<p>Everyday thousands of nurses are rendering bedside nursing care in health care settings as a result they are exposed to blood, body fluids and sharp objects that are contaminated with Hepatitis B, Hepatitis C and HIV. Therefore they are at risk of getting infected. In 1996, standard precautions were implemented by the Centre of Disease Control to reduce the risk of transmission of micro-organisms from any source of infection in the hospital. In the year 2008, the three tertiary hospitals together in the Western Cape reported that they had 733 needle prick injuries. Therefore the aim of the study was to determine if nurses comply with and have adequate knowledge of standard precautions. A non-experimental design and a self administered questionnaire were used to collect the data for the study. The study was done at Tygerberg Hospital and the participants (n=143) that were involved in the study were all nursing categories (professional, enrolled nurse and auxiliary nurse). Stratified random sampling was used to ensure that there was a representation of all the nurses working in the different modules at Tygerberg Hospital. Therefore three wards were randomly selected from each module and all the nurses on duty working in the three selected wards were given a questionnaire by the Assistant Director of the specific module. After the data was collected it was analysed through the statistical package for social sciences. The findings of the study showed that nurses have inadequate knowledge regarding standard precautions and the mean score of the nurses overall self reported compliance of standard precautions was 87.5%. The results also showed that when patients are HIV positive nurses intend to over comply the use of personal protective equipment. No association was found between the nurses&rsquo / knowledge and compliance regarding standard precautions. It is therefore important that every nurse should be educated about the basic principles of standard precautions and also the policies and protocols of infection control in order to prevent each nurse from getting infected. Training needs to be implemented starting in the wards through the unit manager to improve all the nurses&rsquo / knowledge and practice.</p>

O estudo trata de acidentes com material biológico que ocorreram com os profissionais de saúde, no Hospital de Clínicas de Porto Alegre (HCPA), no período de janeiro de 2006 a dezembro de 2011. Um estudo observacional retrospectivo que objetivou caracterizar a frequência de ocorrência de acidentes ocupacional determinando a exposição a material biológico entre profissionais de saúde. Foram analisados 1.283 acidentes formalmente registrados pelo Serviço de Medicina Ocupacional do HCPA entre janeiro de 2006 a dezembro de 2011. Foi possível constatar a predominância de acidentes com materiais perfurocortantes (80%) dentre todos os acidentes com material biológico registrados no estudo ao longo de 6 anos. Verificou-se que os técnicos de enfermagem e os médicos residentes foram os profissionais que mais se acidentaram. Com relação ao comportamento dos acidentes ao logo destes 6 anos, a análise da série temporal evidenciou que houve uma tendência de aumento dos acidentes com material biológico entre os médicos residentes. Já com os demais profissionais de saúde, a série temporal apresentou-se estacionária. / The study comes to accidents with biological material that occurred with health professionals, Hospital de Clinicas de Porto Alegre (HCPA), from January 2006 to December 2011. A retrospective observational study aimed to characterize the frequency of accidents determining occupational exposure to biological material among health professionals. The study analysed 1,283 formally registered by the Occupational Medicine Department of the institution between January 2006 to December 2011. It was possible to observe the prevalence of accidents with sharps (80%) of all accidents with biological material recorded in the study just 6 years. It was found that the nursing staff and the residents were professionals who were hurt more. With respect to the behavior of these accidents the logo six years, the analysis of time series showed that there was an increasing trend of accidents with biological material among medical residents. Already with other health professionals, the series presented stationary.

Magister Curationis - MCur / Everyday thousands of nurses are rendering bedside nursing care in health care settings as a result they are exposed to blood, body fluids and sharp objects that are contaminated with Hepatitis B, Hepatitis C and HIV. Therefore they are at risk of getting infected. In 1996, standard precautions were implemented by the Centre of Disease Control to reduce the risk of transmission of micro-organisms from any source of infection in the hospital. In the year 2008, the three tertiary hospitals together in the Western Cape reported that they had 733 needle prick injuries. Therefore the aim of the study was to determine if nurses comply with and have adequate knowledge of standard precautions. A non-experimental design and a self administered questionnaire were used to collect the data for the study. The study was done at Tygerberg Hospital and the participants (n=143) that were involved in the study were all nursing categories (professional, enrolled nurse and auxiliary nurse). Stratified random sampling was used to ensure that there was a representation of all the nurses working in the different modules at Tygerberg Hospital. Therefore three wards were randomly selected from each module and all the nurses on duty working in the three selected wards were given a questionnaire by the Assistant Director of the specific module. After the data was collected it was analysed through the statistical package for social sciences. The findings of the study showed that nurses have inadequate knowledge regarding standard precautions and the mean score of the nurses overall self reported compliance of standard precautions was 87.5%. The results also showed that when patients are HIV positive nurses intend to over comply the use of personal protective equipment. No association was found between the nurses knowledge and compliance regarding standard precautions. It is therefore important that every nurse should be educated about the basic principles of standard precautions and also the policies and protocols of infection control in order to prevent each nurse from getting infected. Training needs to be implemented starting in the wards through the unit manager to improve all the nurses knowledge and practice. / South Africa

O estudo trata de acidentes com material biológico que ocorreram com os profissionais de saúde, no Hospital de Clínicas de Porto Alegre (HCPA), no período de janeiro de 2006 a dezembro de 2011. Um estudo observacional retrospectivo que objetivou caracterizar a frequência de ocorrência de acidentes ocupacional determinando a exposição a material biológico entre profissionais de saúde. Foram analisados 1.283 acidentes formalmente registrados pelo Serviço de Medicina Ocupacional do HCPA entre janeiro de 2006 a dezembro de 2011. Foi possível constatar a predominância de acidentes com materiais perfurocortantes (80%) dentre todos os acidentes com material biológico registrados no estudo ao longo de 6 anos. Verificou-se que os técnicos de enfermagem e os médicos residentes foram os profissionais que mais se acidentaram. Com relação ao comportamento dos acidentes ao logo destes 6 anos, a análise da série temporal evidenciou que houve uma tendência de aumento dos acidentes com material biológico entre os médicos residentes. Já com os demais profissionais de saúde, a série temporal apresentou-se estacionária. / The study comes to accidents with biological material that occurred with health professionals, Hospital de Clinicas de Porto Alegre (HCPA), from January 2006 to December 2011. A retrospective observational study aimed to characterize the frequency of accidents determining occupational exposure to biological material among health professionals. The study analysed 1,283 formally registered by the Occupational Medicine Department of the institution between January 2006 to December 2011. It was possible to observe the prevalence of accidents with sharps (80%) of all accidents with biological material recorded in the study just 6 years. It was found that the nursing staff and the residents were professionals who were hurt more. With respect to the behavior of these accidents the logo six years, the analysis of time series showed that there was an increasing trend of accidents with biological material among medical residents. Already with other health professionals, the series presented stationary.

Humans are exposed to metals and metal-containing materials daily, either conscious, e.g. using metal tools or objects, or unconscious, e.g. during exposure to airborne metal-, and metal-containing particles. The diffuse dispersion of metals from different sources in the society, and the concern related to its potential risk for adverse effects on humans have gained an increased public and governmental attention both on a national and international level. In this context, the knowledge on metal release from metallic objects or metal-containing particles is essential for health risk assessment. This thesis focuses on the study of metal release from powder particles of stainless steel and Cu-based materials exposed to synthetic body fluids mainly for simulating lung-like environments. The study comprises: i) development of a suitable experimental method for metal release studies of micron sized particles, ii) metal release data of individual alloy constituents from stainless steel powder particles of different particle sizes, and iii) Cu release from different Cu-based powder particles. In addition, the influence of chemical and physical properties of metallic particles and the test media are investigated. Selected results from Ni powder particles exposed to artificial sweat are presented for comparison. The outcome of this research is summarized through ten questions that are formulated to improve the general understanding of corrosion-induced metal release from metallic particles from a health risk perspective. A robust, reproducible, fairly simple, and straightforward experimental procedure was elaborated for metal release studies on particles of micron or submicron size. Results in terms of metal release rates show, for stainless steel powder particles, generally very low metal release rates due to a protective surface oxide film, and Fe preferentially released compared to Cr and Ni. Metal release rates are time-dependent for both stainless steel powder particles and the different Cu-containing powders investigated. The release of Cu from the Cu-containing particles depends on the chemical and compositional properties of the Cu-based material, being either corrosion-induced or chemically dissolved. Moreover, the test medium also influences the metal release process. The metal release rate increases generally with decreasing pH of the test media. However, even at a comparable pH, the release rate may be different due to differences in the interaction between the particle surface and specific media. The nature of particles is essentially different compared to massive sheet in terms of physical shape, surface composition and morphology. The surface area, and even the surface composition of metallic particles, depend on the particle size. The specific surface area of particles, area per mass, is intimately related to the particle size and has a large effect on the metal release process. Release rates increase with decreasing particle size due to a larger active surface area that takes part in the corrosion/dissolution process. The surface area that actually is active in the corrosion and metal release process (the effective area) governs the metal release process for both particles and massive sheet of metals or alloys. For particles, the effective surface area depends also on agglomeration conditions of particles during exposure. / QC 20101119

Biohybrid micromotors propelled by motile cells are fascinating entities for autonomous biomedical operations on the microscale. Their operation under physiological conditions, including highly viscous environments, is an essential prerequisite to be translated to in vivo settings. In this work, a sperm-driven microswimmer, referred to as a spermbot, is demonstrated to operate in oviduct fluid in vitro. The viscoelastic properties of bovine oviduct fluid (BOF), one of the fluids that sperm cells encounter on their way to the oocyte, are first characterized using passive microrheology. This allows to design an artificial oviduct fluid to match the rheological properties of oviduct fluid for further experiments. Sperm motion is analyzed and it is confirmed that kinetic parameters match in real and artificial oviduct fluids, respectively. It is demonstrated that sperm cells can efficiently couple to magnetic microtubes and propel them forward in media of different viscosities and in BOF. The flagellar beat pattern of coupled as well as of free sperm cells is investigated, revealing an alteration on the regular flagellar beat, presenting an on–off behavior caused by the additional load of the microtube. Finally, a new microcap design is proposed to improve the overall performance of the spermbot in complex biofluids.

Ajonuma Louis Chukwuemeka. / "March 2004." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (p. 215-238). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.

In forensic sciences, the serological methods used to determine which body fluid was collected from the crime scene are merely presumptive or labor intensive since they rely on protein detection or on microscopic identification of cells. Given that certain forensic cases may need the precise identification of a body fluid to determine criminal contact, such is the example of a suspected sexual assault of a minor; certainty in the body fluid of origin may depict a precise picture of the events. The identification of loci that show differences in methylation according to the tissue of origin can aid forensic analysts in determining the origin of a DNA sample. The process of DNA methylation occurs naturally in the genome of living organisms and consists in the presence of a methyl group on the carbon 5 of a cytosine, which is typically followed by a guanine (CpG). Analyzing patterns of DNA methylation in body fluids collected from a crime scene is preferential to the analysis of proteins or mRNA since the same extracted DNA used for STR typing can be used for DNA methylation analysis. We have validated and identified loci able to discriminate blood, saliva, semen and vaginal epithelia. In the current study, we have also established the minimum amount of DNA able to provide reliable results using methodologies such as pyrosequencing and high-resolution melt (HRM) analysis for the different markers identified. Lastly, we performed an alternative bioinformatic analysis of data collected using an array that studied methylation in over 450,000 individual cytosines on the human genome. We were able to sort the locations that showed potentially higher methylation differences between body fluids and investigated over 100 of them using HRM analysis. The results of that study, allowed the identification of three new loci able to distinguish blood and two new loci able to distinguish saliva and vaginal epithelia, respectively. The use of DNA methylation patterns to aid forensic investigations started with a publication in 2010, therefore each small contribution such as this work may, similarly to what occured in the biochemistry field, result in the discovery of a method able to put the technology in the hands of forensic analysts.

With increasing environmental awareness, the desire to protect human beings and the environment from adverse effects induced by dispersed metals has become an issue of great concern and interest. New policies, such as REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals) within the European Community, have been implemented to reduce hazards posed by the use of chemicals on producers and downstream users. The generation of exposure assessment data and relevant test procedures able to simulate realistic scenarios are essential in such legislative actions. This doctoral study was initiated to fill knowledge gaps related to the metal release process of stainless steels. A wide range of stainless steel grades, fourteen in total, were investigated. They cover a very broad range of applications, and the focus in the thesis was to simulate a few selected exposure scenarios: precipitation, the human body and food intake. Comparisons were made between metal release from stainless steel alloys and the pure metals that constitute each stainless steel in order to explore the differences between alloys and pure metals, and to provide quantitative data on metal release rates of different alloy constituents. Because of similar surface properties between stainless steel and pure chromium, this metal exhibits similar release rates, whereas iron and nickel exhibit significantly lower release rates as alloy components than as pure metals. Detailed studies were also performed to elucidate possible relations between metal release and steel surface properties. Key parameters turned out to be chromium enrichment of the self-passivating surface film, surface roughness, the electrochemically active surface area and the microstructure of the steel substrate. The degree of metal release increased with decreasing chromium content in the surface oxide, increasing surface roughness, and increasing presence of inhomogeneities in the bulk matrix. More detailed studies were initiated to possibly correlate the nucleation of metastable pits and the extent of metal release. Evidence was given that metastable pits exist even when the stainless steel is passive, and may cause extremely short-lived bursts of released metal before the surface film repassivates again. / QC 20100810

The inherited form of primary open angle glaucoma, a disorder characterized by increased intraocular pressure and retina degeneration, is linked to mutations in the olfactomedin (OLF) domain of the myocilin gene. Disease-causing myocilin variants accumulate within trabecular meshwork cells instead of being secreted to the trabecular extracellular matrix thought to regulate aqueous humor flow and control intraocular pressure. Like other diseases of protein misfolding, we hypothesize myocilin toxicity originates from defects in protein biophysical properties. In this thesis, the first preparative recombinant high-yield expression and purification system for the C-terminal OLF domain of myocilin (myoc-OLF) is described. To determine the relative stability of wild-type (WT) and mutant OLF domains, a fluorescence thermal stability assay was adapted to provide the first direct evidence that mutated OLF is folded but less thermally stable than WT. In addition, mutant myocilin can be stabilized by chemical chaperones. Together, this work provides the first quantitative demonstration of compromised stability among identified OLF variants and placing myocilin glaucoma in the context of other complex diseases of protein misfolding. Subsequent investigations into the biophysical properties of WT myoc-OLF provide insight into its structure and function. In particular, myoc-OLF is stable in the presence of glycosaminoglycans (GAGs), as well as over a wide pH range in buffers with functional groups reminiscent of such GAGs. Myoc-OLF contains significant â-sheet and â-turn secondary structure as revealed by circular dichroism analysis. At neutral pH, thermal melts indicate a highly cooperative transition with a melting temperature of ~55°C. A compact core structural domain of OLF was identified by limited proteolysis and consists of approximately residues 238-461, which retains the single disulfide bond and is as stable as the full myoc-OLF construct. This construct also is capable of generating 3D crystals for structure determination. This data, presented in Chapter 3, inform new testable hypotheses for interactions with specific trabecular extracellular matrix components. To gain further insight into the biological function of myoc-OLF, a facile fluorescence chemical stability assay was designed to identify possible ligands and drug candidates. In the assay described in Chapter 4, the target protein is initially destabilized with a chemical denaturant and is tested for re-stabilization upon the addition of small molecules. The assay requires no prior knowledge of the structure and/or function of the target protein, and it is amendable to high-throughput screening. Application of the assay using a library of 1,280 compounds revealed 14 possible ligands and drug candidates for myoc-OLF that may also generate insights into myoc-OLF function. Due to the high â-sheet content of monomeric myoc-OLF and presence of an aggregated species upon myoc-OLF purification, the ability of myoc-OLF to form amyloid fibrils was suspected and verified. The fibril forming region was confirmed to reside in the OLF domain of myocilin. Kinetic analyses of fibril formation reveal a self-propagating process common to amyloid. The presence of an aggregated species was confirmed in cells transfected with WT myocilin, but to a greater extent in cells transfected with P370L mutant myocilin. Both cell lines stained positive for amyloid. Taken together, these results provide further insights into the structure of myocilin and suggest a new hypothesis for glaucoma pathogenesis. Finally, in a related study, small molecule drug candidates were investigated to treat acid â-glucosidase (GCase), the deficient lysosomal enzyme in Gaucher disease, another protein conformational disorder. Three new GCase active-site directed 3,4,5,6-tetrahydroxylazepane inhibitors were synthesized that exhibit half inhibitory concentrations (IC50) in the low millimolar to low micromolar range. Although the compounds thermally stabilize GCase at pH 7.4, only one of the synthesized analogs exhibits chaperoning activity under typical assay conditions. This successful pharmacological chaperone is also one in which GCase is in its proposed active conformation as revealed by X-ray crystallography. Probing the plasticity of the active-site of GCase offers additional insight into possible molecular determinants for an effective small molecule therapy for GD.