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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

The rpsL gene and streptomycin resistance in Streptococcus gordonii and Streptococcus pyogenes

Vidyasanker, Radhika 13 December 1999 (has links)
Streptomycin resistance in both gram-positive and gram-negative bacteria is usually caused by a single mutation in the rpsL gene. The rpsL gene encodes the S12 protein of the ribosomal complex. The rpsL genes of various bacteria have consensus regions in their sequences. Primers were designed from these consensus pockets and a fragment of the rpsL gene was sequenced from S. gordonii using PCR based methodologies. Using the Multiplex Restriction Sequence PCR(mRS PCR), which used the known primer at one end and a restriction site primer on the other, a gene walk was conducted. In streptomycin resistant strains of S. gordonii, namely GP204, SP204 and SP635, the AAA coding for Lys56 was mutated to ACA, coding for Thr56. The lysine to threonine transition, causing resistance to streptomycin was identical to that expected from the literature. The streptomycin resistance gene of S. pyogenes was mapped using similar techniques. Streptomycin resistant strains S43 ATCC, 543/192/4 and S43/192/30R were studied. In streptomycin resistant S43 ATCC and S43/192/30R strains, the lysine 56 changed to isoleucine and threonine respectively. Surprisingly, the 192/4 had two mutations, in each of the two hotspots in the rpsL gene where mutations due to streptomycin resistance occur. It had the amino acid 56, lysine, mutated to arginine and lysine 101 changed to asparagine. To check if this mutation was stable in the host animal, S43/192/4 P8 (S43/192/4 passaged eight times in mice) was sequenced and the sequence was identical to the streptomycin resistant 192/4. Hence, the lys101 mutation was stable and unlike the ancillary mutations in E.coli and S. typhimurium, which are compensated by new mutations. The pathogenesis of S. pyogenes depends in part on the ability of the pathogen to adhere to the epithelial cells of the throat and the quantity of M protein. Pathogenesis studies done on mice revealed the avirulence of S43/192/4smR strain. To elucidate the reason for this avirulence, the adherence properties and the production of M protein of the two strains S43/192/4smR and S43/192/30R were tested. Qualitative immunoblot analysis of the M protein of 192/4 and 30R revealed no significant difference. Competition ELISA was conducted to quantitate the M protein, and this also did not show any significant difference in the M protein levels. The adherence of 30R and 192/4 was measured on human pharyngeal epithelial cell line. The adherence properties of S43/192/4 SmR, was no different from other strains in this experiment. Electron microscopy, using immunogold to highlight the M protein on the cell surface showed no differences. / Graduation date: 2000
102

Application of vaccination protocols to manage beef cattle productivity and mitigate production risk

Horne, Willy J. 16 January 2010 (has links)
The U.S. beef industry is very large with many inter-connected facets. Nutrition and health are key components of a system striving to compete economically while striving to produce a high quality product. The decisions made in one part of the system may often determine outcomes in the other parts of the system. Therefore, it is necessary to look at the beef industry in a systems type of framework. Each management decision is likely tied to a result that may alter several other management questions. At the cow/calf level, producers must decide whether or not to vaccinate their calves. Vaccination leads to reduced disease incidence and severity in the feedyard, thus being beneficial to the feeder. However, if the feedlot does not respond economically in any way, producers may feel that it is not warranted to vaccinated calves. Pre-conditioning programs work in the same manner as they may have beneficial effects for the feeder but not for the harvester. Therefore, pre-conditioning may not be a program that is valued back to the farm level. Answers to these kinds of questions are hard to ascertain. Each segment has its own demands and drivers, which determine how much it can reward to other segments for their efforts. Because the market is continuously changing, the target rewards are changing as well. Therefore targets cannot be theorized, rather exact relationships should be shown. In this dissertation, it is intended to characterize the relationships vaccination protocols and other management strategies can have on various aspects of cattle performance in various industry segments.
103

Influence of Diet on Performance Parameters, Intestinal Lesion Development, and Oocyst Cycling in Live Oocyst Vaccinated Replacement Broiler Breeders

Oden, Leslee Ann 2009 August 1900 (has links)
Two consecutive experiments were conducted to evaluate the influence of dietary composition, specifically protein and amino acid profile, on performance parameters, oocyst output, and lesion development in male and female replacement broiler breeders of two different genetic lines vaccinated with a live coccidiosis vaccine. Dietary formulations were based on either breeder specific recommendations or formulations of a broiler integrator. On day 28, males of each genetic line were added to female pens to evaluate the effect of co-mingling on male performance. Lesion assessment was performed on three separate occasions per each experiment. Fecal material was collected to determine oocyst cycling patterns. During experiment 1, flock uniformity was improved (P less than/equal to 0.05) in Line A males fed the integrator diet. Increased body weight and improved uniformity of Line B females was observed with the breeder recommended diet. Co-mingling negatively impacted (P less than/equal to 0.05) male body weight. Multiple oocyst peaks were observed in both genetic lines, with the first peak occurring at approximately 16 to 18 days post placement. This first peak tended to have the highest observed magnitude and corresponded with the highest level of intestinal lesions observed during the experiment. In experiment 2, diet impacted (P less than/equal to 0.05) average body weight in Line A males, Line B males, and Line B females. Line A males fed the breeder recommended diet had increased (P less than/equal to 0.05) body weight at the termination of the experiment. Line B males and females fed the breeder recommended diet had increased (P less than/equal to 0.05) body weights throughout the experiment beginning on day 7. Negative effects (P less than/equal to 0.05) on male body weight resulting from co-mingling were observed. Oocyst peaks were delayed and at a lower magnitude in both genetic lines compared to peaks observed in experiment 1. Dietary interactions were observed in both experiments where magnitude of peak, duration of oocyst output, and severity of lesion development was influenced by diet in both male and female genetic lines. These data indicate that co-mingling negatively impacts male performance and dietary composition can impact male and female performance, oocyst cycling, and lesion development during coccidiosis vaccination in replacement broiler breeders and should be taken into consideration when rearing replacement broiler breeders.
104

Gesundheitsvorsorge bei Kindern : eine empirische Untersuchung des Impfverhaltens bei Masern, Mumps und Röteln /

Kriwy, Peter. January 2007 (has links)
Dissertation--Kiel--Philosophische Fakultät, Christian-Albrechts-Universität, 2006. / Bibliogr. p. 175-182.
105

Simulating The Impacts Of Mass Vaccination With Live Attenuated Human Rotavirus Vaccine In A Developing Country

Rose, Johnie, II January 2010 (has links)
Thesis(Ph.D.)--Case Western Reserve University, 2010 / Title from PDF (viewed on 2010-01-28) Department of Epidemiology and Biostatistics Includes abstract Includes bibliographical references and appendices Available online via the OhioLINK ETD Center
106

Essays in health economics

Mulligan, Karen Michelle 06 July 2012 (has links)
This dissertation consists of three chapters on health economics, two of which focus on contraception and the third on vaccination. Chapter one examines the impact of state-level contraception insurance coverage mandates on women's fertility outcomes. It utilizes variation in mandated insurance coverage for contraception across states and over time to determine the causal impact of insurance coverage of contraception on fertility outcomes, specifically abortion rates and birth rates. State-level results indicate that a mandate decreases abortion rates by 6% in the year of introduction and decreases birth rates by 3% two years following introduction, with the magnitude of both effects remaining steady over the long run. Chapter two utilizes longitudinal data on varicella (chicken pox) immunizations in order to estimate the causal effects of state-level school-entry and daycare-entry immunization mandates within the United States. We find significant causal effects of mandates upon vaccination rates among preschool children aged 19-35 months; these effects appear in the year of mandate adoption, peak two years after adoption, and show a minimal difference from the aggregate trend about six years after adoption. For a mandate enacted in 2000, the model and estimates imply that roughly 20% of the short-run increase in state-level immunization rates was caused by the mandate introduction. We find no evidence of differential effects for different socioeconomic groups. Combined with the previous cost-benefit analyses of the varicella vaccine, the estimates suggest that state-level mandates have been effective from an economic standpoint. Chapter three utilizes variations in access to emergency contraception (EC) across states to determine the impact of over the counter access on abortion rates, birth rates, and risky sexual behavior. Using state-level data, a flexible time specification finds that giving individuals over the counter access to EC reduces births and increases risky behavior, which is captured by STD rates. These effects are larger for adults compared with teenagers, however, there are not significant differential effects by race. Finally, the effects are increasing over time following the legislation. / text
107

Prevalence and predictors of maternal seasonal influenza vaccination in Hong Kong

Yuen, Yuet-sheung, Carol, 袁月嫦 January 2013 (has links)
Pregnant women infected with influenza virus are more likely to experience severe complications compared with their non-pregnant peers. Yet influenza vaccine uptake is low among pregnant women. The purpose of this study was to assess the prevalence and predictors of seasonal influenza vaccine uptake among pregnant women in Hong Kong. Using a multi-centre cross-sectional design, we recruited 2,822 new mothers during their immediate postpartum stay at all eight public obstetric hospitals over a three-month period from April through June 2011. We assessed their antenatal maternal influenza vaccination status as well as health beliefs and perceptions toward influenza and influenza vaccination. Bivariable and multivariable logistic regression was used to identify the predictors of vaccination uptake. Only 49 (1.7%; 95% CI 1.3% to 2.3%) participants were vaccinated during pregnancy. Fears that the vaccine would harm their foetuses or themselves were the most common reasons for not being vaccinated. Being aware of vaccination recommendations (OR=2.69; 95% CI 1.06, 6.82), being advised by a health care provider (HCP) to be vaccinated (OR=6.30; 95% CI 3.19, 12.46), a history of influenza vaccination (OR=2.47; 95% CI 1.25, 4.91), perceived susceptibility to influenza infection (OR=3.67; 95% CI 1.64, 8.22), and perceived benefits of influenza vaccination (OR=9.98; 95% CI 3.79, 26.24) were all independently associated with vaccination. Perceived barriers to vaccination (OR=0.17; 95% CI 0.07, 0.40) were strongly associated with failure to vaccinate. A qualitative descriptive design was also used to explore a broad spectrum of health knowledge and beliefs of participants regarding influenza infection and influenza vaccination during pregnancy. An interview guide was developed based on the Health Belief Model. A sub-sample of participants who completed the quantitative study were invited to take part in the qualitative interviews. A total of 32 postpartum women were interviewed and only two had been vaccinated during pregnancy. Following thematic analysis, three themes emerged that further highlighted the pregnant women’s perceptions toward influenza vaccine and their decision-making process, perceived risk of influenza infection, perceived risk of an influenza vaccine, and decision-making cues. Overall, participants held negative impressions about influenza vaccination during pregnancy. This could be because of misconceptions and underestimation of the threats of influenza infection to themselves and their foetuses. They were also confused about the safety and efficacy of the influenza vaccine. Participants were confused about the differences between preventive strategies and treatment for influenza and HCPs did not offer or recommend vaccination. Because of negative media reports about the pros and cons of vaccination, participants were hesitant to receive the vaccine. Nevertheless, findings suggested that motivating forces for vaccine acceptance were a high prevalence of circulating influenza infection during their pregnancy and HCP recommendations and reassurances that the vaccination was safe, effective, and beneficial for the foetus. Vaccination promotion strategies need to focus on encouraging HCPs to discuss vaccination with their pregnant clients and provide accurate and unbiased information about the risks of influenza infection and the benefits of vaccination. / published_or_final_version / Nursing Studies / Doctoral / Doctor of Nursing
108

An Analysis of Household-reported Health Status and Socio-demographic Characteristics Associated with Adolescent Influenza Vaccination Rates in the United States: 2008 National Immunization Survey-Teen

Liu, Lindy 11 November 2010 (has links)
Background: Influenza is a highly contagious but preventable acute respiratory illness associated with high morbidity. Seasonal influenza affects approximately 20% to 40% of children and adolescents. Annual influenza vaccination is an effective approach to prevent illness but recent studies suggests that adolescents are underutilizing important preventive health services and that influenza vaccination coverage in high risk adolescents is also suboptimal. The purpose of this study was to examine the association between household reported health status and socio-demographic characteristics of U.S. adolescents who reported receiving an influenza vaccination. Methods: Data from the 2008 National Immunization Survey were assessed examining various demographic and socioeconomic characteristics, as well as reported health status of non-institutionalized adolescents in the U.S. The sample was limited adolescents aged 13-17. Odds ratios were calculated and multivariate logistic regression was conducted. P-values of < 0.05 and 95% confidence intervals were used to determine statistical significance. Results: There were 29063 total observations with 18.9% reporting receiving the influenza vaccine. The results of this study indicate that sex, race and ethnicity, poverty status, health insurance status, asthma status, having an underlying health condition, missed school days due to illness or injury, and maternal age are associated with getting immunized against influenza. As one might expect those who reported having health insurance, having asthma, and having an underlying health condition had higher likelihood of vaccine. Interestingly, non-Hispanic other race and multi-race teens in the study were the most likely to receive the influenza vaccine compared with non-Hispanic white teens. Conclusions: This study further examines the impact of socio-demographic disparities and health status on influenza vaccination coverage. Although the current influenza vaccine recommendations now include all individuals ages 6 months and older, it should still be important to recognize disparities and inequalities which contribute to non-vaccination or under-vaccination. Improved understanding of demographic and socioeconomic characteristics, as well as existing underlying health conditions, will facilitate the path to improving interventions, vaccination rates, and subsequent reduction in the burden of this preventable disease.
109

Lietuvos sveikatos priežiūros įstaigų darbuotojų požiūris į vakcinaciją / Attitudes to vaccination of lithuanian health care workers

Beliauskienė, Rita 09 July 2011 (has links)
Darbo tikslas. Įvertinti Lietuvos sveikatos priežiūros įstaigų darbuotojų požiūrį į vakcinaciją. Metodika. Kad įvertinti Lietuvos sveikatos priežiūros įstaigų darbuotojų požiūrį į vakcinaciją, buvo atliktas paplitimo tyrimas. Buvo apklausta 1693 respondentai, dirbantys asmens sveikatos priežiūros įstaigose. Duomenys apdoroti SPSS (13) kompiuterine programa. Analizei taikytas Pearson‘o &#967;2 testas ir statistiniam išvadų tikrinimui pasirinktas reikšmingumo lygmuo 0,05. Rezultatai. Anketinė apklausa parodė, kad Lietuvos sveikatos priežiūros įstaigų darbuotojai teigiamai žiūri į vakcinaciją. Nors skiepijasi 54,8% bendrosios praktikos gydytojų, 55,9% terapeutų ir kitų specialistų bei 51,6% slaugytojų, visgi jie nurodė, kad vakcina žymiai efektyvesnė ir mažiau kainuoja nei kitos medicininės paslaugos – 67,0% bendrosios praktikos gydytojų, 69,1% terapeutų ir kitų specialistų bei 60,3% slaugytojų ir kad skiepai duoda žymiai daugiau naudos nei žalos (84,9% bendrosios praktikos gydytojų, 87,5% terapeutų ir kitų specialistų bei 71,7% slaugytojų). Iš dažniausiai nurodytų nesiskiepijimo priežasčių, dauguma respondentų nurodė, kad nesiskiepija nuo gripo dėl to, kad saugosi nuo gripo stiprindami sveikatą (19,3% bendrosios praktikos gydytojų, 18,9% terapeutų ir kitų specialistų bei 15,8% slaugytojų), niekada gripu neserga (20,0% bendrosios praktikos gydytojų, 17,0% terapeutų ir kitų specialistų bei 15,2% slaugytojų), įgyjamas natūralus imunitetas (22,2% bendrosios praktikos gydytojų, 8,0%... [toliau žr. visą tekstą] / Objective: To determine the Lithuanian health care institutions workers opinion about vaccination. Methods: In order to determine the Lithuanian health care institutions workers opinion about vaccination spread research was performed. Were polled 1693 respondents working in health care institutions. The data was analysed using SPSS computer program. There was used Pearson Chi-Square test and to check statistical reliability was choose the difference statistically insignificant 0,05. Results: Questionnaire date shows positive Lithuanian health care institutions workers opinion about vaccination. Even though only 54,8% of common practice physicians, 55,9% therapeutists and other specialists and 51,6% nurses were vaccinated themselves but they indicated that vaccination is more effective and less expensive than other medical service – 67,0% of common practice physicians, 69,1% therapeutists and other specialists and 60,3% nurses and that vaccination is more useful than harmful (84,9% of common practice physicians, 87,5% therapeutists and other specialists and 71,7% nurses). The major reason why the respondents are against vaccination, especially against influenza virus, is that they strengthen their health to protect themselves against virus (19,3% of common practice physicians, 18,9% therapeutists and other specialists and 15,8% nurses), never have flu (20,0% of common practice physicians, 17,0% therapeutists and other specialists and 15,2% nurses), and acquire natural immunity... [to full text]
110

Influenza Vaccination in Solid Organ Tranplant Recipients

Baluch, Aliyah Unknown Date
No description available.

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