45 research outputs found
The development of latent fingerprints by zinc oxide and tin oxide nanoparticles prepared by precipitation technique
No full textCalcium affects host-pathogen interactions of Pseudomonas aeruginosa with lung epithelial cells
No full textPseudomonas aeruginosa is one of the key bacterial pathogens that cause acute, chronic, and lethalinfections in the lungs of patients with cystic fibrosis (CF). P. aeruginosa adheres to the mucosal
epithelium of the airways to initiate infections, eventually internalizing and establishing a niche.
Ca²⁺ is a potent cellular signal has been shown to exist in abundance in pulmonary fluids of CF
patients and trigger the expression of virulence factors in P. aeruginosa. However, its role in the
regulation of host-pathogen interactions is not well understood. In this dissertation, we study the
role of Ca²⁺ in adherence, invasion, and intracellular replication of P. aeruginosa in lung epithelial
cells and its role in the regulation of virulence factors (expression of virulence genes, flagella, and
biofilm production) during infection. Two human lung epithelial cell lines, A549 and CuFi-5 (homozygous
for the Δ508 mutation in CF) cells infected with PAO1 and FRD1 strains in low and high
Ca²⁺ conditions were used for this study. We employ the adhesion assay, immunofluorescence,
and scanning electron microscopy (SEM) to study the adhesion of P. aeruginosa to lung epithelial
cells. The data suggests a significant increase in adherence in high Ca²⁺ with both cell lines. A
similar observation was made with the invasion and escape studies. Ca²⁺ binding protein, EfhP,
is reported to regulate invasion, intracellular survival, and escape, whereas it plays an insignificant
role in adherence. Transcriptome sequencing (RNA-seq) and quantitative RT-PCR analysis also
help to understand the importance of Ca²⁺ in the regulation of adhesin transcription (fliC, pilA
and lecA), but this response depends on bacterial strains and the cell line. The Ca²⁺-dependent
upregulation of fliC leads to an increased proportion of flagellated bacteria within a population.
Ca²⁺ also upregulates other virulence factors of P. aeruginosa that could aid biofilm production,
biomineralization, and the production of reactive oxygen species. Here, we provide evidence for
P. aeruginosa host cell escape and Ca²⁺-mediated activation of P13K and Akt that results in P
aeruginosa invasion and intracellular survival within lung epithelial cells. Our study provides insight
into understanding the regulatory potential of Ca²⁺ and Ca²⁺ binding protein, EfhP, in P.
aeruginosa infections during CF
Spectroscopic characterization of iron-oxygen intermediates in human aromatase (CYP19A1)
No full textCYP19A1 or aromatase, is a human steroidogenic P450 important for estrogen biosynthesis in humans. Over activation of aromatase results in malignancies of the breast tissue, especially in post menopausal women. In fact, aromatase inhibitors constitute the front line therapy for estrogen receptor positive (ER+) breast cancer in post-menopausal women which accounts for over 70% of all breast cancer cases in the United States.
Starting with its androgenic substrates, testosterone and androstenedione, CYP19A1 forms estradiol and estrone utilizing one molecule of atmospheric oxygen and two reducing equivalents in the form of NADPH. This is accomplished in a three-step process one of which involves a carbon-carbon bond scission and aromatization. The catalytic mechanism of P450s has been long studied and it is well known that an oxo-ferryl π-cation radical, known as “Compound 1” in P450 chemistry is the reactive intermediate that catalyzes most of the reactions of P450s. The identity of the reaction intermediate that catalyzes the terminal step estrogen biosynthesis by CYP19A1 is still a mystery. There is evidence in the literature suggesting the involvement of Compound 1 via a hydrogen abstraction that initiates deformylation and subsequent aromatization. There is also suggestion of the peroxo-anion or “Compound 0” acting as a nucleophile, attacking the electrophilic carbonyl carbon of 19-oxo-androstenedione forming a peroxide adduct that then fragments to produce acyl-carbon cleavage.
Owing to the interesting chemistry CYP19A1 catalyzes and its role in human health I focused my attention towards elucidating the mechanism of this critical enzyme with the hope that a detailed picture of the workings of CYP19A1 will help guide efforts to make more specific inhibitors and improve breast cancer prognosis.
CYP19A1 is a membrane-bound hemeprotein with a rich spectroscopic landscape thus affording an opportunity to apply a repertoire of biophysical approaches to help piece together a reaction mechanism. I used the Nanodisc technology to stabilize CYP19A1 in its native membrane-like environment to obtain a mono-disperse, stable and homogenous enzyme preparation that is amicable to the optical, resonance Raman (rR) and electron paramagnetic resonance (EPR) spectroscopy and also, cryoradiolysis and cryospectroscopy. The approach I have applied in this project has been that of characterizing the individual fate of reaction intermediates on their way from substrates to products thereby catching them ‘in action’.
My cryospectroscopy, EPR, rR and steady state kinetics efforts outlined in this doctoral thesis all implicate “Compound 1” as the reactive intermediate that is responsible for the carbon-carbon scission reactivity of CYP19A1.Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2017-05-01The student, Abhinav Luthra, accepted the attached license on 2015-01-20 at 17:17.The student, Abhinav Luthra, submitted this Dissertation for approval on 2015-01-21 at 11:40.This Dissertation was approved for publication on 2015-02-25 at 15:46.DSpace SAF Submission Ingestion Package generated from Vireo submission #7691 on 2015-07-22 at 14:23:53Made available in DSpace on 2015-07-22T22:44:57Z (GMT). No. of bitstreams: 2
Luthra_Abhinav.pdf: 13338061 bytes, checksum: 5e39e44030991e9ba83c7f2a97dff272 (MD5)
license.txt: 4063 bytes, checksum: 4fe24235dd8d08f43e3ef345b01b0f88 (MD5)
Previous issue date: 2015-02-25Embargo set by: Seth Robbins for item 79949
Lift date: 2017-07-22T22:46:21Z
Reason: Author requested closed access (OA after 2yrs) in Vireo ETD systemLimited Restriction Lifted for Item 79949 on 2017-07-23T09:15:17Z
Mapping as a Tool for Communities
No full textiv, 34 p.This paper aims to analyze mapping as a process and as a tool for communities. In order to understand maps and mapping in the present and in the future, maps and mapping must be contextualized within a powered past and an understanding of maps as tools for mapmakers to construct or reconstruct power. Next, the author discusses the methods of community based mapping in order to understand mapping as a process and a relationship between communities and mapmakers. Furthermore, these processes of mapping are ways to build communities, negotiate power, and understand environment. Finally, the author argues that there are lessons for mapping with communities based the relationship between the mapmakers and the communities. Through these discussions, the author argues that mapmakers should evaluate their engagement with communities and strive to build capacity for mapping within the community. The ways that mapping is done with the community should be ways that build stronger communities, challenge power, and strengthen relationships between communities and their environments. Community based mapping is a tool to construct community based narratives and reconstruct power in the hands of the community members for the benefit of themselves and their community
Cash Rules Everything Around Me : Conceptualizing Universal Basic Income Within Capitalism and Across Political Ideology
No full textiv, 50 p.One of the most prominent ideas currently being tossed around in the public policy arena is that of a Universal Basic Income (UBI). Defined as "an income paid by a political community to its members on an individual basis, without means test or work requirement" (Van Parijs 2004, 8), UBI has become important to study for its potential to combat economic inequality and poverty in society. This piece analyzes UBI within the framework of our capitalist society and across a broad spectrum of differing political ideologies that support the proposal. In it, The author addresses the question: how does a UBI garner support from these wide-ranging ideologies? Part one of this work examines the benefits and points of contention surrounding a UBI, looking at the program's ability to lift people out of poverty, as well as its cost and potential effects on work. Part two analyzes the program from different points of view across the political spectrum, relating each proposal to its advocate's ideas about the welfare state. Part three looks at three different programs - the Alaska Permanent Fund, the casino dividends from the Eastern Band of Cherokee Indians in North Carolina, and the 1970s negative income tax experiments - to review empirical evidence, given that the programs are all similar to a UBI. Finally, the author concludes that no matter the costs or other barriers, we cannot pretend to care about ending poverty in this country unless we enact a UBI
A Look at Social, Economic and Structural Determinants that Shape and/or Influence Attitudes and Perspectives about the Environment in Highland Park, Los Angeles
No full textvii, 71 p.This research paper analyzes results from my research conducted in Highland Park, Los Angeles that had 22 respondents. The goal going into this project was to focus on the perspectives and attitudes towards climate change action and the environment in Highland Park, Los Angeles. Along with looking at which social determinants, if any, influence those attitudes and perspectives whether they be positive or negative influences. The author framed survey questions more towards asking how people perceive their surrounding natural and unnatural environment in their community. The research question: What are the social, structural and economic factors that either allow or constrain someone from thinking about the condition of the natural parts/environment of one's community? Results found that a majority of the participants (90%/20 out of 22) felt that they feel that they can help keep the natural parts of their community clean or in a good condition and 59% responded that taking care of the natural parts of the community, or keeping them in good condition, and attending to the man-made parts of one's life should be equally important. The sample size is small which keeps the author from running any significant statistical tests, but he provides a description of findings through his own observations
"Turn Around for Free College" : The Role Real Estate Agents and Agencies Play in the Process Of Gentrification in the Context ofthe Kalamazoo Promise
No full text61 p.The Kalamazoo Promise is a place-based scholarship program that attempts to shift the economic reality of Kalamazoo, Michigan. This research project analyzes the marketing strategies real estate agents and agencies implement in the home selling process through the construction of community. Real estate agents and agencies base the image of community on business/entertainment, family, and schools. The second half of this research focuses on the role real estate agents have in leveraging the Kalamazoo Promise to home buyers. The author calls for a continued focus on marketing strategies real estate agents and agencies implement when selling spaces in Kalamazoo, specifically in relation to the Kalamazoo Promise
The Perception of the Public : White Versus Black Police Officers
No full textv, 106 p.The author writes, “A lot of people say that white cops are racist and this is why their children are being killed by people that are supposed to protect them. I hear this a lot in Chicago, the city that I come from. By contrast, I never heard this about black cops. People's anger and frustration was mostly directed towards white cops.” For this reason, she decided to do research to examine the question: how do people perceive black versus white cops in and around Chicago? The author surveyed 85 people from different racial groups, categorized as black, white, and 'other.' Respondents answered 34 questions. The questions were based around six different sections: demographics, physical interactions with Black or White cops, perceptions of White or Black cops, Racial profiling, Dangers of being a Police officer, and General opinions about Police Officers. When analyzing the data, she used the chi-square text to determine which demographics was statistically significant to each question. Analysis of the survey data showed that age of the respondent was statistically significant most frequently in explaining the differences in responses to the survey questions
Fa 'a Samoa and China : The interface of indigenous socio-political systems, legacies of colonialism, and (re)imaginations of race in the independent state of Samoa
No full textv, 59 p.In an exploration of the way that race operates in Samoa, this qualitative research project studies the intersection of the Fa'a Samoa - the socio-political governance system of Samoa, the recent Chinese migration in the global context of China as an economic hegemon, and both colonial histories and modern legacies of race in Samoa. The author poses the research question: What is the impact of contemporary Chinese intervention on how race operates in Samoa for all members? In answering this question, a series of semi-formal interviews through the networks in and around the capital city of Apia were employed to collect (his)stories, opinions, and concerns in Samoa by folks that identify as Samoan. Out of conversations in a city and country transformed by the presence of the People's Republic of China, many participants elaborate on their own negotiations of the influx of new Chinese migrants and the consequent transformations of government, society, and family. In the most central indigenous social system in Samoa, the Fa 'a Samoa, continues to complexify race in Samoa through both its ability to subsume identities into the Samoan identity and give political power through its integration in the governmental structure. This project also explores the history of Chinese migrations in Samoa, producing differences of racialization for new Chinese migrants and Samoans with Chinese ancestry. The results and implications of this work points to the centrality of the Fa'a Samoa in the past, present, and future of Samoan racial (re)formations
Young Adults with Intellectual Disability Not Participating in Employment, Education or Daily Activity : Social Relationships and Experiences of Belonging
No full textA sense of belonging can be created through social relationships with other people but also through engagement in arenas such as work, school or leisure activities. The aim of the study was to examine the social relationships of young adults with intellectual disability who are not in employment, education or daily activity, as well as how these relationships are conditions for experiences of belonging. Semi-structured interviews with 10 individuals were conducted followed by thematic analysis. The results show that despite not having a daily occupation, the target group has meaningful social relationships that are informal (family, friends and online) and organized (professionals and leisure activities) in nature. These relationships contribute to a sense of belonging. Moreover, aspects related to having an intellectual disability, to being a young adult and their occupational status influence the groups’ relationships and experiences of belonging. © 2024 The Author(s).</p
