0.33), at the high energy side of the 0HH peak, for the electric vector of excitation hat {e}\vert \vert [110] excitation geometry and vice versa for the hat {e}\vert \vert [100] excitation geometry. This variation in the DoLP over the 0HH peak will be referred to as the anisotropy of the DoLP and arises as a direct result of the warping of the heavy hole sub-band. Experimental results were found in qualitative agreement with the calculations under spherical approximation. The calculations within the diagonal approximation could not account for the unexpectedly high value of the DoLP towards the low energy side of the 0HH peak.

Turkish Journal of Physics, 2004

Developer composition type and development technique are known to influence surface and edge roug... more Developer composition type and development technique are known to influence surface and edge roughness in polymethylemethacrylate (PMMA); and it is during development, we believe, that the result is most influenced by the phase separation into polymer-rich and polymer-poor regions. This polymer phase separation is more prominent in a weaker developer and low temperature. In this paper, we investigate the effect of development time on the extent of polymer phase separation in an exposed PMMA developed in a standard developer i.e. 1:3 MIBK:IPA at 20 °C and rinsed in pure IPA for 30 sec. The polymer phase separation is found to increase with the development time.

Journal of Personality Assessment, 2015

International Journal of Nanoscience

Carbon nanotubes (CNTs) have been successfully synthesized by using in-house fabricated Double St... more Carbon nanotubes (CNTs) have been successfully synthesized by using in-house fabricated Double Stage Chemical Vapor Deposition (DS-CVD) technique, using acetylene (C2H2) and hydrogen (H2) as the precursor gases. The purity, morphology and the structure of CNTs were then characterized using Field Emission Scanning Microscope (FESEM), Transmission Electron Microscope (TEM) and Thermogravimetric Analysis (TGA). The effects of the process parameters were examined whereby the experimental design of the investigation was conducted using Design Expert® Version 6.0.8. The statistical analysis reveals that the optimized conditions for the best CNTs yield production at 850°C reaction temperature, 60 min reaction time, with gas flow rates at 40 and 150 ml/min for C2H2 and H2, respectively. The CNTs produced were successfully used as column chromatographic media. Due to its nanosized structured dimension, CNTs' have tremendously large surface area and that lead to highly efficient protein p...

Annals of Saudi medicine

Middle Eastern respiratory syndrome caused by novel coronavirus (MERS CoV) has been a major publi... more Middle Eastern respiratory syndrome caused by novel coronavirus (MERS CoV) has been a major public health challenge since it was first described in 2012 in Saudi Arabia. So far, there is no effective treatment for this serious illness, which features a high mortality rate. We report an initial experience of the use of ribavirin and interferon (IFN)-a2b in the management of MERS CoV at a tertiary care hospital. A case series of 6 patients admitted with a confirmed diagnosis of MERS CoV were treated with ribavirin and IFN-a2b in addition to supportive management. The patients' demographics, clinical parameters, and outcomes were recorded. Fifty-four close contacts of these patients were screened for MERS CoV. Six patients with MERS CoV infection were included in this study. Four cases featured symptomatic disease, including pneumonia and respiratory failure, while 2 were asymptomatic close contacts of the MERS CoV patients. The MERS CoV infection was confirmed by reverse transcrip...

A numerical study on heat transfer enhancement utilizing nanofluids in a two-dimensional enclosur... more A numerical study on heat transfer enhancement utilizing nanofluids in a two-dimensional enclosure was investigated for various pertinent parameters using commercial CFD code FLUENT 6.3. Numerical simulations were carried out assuming nanofluid as single phase. Effect of Rayleigh number ranging from 6 3 10 10 ≤ ≤ Ra and nanoparticle volume fraction (0-20%) was studied on flow pattern and energy transport within the thermal boundary layer for aspect ratio of 1.0. Stream function and isotherm contours were plotted for all the above mentioned parameters. Results show that effect of buoyancy parameter and volume fraction causes increase in average heat transfer enhancement. The results were also compared with the khanafer's model and found to be in good agreement.

Journal of Applied Polymer Science, 2014

Scrap rubber reclamation is one of the most desirable approaches to solve the disposal problem of... more Scrap rubber reclamation is one of the most desirable approaches to solve the disposal problem of used tires. However, reclaimed tire rubber (RTR) has not gained enough attention due to its poor properties. In this work, the effects of poly(ethylene-covinyl acetate) (EVA) addition and electron beam (EB) irradiation on the properties of RTR were studied. The RTR/EVA blends containing 100-0 wt % of RTR were prepared in the internal mixer followed by EB irradiation with doses ranging from 50 to 200 kGy. The RTR/EVA blends were subjected to mechanical, gel content, thermal, and morphological analysis. It was found that the addition of EVA to RTR improved the mechanical properties of RTR. However, results revealed that RTR undergoes irradiation-induced crosslinking in a relatively lesser extent as compared to EVA. This observation is associated with the stabilization and radical scavenging effects of additives, which are present in the RTR matrix.

The American journal of tropical medicine and hygiene, 2003

A nosocomial outbreak of Crimean-Congo hemorrhagic fever occurred in Rawalpindi, Pakistan in Febr... more A nosocomial outbreak of Crimean-Congo hemorrhagic fever occurred in Rawalpindi, Pakistan in February 2002. The identified index case died shortly after admission to a hospital. Two of the health care workers became secondary cases; one of them died on day 13 after coming in contact with the index case. The other secondary case was successfully treated with oral ribavirin.

The American journal of tropical medicine and hygiene, 2005

A 25-year-old woman, later identified as index case of Crimean-Congo hemorrhagic fever (CCHF), pr... more A 25-year-old woman, later identified as index case of Crimean-Congo hemorrhagic fever (CCHF), presented to Holy Family Hospital in Rawalpindi, Pakistan with fever and generalized coagulopathy. A retrospective contact tracing was conducted to explore the modes of exposure possibly associated with transmission of CCHF infection among contacts. We traced 32 contacts of the index case and 158 contacts of secondary cases and tested them for IgG and IgM antibodies against CCHF virus by an enzyme-linked immunosorbent assay technique. According to the type of exposure, contacts were divided into five subsets: percutaneous contact with blood, blood contact to unbroken skin, cutaneous contact to non-sanguineous body fluids, physical contact with patients without body fluids contact, and close proximity without touching. Two out of four contacts who reported percutaneous exposure tested positive for antibodies to CCHF virus. We conclude that simple barrier methods and care in provision of CCH...

PloS one, 2013

The gammaretrovirus termed xenotropic murine leukemia virus-related virus (XMRV) was described to... more The gammaretrovirus termed xenotropic murine leukemia virus-related virus (XMRV) was described to be isolated from prostate cancer tissue biopsies and from blood of patients suffering from chronic fatigue syndrome. However, many studies failed to detect XMRV and to verify these disease associations. Data suggesting the contamination of specimens in particular by PCR-based methods and recent reports demonstrating XMRV generation via recombination of two murine leukemia virus precursors raised serious doubts about XMRV being a genuine human pathogen. To elucidate cell tropism of XMRV, we generated replication competent XMRV reporter viruses encoding a green fluorescent protein or a secretable luciferase as tools to analyze virus infection of human cell lines or primary human cells. Transfection of proviral DNAs into LNCaP prostate cancer cells resulted in readily detectably reporter gene expression and production of progeny virus. Inoculation of known XMRV susceptible target cells rev...

Iranian journal of child neurology, 2013

Spontaneous ventral spinal epidural hematomas are extremely rare in children and clinically recog... more Spontaneous ventral spinal epidural hematomas are extremely rare in children and clinically recognized by the appearance of acute asymmetric focal motor and sensory involvement. In infants, the initial presenting symptoms are very non-specific and irritability is often the only initial manifestation. Appearance of other neurological signs may be delayed up to hours or even days later. In the absence of significant precipitating factors such as severe trauma or previously known coagulopathies, the diagnosis is usually delayed until the full picture of severe cord compression is developed. The diagnosis is finally made by performing magnetic resonance imaging. We report a 5-month-old infant with spinal epidural hematoma who presented with symmetrical upper limb weakness and diaphragmatic involvement to highlight the importance of recognizing the atypical manifestations for early diagnosis and intervention.

Journal of virology, Jan 15, 2015

The role of the accessory viral Nef protein as a multifunctional manipulator of the host cell tha... more The role of the accessory viral Nef protein as a multifunctional manipulator of the host cell that is required for effective replication of human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV) in vivo is well established. It is unknown, however, whether Nef manipulates all or just specific subsets of CD4(+) T cells, which are the main targets of virus infection and differ substantially in their state of activation and importance for a functional immune system. Here, we analyzed the effect of Nef proteins differing in their T cell receptor (TCR)-CD3 downmodulation function in HIV-infected human lymphoid aggregate cultures and peripheral blood mononuclear cells. We found that Nef efficiently downmodulates TCR-CD3 in naive and memory CD4(+) T cells and protects the latter against apoptosis. In contrast, highly proliferative CD45RA(+) CD45RO(+) CD4(+) T cells were main producers of infectious virus but largely refractory to TCR-CD3 downmodulation. Such T cell subse...

What is NATO, what is the role of NATO and to what extent NATO played significant role in the Mid... more What is NATO, what is the role of NATO and to what extent NATO played significant role in the Middle East

The history of globalization goes back to the second half of the twentieth century. The growth of... more The history of globalization goes back to the second half of the twentieth century. The growth of transportation and communication technology networks linking different parts of the

the purpose of this paper is to shed light to some contested terms between Islam and violence suc... more the purpose of this paper is to shed light to some contested terms between Islam and violence such Jihad, holy war and other disputed terms.

Thesis: Mythological thinking has a profound effect on the way it constructs culture, and constit... more Thesis: Mythological thinking has a profound effect on the way it constructs culture, and constitute a language and a system of significations. Mythical language, symbols, and social systems have been used as fabric for the unity of Shia from legitimacy to political forces.