sepideh m - Academia.edu (original) (raw)
Papers by sepideh m
PLOS One, 2012
Neurotrophins (NTs) are a family of secreted growth factor proteins primarily involved in the reg... more Neurotrophins (NTs) are a family of secreted growth factor proteins primarily involved in the regulation of survival and appropriate development of neural cells, functioning by binding to their specific (TrkA, TtkB, and TrkC) and/or common NGFR receptor. NGFR is the common receptor of NTs, binding with low-affinity to all members of the family. Among different functions assigned to NGFR, it is also involved in apoptosis induction and tumorigenesis processes. Interestingly, some of the functions of NGFR appear to be ligand-independent, suggesting a probable involvement of non-coding RNA residing within the sequence of the gene. Here, we are reporting the existence of a conserved putative microRNA, named Hsa-mir-6165 [EBI accession#: FR873488]. Transfection of a DNA segment corresponding to the pre-mir-6165 sequence in Hela cell line caused the generation of mature exogenous mir-6165 (a ,200,000 fold overexpression). Furthermore, using specific primers, we succeeded to detect the endogenous expression of mir-6165 in several glioma cell lines and glioma primary tumors known to express NGFR. Similar to the pro-apoptotic role of NGFR in some cell types, overexpression of premir-6165 in U87 cell line resulted in an elevated rate of apoptosis. Moreover, coordinated with the increased level of mir-6165 in the transfected U87 cell line, two of its predicted target genes (Pkd1 and DAGLA) were significantly down-regulated. The latter findings suggest that some of the previously attributed functions of NGFR could be explained indirectly by cotranscription of mir-6165 in the cells.
Skull Base-an Interdisciplinary Approach, 2005
Cerebral revascularization continues to evolve as an option in the setting of ischemia. The poten... more Cerebral revascularization continues to evolve as an option in the setting of ischemia. The potential to favorably influence stroke risk and the natural history of cerebrovascular occlusive disease is being evaluated by the ongoing Carotid Occlusion Surgery Study and the Japanese Extracranial-Intracranial Bypass Trial. For those patients who undergo bypass in the setting of ischemia, four key areas of follow-up include functional neurological status, neurocognitive status, bypass patency, and status of cerebral blood flow and perfusion. Several stroke scales that can be used to assess functional status include the National Institutes of Health Stroke Scale, Bathel Index, Modified Rankin Scale, and Stroke Specific Quality of Life. Neurocognition can be checked using the Repeatable Battery for the Assessment of Neuropsychological Status, among other tests. Bypass patency is checked intraoperatively using various flow probes and postoperatively using magnetic resonance angiography (MRA) or computed tomographic angiography (CTA). Cerebral blood flow and perfusion can be assessed using a host of modalities that include positron emission tomography (PET), xenon CT, single photon emission computed tomography (SPECT), transcranial Doppler (TCD), CT, and MR. Paired blood flow studies after a cerebral vasodilatory stimulus using one of these modalities can determine the state of autoregulatory vasodilation (Stage 1 hemodynamic compromise). However, only PET with oxygen extraction fraction measurements can reliably assess for Stage 2 compromise (misery perfusion). This article discusses the various clinical, neuropsychological, and radiographic techniques available to assess a patient's clinical state and cerebral blood flow before and after cerebral revascularization.
This paper introduces a human actions recognition framework based on multiple types of features. ... more This paper introduces a human actions recognition framework based on multiple types of features. Taking the advantage of motion-selectivity property of 3D dual-tree complex wavelet transform (3D DT-CWT) and affine SIFT local image detector, firstly spatio-temporal and local static features are extracted. No assumptions of scene background, location, objects of interest, or point of view information are made whereas bidirectional two-dimensional PCA (2D-PCA) is employed for dimensionality reduction which offers enhanced capabilities to preserve structure and correlation amongst neighborhood pixels of a video frame. The proposed technique is significantly faster than traditional methods due to volumetric processing of input video, and offers a rich representation of human actions in terms of reduction in artifacts. Experimental examples are given to illustrate the effectiveness of the approach.
Pm&r
Objective: To evaluate the relationship between disability and both health-related quality of lif... more Objective: To evaluate the relationship between disability and both health-related quality of life (HRQoL) and caregiver burden in patients with upper limb poststroke spasticity.
BMC Proceedings, 2011
Introduction / objectivesWHO African Partnerships for Patient Safety (APPS) nurtures sustainable ... more Introduction / objectivesWHO African Partnerships for Patient Safety (APPS) nurtures sustainable partnerships between African and European hospitals to improve patient safety. Through APPS, Hôpitaux Universitaires de Genève (HUG) is partnered with hospitals in Cameroon, Mali and Senegal.MethodsHospital representatives convened in 2009 to build the programme foundation, followed by hospital situational analyses to determine priority action areas. Among 12 patient safety action areas, reduction of health care-associated infection (HAI) was chosen as a common platform of action. Subsequently, 2-year partnership action plans were developed, finalized at a workshop in 2009 in Uganda. Hand hygiene (HH), the single most effective measure to reduce HAI, was the cornerstone of planned action.ResultsA broad range of HH improvement tools was made available through a patient safety resource map. African technicians were trained on alcohol-based handrub production. An initial batch of materials was ...
Archives of Physical Medicine and Rehabilitation, 2006
Haghpanah S, Bogie K, Wang X, Banks PG, Ho CH. Reliability of electronic versus manual wound meas... more Haghpanah S, Bogie K, Wang X, Banks PG, Ho CH. Reliability of electronic versus manual wound measurement techniques. Arch Phys Med Rehabil 2006;87: 1396-402.
Journal of Biomedical Materials Research Part A, 2009
Cells in vivo encounter with and react to the extracellular matrix materials on a nanometer scale... more Cells in vivo encounter with and react to the extracellular matrix materials on a nanometer scale. Recent advances in nanofabrication technologies allowing the precise control of a nanostructure's pattern, periodicity, shape, and height have enabled a systematic study of cell interactions with three-dimensional nanotopographies. In this report, we examined the behavior of human foreskin fibroblasts on well-ordered dense arrays (post and grate patterns with a 230-nm pitch) of sharp-tip nanostructures with varying three-dimensionalities (from 50 to 600 nm in structural height) over time—until a cell sheet was formed. Although cells started out smaller and proliferated slower on tall nanostructures (both posts and grates) than on smooth surfaces, they became confluent to form a sheet in 3 weeks. On grate patterns, significant cell elongation in alignment with the underlying pattern was observed and maintained over time. On tall nanostructures, cells grew while raised on sharp tips, resulting in a weak total adherence to the solid surface. A sheet of cells was easily peeled off from such surfaces, suggesting that nanoscale topographies can be used as the basis for cell-sheet tissue engineering. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009
This paper introduces a novel recognition framework for human actions using hybrid features. The ... more This paper introduces a novel recognition framework for human actions using hybrid features. The hybrid features consist of spatio-temporal and local static features extracted using motion-selectivity attribute of 3D dual-tree complex wavelet transform (3D DT-CWT) and affine SIFT local image detector, respectively. The proposed model offers two core advantages: (1) the framework is significantly faster than traditional approaches due to volumetric processing of images as a '3D box of data' instead of a frame by frame analysis, (2) rich representation of human actions in terms of reduction in artifacts in view of the promising properties of our recently designed full symmetry complex filter banks with better directionality and shift-invariance properties. No assumptions about scene background, location, objects of interest, or point of view information are made whereas bidirectional two-dimensional PCA (2D-PCA) is employed for dimensionality reduction which offers enhanced capabilities to preserve structure and correlation amongst neighborhood pixels of a video frame.
A scintillation microprobe has been developed to directly measure the positron decay activity fro... more A scintillation microprobe has been developed to directly measure the positron decay activity from radiotracers in live animals. The probe consists of a small LSO crystal coupled to an optical fiber which is read out with a photomultiplier tube operated in a single photon counting mode. Positron conversions in the crystal are detected with high efficiency due to the excellent stopping power and high light output of LSO, and allows for the direct determination of the positron emitter concentration in a localized region of tissue. The probe can be used in the study of chemical kinetics and the development of new radiotracers in awake and freely moving animals
Journal of Neurophysiology, 2003
The subunit of the -aminobutyric acid (A) receptor (GABA A R) is expressed postnatally mostly in ... more The subunit of the -aminobutyric acid (A) receptor (GABA A R) is expressed postnatally mostly in the cerebellum, thalamus and dentate gyrus. Previous studies in mice with a targeted disruption of the subunit revealed a considerable attenuation of behavioral responses to neuroactive steroids, but not to other neuromodulatory drugs. Here we show that subunit loss leads to a concomitant reduction in hippocampal 4 subunit levels. These changes were accompanied by faster decay of evoked inhibitory postsynaptic potentials (IPSPs) in dentate granule neurons of -/-mutants (decay =25ms) compared to +/+ controls ( =50ms). Furthermore, the miniature GABA A R-mediated synaptic currents (mIPSCs) also decayed faster in -mutants ( =6.3ms) than controls ( =7.2ms), and had decreased frequency (controls, 10.5Hz; mutants, 6.6Hz). Prolongation of mIPSCs by the neuroactive steroid anesthetic, alphaxalone (1-10µM), was smaller in -mutants (at 10µM, 65% increase) compared to +/+ littermates (308% increase).
American Journal of Medical Genetics, 2002
Several lines of evidence suggest that the variable age at onset of Parkinson disease (PD) is lik... more Several lines of evidence suggest that the variable age at onset of Parkinson disease (PD) is likely influenced by genes. The apolipoprotein E (APOE) gene is associated with onset of Alzheimer disease, and possibly other neurodegenerative disorders. APOE has been investigated in relation to onset of PD, but results have been inconsistent. The aim of the present study was to determine if APOE genotypes are associated with onset age of PD, using a patient population large enough to assure sufficient power. We studied 521 unrelated Caucasian patients with idiopathic PD from movement disorder clinics in Oregon and Washington. Genotyping and statistical analyses were carried out using standard methods. Age at onset of PD was significantly earlier in patients with the ε3ε4/ε4ε4 genotype than in patients with the ε3ε3 genotype (56.1 ± 10.9 vs. 59.6 ± 11.0, P = 0.003). The significantly earlier onset of PD was not influenced by the possible effects of recruitment site, family history and gender. The effect of the ε2ε3 genotype on onset of PD differed between the two recruitment sites. There was a trend for earlier onset of PD in ε2ε3 patients than in ε3ε3 patients only in the Oregon sample. In conclusion, APOE is associated with age at onset of PD. © 2001 Wiley-Liss, Inc.
A hierarchical coder (HC) is constructed from a number of simple coders for image blocks arranged... more A hierarchical coder (HC) is constructed from a number of simple coders for image blocks arranged in order of increasing bit rate and reproduction quality. This paper discusses several aspects of hierarchical coders, including: a general description of the structure of a HC, its advantages and important design considerations, a discussion of how threshold selection can affect the performance of the coder through a simple example, and an introduction of a simple procedure for selecting optimal (in the rate distortion sense) decision thresholds which control the levels of the hierarchy
PLOS One, 2012
Neurotrophins (NTs) are a family of secreted growth factor proteins primarily involved in the reg... more Neurotrophins (NTs) are a family of secreted growth factor proteins primarily involved in the regulation of survival and appropriate development of neural cells, functioning by binding to their specific (TrkA, TtkB, and TrkC) and/or common NGFR receptor. NGFR is the common receptor of NTs, binding with low-affinity to all members of the family. Among different functions assigned to NGFR, it is also involved in apoptosis induction and tumorigenesis processes. Interestingly, some of the functions of NGFR appear to be ligand-independent, suggesting a probable involvement of non-coding RNA residing within the sequence of the gene. Here, we are reporting the existence of a conserved putative microRNA, named Hsa-mir-6165 [EBI accession#: FR873488]. Transfection of a DNA segment corresponding to the pre-mir-6165 sequence in Hela cell line caused the generation of mature exogenous mir-6165 (a ,200,000 fold overexpression). Furthermore, using specific primers, we succeeded to detect the endogenous expression of mir-6165 in several glioma cell lines and glioma primary tumors known to express NGFR. Similar to the pro-apoptotic role of NGFR in some cell types, overexpression of premir-6165 in U87 cell line resulted in an elevated rate of apoptosis. Moreover, coordinated with the increased level of mir-6165 in the transfected U87 cell line, two of its predicted target genes (Pkd1 and DAGLA) were significantly down-regulated. The latter findings suggest that some of the previously attributed functions of NGFR could be explained indirectly by cotranscription of mir-6165 in the cells.
Skull Base-an Interdisciplinary Approach, 2005
Cerebral revascularization continues to evolve as an option in the setting of ischemia. The poten... more Cerebral revascularization continues to evolve as an option in the setting of ischemia. The potential to favorably influence stroke risk and the natural history of cerebrovascular occlusive disease is being evaluated by the ongoing Carotid Occlusion Surgery Study and the Japanese Extracranial-Intracranial Bypass Trial. For those patients who undergo bypass in the setting of ischemia, four key areas of follow-up include functional neurological status, neurocognitive status, bypass patency, and status of cerebral blood flow and perfusion. Several stroke scales that can be used to assess functional status include the National Institutes of Health Stroke Scale, Bathel Index, Modified Rankin Scale, and Stroke Specific Quality of Life. Neurocognition can be checked using the Repeatable Battery for the Assessment of Neuropsychological Status, among other tests. Bypass patency is checked intraoperatively using various flow probes and postoperatively using magnetic resonance angiography (MRA) or computed tomographic angiography (CTA). Cerebral blood flow and perfusion can be assessed using a host of modalities that include positron emission tomography (PET), xenon CT, single photon emission computed tomography (SPECT), transcranial Doppler (TCD), CT, and MR. Paired blood flow studies after a cerebral vasodilatory stimulus using one of these modalities can determine the state of autoregulatory vasodilation (Stage 1 hemodynamic compromise). However, only PET with oxygen extraction fraction measurements can reliably assess for Stage 2 compromise (misery perfusion). This article discusses the various clinical, neuropsychological, and radiographic techniques available to assess a patient's clinical state and cerebral blood flow before and after cerebral revascularization.
This paper introduces a human actions recognition framework based on multiple types of features. ... more This paper introduces a human actions recognition framework based on multiple types of features. Taking the advantage of motion-selectivity property of 3D dual-tree complex wavelet transform (3D DT-CWT) and affine SIFT local image detector, firstly spatio-temporal and local static features are extracted. No assumptions of scene background, location, objects of interest, or point of view information are made whereas bidirectional two-dimensional PCA (2D-PCA) is employed for dimensionality reduction which offers enhanced capabilities to preserve structure and correlation amongst neighborhood pixels of a video frame. The proposed technique is significantly faster than traditional methods due to volumetric processing of input video, and offers a rich representation of human actions in terms of reduction in artifacts. Experimental examples are given to illustrate the effectiveness of the approach.
Pm&r
Objective: To evaluate the relationship between disability and both health-related quality of lif... more Objective: To evaluate the relationship between disability and both health-related quality of life (HRQoL) and caregiver burden in patients with upper limb poststroke spasticity.
BMC Proceedings, 2011
Introduction / objectivesWHO African Partnerships for Patient Safety (APPS) nurtures sustainable ... more Introduction / objectivesWHO African Partnerships for Patient Safety (APPS) nurtures sustainable partnerships between African and European hospitals to improve patient safety. Through APPS, Hôpitaux Universitaires de Genève (HUG) is partnered with hospitals in Cameroon, Mali and Senegal.MethodsHospital representatives convened in 2009 to build the programme foundation, followed by hospital situational analyses to determine priority action areas. Among 12 patient safety action areas, reduction of health care-associated infection (HAI) was chosen as a common platform of action. Subsequently, 2-year partnership action plans were developed, finalized at a workshop in 2009 in Uganda. Hand hygiene (HH), the single most effective measure to reduce HAI, was the cornerstone of planned action.ResultsA broad range of HH improvement tools was made available through a patient safety resource map. African technicians were trained on alcohol-based handrub production. An initial batch of materials was ...
Archives of Physical Medicine and Rehabilitation, 2006
Haghpanah S, Bogie K, Wang X, Banks PG, Ho CH. Reliability of electronic versus manual wound meas... more Haghpanah S, Bogie K, Wang X, Banks PG, Ho CH. Reliability of electronic versus manual wound measurement techniques. Arch Phys Med Rehabil 2006;87: 1396-402.
Journal of Biomedical Materials Research Part A, 2009
Cells in vivo encounter with and react to the extracellular matrix materials on a nanometer scale... more Cells in vivo encounter with and react to the extracellular matrix materials on a nanometer scale. Recent advances in nanofabrication technologies allowing the precise control of a nanostructure's pattern, periodicity, shape, and height have enabled a systematic study of cell interactions with three-dimensional nanotopographies. In this report, we examined the behavior of human foreskin fibroblasts on well-ordered dense arrays (post and grate patterns with a 230-nm pitch) of sharp-tip nanostructures with varying three-dimensionalities (from 50 to 600 nm in structural height) over time—until a cell sheet was formed. Although cells started out smaller and proliferated slower on tall nanostructures (both posts and grates) than on smooth surfaces, they became confluent to form a sheet in 3 weeks. On grate patterns, significant cell elongation in alignment with the underlying pattern was observed and maintained over time. On tall nanostructures, cells grew while raised on sharp tips, resulting in a weak total adherence to the solid surface. A sheet of cells was easily peeled off from such surfaces, suggesting that nanoscale topographies can be used as the basis for cell-sheet tissue engineering. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009
This paper introduces a novel recognition framework for human actions using hybrid features. The ... more This paper introduces a novel recognition framework for human actions using hybrid features. The hybrid features consist of spatio-temporal and local static features extracted using motion-selectivity attribute of 3D dual-tree complex wavelet transform (3D DT-CWT) and affine SIFT local image detector, respectively. The proposed model offers two core advantages: (1) the framework is significantly faster than traditional approaches due to volumetric processing of images as a '3D box of data' instead of a frame by frame analysis, (2) rich representation of human actions in terms of reduction in artifacts in view of the promising properties of our recently designed full symmetry complex filter banks with better directionality and shift-invariance properties. No assumptions about scene background, location, objects of interest, or point of view information are made whereas bidirectional two-dimensional PCA (2D-PCA) is employed for dimensionality reduction which offers enhanced capabilities to preserve structure and correlation amongst neighborhood pixels of a video frame.
A scintillation microprobe has been developed to directly measure the positron decay activity fro... more A scintillation microprobe has been developed to directly measure the positron decay activity from radiotracers in live animals. The probe consists of a small LSO crystal coupled to an optical fiber which is read out with a photomultiplier tube operated in a single photon counting mode. Positron conversions in the crystal are detected with high efficiency due to the excellent stopping power and high light output of LSO, and allows for the direct determination of the positron emitter concentration in a localized region of tissue. The probe can be used in the study of chemical kinetics and the development of new radiotracers in awake and freely moving animals
Journal of Neurophysiology, 2003
The subunit of the -aminobutyric acid (A) receptor (GABA A R) is expressed postnatally mostly in ... more The subunit of the -aminobutyric acid (A) receptor (GABA A R) is expressed postnatally mostly in the cerebellum, thalamus and dentate gyrus. Previous studies in mice with a targeted disruption of the subunit revealed a considerable attenuation of behavioral responses to neuroactive steroids, but not to other neuromodulatory drugs. Here we show that subunit loss leads to a concomitant reduction in hippocampal 4 subunit levels. These changes were accompanied by faster decay of evoked inhibitory postsynaptic potentials (IPSPs) in dentate granule neurons of -/-mutants (decay =25ms) compared to +/+ controls ( =50ms). Furthermore, the miniature GABA A R-mediated synaptic currents (mIPSCs) also decayed faster in -mutants ( =6.3ms) than controls ( =7.2ms), and had decreased frequency (controls, 10.5Hz; mutants, 6.6Hz). Prolongation of mIPSCs by the neuroactive steroid anesthetic, alphaxalone (1-10µM), was smaller in -mutants (at 10µM, 65% increase) compared to +/+ littermates (308% increase).
American Journal of Medical Genetics, 2002
Several lines of evidence suggest that the variable age at onset of Parkinson disease (PD) is lik... more Several lines of evidence suggest that the variable age at onset of Parkinson disease (PD) is likely influenced by genes. The apolipoprotein E (APOE) gene is associated with onset of Alzheimer disease, and possibly other neurodegenerative disorders. APOE has been investigated in relation to onset of PD, but results have been inconsistent. The aim of the present study was to determine if APOE genotypes are associated with onset age of PD, using a patient population large enough to assure sufficient power. We studied 521 unrelated Caucasian patients with idiopathic PD from movement disorder clinics in Oregon and Washington. Genotyping and statistical analyses were carried out using standard methods. Age at onset of PD was significantly earlier in patients with the ε3ε4/ε4ε4 genotype than in patients with the ε3ε3 genotype (56.1 ± 10.9 vs. 59.6 ± 11.0, P = 0.003). The significantly earlier onset of PD was not influenced by the possible effects of recruitment site, family history and gender. The effect of the ε2ε3 genotype on onset of PD differed between the two recruitment sites. There was a trend for earlier onset of PD in ε2ε3 patients than in ε3ε3 patients only in the Oregon sample. In conclusion, APOE is associated with age at onset of PD. © 2001 Wiley-Liss, Inc.
A hierarchical coder (HC) is constructed from a number of simple coders for image blocks arranged... more A hierarchical coder (HC) is constructed from a number of simple coders for image blocks arranged in order of increasing bit rate and reproduction quality. This paper discusses several aspects of hierarchical coders, including: a general description of the structure of a HC, its advantages and important design considerations, a discussion of how threshold selection can affect the performance of the coder through a simple example, and an introduction of a simple procedure for selecting optimal (in the rate distortion sense) decision thresholds which control the levels of the hierarchy