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Sensitivity of HIV-1 subtype C viruses to Griffithsin, cyanovirin-N and scytovirin: potential HIV-1 microbicidesAlexandre, Kabamba Bankoledi 07 May 2013 (has links)
Thesis (Ph.D. (Virology))--University of the Witwatersrand, Faculty of Health Sciences, 2012 / The majority of HIV-1 infections around the world occur via sexual intercourse and
women, especially in developing countries, are disproportionately affected. Recently a
number of strategies have been proposed to control the spread of HIV, among these the
use of microbicides to prevent the sexual transmission of the virus. A clinical trial of 1%
tenofovir gel that conferred up to 39% protection provided a proof-of-concept that an
anti-HIV microbicide is feasible. Various other compounds, acting at different stages of
HIV-1 life cycle, are also being investigated as potential microbicides. These include the
lectins Griffithsin (GRFT), cyanovirin-N (CV-N) and scytovirin (SVN). GRFT was
isolated from the red algae griffithsia sp. while CV-N and SVN were isolated from the
blue green alga Nostoc ellipsosporum and the cyanobacterium Scytonema varium,
respectively. These lectins bind mannose-rich glycans found on the surface of HIV-1
envelope and act as entry inhibitors. Although HIV-1 subtype C is the main cause of
infections around the world, almost all studies conducted with GRFT, CV-N and SVN
are based on subtype B viruses. The Chapter Two sought to establish the neutralization
sensitivity of HIV-1 subtype C viruses to the three lectins, using both a cell line and
primary cells, and compared this sensitivity to subtype B. This Chapter also examined
mannose-rich glycans on HIV-1 that are involved in GRFT, CV-N and SVN binding. The
conclusion from this study was that the neutralization of subtype C viruses by these
lectins is similar to subtype B and that the 234 and 295 mannose-rich glycans were
involved in their interaction with the virus. In general these data supported further studies
on the use of GRFT, CV-N and SVN for prevention of HIV-1 subtype C sexual
transmission. In Chapter Three, the ability of GRFT to expose the CD4 binding site
(CD4bs) on HIV-1 gp120 is explored. I found that this exposure resulted in the
enhancement of HIV-1 binding to plates coated with anti-CD4bs antibodies b12 and b6
or the CD4 receptor mimetic CD4-IgG2. This lectin also synergized with b12 and HIVpositive
plasma containing antibodies to the CD4bs to neutralize the virus. Furthermore,
the glycan at position 386, which shields the CD4bs, was shown to be involved in both
GRFT enhancement of HIV-1 binding to b12 and b6 and in the synergistic interaction
between the lectin and these antibodies. The importance of this study is that it
investigated in details the effect of GRFT binding on HIV-1 envelope and also suggests
this lectin can be used in combination with anti-HIV-1 antibodies to synergistically
enhance the anti-viral activity. In Chapter Four I investigated GRFT, CV-N and SVN
inhibition of the virus binding to the DC-SIGN receptor and their inhibition of the DCSIGN
transfer of HIV-1 to target cells. These lectins only moderately inhibited the virus
binding to the receptor while they potently inhibited its transfer to target cells. However,
the inhibition of transfer was stronger when the virus bound the lectins after binding the
DC-SIGN receptor compared to when it bound the lectins prior to binding the receptor.
These three lectins can, therefore, inhibit the sexual transmission of HIV-1 since the DCSIGN-
mediated transfer of the virus to susceptible cells is pivotal to this mode of
transmission. Chapter Five is an investigation of the ability of HIV-1 subtype C to escape
GRFT, CV-N and SVN, which involved growing the virus under escalating
concentrations of these compounds. This was to know how this virus behaves under
conditions of continuous exposure to the lectins. I found that HIV-1 subtype C became
increasingly resistant to the lectins and viral envelope sequence analysis showed that this
was associated with the deletion of mannose-rich glycans on gp120. Furthermore, of the
11 potential mannose-rich glycosylation sites on gp120 seven (230, 234, 241, 289, 339,
392 and 448) were involved in GRFT, CV-N and SVN resistance. Thus, the conclusion
was that although these three lectins are potent inhibitors of HIV-1 infection, the virus is
also able to escape their neutralization by deleting mannose-rich glycans on its envelope.
However, the fact that escape to these lectins involved multiple deglycosylation and was
only partial suggests that HIV-1 subtype C escape from GRFT, CV-N and SVN in a
microbicide formulation may not be an easy process. We discuss the implications of these
findings in Chapter Six and suggest future studies that could complement data presented
in this thesis. Overall our data show that GRFT, CV-N and SVN can prevent the sexual
transmission of both free and DC-SIGN associated HIV-1 particles and supports further
development of these lectins as microbicides against HIV-1.
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The association between knowledge, perceptions, medication adherence and blood pressure control among Chinese hypertensive patients. / 中國高血壓患者的知識, 感知, 藥物依從性和血壓控制之間的相互關係 / CUHK electronic theses & dissertations collection / Zhongguo gao xue ya huan zhe de zhi shi, gan zhi, yao wu yi cong xing he xue ya kong zhi zhi jian de xiang hu guan xiJanuary 2013 (has links)
Liu, Qilin. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 97-110). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts also in Chinese; appendixes includes Chinese.
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Stroke Prevention in a Neighborhood with a High Incidence of Stroke: Exploring a Community’s UnderstandingUnknown Date (has links)
Stroke continues to plague the United States, affecting 795,000 people annually. Although stroke mortality has decreased, the overall incidence of stroke appears essentially unchanged. With a population that is projected to increase in age and stroke risk over the next 10-15 years, this is concerning. Current stroke prevention education may not be adequately tailored to community learning needs. Analyzing existing demographic data within electronic medical records may allow healthcare systems to identify high-risk neighborhoods by geocoding stroke diagnoses and then completing a qualitative analysis within the target community of specific stroke knowledge deficits. That information may then inform stroke prevention education for that neighborhood. A descriptive, exploratory approach was used to identify a community with a high incidence of stroke using geocoded demographic data from patients coding out with a stroke diagnosis. Qualitative interviews conducted within the community yielded the following themes: fragmented knowledge of stroke causes and risk factors, unawareness of hypertension and diabetes as significant risk factors for stroke, knowing but experiencing challenges to engaging in healthy practices—specifically, diet and exercise, and financial barriers to healthcare resources. While most of the participants had adequate healthcare coverage and reported regular interactions with a primary healthcare provider, this community continued to experience a higher incidence of stroke than surrounding neighborhoods. The findings of this study highlighted specific challenges to stroke prevention that may inform future stroke prevention initiatives. Future research in other communities using this approach may provide additional insights into the specific knowledge deficits unique to communities, as well as revealing patterns and trends in stroke prevention knowledge. Approaching stroke prevention education using only data obtained from large registries may provide a broad overview of knowledge deficits, but lack the specificity necessary to effectively address stroke knowledge needs at the community level. Recognizing the challenges inherent with behavior modification for implementing lifestyle changes should also be considered when designing future stroke education. Harnessing technology in the form of web applications, text messaging, and email for maintaining communication with patients may improve effectiveness of stroke prevention interventions. Implementing a comprehensive health promotion program that addresses specific community needs with tailored health education and behavioral support may lead to decreased incidence of cerebrovascular disease in this community and provide a model for managing other preventable diseases. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2019. / FAU Electronic Theses and Dissertations Collection
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Nurses’ counseling to mothers to prevent mother to child transmission of HIV through breastfeeding : A qualitative studyStaflin, Emma, Lundkvist, Jennie January 2011 (has links)
Introduction: HIV is a serious problem in Namibia, 13.1% of the adult population is HIV-positive or is a carrier of AIDS. This is one of the highest numbers in the world. HIV is passed from mother to child during pregnancy, during labour or through breast milk. 18.8 % of the pregnant mothers in Namibia who is in contact with the maternity welfare have HIV. Aim: The aim of the study was to describe nurses’ counseling to mothers to prevent mother to child transmission of HIV through breastfeeding. Method: Eight nurses working with PMTCT of HIV were interviewed in Namibia. The interviews were transcribed and a content analysis was made. 18 sub-categories and seven categories were found. Findings: It is important that nurses provide individual counseling, are supportive and motivate the mothers. Poverty is an obstacle for the mothers, stigmatization occurs and cultural differences can have influence on the mothers. It is also important that nurses are updated in counseling and PMTCT. Conclusion: Nurses should provide mothers with the correct information in a pedagogical way. Nurses need to be aware of obstacles for the mothers and their families to be able to meet their different demands. Men are not involved in PMTCT-counseling and nurses think that partner involvement would benefit PMTCT of HIV.
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Effect of a sensory minimization intervention on the physiological stability and pain response of preterm infantsAita, Marilyn January 2008 (has links)
Light and noise in the neonatal intensive care unit (NICU) may be stressful to infants who are born preterm. The goals of this research were twofold: a) to evaluate the physiological stability (heart rate, heart rate variability, and oxygen saturation) of 28 to 32 gestational age preterm infants while wearing eye goggles and earmuffs for a 4-hour period, and b) to evaluate their pain response (heart rate and heart rate variability) during a painful procedure (heel lance) following the 4-hour period that they had worn the eye goggles and earmuffs. Preterm infants were recruited from four university-affiliated teaching hospitals in the Montreal region that have a level III NICU. A cross-over trial allowed the evaluation of physiological stability in a sample of 54 infants, and a randomized controlled trial with 44 infants was used to evaluate pain response. For the crossover trial, preterm infants were randomized in one of the following sequences: intervention - control or control - intervention. In the RCT, the first randomized study period (A or 8) of the cross-over trial determined whether preterm infants were or were not wearing eye goggles and earmuffs prior to a heel lance procedure. Data were collected using the Somte™ device allowing the continuous recording of outcome measures and infants were videotaped during the study periods for evaluation of potentially confounding variables. Results of the RM~ ANOVA revealed that infants were more physiologically unstable while wearing the eye goggles and earmuffs. This was shown by signs of stress, such as a significantly higher maximum heart rate and a significantly lower high frequency power (heart rate variability), during the intervention period compared with the control period. [...] / La lumière et le bruit dans l’unité néonatale peuvent être particulièrement stressants pour les prématurés. Les buts de cette étude étaient d’évaluer chez des prématurés de 28 à 32 semaines d’âge gestationnel: a) leur stabilité physiologique (rythme cardiaque, variabilité du rythme cardiaque et saturation d’oxygène) lorsqu’ils portent des lunettes et des couvre-oreilles pendant une période de 4 heures, et b) leur réponse à la douleur lors d’une prise de sang au talon (rythme cardiaque et variabilité du rythme cardiaque) après la période de 4 heures où ils ont porté les lunettes et les couvre-oreilles. Les prématurés ont été recrutés dans quatre centres hospitaliers de la région de Montréal qui possèdent une unité néonatale de soins intensifs. La stabilité physiologique a été évaluée à l’aide d’un plan croisé avec un échantillon de 54 prématurés alors que la réponse à la douleur a été évaluée à l’aide d’un essai clinique randomisé avec un nombre de 44. Pour le plan croisé, les prématurés ont été randomisés dans l’une des séquences suivantes : intervention - contrôle ou contrôle - intervention et pour l’essai clinique randomisé, la première période de la randomisation réalisée pour le plan croisé (A ou B) a déterminé si les prématurés portaient ou non les lunettes et les couvre-oreilles avant la prise de sang au talon. Les données ont été collectées à l’aide d’un appareiilage (Somté™) qui permettait un monitorage continu des variables dépendantes et des enregistrements vidéo des prématurés ont été réalisés pour l’évaluation de variables potentiellement confondantes.
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Epidemiological investigation of highly pathogenic porcine reproductive and respiratory syndrome (HP-PRRS) in small and medium scale swine farms in the Cambodian Meking lowland regionTornimbene, Barbara January 2013 (has links)
No description available.
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Studies on the remineralization of white spot lesions : longitudinal assessment with quantitative light-induced fluorescence /Al-Khateeb, Susan. January 1900 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst. / Härtill 6 uppsatser.
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A comparison of systolic blood pressure in women with and without lymphedema following surgery for breast cancerArvidson-Hawkins, Deborah M. January 2006 (has links)
Thesis (M.A.)--University of South Florida, 2006. / Title from PDF of title page. Document formatted into pages; contains 29 pages. Includes bibliographical references.
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Estimating the preventable portion of lifestyle-related reproductive casualtiesRoss, Susan E. January 1984 (has links)
The purpose of this study was to review the evidence linking maternal and paternal lifestyle habits in the preconception and prenatal period to adverse reproductive outcomes; to determine either the proportion of reproductive casualties which could be attributed to lifestyle risk, thus be amenable to prevention, or the information required to estimate the preventable portion of lifestyle-related reproductive casualties; and to examine a method for surveillance of reproductive health in the community which would provide the basis for a comprehensive information system suited to the needs of the research, planning, preventive medicine and health promotion communities.
As a means of managing the size of the study report, only a representative set of lifestyles (smoking, alcohol consumption and nutrition) and research literature (major cohort and case-control studies in human populations) was reported in detail. A method was developed to review and describe the degree to which the evidence meets established criteria for causal association. The most recently available prevalence data for determining smoking, alcohol and nutritional risk, and incidence data for seven reproductive outcomes (infertility, spontaneous abortion, stillbirth, infant mortality, congenital anomalies, fetal growth and morbidity) in the British Columbia population were used to calculate the preventable portion of reproductive casualties in this community. A review of the variables required, compared with the data available, provided the basis for recommendations regarding a reproductive health information system to support community surveillance, evaluation and research.
The study supports the conclusion that there is evidence of a causal link between exposure to lifestyle risks and the majority of adverse reproductive outcomes selected as indicators of reproductive health. The calculation of the preventable portion (etiologic fraction) of lifestyle-related reproductive casualties in British Columbia suggests the preventable portion associated with single lifestyle risk variables may be in the range of 10-50 percent. A more extensive and up-to-date set of population data for British Columbia is required to determine an accurate estimate. The benefits to be derived from an improved information system were detailed in the study. Reproductive health data collected for British Columbia is primarily outcome oriented with very little input data on which to base rational planning decisions for the improvement of reproductive health outcomes.
The study recommends that a more comprehensive reproductive health information system, with an integrated, linked data base, be considered a high priority by government and all institutions, agencies and individuals working to improve reproductive health outcomes in British Columbia. The potential to improve reproductive health is significant enough to warrant action at the clinical and community level, but additional data are required to plan cost-effective intervention strategies, to monitor improvements in reproductive health, and to support applied research initiatives. / Medicine, Faculty of / Population and Public Health (SPPH), School of / Graduate
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Eye injury prevention in industry. The identification of eye injury problems and the status of preventitive programs: a planning studySchmidt, Brian Thomas January 1978 (has links)
A study was undertaken to examine the major eye injury problems in industry, to determine the hazards that caused them, and to develop methods for improving industrial eye protection programs so as to reduce the incidence of eye injuries. The study was conducted in Alberta through the Occupational Health and Safety Division of Alberta Labour and the Alberta Workers' Compensation Board.
A review of literature was performed to determine the status of eye protection programs, current epidemiological investigations and modes of protection, and to search for historical, legislative and cost benefit information.
The project consisted of seven studies which were designed and carried out independently but, together, would provide a wide perspective concerning eye protection in industry. These studies were:
a) A Review of W.C.B. Statistical Master File Data - which was concerned with a cumulative review of every eye injury claim received by the Workers' Compensation Board over the years 1974, 1975 and 1976. This included a review of Permanent disability claims, claims for lost work time and claims where only medical aid was required.
b) A Review of Selected W.C.B. Personal Medical Files - which was concerned with the detailed review of eye injury claims from fifteen high eye injury risk industry classes. Each medical file was examined individually, paying particular attention to prevention-oriented information.
c) A Survey of Occupational Health and Safety Officers - where thirty-one occupational health and safety officers (inspection personnel) were given an in-depth interview to obtain their perceptions and informed opinions on the nature of eye injury hazards, compliance factors, and the status of eye protection programs in industry.
d) A Survey of Occupational Health and Safety Personnel - where questionnaires were sent to over six hundred persons in Alberta, identified as being involved in the provision of occupational health and safety services in industry. This included physicians, nurses, safety personnel, and persons in government. Questions were similar to those in Section c.
e) A Review of the Minutes of Selected Joint Work Site Committees in Alberta - where the minutes of selected meetings concerning health and safety on the work site between management, the worker, and government, were analyzed to determine the extent of the unsolicited concern for eye injury prevention in companies which were known to have incurred a large number of eye injuries.
f) A Review of Anecdotal Data - where several interviews were
held with union and management representatives to determine the concern and need for eye injury prevention, and the development of eye protection programs at a policy level in industry. The comments and concerns of many other persons were also considered.
g) A Review of Selected Site Visits to Industries in Alberta -where the researcher made six plant visits to better understand the conditions which lead to eye injuries and the problems in implementing preventive programs.
It was found that industries involved in the manufacture or use of metal products, chemicals or construction materials were at high risk. More specifically, however, it was determined that certain occupational groups such as machinists, plumbers and pipefitters, welders, and mechanics were also at high eye injury risk. It was concluded that occupational classification and eye injury hazards should be treated as a basis to eye injury prevention.
Injuries were found generally to occur most frequently among the young and inexperienced workers, while grinding and welding operations were found to be the most prevalent source of injury. Injuries occurred most often at certain times of the day, and there was some question of the effects of boredom and fatigue.
It was found that there is a lack of knowledge and education concerning standards of eye protection and in the proper selection of the protector for the hazard. The physical strength of the protector was minor, however, in comparison to the need for better protector design and fitting of the device to the face of the worker.
It was concluded that companies must be encouraged to develop eye protection policies as a basis to the provision of eye protection programs. A plan was recommended for the improvement of eye protection programs in industry. This included the presentation of a comprehensive eye protection program formulated through a review of literature on the subject, and the elucidation of a system of occupational vision care involving the interaction of all groups concerned with eye injury prevention in industry. / Medicine, Faculty of / Population and Public Health (SPPH), School of / Graduate
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