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Transdermal delivery of isoniazid and rifampicin by pheroid technology / Adèle BotesBotes, Adèle January 2007 (has links)
Thesis (M.Sc. (Pharmaceutics))--North-West University, Potchefstroom Campus, 2008.
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Modeling Molecular Transport and Binding Interactions in Intervertebral DiscTravascio, Francesco 10 December 2009 (has links)
Low back pain represents a significant concern in the United States, with 70% of individuals experiencing symptoms at some point in their lifetime. Although the specific cause of low back pain remains unclear, symptoms have been strongly associated with degeneration of the intervertebral disc. Insufficient nutritional supply to the disc is believed to be a major mechanism for tissue degeneration. Understanding nutrients' transport in intervertebral disc is crucial to elucidate the mechanisms of disc degeneration, and to develop strategies for tissue repair (in vivo), and tissue engineering (in vitro). Transport in intervertebral disc is complex and involves a series of electromechanical, chemical and biological coupled events. Despite of the large amount of studies performed in the past, transport phenomena in the disc are still poorly understood. This is partly due to the limited number of available experimental techniques for investigating transport properties, and the paucity of theoretical or numerical methods for systematically predicting the mechanisms of solute transport in intervertebral disc. In this dissertation, a theoretical and experimental approach was taken in order to investigate the mechanisms of solute transport and binding interactions in intervertebral disc. New imaging techniques were developed for the experimental determination of diffusive and binding parameters in biological tissues. The techniques are based on the principle of fluorescence recovery after photobleaching, and allow the determination of the anisotropic diffusion tensor, and the rates of binding and unbinding of a solute to the extracellular matrix of a biological tissue. When applied to the characterization of transport properties of intervertebral disc, these methods allowed the establishment of a relationship between solute anisotropic and inhomogeneous diffusivity and the unique morphology of human lumbar annulus fibrosus. A mixture theory for charged hydrated soft tissues was presented as a framework for theoretical investigations on solute transport and binding interactions in cartilaginous tissues. Based on this theoretical framework and on experimental observations, a finite element model was developed to predict solute diffusive-convective-reactive transport in cartilaginous tissues. The numerical model was applied to simulate the effect of mechanical loading on solute transport and binding interactions in cartilage explants and intervertebral disc.
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HelioScan : A software framework for controlling in vivo microscopy setups with high hardware flexibility, functional diversity and extendibilityLanger, Dominik, van 't Hoff, Marcel, Keller, Andreas J., Nagaraja, Chetan, Pfaeffli, Oliver A., Goeldi, Maurice, Kasper, Hansjoerg, Helmchen, Fritjof January 2013 (has links)
Intravital microscopy such as in vivo imaging of brain dynamics is often performed with custom-built microscope setups controlled by custom-written software to meet specific requirements. Continuous technological advancement in the field has created a need for new control software that is flexible enough to support the biological researcher with innovative imaging techniques and provide the developer with a solid platform for quickly and easily implementing new extensions. Here, we introduce HelioScan, a software package written in LabVIEW, as a platform serving this dual role. HelioScan is designed as a collection of components that can be flexibly assembled into microscope control software tailored to the particular hardware and functionality requirements. Moreover, HelioScan provides a software framework, within which new functionality can be implemented in a quick and structured manner. A specific HelioScan application assembles at run-time from individual software components, based on user-definable configuration files. Due to its component-based architecture, HelioScan can exploit synergies of multiple developers working in parallel on different components in a community effort. We exemplify the capabilities and versatility of HelioScan by demonstrating several in vivo brain imaging modes, including camera-based intrinsic optical signal imaging for functional mapping of cortical areas, standard two-photon laser-scanning microscopy using galvanometric mirrors, and high-speed in vivo two-photon calcium imaging using either acousto-optic deflectors or a resonant scanner. We recommend HelioScan as a convenient software framework for the in vivo imaging community. / <p>Paid Open Access</p>
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Protein sorption to contact lenses and intraocular lensesLuensmann, Doerte January 2009 (has links)
Purpose:
To locate protein sorption on the surface and inside the matrix of soft contact lens materials and intraocular lenses (IOL).
Methods:
The proteins albumin and lysozyme were investigated as they are highly abundant in blood serum and tears, respectively. Proteins were conjugated with organic fluorescent probes and using confocal laser scanning microscopy (CLSM) the sorption profile to contact lenses and IOL could be determined. Radiolabeled protein was used for quantification purposes.
• Albumin sorption to etafilcon A and lotrafilcon B was determined (Chapter 3)
• Different fluorescent probes were used for conjugation and the impact on albumin sorption behaviour was investigated (Chapter 4)
• Lysozyme sorption to nine different pHEMA-based and silicone hydrogel contact lenses was determined using two fluorescent probes (Chapter 5)
• The efficiency of protein removal from contact lenses using contact lens care regimens was investigated (Chapter 6)
• Albumin sorption to IOL materials was quantified and imaged using a modified CLSM technique (Chapter 7)
Results:
Albumin and lysozyme sorption profiles differed between materials, and were influenced by the fluorescent probes used for conjugation. After one day of incubation, both proteins could be located within all contact lens materials, except for lotrafilcon A and lotrafilcon B, which primarily allowed deposition on the lens surface. An increase in protein accumulation was found for most materials over the maximum investigated period of 14 days, using CLSM and radiolabel techniques. The efficiency of contact lens care regimens to remove lysozyme and albumin depended on the lens material, care regimen and protein type investigated.
PMMA and silicone IOLs showed protein exclusively on the surface, while a hydrophilic acrylic IOL allowed penetration into the lens matrix over time. Despite the albumin penetration depth into hydrophilic acrylic, the highest albumin levels were determined for the silicone IOL.
Conclusions:
CLSM provides detailed information that can describe the protein distribution in transparent biomaterials, with scanning depths up to a few hundred microns. However, the CLSM data are primarily of qualitative value, which necessitates a quantitative technique (e.g. radiolabeling) to determine the total protein content.
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Protein sorption to contact lenses and intraocular lensesLuensmann, Doerte January 2009 (has links)
Purpose:
To locate protein sorption on the surface and inside the matrix of soft contact lens materials and intraocular lenses (IOL).
Methods:
The proteins albumin and lysozyme were investigated as they are highly abundant in blood serum and tears, respectively. Proteins were conjugated with organic fluorescent probes and using confocal laser scanning microscopy (CLSM) the sorption profile to contact lenses and IOL could be determined. Radiolabeled protein was used for quantification purposes.
• Albumin sorption to etafilcon A and lotrafilcon B was determined (Chapter 3)
• Different fluorescent probes were used for conjugation and the impact on albumin sorption behaviour was investigated (Chapter 4)
• Lysozyme sorption to nine different pHEMA-based and silicone hydrogel contact lenses was determined using two fluorescent probes (Chapter 5)
• The efficiency of protein removal from contact lenses using contact lens care regimens was investigated (Chapter 6)
• Albumin sorption to IOL materials was quantified and imaged using a modified CLSM technique (Chapter 7)
Results:
Albumin and lysozyme sorption profiles differed between materials, and were influenced by the fluorescent probes used for conjugation. After one day of incubation, both proteins could be located within all contact lens materials, except for lotrafilcon A and lotrafilcon B, which primarily allowed deposition on the lens surface. An increase in protein accumulation was found for most materials over the maximum investigated period of 14 days, using CLSM and radiolabel techniques. The efficiency of contact lens care regimens to remove lysozyme and albumin depended on the lens material, care regimen and protein type investigated.
PMMA and silicone IOLs showed protein exclusively on the surface, while a hydrophilic acrylic IOL allowed penetration into the lens matrix over time. Despite the albumin penetration depth into hydrophilic acrylic, the highest albumin levels were determined for the silicone IOL.
Conclusions:
CLSM provides detailed information that can describe the protein distribution in transparent biomaterials, with scanning depths up to a few hundred microns. However, the CLSM data are primarily of qualitative value, which necessitates a quantitative technique (e.g. radiolabeling) to determine the total protein content.
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Wetting Performance of Worn Superhydrophobic SurfacesSingh, Maninderjit Unknown Date
No description available.
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Transdermal delivery of isoniazid and rifampicin by pheroid technology / Adèle BotesBotes, Adèle January 2007 (has links)
The aim of this in vitro study was to investigate the feasibility of the transdermal
delivery of isoniazid (INH) and rifampicin (RMP) by means of the novel PheroidTM
technology system. 'The application of the latter is being investigated in combination
with various actives such as peptides (insulin, human growth hormone), anti-malarial
drugs (chloroquine), anti-fungals (ketoconazole), local anaesthetics (lidocaine,
prilocaine) as well as tuberculostatics (ethambutol, pyrazinamide etc.) via different
administration routes at the North- West University.
PheroidTM, a stable skin-friendly carrier, comprises of a submicron (200 nm - 2 m)
emulsion type formulation for which previous studies have confirmed the ability to
penetrate keratinised tissue, skin, intestinal linings, the vascular system, fungi,
bacteria and even parasites. Studies involving an oral PheroidTM formulation
containing the current approved regime of four anti-tuberculosis drugs showed
improved efficacy results whilst an in vitro analysis of bacterial growth indicated a
reduction in drug resistance in multidrug resistant tuberculosis (MDR-TB) strains.
Therefore we thought it prudent to ascertain whether or not the PheroidTM system
would be able to improve the transdermal delivery of a combination of INH and RMP
as a possible treatment against cutaneous tuberculosis (tuberculosis involving the
skin). The latter refers to pathological lesions of the skin caused by any one of the
following: Mycobacterium tuberculosis, Mycobacterium bovis or the bacilli Calmette-
Guerin (BCG) vaccine. Demonstration of M. tuberculosis within the infected tissues
by traditional acid-fast bacilli (AFB) staining, culture or polymerase chain reaction
(PCR) confirms the diagnosis. CTB lesions are associated with various degrees of
one or more of the following ulceration, plaque formation, hyperkeratosis or the
presence of necrotic matter.
Seeing as C-TB is mostly associated with systemic involvement, current treatment
comprises of the standard three/four drug regimens used for pulmonary 'TB in
general. Cases of CTB usually show improvement within 1 month of therapy with
anti-TB drugs, but complete resolution is only attained after 4 - 6 months. 'The major
drawback to current therapy is that patients not only remain a source of infection
(viable organisms can still be demonstrated in the lesions), but they also suffer from constant embarrassment due to the disfiguring nature of CTB until these lesions have
healed completely. No evidence of an already existing topical formulation of this kind
could be found.
Therefore in vitro permeation studies were conducted using vertical Franz diffusion
cells and female abdominal skin as permeation membrane over a period of 12 hours.
Concentrations of 5 mg/ml and 10 mg/ml for isoniazid( INH) and rifampicin (RMP)
respectively, were applied to the donor phase suspended in either phosphate
buffered saline (PBS) or entrapped in PheroidTM. Permeation studies were
conducted at pH 5.5. In vitro penetration of INH and RMP were assayed directly by
HPLC. Particle size distribution for rifampicin and entrapment of actives within the
PheroidTM carrier system was determined by polarized light and laser scanning
microscopy (CLSM) respectively and revealed definite entrapment.
Permeation profiles obtained for INH in PheroidTM indicated a biphasic character,
whilst that obtained for RMP in PheroidTM showed a triphasic character. The
PheroidTM delivery system proved more efficacious for delivery of both anti-tubercular
drugs and resulted in greater percentage yield as well as flux values than that for a
PBS solution. Furthermore, the PheroidTM formulation was able to deliver, the
entrapped INH and RMP in concentrations sufficient to exceed their respective
minimum inhibitory concentrations (MIC). / Thesis (M.Sc. (Pharmaceutics))--North-West University, Potchefstroom Campus, 2008.
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Transdermal delivery of isoniazid and rifampicin by pheroid technology / Adèle BotesBotes, Adèle January 2007 (has links)
The aim of this in vitro study was to investigate the feasibility of the transdermal
delivery of isoniazid (INH) and rifampicin (RMP) by means of the novel PheroidTM
technology system. 'The application of the latter is being investigated in combination
with various actives such as peptides (insulin, human growth hormone), anti-malarial
drugs (chloroquine), anti-fungals (ketoconazole), local anaesthetics (lidocaine,
prilocaine) as well as tuberculostatics (ethambutol, pyrazinamide etc.) via different
administration routes at the North- West University.
PheroidTM, a stable skin-friendly carrier, comprises of a submicron (200 nm - 2 m)
emulsion type formulation for which previous studies have confirmed the ability to
penetrate keratinised tissue, skin, intestinal linings, the vascular system, fungi,
bacteria and even parasites. Studies involving an oral PheroidTM formulation
containing the current approved regime of four anti-tuberculosis drugs showed
improved efficacy results whilst an in vitro analysis of bacterial growth indicated a
reduction in drug resistance in multidrug resistant tuberculosis (MDR-TB) strains.
Therefore we thought it prudent to ascertain whether or not the PheroidTM system
would be able to improve the transdermal delivery of a combination of INH and RMP
as a possible treatment against cutaneous tuberculosis (tuberculosis involving the
skin). The latter refers to pathological lesions of the skin caused by any one of the
following: Mycobacterium tuberculosis, Mycobacterium bovis or the bacilli Calmette-
Guerin (BCG) vaccine. Demonstration of M. tuberculosis within the infected tissues
by traditional acid-fast bacilli (AFB) staining, culture or polymerase chain reaction
(PCR) confirms the diagnosis. CTB lesions are associated with various degrees of
one or more of the following ulceration, plaque formation, hyperkeratosis or the
presence of necrotic matter.
Seeing as C-TB is mostly associated with systemic involvement, current treatment
comprises of the standard three/four drug regimens used for pulmonary 'TB in
general. Cases of CTB usually show improvement within 1 month of therapy with
anti-TB drugs, but complete resolution is only attained after 4 - 6 months. 'The major
drawback to current therapy is that patients not only remain a source of infection
(viable organisms can still be demonstrated in the lesions), but they also suffer from constant embarrassment due to the disfiguring nature of CTB until these lesions have
healed completely. No evidence of an already existing topical formulation of this kind
could be found.
Therefore in vitro permeation studies were conducted using vertical Franz diffusion
cells and female abdominal skin as permeation membrane over a period of 12 hours.
Concentrations of 5 mg/ml and 10 mg/ml for isoniazid( INH) and rifampicin (RMP)
respectively, were applied to the donor phase suspended in either phosphate
buffered saline (PBS) or entrapped in PheroidTM. Permeation studies were
conducted at pH 5.5. In vitro penetration of INH and RMP were assayed directly by
HPLC. Particle size distribution for rifampicin and entrapment of actives within the
PheroidTM carrier system was determined by polarized light and laser scanning
microscopy (CLSM) respectively and revealed definite entrapment.
Permeation profiles obtained for INH in PheroidTM indicated a biphasic character,
whilst that obtained for RMP in PheroidTM showed a triphasic character. The
PheroidTM delivery system proved more efficacious for delivery of both anti-tubercular
drugs and resulted in greater percentage yield as well as flux values than that for a
PBS solution. Furthermore, the PheroidTM formulation was able to deliver, the
entrapped INH and RMP in concentrations sufficient to exceed their respective
minimum inhibitory concentrations (MIC). / Thesis (M.Sc. (Pharmaceutics))--North-West University, Potchefstroom Campus, 2008.
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Effect of Oxygen Partial Pressure and COD Loading on Biofilm Performance in a Membrane Aerated BioreactorZhu, Ivan Xuetang 28 July 2008 (has links)
The membrane aerated bioreactor (MABR) is a unique technological innovation where a gas permeable membrane is applied to biological processes. In an MABR, oxygen and other substrates diffuse from the opposite directions into a biofilm, and thus simultaneous chemical oxygen demand (COD) and nitrogen removal can be achieved. However, controlling biofilm thickness, stability, and attachment is challenging. The objectives of this research were to study the effect of oxygen partial pressure on process performance with respect to nitrogen removal and examine the biomass properties in MABRs at different oxygen partial pressures and COD loadings. The conditions within the bioreactors were based on a low hydrodynamic condition (average fluid velocity 22 cm/min along the membrane surface), with the intention of minimizing the impact of the hydrodynamic shear on biomass properties. Simultaneous nitrification and denitrification were achieved in the reactors, and increasing oxygen partial pressure enhanced the total nitrogen removal. The biomass at the membrane-biofilm interface was more porous at a loading of 11.3 kg COD/1000 m2/day (areal porosity about 0.9) as compared with a loading of 22.6 kg COD/1000 m2/day (areal porosity about 0.7), indicating carbon substrate was limiting near the membrane. Long-term (over 30 days) experimental results showed that at the loading of 11.3 kg COD/1000 m2/day, the oxygen partial pressures of 0.59 atm and 0.88 atm caused over 80% of the biomass to become suspended in the bulk phase while at 0.25 atm and 0.41 atm oxygen over 97% of the biomass was immobilized on the membrane. There is a critical oxygen partial pressure that can sustain the biofilm, which increases with an increasing COD loading. The nitrifying population in the reactors was examined by applying fluorescence in situ hybridization (FISH). At the loading of 22.6 kg COD/1000 m2/day, there were 12% beta-proteobacterial ammonia oxidizing bacteria (AOB) and 17%Nitrobacter in homogenized biofilm biomass at 0.59 atm oxygen while there were 7% beta-proteobacterial AOB and 4% Nitrobacter at 0.25 atm oxygen. The ratio of protein to carbohydrate in extracellular polymeric substances (EPS) of the homogenized biomass in the reactor decreased with increasing oxygen partial pressure. Surface characterization of the biomass revealed that the higher the oxygen partial pressure, the lower the biomass hydrophobicity and surface charge. The ratio of EPS protein to carbohydrate in a membrane aerated biofilm decreased when approaching the membrane-biofilm interface. The distribution of nitrifiers and dissolved oxygen profiles inside the biofilm suggested that dual substrate limitations exist, and it was concluded that the membrane aerated biofilm had an aerobic region in the inner layer and an anoxic region in the outer layer. It is proposed that the loss of EPS due to secondary substrate consumption, especially the loss of EPS proteins, at the bottom of the biofilm was responsible for biofilm detachment subjected to a critical oxygen partial pressure.
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Cayaponia silva manso (cucurbitaceae juss.), no estado de Goiás: uma abordagem morfológica e anatômica / Cayaponia silva manso (cucurbitaceae juss.), in the state of Goiás: a morphological and anatomical approachCardoso Junior, Ilvan Martins 31 March 2017 (has links)
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Previous issue date: 2017-03-31 / Fundação de Amparo à Pesquisa do Estado de Goiás - FAPEG / Cayaponia Silva Manso (Cucurbitaceae Juss.), In the State of Goiás: a morphological and anatomical approach - Cayaponia Silva Manso comprises about 60 species of which 47 occur in Brazil. Several studies have been carried out with species of this genus in view of the proven pharmacological potential for some taxa, mainly C. tayuya (Vell) Cogn., C. martiana (Cogn.) Cogn. In Goiás it was reported the existence of seven species that constitute two groups that are differentiated respectively by the habits and habitats where they are found, one formed by the species C. espelina (Silva Manso) Cogn., C. rugosa Gomes-Klein et Pirani and C. weddellii (Naudin) Cogn. And the other group comprising the species C. tayuya (Vell.) Cogn., C. citrullifolia (Griseb.) Cogn., C. diversifolia (Cogn.) Cogn. and C. podantha Cogn. Some studies have been carried out to solve complexes in other botanical families. Studies on the anatomy of vegetative and reproductive organs have presented results that contribute to a better circumscription for the species under study. In this work, morphological, taxonomic and anatomical studies were carried out with the objective of adding new information that allows a better delimitation and recognition of the studied species. A preliminary survey of information on Cayaponia species occurred in the State of Goiás. 41 expeditions were carried out in 42 municipalities. Specimens of 7 species were collected in the State of Goiás. For the morphological and taxonomic studies, the collected material was processed, herborized and identified according to the usual methodology. For the anatomical analysis part of the material was preserved fresh in a freezer at 10 ° C, another part fixed in alcohol70, in FAA70 or FPA70. In Chapter 1 the taxonomic treatment for the species occurring in Goiás was carried out. A key of identification, morphological and taxonomic description was presented, as well as illustrations of the species studied. In Chapter 2 the description of foliar architecture of the species under study was presented. Also in this chapter an identification key was developed for the species under study based on foliar architecture and venation patterns. Chapter 3 presents anatomical analyzes of petiole and leaf blade, scanning electron microscopy and histochemical tests that were used in the separation of taxa. Statistical tests, Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA) were applied with the objective of performing a prospection of morpho-anatomic characters that support the groups delimited in previous chapters. / Cayaponia Silva Manso (Cucurbitaceae Juss.), no Estado de Goiás: uma abordagem morfológica e anatômica - Cayaponia Silva Manso compreende em torno de 60 espécies das quais 47 ocorrem no Brasil. Diversos estudos tem sido realizados com espécies deste gênero tendo em vista o potencial farmacêutico comprovado para alguns taxa, principalmente C. tayuya (Vell) Cogn., C. martiana (Cogn.) Cogn. Em Goiás foi relatado a existência de sete espécies que constituem dois grupos que são diferenciados respectivamente pelos hábitos e habitats onde são encontrados, um formado pelas espécies C. espelina (Silva Manso) Cogn., C. rugosa Gomes-Klein et Pirani e C. weddellii (Naudin) Cogn. e o outro grupo compreendendo as espécies C. tayuya (Vell.) Cogn., C. citrullifolia (Griseb.) Cogn. e C. diversifolia (Cogn.) Cogn. e C. podantha Cogn. Alguns estudos tem sido realizados para solução de complexos em outras famílias botânicas. Trabalhos sobre anatomia de órgãos vegetativos e reprodutivos têm apresentado resultados que contribuem com uma melhor circunscrição para as espécies em estudo. Neste trabalho, foram realizados estudos morfológicos, taxonômicos e anatômicos com o objetivo de acrescentar novas informações que permitam melhor delimitação e reconhecimento das espécies estudadas. Foi realizado o levantamento prévio de informações sobre as espécies Cayaponia, ocorrentes no Estado de Goiás. Procedeu-se 41 expedições a 42 municípios. Foram coletados exemplares de 7 espécies ocorrentes no Estado de Goiás. Para os estudos morfológicos e taxonômicos o material coletado, foi processado, herborizado e identificado segundo metodologia usual. Para as análises anatômicas parte do material foi preservado fresco em freezer a 10°C, outra parte fixado em álcool70, em FAA70 ou FPA70. No Capítulo 1 foi realizado o tratamento taxonômico para as espécies ocorrentes em Goiás. Foi apresentada uma chave de identificação, descrição morfológica e taxonômica, além de ilustrações das espécies estudadas. No Capítulo 2 foi apresentada a descrição de arquitetura foliar das espécies em estudo. Ainda nesse capítulo foi elaborada uma chave de identificação para as espécies em estudo baseada na arquitetura foliar e padrões de venação. O Capítulo 3 apresenta análises anatômicas de pecíolo e lâmina foliar, microscopia eletrônica de varredura e testes histoquímicos que foram empregados na separação dos taxa. Testes estatísticos, análise de Componentes Principais (PCA, em inglês) e Análise Hierárquica de Cluster (HCA), foram aplicados com o objetivo de realizar uma prospecção de caracteres morfoanatômicos que suportam os grupos delimitados nos capítulos anteriores.
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