R. Ahmed

Publication List Details

Period

1995 - 2007

Number

104

Co-Authors

Region-Based Shape Incorporation for Probabilistic Spatio-Temporal Video Object Segmentation (2006)

Ahmed, R., Karmakar, G. C., Dooley, L. S.

Embedding generic shape information into probabilistic spatio-temporal video object segmentation is of pivotal importance to achieving better segmentation, since it provides valuable perceptual clues...

Probabilistic Spatio-Temporal Video Object Segmentation Incorporating Shape Information (2006)

Ahmed, R., Karmakar, G. C., Dooley, L. S.

From a video object segmentation perspective, using a joint spatio-temporal strategy is superior to processing with priority in either the spatial or temporal domains, as it considers a video...

Quantifying cell turnover using CFSE data (2005)

Ganusov, V.V., Pilyugin, S.S., Boer, R.J. De, Murali-Krishna, K., Ahmed, R., Antia, R.

The CFSE dye dilution assay is widely used to determine the number of divisions a given CFSE labelled cell has undergone in vitro and in vivo. In this paper, we consider how the data obtained with...

In vitro Rapid Propagation of Black Thorn (Kaempferia galanga L.): A Rare Medicinal and Aromatic Plant of Bangladesh (2005)

M.M. Rahman, M.N. Amin, T. Ahamed, S. Ahmad, A. Habib, R. Ahmed, ...

An efficient protocol has been established for rapid production of plantlets using rhizome tip and lateral bud explants of the field grown plant. The explants were cultured on MS medium with auxins...

Large Scale Plant Regeneration in vitro from Leaf Derived Callus Cultures of Pineapple [Ananas comosus (L.) Merr. cv. Giant Kew] (2005)

M.N. Amin, M.M. Rahman, K.W. Rahman, R. Ahmed, M.S. Hossain, M.B. Ahmed

The leaf base explants from the in vitro established shoot cultures were induced to form callus and subsequently to differentiate into shoots on MS medium supplemented with different concentrations...

In vitro Rooting Performance of Native-olive (Elaeocarpus robustus Roxb.) under Different Auxins and High Temperature Treatments (2004)

M.M. Rahman, M.N. Amin, S. Ahmad, R. Ahmed

Micropropagation of native-olive (Elaeocarpus robustus Roxb.) has been proved difficult due very slow rooting of the shoot cuttings. The objective of the present investigation was to develop a...

In vitro Plantlet Regeneration from Internode Explant of Native-olive (Elaeocarpus robustus roxb.) (2004)

M.M. Rahman, M.N. Amin, R. Ahmed, F. Begum

Regeneration of multiple shoots via callus induction and organogenesis were achieved in native-olive (Elaeocarpus robustus). Callus induction and shoot buds regeneration were obtained from internode...

In vitro Rapid Regeneration from Cotyledon Explant of Native-olive (Elaeocarpus robustus Roxb.) (2004)

M.M. Rahman, M.N. Amin, R. Ahmed

In the present study an efficient tissue culture method for high rate of shoot regeneration was developed for Elaeocarpus robustus. Cotyledonary explants with and without petiolar end were cultured...

In vitro Regeneration of Plantlets of Curcuma longa Linn. A Valuable Spice Plant in Bangladesh (2004)

M.M. Rahman, M.N. Amin, H.S. Jahan, R. Ahmed

Sprouted rhizome buds were collected from the field grown one year old rhizomes and surface sterilized by treating them with 0.1% HgCl2 for 14 min. The dissected rhizome bud explants (ca.1 cm) of...

Suppressive Effects of Aqueous Extracts of Azadirachta indica Leaf on Some Initial Growth Parameters of Six Common Agricultural Crops (2003)

M.B. Uddin, R. Ahmed, M.K. Hossain

The paper presents the suppressive effect of different concentration of aqueous leaf extracts of Neem (Azadirachta indica) on some agricultural crops e.g. Cicer arietinum L., Brassica juncea (L.)...

Diversity of Butterflies from District Bagh, Azad Kashmir (2003)

M. Rafique Khan, R. Ahmed, M. Rahim Khan, A. Hayat, M. Khalid

The adult butterflies were collected from ten localities of Distt. Bagh through out the year 1998. A total of 27 species belonging to 5 families and 15 genera were collected. Diversity was calculated...

X-38 Bolt Retractor Subsystem Separation Demonstration (2002)

Johnston, A.S., Ahmed, R., Garrison, J.C., Gaines, J.L., Waggoner, J.D.

The Flight Robotics Laboratory (FRL) successfully demonstrated the X-38 bolt retractor subsystem (BRS). The BRS design was proven safe by testing in the Pyrotechnic Shock Facility (PSF) before being...

Recruitment Times, Proliferation, and Apoptosis Rates during the CD8+ T-Cell Response to Lymphocytic Choriomeningitis Virus (2001)

Boer, R.J. De, Oprea, M. (Mihaela), Antia, R. (Rustom), Murali-Krishna, K. (Kaja), Ahmed, R. (Rafi), Perelson, A.S. (Alan)

The specific CD8+ T-cell response during acute lymphocytic choriomeningitis virus (LCMV) infection of mice is characterized by a rapid proliferation phase, followed by a rapid death phase and...

Design and Test of Low-Profile Composite Aerospace Tank Dome (MSFC Center Director's Discretionary Fund Final Report, Project No. 96-28) (1999)

Ahmed, R.

This report summarizes the design, analysis, manufacture, and test of a subscale, low-profile composite aerospace dome under internal pressure. A low-profile dome has a radius-to-height ratio greater...

Cyclic Loads Tests of Carbon Involute Solid Rocket Motor Outer Boot Ring Segments. (1998)

Ahmed, R.

On December 23, 1987, a Solid Rocket Motor (SRM) nozzle Outer Boot Ring (OBR) failed at the end of the Development Motor 9 (DM-9) test firing in Utah. This ring was constructed of carbon cloth...

Analysis of Stress Concentration in the Dutton Groove Regions of the Super Lightweight External Tank (1995)

Ahmed, R.

Because the 2195 aluminum-lithium material of the super lightweight external tank (SLWTET) has a lower toughness than the 2219 aluminum used in previous ET's, careful attention must be paid to stress...

Analysis of Stress Concentration at Holes in Components Made of 2195 Aluminum-Lithium (1995)

Ahmed, R.

Because the 2195 aluminum-lithium of the super lightweight external tank (SLWT ET) has a lower toughness than the 2219 aluminum used in previous ET's, careful attention must be paid to stress...

A common major histocompatibility complex class II allele HLA-DQB1* 0301 is present in clinical variants of pemphigoid.

Delgado, J C, Turbay, D, Yunis, E J, Yunis, J J, Morton, E D, Bhol, K, ...

Bullous pemphigoid (BP) is an autoimmune subepidermal blistering disease seen primarily in elderly persons. It is characterized clinically by the development of tense bullae and by the presence of an...

Recombinant Listeria monocytogenes as a live vaccine vehicle for the induction of protective anti-viral cell-mediated immunity.

Shen, H, Slifka, M K, Matloubian, M, Jensen, E R, Ahmed, R, Miller, J F

Listeria monocytogenes (LM) is a Gram-positive bacterium that is able to enter host cells, escape from the endocytic vesicle, multiply within the cytoplasm, and spread directly from cell to cell...

Immune function in mice lacking the perforin gene.

Walsh, C M, Matloubian, M, Liu, C C, Ueda, R, Kurahara, C G, Christensen, J L, ...

Mice lacking the perforin gene were generated by using targeted gene disruption in embryonal stem cells. When infected with lymphocytic choriomeningitis virus (LCMV), perforin-less (-/-) mice showed...

Impaired responsiveness to gamma interferon of macrophages infected with lymphocytic choriomeningitis virus clone 13: susceptibility to histoplasmosis.

Villarete, L, De Fries, R, Kolhekar, S, Howard, D, Ahmed, R, Wu-Hsieh, B

Lymphocytic choriomeningitis virus clone 13 (LCMV clone 13), a variant isolated from the spleens of neonatally infected mice, causes persistent infections in mice infected as adults. Such...

Immunization with nonstructural proteins E1 and E2 of cottontail rabbit papillomavirus stimulates regression of virus-induced papillomas.

Selvakumar, R, Borenstein, L A, Lin, Y L, Ahmed, R, Wettstein, F O

Cottontail rabbit papillomavirus is the major animal model for cancer-associated papillomaviruses. Here we show that vaccination with the nonstructural proteins E1 and E2 induces the regression of...

Bone marrow is a major site of long-term antibody production after acute viral infection.

Slifka, M K, Matloubian, M, Ahmed, R

Antiviral antibody production is often sustained for long periods after resolution of an acute viral infection. Despite extensive documentation of this phenomenon, the mechanisms involved in...

DNA vaccination against persistent viral infection.

Martins, L P, Lau, L L, Asano, M S, Ahmed, R

This study shows that DNA vaccination can confer protection against a persistent viral infection by priming CD8+ cytotoxic T lymphocytes (CTL). Adult BALB/c (H-2d) mice were injected intramuscularly...

Antiviral cytotoxic T-cell memory by vaccination with recombinant Listeria monocytogenes.

Slifka, M K, Shen, H, Matloubian, M, Jensen, E R, Miller, J F, Ahmed, R

Listeria monocytogenes is a facultative intracellular bacterium that is able to escape phagocytic vesicles and replicate in the cytoplasm of infected cells. As with viral vectors, this...

CD40 ligand-deficient mice generate a normal primary cytotoxic T-lymphocyte response but a defective humoral response to a viral infection.

Whitmire, J K, Slifka, M K, Grewal, I S, Flavell, R A, Ahmed, R

CD40 ligand is expressed on activated T cells and interacts with CD40 on B cells and monocytes. It is not known what role CD40 ligand plays in the generation of immune responses to viral infection....

Uncovering subdominant cytotoxic T-lymphocyte responses in lymphocytic choriomeningitis virus-infected BALB/c mice.

Van Der Most, R G, Concepcion, R J, Oseroff, C, Alexander, J, Southwood, S, Sidney, J, ...

The cytotoxic T-lymphocyte response against lymphocytic choriomeningitis virus (LCMV) in BALB/c mice is predominantly directed against a single, Ld-restricted epitope in the viral nucleoprotein...

Regression of papillomas induced by cottontail rabbit papillomavirus is associated with infiltration of CD8+ cells and persistence of viral DNA after regression.

Selvakumar, R, Schmitt, A, Iftner, T, Ahmed, R, Wettstein, F O

Cottontail rabbit papillomavirus (CRPV) is a highly oncogenic papillomavirus and has been successfully used as a model to develop protective vaccines against papillomaviruses. Papillomas induced by...

Recombinant Listeria monocytogenes vaccination eliminates papillomavirus-induced tumors and prevents papilloma formation from viral DNA.

Jensen, E R, Selvakumar, R, Shen, H, Ahmed, R, Wettstein, F O, Miller, J F

Listeria monocytogenes is a gram-positive, facultative intracellular bacterium that enters the cytoplasm of infected cells and spreads directly into neighboring cells without encountering the...

Bacillus cereus phage typing as an epidemiological tool in outbreaks of food poisoning.

Ahmed, R, Sankar-Mistry, P, Jackson, S, Ackermann, H W, Kasatiya, S S

Bacillus cereus is responsible for an increasing number of food poisoning cases. By using 12 bacteriophages isolated from sewage, a typing scheme for B. cereus isolates from outbreaks or sporadic...

T-cell response to cottontail rabbit papillomavirus structural proteins in infected rabbits.

Selvakumar, R, Borenstein, L A, Lin, Y L, Ahmed, R, Wettstein, F O

Cottontail rabbit papillomavirus (CRPV)-induced papillomas progress at a high frequency to carcinomas and thus can serve as a model for high-cancer-risk human papillomavirus infection. Previously, we...

Tissue-mediated selection of viral variants: correlation between glycoprotein mutation and growth in neuronal cells.

Villarete, L, Somasundaram, T, Ahmed, R

Viral variants with different biological properties predominate in the central nervous system (CNS) and lymphoid tissues of carrier mice infected at birth with the Armstrong strain of lymphocytic...

CD4+ T cells are required to sustain CD8+ cytotoxic T-cell responses during chronic viral infection.

Matloubian, M, Concepcion, R J, Ahmed, R

In this study, we have examined the relative contributions of CD4+ and CD8+ T cells in controlling an acute or chronic lymphocytic choriomeningitis virus (LCMV) infection. To study acute infection,...

Progression from papilloma to carcinoma is accompanied by changes in antibody response to papillomavirus proteins.

Lin, Y L, Borenstein, L A, Selvakumar, R, Ahmed, R, Wettstein, F O

Cottontail rabbit papillomavirus induces benign tumors, papillomas, in rabbits which progress at a high frequency to malignant tumors, carcinomas. Cottontail rabbit papillomavirus therefore provides...

Cottontail rabbit papillomavirus L1 protein-based vaccines: protection is achieved only with a full-length, nondenatured product.

Lin, Y L, Borenstein, L A, Ahmed, R, Wettstein, F O

Papillomas induced by the cottontail rabbit papillomavirus (CRPV) progress at a high frequency to carcinomas. In this regard, CRPV and its tumors can serve as an animal model for highly oncogenic...

Molecular determinants of macrophage tropism and viral persistence: importance of single amino acid changes in the polymerase and glycoprotein of lymphocytic choriomeningitis virus.

Matloubian, M, Kolhekar, S R, Somasundaram, T, Ahmed, R

This study documents that the immunosuppressive lymphocytic choriomeningitis virus (LCMV) variant, clone 13, shows a specific predilection for enhanced infection of macrophages both in vitro and in...

Viral infection of the thymus.

King, C C, Jamieson, B D, Reddy, K, Bali, N, Concepcion, R J, Ahmed, R

We have examined infection of the thymus during congenitally acquired chronic lymphocytic choriomeningitis virus (LCMV) infection of mice, a classic model of antigen-specific T-cell tolerance. Our...

In vivo selection of lymphocyte-tropic and macrophage-tropic variants of lymphocytic choriomeningitis virus during persistent infection.

King, C C, De Fries, R, Kolhekar, S R, Ahmed, R

This study demonstrates cell-specific selection of viral variants during persistent lymphocytic choriomeningitis virus infection in its natural host. We have analyzed viral isolates obtained from...

Molecular basis of organ-specific selection of viral variants during chronic infection.

Ahmed, R, Hahn, C S, Somasundaram, T, Villarete, L, Matloubian, M, Strauss, J H

Viral variants of different phenotypes are present in the central nervous system (CNS) and lymphoid tissues of carrier mice infected at birth with the Armstrong strain of lymphocytic choriomeningitis...

T4+ T helper cell function in vivo: differential requirement for induction of antiviral cytotoxic T-cell and antibody responses.

Ahmed, R, Butler, L D, Bhatti, L

This study documents the differential requirements of T4+ T helper cells in the induction of virus-specific cytotoxic T-lymphocyte (CTL) and antibody responses during acute lymphocytic...

Genetic analysis of in vivo-selected viral variants causing chronic infection: importance of mutation in the L RNA segment of lymphocytic choriomeningitis virus.

Ahmed, R, Simon, R S, Matloubian, M, Kolhekar, S R, Southern, P J, Freedman, D M

Viral variants with different biological properties are present in the central nervous systems (CNS) and lymphoid tissues of mice persistently infected with lymphocytic choriomeningitis virus (LCMV)....

Virus-lymphocyte interaction: T cells of the helper subset are infected with lymphocytic choriomeningitis virus during persistent infection in vivo.

Ahmed, R, King, C C, Oldstone, M B

The lifelong persistence of lymphocytic choriomeningitis virus (LCMV) in neonatally or congenitally infected mice is accompanied by a suppression of virus-specific T-cell responses. In this study, we...

Virus specificity of cytotoxic T lymphocytes generated during acute lymphocytic choriomeningitis virus infection: role of the H-2 region in determining cross-reactivity for different lymphocytic choriomeningitis virus strains.

Ahmed, R, Byrne, J A, Oldstone, M B

We have compared the relatedness of five different strains of lymphocytic choriomeningitis virus (LCMV) as assessed by LCMV-specific cytotoxic T lymphocytes (CTL). Several different mouse strains...

The S RNA segment of lymphocytic choriomeningitis virus codes for the nucleoprotein and glycoproteins 1 and 2.

Riviere, Y, Ahmed, R, Southern, P J, Buchmeier, M J, Dutko, F J, Oldstone, M B

The lymphocytic choriomeningitis virus (LCMV) genome consists of a large RNA segment and a small RNA segment. The three major structural proteins of this virus are an internal nucleoprotein and two...

Genetic mapping of lymphocytic choriomeningitis virus pathogenicity: virulence in guinea pigs is associated with the L RNA segment.

Riviere, Y, Ahmed, R, Southern, P J, Buchmeier, M J, Oldstone, M B

The Armstrong CA 1371 (ARM) and WE strains of lymphocytic choriomeningitis virus (LCMV) differ in the ability to produce disease in adult guinea pigs. Infection with the ARM strain is not lethal,...

Immune therapy of a persistent and disseminated viral infection.

Ahmed, R, Jamieson, B D, Porter, D D

The mechanism of viral clearance was studied by using the mouse model of chronic infection with lymphocytic choriomeningitis virus. Distinct patterns of viral clearance and histopathology were...

Effective clearance of a persistent viral infection requires cooperation between virus-specific Lyt2+ T cells and nonspecific bone marrow-derived cells.

Jamieson, B D, Butler, L D, Ahmed, R

The lifelong chronic lymphocytic choriomeningitis virus (LCMV) infection established in neonatally or congenitally infected mice can be eliminated by adoptive transfer of lymphoid cells from...

Characterization of Escherichia coli serotype O157:H7.

Ratnam, S, March, S B, Ahmed, R, Bezanson, G S, Kasatiya, S

A total of 174 strains of Escherichia coli serotype O157:H7 representing human isolates obtained from outbreaks and sporadic cases of hemorrhagic colitis, hemolytic-uremic syndrome, and nonbloody...

T-cell tolerance: exposure to virus in utero does not cause a permanent deletion of specific T cells.

Jamieson, B D, Ahmed, R

This study documents the curing of a congenitally acquired chronic viral infection and the acquisition of T-cell competence by a previously tolerant host. Infection of mice with lymphocytic...

Genetic variation during lytic reovirus infection: high-passage stocks of wild-type reovirus contain temperature-sensitive mutants.

Ahmed, R, Chakraborty, P R, Fields, B N

Wild-type clones of reovirus serotypes 1 (Lang), 2 (Jones), and 3 (Dearing) were serially passaged in L cells at a high multiplicity of infection, and the virus population was examined at passage...

Molecular Typing and Distribution of Staphylococcus aureus Isolates in Eastern Canadian Dairy Herds†

Sabour, P. M., Gill, J. J., Lepp, D., Pacan, J. C., Ahmed, R., Dingwell, R., ...

Macrorestriction analysis of SmaI-digested chromosomal DNA, using pulsed field gel electrophoresis (PFGE) was performed to type and estimate genetic relationships among 288 Staphylococcus aureus...

Persistent Infections in L Cells with Temperature-Sensitive Mutants of Reovirus

Ahmed, R., Graham, A. F.

Serial passage of reovirus temperature-sensitive (ts) mutant C(447) produced by passage 9 (P9) a heavily defective population of virus from which the double-stranded RNA genomic segments L1, L3, and...

A camera that directly measures physical parameters.

Ahmed, R, Vernon, S A

Accurate measurement of physical parameters is essential for the practice of modern medicine and ophthalmology in particular. A measuring device is presented that combines a single lens reflex (SLR)...

A common major histocompatibility complex class II allele HLA-DQB1* 0301 is present in clinical variants of pemphigoid.

Delgado, J C, Turbay, D, Yunis, E J, Yunis, J J, Morton, E D, Bhol, K, ...

Bullous pemphigoid (BP) is an autoimmune subepidermal blistering disease seen primarily in elderly persons. It is characterized clinically by the development of tense bullae and by the presence of an...

Recombinant Listeria monocytogenes as a live vaccine vehicle for the induction of protective anti-viral cell-mediated immunity.

Shen, H, Slifka, M K, Matloubian, M, Jensen, E R, Ahmed, R, Miller, J F

Listeria monocytogenes (LM) is a Gram-positive bacterium that is able to enter host cells, escape from the endocytic vesicle, multiply within the cytoplasm, and spread directly from cell to cell...

Immune function in mice lacking the perforin gene.

Walsh, C M, Matloubian, M, Liu, C C, Ueda, R, Kurahara, C G, Christensen, J L, ...

Mice lacking the perforin gene were generated by using targeted gene disruption in embryonal stem cells. When infected with lymphocytic choriomeningitis virus (LCMV), perforin-less (-/-) mice showed...

Impaired responsiveness to gamma interferon of macrophages infected with lymphocytic choriomeningitis virus clone 13: susceptibility to histoplasmosis.

Villarete, L, De Fries, R, Kolhekar, S, Howard, D, Ahmed, R, Wu-Hsieh, B

Lymphocytic choriomeningitis virus clone 13 (LCMV clone 13), a variant isolated from the spleens of neonatally infected mice, causes persistent infections in mice infected as adults. Such...

Immunization with nonstructural proteins E1 and E2 of cottontail rabbit papillomavirus stimulates regression of virus-induced papillomas.

Selvakumar, R, Borenstein, L A, Lin, Y L, Ahmed, R, Wettstein, F O

Cottontail rabbit papillomavirus is the major animal model for cancer-associated papillomaviruses. Here we show that vaccination with the nonstructural proteins E1 and E2 induces the regression of...

Bone marrow is a major site of long-term antibody production after acute viral infection.

Slifka, M K, Matloubian, M, Ahmed, R

Antiviral antibody production is often sustained for long periods after resolution of an acute viral infection. Despite extensive documentation of this phenomenon, the mechanisms involved in...

DNA vaccination against persistent viral infection.

Martins, L P, Lau, L L, Asano, M S, Ahmed, R

This study shows that DNA vaccination can confer protection against a persistent viral infection by priming CD8+ cytotoxic T lymphocytes (CTL). Adult BALB/c (H-2d) mice were injected intramuscularly...

Antiviral cytotoxic T-cell memory by vaccination with recombinant Listeria monocytogenes.

Slifka, M K, Shen, H, Matloubian, M, Jensen, E R, Miller, J F, Ahmed, R

Listeria monocytogenes is a facultative intracellular bacterium that is able to escape phagocytic vesicles and replicate in the cytoplasm of infected cells. As with viral vectors, this...

CD40 ligand-deficient mice generate a normal primary cytotoxic T-lymphocyte response but a defective humoral response to a viral infection.

Whitmire, J K, Slifka, M K, Grewal, I S, Flavell, R A, Ahmed, R

CD40 ligand is expressed on activated T cells and interacts with CD40 on B cells and monocytes. It is not known what role CD40 ligand plays in the generation of immune responses to viral infection....