26 research outputs found
The human ankyrin 1 promoter insulator sustains gene expression in a β-globin lentiviral vector in hematopoietic stem cells.
Lentiviral vectors designed for the treatment of the hemoglobinopathies require the inclusion of regulatory and strong enhancer elements to achieve sufficient expression of the β-globin transgene. Despite the inclusion of these elements, the efficacy of these vectors may be limited by transgene silencing due to the genomic environment surrounding the integration site. Barrier insulators can be used to give more consistent expression and resist silencing even with lower vector copies. Here, the barrier activity of an insulator element from the human ankyrin-1 gene was analyzed in a lentiviral vector carrying an antisickling human β-globin gene. Inclusion of a single copy of the Ankyrin insulator did not affect viral titer, and improved the consistency of expression from the vector in murine erythroleukemia cells. The presence of the Ankyrin insulator element did not change transgene expression in human hematopoietic cells in short-term erythroid culture or in vivo in primary murine transplants. However, analysis in secondary recipients showed that the lentiviral vector with the Ankyrin element preserved transgene expression, whereas expression from the vector lacking the Ankyrin insulator decreased in secondary recipients. These studies demonstrate that the Ankyrin insulator may improve long-term β-globin expression in hematopoietic stem cells for gene therapy of hemoglobinopathies
External antenna design for GPS signal reception enhancement
The working paper explains the detailed analysis of the low-cost design and implementation of 53.0 × 41.0 mm Single Microstrip Patch Antenna (SMPA) for handheld Global Positioning System (GPS) receiver external use. A Computer Simulation Technology (CST) microwave studio technique was applied, using the dielectric of 5.0 and substrate thickness of 1.6 mm. The SMPA designed for data acquisition application operating on a single frequency on 1.57542 GHz. The antenna gain enhancement and the signal reception have improved the receiver line-of-sight (LOS) for an indoors experimental usage. However, the external antenna gain overcomes raw data quality degradation caused by the internal antenna due to low elevation angle and results in non LO
Images in Radiology - Intramedullary Tuberculoma of the Spinal Cord
A 36-year-old man presented with the complaints of intermittent fever
and paroxysms of dyspnoea. His chest X-ray film revealed apical changes
of the right lung and diffuse interstitial infiltration. The condition
was diagnosed as pulmonary tuberculosis and a course of quadruple
chemotherapy was begun. Three months after discharge, the patient was
referred to the neurosurgery clinic with the complaints of lower back
pain, bilateral leg pain and weakness. Neurological examination
revealed paraplegia, urinary incontinence and spastic reflexes.
Thoracic, cervical and lumbar X-rays were normal. Thoracic spinal
magnetic resonance imaging (MRI) revealed a circumscribed
intramedullary mass at the level of tenth thoracic vertebrae with a
hyperintense ring enhancement of the pia-arachnoid involving the whole
of the dorsal cord (Figures 1 and 2). The lesion was diagnosed as
intramedullary mass and high-dose steroids were consequently added to
the anti-tuberculosis therapy. Cerebral computed tomography was normal
Intramedullary tuberculoma of the spinal cord
A 36-year-old man presented with the complaints of intermittent fever
and paroxysms of dyspnoea. His chest X-ray film revealed apical changes
of the right lung and diffuse interstitial infiltration. The condition
was diagnosed as pulmonary tuberculosis and a course of quadruple
chemotherapy was begun. Three months after discharge, the patient was
referred to the neurosurgery clinic with the complaints of lower back
pain, bilateral leg pain and weakness. Neurological examination
revealed paraplegia, urinary incontinence and spastic reflexes.
Thoracic, cervical and lumbar X-rays were normal. Thoracic spinal
magnetic resonance imaging (MRI) revealed a circumscribed
intramedullary mass at the level of tenth thoracic vertebrae with a
hyperintense ring enhancement of the pia-arachnoid involving the whole
of the dorsal cord (Figures 1 and 2). The lesion was diagnosed as
intramedullary mass and high-dose steroids were consequently added to
the anti-tuberculosis therapy. Cerebral computed tomography was normal
Best Position Method for Experimental Data Acquisition Systems Using Low-cost GPS Receiver
Mobile satellites (MS) propagation is important
for the study of satellites signal strength. This paper concentrates
on the evaluation of best positioning for the experimental data
acquisition system, where a portable commercial Global
Positioning System receiver was used in getting the best position.
The receiver azimuth angle and elevation angle were utilized in
obtaining the best results. The experiment is carried out in an
open space area where line-of sight will be visible. Measurement
is then performed to determine the relationship between the
signal performance with respect to the elevation and azimuth
angles. The result obtained from this experiment will be used to
set a standard and best positioning for the GPS receiver in
collecting data for experimental purpose. Single frequency
receivers have the advantage that they are low-cost and CA-code
acquisition for civilian access provide higher signal to noise ratio
than synthesized P-code acquisition. Since the civilian users can
have only access of CA-code, while the P-code in mainly for
military users, this kind of receiver was used in this research.
Details methodology for doing the experimental works will be
discussed. The experiment was conducted at roof top of faculty of
engineering building, Universiti Malaysia Sarawak. Therefore, a
handheld GPS receiver best positioning experiment designed in
order to encourage more experimental works to be carried out in
the less developed countries. The analysis of the signal
performance under different MS environments is performed with
respect to the information such as elevation and azimuth angles
Honey prevents hepatic damage induced by obstruction of the common bile duct
AIM: To examine the possible effects of honey supplementation on hepatic damage due to obstruction of the common bile duct in an experimental rat model
Effects of strain rate and temperature on the mechanical behavior of high‐density polyethylene
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Enrichment of human hematopoietic stem/progenitor cells facilitates transduction for stem cell gene therapy.
Autologous hematopoietic stem cell (HSC) gene therapy for sickle cell disease has the potential to treat this illness without the major immunological complications associated with allogeneic transplantation. However, transduction efficiency by β-globin lentiviral vectors using CD34-enriched cell populations is suboptimal and large vector production batches may be needed for clinical trials. Transducing a cell population more enriched for HSC could greatly reduce vector needs and, potentially, increase transduction efficiency. CD34(+) /CD38(-) cells, comprising ∼1%-3% of all CD34(+) cells, were isolated from healthy cord blood CD34(+) cells by fluorescence-activated cell sorting and transduced with a lentiviral vector expressing an antisickling form of beta-globin (CCL-β(AS3) -FB). Isolated CD34(+) /CD38(-) cells were able to generate progeny over an extended period of long-term culture (LTC) compared to the CD34(+) cells and required up to 40-fold less vector for transduction compared to bulk CD34(+) preparations containing an equivalent number of CD34(+) /CD38(-) cells. Transduction of isolated CD34(+) /CD38(-) cells was comparable to CD34(+) cells measured by quantitative PCR at day 14 with reduced vector needs, and average vector copy/cell remained higher over time for LTC initiated from CD34(+) /38(-) cells. Following in vitro erythroid differentiation, HBBAS3 mRNA expression was similar in cultures derived from CD34(+) /CD38(-) cells or unfractionated CD34(+) cells. In vivo studies showed equivalent engraftment of transduced CD34(+) /CD38(-) cells when transplanted in competition with 100-fold more CD34(+) /CD38(+) cells. This work provides initial evidence for the beneficial effects from isolating human CD34(+) /CD38(-) cells to use significantly less vector and potentially improve transduction for HSC gene therapy
Enrichment of human hematopoietic stem/progenitor cells facilitates transduction for stem cell gene therapy.
Autologous hematopoietic stem cell (HSC) gene therapy for sickle cell disease has the potential to treat this illness without the major immunological complications associated with allogeneic transplantation. However, transduction efficiency by β-globin lentiviral vectors using CD34-enriched cell populations is suboptimal and large vector production batches may be needed for clinical trials. Transducing a cell population more enriched for HSC could greatly reduce vector needs and, potentially, increase transduction efficiency. CD34(+) /CD38(-) cells, comprising ∼1%-3% of all CD34(+) cells, were isolated from healthy cord blood CD34(+) cells by fluorescence-activated cell sorting and transduced with a lentiviral vector expressing an antisickling form of beta-globin (CCL-β(AS3) -FB). Isolated CD34(+) /CD38(-) cells were able to generate progeny over an extended period of long-term culture (LTC) compared to the CD34(+) cells and required up to 40-fold less vector for transduction compared to bulk CD34(+) preparations containing an equivalent number of CD34(+) /CD38(-) cells. Transduction of isolated CD34(+) /CD38(-) cells was comparable to CD34(+) cells measured by quantitative PCR at day 14 with reduced vector needs, and average vector copy/cell remained higher over time for LTC initiated from CD34(+) /38(-) cells. Following in vitro erythroid differentiation, HBBAS3 mRNA expression was similar in cultures derived from CD34(+) /CD38(-) cells or unfractionated CD34(+) cells. In vivo studies showed equivalent engraftment of transduced CD34(+) /CD38(-) cells when transplanted in competition with 100-fold more CD34(+) /CD38(+) cells. This work provides initial evidence for the beneficial effects from isolating human CD34(+) /CD38(-) cells to use significantly less vector and potentially improve transduction for HSC gene therapy