519 research outputs found

    Ionically cross-linked alginate hydrogels as drug delivery systems for analgesics in broiler chickens : thesis presented in partial fulfilment of the requirement for the degree of Masters of Science in Chemistry at Massey University, Palmerston North, Manawatu, New Zealand

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    Treating birds with analgesic drugs requires continuous injections of near lethal concentrations to maintain the therapeutic dose in the blood plasma. This is due to birds having higher metabolic rates than mammals. Therefore, there is a need to develop drug delivery systems that can control and slow down the release of analgesics in birds. This study was designed to analyse the sustained release of the model analgesics, sodium salicylate and sodium aspirin, from ionically cross-linked alginate hydrogels, in in vitro and in vivo experiments using broiler chickens as the model bird. Analgesic loaded hydrogels separated into two layers, unlike the homogeneous blank hydrogels. This was labelled as the separation effect. Swelling studies indicated the absence of the insoluble cross-linked alginate material in the hydrogels where the separation effect occurred, with most of the hydrogels dissolving back into the medium. The highest equilibrium swelling percentage achieved in the loaded hydrogels was 68 %. In comparison, the highest equilibrium swelling percentage in the blank hydrogels was 622 %. In vitro drug release profiles showed that the hydrogels released up to 100% of the sodium salicylate within 3.33 hours. In contrast, the hydrogels containing sodium aspirin released only 35 % of the encapsulated drug. Hydrogels containing a drug concentration of 150 mg/mL were injected into the model birds at a dose rate of 150 mg/Kg. No chicken reacted negatively to the hydrogel injection. In vivo results indicate sustained release of the model analgesic from the hydrogels compared to the release from the aqueous solutions of the drug. The effective concentration for an analgesic effect of sodium salicylate was maintained by the group injected with an aqueous solution of sodium salicylate 18 hours after the injection. The groups injected with the hydrogel with the maximum calcium chloride content saw the largest sustained release, with the plasma concentration of sodium salicylate remaining over the effective concentration for up to 36 hours after the injection. Keywords: Sodium salicylate, sodium aspirin, hydrogel, analgesia, sustained release, broiler chicken

    Analytical and computational methods for Two-phase flow with soluble surfactant

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    A hybrid method is used to determine the influence of surfactant solubility on two-phase flow by solution of a reduced transition layer equation near a fluid interface in the limit of large bulk Peclet number. The method is applied to finding the evolution of a drop of arbitrary viscosity that is deformed by an imposed linear strain or simple shear flow. A semi-analytical solution of the transition layer equation is given that expresses exchange of surfactant between its bulk and interfacial forms in terms of a convolution integral in time. Results of this semi-analytical solution are compared with the results of a spatially spectrally accurate numerical solution. Although both the hybrid method and its semi-analytical solution are valid in three dimensions, the two-dimensional context of this study allows additional validation of results by comparison with those of conformal mapping techniques applied to inviscid bubbles

    The relationship between job characteristics towards job satisfaction: a case study at Kuala Lumpur Airport Services Sdn. Bhd. / Nuraszalina Booty Asmara Booty

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    The most important element in an organization is about job satisfaction among workers. We can said that job satisfaction is the starting point in order to make sure the organization really success in their business. But, this key point always been unrealized by the organization because busy thinking on how to create more money and benefit day by day. The organization may achieve their target in business, but they will face a lot of problems if their workers feel unsatisfied with their job. As a result, the employees will create problems on employees’ productivity, absenteeism, turnover rates, as well as disciplinary problem. Kuala Lumpur Airport Services Sdn. Bhd. (KLAS) has about 1,400 employees and also faced the common problems. Even though KLAS have been provided all their employees with excellent benefits, some of the employees still feel unsatisfied with their job. Due to the important factor to the organization, that is why me as the researcher decided to know deeper and do research on the relationship between job characteristics (salary, reward, job stress, employee attitudes, teamwork) towards the level of job satisfaction. In this study of research, job characteristics act as independent variables, while job satisfaction act as dependent variable. The scope of study involves 50 of respondents and chooses non-probability as sampling technique. The questionnaire is divided into several sections. Furthermore, this studies using primary and secondary data. Findings are interpreted using several methods of analysis. As conclusion, there is a relationship between reward and Job Satisfaction. The recommendations that been recommended is to reconstruct the compensation packages, developing a service point, and, arrange the duty roaster not too tight

    GUCY2C lysosomotropic endocytosis delivers immunotoxin therapy to metastatic colorectal cancer.

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    The emergence of targeted cancer therapy has been limited by the paucity of determinants which are tumor-specific and generally associated with disease, and have cell dynamics which effectively deploy cytotoxic payloads. Guanylyl cyclase C (GUCY2C) may be ideal for targeting because it is normally expressed only in insulated barrier compartments, including intestine and brain, but over-expressed by systemic metastatic colorectal tumors. Here, we reveal that GUCY2C rapidly internalizes from the cell surface to lysosomes in intestinal and colorectal cancer cells. Endocytosis is independent of ligand binding and receptor activation, and is mediated by clathrin. This mechanism suggests a design for immunotoxins comprising a GUCY2C-directed monoclonal antibody conjugated through a reducible disulfide linkage to ricin A chain, which is activated to a potent cytotoxin in lysosomes. Indeed, this immunotoxin specifically killed GUCY2C-expressing colorectal cancer cells in a lysosomal- and clathrin-dependent fashion. Moreover, this immunotoxin reduced pulmonary tumors \u3e80% (

    Novel actions of next-generation taxanes benefit advanced stages of prostate cancer.

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    PURPOSE: To improve the outcomes of patients with castration-resistant prostate cancer (CRPC), there is an urgent need for more effective therapies and approaches that individualize specific treatments for patients with CRPC. These studies compared the novel taxane cabazitaxel with the previous generation docetaxel, and aimed to determine which tumors are most likely to respond. EXPERIMENTAL DESIGN: Cabazitaxel and docetaxel were compared via in vitro modeling to determine the molecular mechanism, biochemical and cell biologic impact, and cell proliferation, which was further assessed ex vivo in human tumor explants. Isogenic pairs of RB knockdown and control cells were interrogated in vitro and in xenograft tumors for cabazitaxel response. RESULTS: The data herein show that (i) cabazitaxel exerts stronger cytostatic and cytotoxic response compared with docetaxel, especially in CRPC; (ii) cabazitaxel induces aberrant mitosis, leading to pyknotic and multinucleated cells; (iii) taxanes do not act through the androgen receptor (AR); (iv) gene-expression profiling reveals distinct molecular actions for cabazitaxel; and (v) tumors that have progressed to castration resistance via loss of RB show enhanced sensitivity to cabazitaxel. CONCLUSIONS: Cabazitaxel not only induces improved cytostatic and cytotoxic effects, but also affects distinct molecular pathways, compared with docetaxel, which could underlie its efficacy after docetaxel treatment has failed in patients with CRPC. Finally, RB is identified as the first potential biomarker that could define the therapeutic response to taxanes in metastatic CRPC. This would suggest that loss of RB function induces sensitization to taxanes, which could benefit up to 50% of CRPC cases

    Paleopedology of the Late Triassic Middle Passaic Formation, Newark Supergroup, Pottstown, PA

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    Cyclic stratigraphy has been recognized in the Newark Basin for many years. Each package, referred to as a Van Houten Cycle (VHC), generally has three divisions: shallow lake, deep lake, and subaerial exposure. Van Houten (1964) first proposed that Milankovitch orbital forcing was responsible for the manifestation of these ~21 kyr cycles. Although root traces have been observed in VHCs by others, no detailed paleopedological analysis has been performed that examines the relationship between individual VHCs, orbital forcing, and paleosol development. The Middle Passaic Formation of Late Triassic age is continuously exposed for over 30 meters along a railroad cut that follows Manatawny Creek near Pottstown, PA. Six VHCs were identified at this location and the upper most three were selected for detailed study due to their strong development. Three Van Houten Groups (VHGs), consisting of VHC Division 3, Division 1, and Division 2 respectively, were formed in order to group paleosol profiles (Division 3) with stratigraphically adjacent lacustrine units (Divisions 1 and 2) since the lakes directly affect the paleosurface through inundation and erosion. Petrographic analysis suggests that soils in this section only developed to the degree of Entisols or Protosols. Voids are lined with chalcedony and cored with calcite indicating diagenetic alteration. Molecular weathering ratio calculations proved unreliable due to diagenetic alteration of the strata. Magnetic susceptibility was measured on two intervals of the section, but is not well-suited to fractured, massive rock due to signal attenuation. Paleosol development is greater in instances where the overlying lake is poorly developed. Paleosols that are associated with a shallow lake or no lake likely have more time to develop than paleosols associated with deep lakes as the precipitation filling the lake would saturate the soil, hindering pedogenesis. The VHCs' ~21 kyr interval forces time to be the limiting factor for pedogenesis in this section, ending in either sedimentation or inundation. However, time is also tied to climate as it modulates from relatively moist to relatively drier within a VHC. Orbital forcing is the ultimate controlling factor in soil formation since time, climate, insolation, and precipitation are all interrelated and influenced by it. Relief is independent of orbital forcing and a possible control on soil formation within the Basin. Soils that formed distal from the bounding fault may not have been subject to inundation due to their higher elevation. Further research is needed to establish paleocatenary relationships of soil within the Newark Basin.Geolog

    MATH 211-007: Calculus III A

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    MATH 211-013: Calculus III A

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    MATH 689-002: Adv Applied Math II

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