Abstract: This invention relates to a coded aperture mask for use in diagnostic nuclear medicine imaging. The coded aperture mask consists of a sheet of radiation opaque mask material having a series of apertures extending therethrough. The thickness of mask material has an attenuation percentage of less than 75% and, in a preferred embodiment, about equal to 29%. The coded aperture mask also, in a preferred embodiment, has a lead attenuation tube and has a projection of the smallest hole occupying the same area as a single pixel of a detector. The invention extends to a diagnostic nuclear medicine imaging system which uses a 16 bit gamma camera as a radiation detector.
Type:
Application
Filed:
May 22, 2008
Publication date:
August 4, 2011
Applicant:
UNIVERSITY OF THE WITWATERSRAND, JOHANNESBURG
Inventors:
Tshilidizi Marwala, David Milton Rubin, David Mark Starfield
Abstract: This invention relates to a polyamide rate-modulated monolithic drug delivery system comprising at least one active compound and a biodegradable and biocompatible polyamide polymer. The polymer is selected for delivering, in use, the active compound, within a predetermined time frame depending on the biodegradable properties of the polymer, to a target organism or organisms. In one embodiment of the invention the polymer is modified by salting-out or crosslinking the polymeric material to achieve the desired biodegradability characteristics and, consequently, to control the release of the active compound.
Type:
Application
Filed:
February 22, 2008
Publication date:
December 23, 2010
Applicant:
UNIVERSITY OF THE WITWATERSRAND, JOHANNESBURG
Abstract: This invention relates to a bioreactor for producing high rates of hydrogen from plant biomass. It also relates to the rapid screening, selection and isolation of biofilm forming mesophilic and/or thermophilic bacteria or bacteria consortia that generate high levels of hydrogen from plant biomass or from soluble hydrolysates derived from the hydrolysis of cellulosic materials including hemicellulose. The reactor comprises a primary reactor vessel having a bed of hydrogen producing bacteria towards its base located within a secondary reactor vessel which functions as a hydrogen gas collector and as a clarifier and separator. The plant biomass may be one or a mixture of insoluble cellulosic material and a hydrolysate derived from hydrolysis of cellulosic material. In one embodiment the bed of the primary reactor vessel is fluidised by recycling hydrogen gas saturated plant biomass effluent from the secondary reactor vessel to the primary reactor vessel.
Type:
Application
Filed:
September 9, 2008
Publication date:
December 2, 2010
Applicant:
UNIVERSITY OF THE WITWATERSRAND, JOHANNESBURG
Abstract: This invention relates to an improved monolithic drug delivery dosage form which releases a pharmaceutically active agent at a predetermined rate. The dosage form comprises a salted-out or crosslinked polymer and a pharmaceutically active agent. The salted-out or crosslinked polymer functions to polymerically entangle the pharmaceutically active agent but, progressively relax on contact with an aqueous medium in use to release the pharmaceutically active agent at a predetermined rate.
Type:
Application
Filed:
February 22, 2008
Publication date:
March 18, 2010
Applicant:
UNIVERSITY OF THE WITWATERSRAND, JOHANNESBURG
Abstract: The invention provides an assay for diagnosing and/or monitoring a viral infection or disease in a patient, the assay including the steps of mixing a sample of leucocytes with a fluorescent cell membrane-permeable dye which stains RNA or both DNA and RNA within the leucocytes; identifying from all the leucocytes at least two of the three major sub-populations of leucoytes selected from the group consisting of monocytes, granulocytes and lymphocytes; determining the fluorescence intensity for each of the identified sub-populations; and comparing the fluorescence intensity of at least two cell sub-populations to each other to obtain at least one of the following ratios: monocytes:granulocytes, monocytes:lymphocytes, and granulocytes lymphocytes. The viral infection may be HIV and the disease may be AIDS. The invention also provides a method of monitoring the cellular viral, parasitic or bacterial reservoir of a patient with a viral or bacterial infection by the steps described above.
Abstract: This invention relates to a pharmaceutical composition for mammals and, more particularly, to a pharmaceutical composition which enhances the action of an anaesthetic used in both human and veterinary applications, which, at least partly, reduces the risk of respiratory depression and enhances pulmonary perfusion. The pharmaceutical composition is characterised in that it contains a serotonergic ligand or any pharmacologically acceptable salt or ester thereof which acts on at least one member of the 5-HT family of serotonergic receptors, preferably on one or more of the 5-HTiA, 5-HT4 and 5-HT7 serotonergic receptors. In an example the ligand is the 8-OH-DPAT ligand. The composition can be used in conjunction with or include an anaesthetic, preferably an opioid anaesthetic, to induce a state of anaesthesia in mammals and it can be used to immobilise wile or non-domestic mammals.
Type:
Application
Filed:
September 14, 2006
Publication date:
August 13, 2009
Applicant:
UNIVERSITY OF THE WITWATERSRAND, JOHANNESBURG
Abstract: This invention relates to a method and an apparatus, primarily a radiation imaging apparatus and an array of coded aperture masks, for use in diagnostic nuclear medicine. The coded aperture masks are fitted with radiation attenuation tubes, each of which extends from each side of the mask in the direction of the mask apertures. The tubes are made from lead and have parallel sides. The masks are configured for gamma ray usage and are made from tungsten having a thickness of between 1 and 2 mm.
Type:
Application
Filed:
November 2, 2006
Publication date:
December 4, 2008
Applicant:
UNIVERSITY OF THE WITWATERSRAND, JOHANNESBURG
Inventors:
David Mark Starfield, David Milton Rubin, Tshilidzi Marwala
Abstract: The invention provides a process for producing carbon nanotubes which includes supplying a continuous fluidized feed of a catalyst and at least one hydrocarbon to a reactor operating under conditions suitable to produce carbon nanotubes. The fluid is made to flow though the reactor with a swirling motion which ensures that the internal surfaces of the reactor are cleaned of deposits.
Type:
Application
Filed:
August 29, 2006
Publication date:
October 9, 2008
Applicant:
UNIVERSITY OF THE WITWATERSRAND, JOHANNESBURG