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Full-Text Articles in Medicine and Health Sciences

Combination Of Virb Binding Site Mutations To Evaluate Collective Impact On Icsp Promoter Activity In Shigella Flexneri, Pashtana Usufuzy, Juan C. Duhart, Maria I. Castellanos, Helen Wing Aug 2011

Combination Of Virb Binding Site Mutations To Evaluate Collective Impact On Icsp Promoter Activity In Shigella Flexneri, Pashtana Usufuzy, Juan C. Duhart, Maria I. Castellanos, Helen Wing

Undergraduate Research Opportunities Program (UROP)

Shigella flexneri is a gram-negative, invasive bacterial pathogen that afflicts the human colonic epithelium, causing shigellosis, an illness triggering severe dysentery. The World Health Organization cites the disease burden of shigellosis near 90 million episodes and 108,000 deaths per year.

The motility and spread of Shigella is modulated by icsP, a virulence gene. The transcription factor VirB positively regulates many virulence genes encoded by the Shigella virulence plasmid. Two distal binding sites of VirB have been shown to regulate the promoter activity of icsP, despite their location of more than 1 kb upstream of the transcription start site. Five VirB …


The Use Of Chloramines To Eradicate Quagga Mussel Larvae, Trea Lacroix, Kumud Acharya Aug 2011

The Use Of Chloramines To Eradicate Quagga Mussel Larvae, Trea Lacroix, Kumud Acharya

Undergraduate Research Opportunities Program (UROP)

Quagga Mussels, Dressenia bugensis, are a growing problem in the western United States, particularly in their ability to infest underwater infrastructures and clog water intake pipes and screens of power and treatment plants. Chlorine has been found to be the most effective chemical to get rid of veligers (planktonic larval form of quagga mussels) in the pipes. However, chlorine leaves a residue called trihalomethane, which is a carcinogen at higher concentrations. The purpose of this project is to test the effectiveness of an alternate chemical, chloramines (chlorine and ammonia), which leaves behind little to no residual trihalomethane. Upon experimentation with …


Defining The Role Of Nras In Melanoma Maintenance, Sravya T. Challa, Sheri L. Holmen Aug 2011

Defining The Role Of Nras In Melanoma Maintenance, Sravya T. Challa, Sheri L. Holmen

Undergraduate Research Opportunities Program (UROP)

The incidence of melanoma has increased 600 percent over the last four decades; it is the most rapidly increasing malignancy among young people in the United States and is currently the leading cause of cancer death in women aged 25- 29. If detected early, the disease is easily treated; however, once the disease has metastasized it is largely refractory to conventional therapies and is associated with a high mortality rate. The development of cancer from a pre-malignant primary tumor to a metastatic cancer that develops at secondary sites is a multi-step process, thought to require many genetic and epigenetic events …


Cell Migration Dynamics After Alteration Of Cell-Cell Contacts In Fibrosarcoma And Glioblastoma Cell Lines, Hassan S. Rizvi, Ronald K. Gary Aug 2011

Cell Migration Dynamics After Alteration Of Cell-Cell Contacts In Fibrosarcoma And Glioblastoma Cell Lines, Hassan S. Rizvi, Ronald K. Gary

Undergraduate Research Opportunities Program (UROP)

Cell migration is a vital component of metastasis. In this study, our intent was to study cell migration by alteration of the Wnt/GSK-3 Pathway. Since BeSO4 is a known GSK-3 kinase inhibitor, we hypothesized that this agent would cause cell migration to decrease as a result of β-catenin stabilization. Two human cell lines, HT-1080 (fibrosarcoma) and A172 (glioblastoma), were used to observe migration levels in the presence and absence of BeSO4. Our results show that cell migration is diminished for cells that were pre-treated with BeSO4, in comparison to the untreated (control) cells.


Regulation Of The Shigella Flexneri Icsp Gene And H-Ns Dependent Repression, Rosa Ojeda, Amanda Wigley, Dustin Harrison, Helen Wing Aug 2011

Regulation Of The Shigella Flexneri Icsp Gene And H-Ns Dependent Repression, Rosa Ojeda, Amanda Wigley, Dustin Harrison, Helen Wing

Undergraduate Research Opportunities Program (UROP)

The gram negative bacterium Shigella flexneri is known to cause dysentery in humans and primates. In order to help prevent the spread of shigellosis, gene regulation must be understood. Studies show that the virulence genes in S .flexneri are thermo regulated. At 30°C histone-like nucleoid structuring protein (H-NS) represses transcription of virulence genes and at 37°C VirB derepresses virulence genes. One of the genes that contribute to the virulence of S. flexneri is icsP. My project focuses on the regulation of the S. flexneri icsP gene and has two main goals. The first is to identify the sequence of H-NS …


Construction And Use Of A Calorimeter To Estimate The Anaerobic Contributions To Metabolism, Mark S. Burger, Frank Van Breukelen Aug 2010

Construction And Use Of A Calorimeter To Estimate The Anaerobic Contributions To Metabolism, Mark S. Burger, Frank Van Breukelen

Undergraduate Research Opportunities Program (UROP)

Metabolism is derived from the Greek word metabole which translates to change. Metabolism is the sum total of chemical reactions that take place in an organism. Some reactions are exothermic (heat-producing) whereas others are endothermic (heat-absorbing). By measuring heat production (calorimetry), one can estimate metabolic rate. Historically, such measurements of direct calorimetry were difficult. As a result, most studies utilize indirect calorimetry wherein oxygen consumption and/or carbon dioxide production are measured. One limitation to this approach is that anaerobic metabolism is ignored. No commercially-available calorimeter is available for whole animal metabolic studies. We hypothesized that small rodent hibernators may experience …


Undergraduate Research Opportunities Program 2010, University Of Nevada, Las Vegas Aug 2010

Undergraduate Research Opportunities Program 2010, University Of Nevada, Las Vegas

Undergraduate Research Opportunities Program (UROP)

The Undergraduate Research Opportunities Program (UROP) cultivates and supports research partnerships and invites undergraduates to work as the junior colleagues of faculty. The program offers the opportunity to work on cutting edge research—whether you join established research projects or pursue your own ideas. As participants, undergraduates engage in each phase of standard research activity: developing research plans, writing proposals, conducting research, analyzing data. and presenting research results in oral and written form. The projects take place over the summer, and research can be done in any academic department or interdisciplinary laboratory. Projects can last for an entire semester, and many …


Pdest Fg12-Cmv Dsred Vector, Jarod Wolffis, Sheri L. Holmen Aug 2009

Pdest Fg12-Cmv Dsred Vector, Jarod Wolffis, Sheri L. Holmen

Undergraduate Research Opportunities Program (UROP)

Melanoma is the most rapidly increasing malignancy among young people in the United States. If detected early, the disease is easily treated; however, once the disease has metastasized it is largely refractory to conventional therapies and is associated with a high mortality rate. The development of human cancer from a pre-malignant primary tumor to a metastatic lesion that develops at secondary sites is thought to be a multi-step process, requiring many genetic and epigenetic events that provide a growth advantage to cells. It is still unclear which of the many genetic changes in human cancers are required for metastasis. Therefore, …


Expression Of An Alternate Splice Form Of Bmi-1 In Multiple Myeloma, Adam Austin, Kristine Veys, Debbie Wong, James Tung Aug 2009

Expression Of An Alternate Splice Form Of Bmi-1 In Multiple Myeloma, Adam Austin, Kristine Veys, Debbie Wong, James Tung

Undergraduate Research Opportunities Program (UROP)

The concept of “tumor stem cells” has garnered much attention in the last few years. Tumor stem cells are believed to exist among a heterogeneous group of cells that constitute a tumor. These tumor stem cells often express genes that are important for stem cell function, cell division, and maintenance of pluripotent state in stem cells. Stem cell or stem cell maintenance genes such as SALL 4 and Bmi-1 are often seen in these cancer cells and contribute to self-renewing divisions and cancer cell survival. In particular, high expression of Bmi-1 (B lymphoma mouse Moloney leukemia virus insertion region), a …


Survival Of Shigella Flexneri In Swimming Pool Water, Monique Gomez, Helen J. Wing Aug 2009

Survival Of Shigella Flexneri In Swimming Pool Water, Monique Gomez, Helen J. Wing

Undergraduate Research Opportunities Program (UROP)

Shigellosis is a disease caused by the pathogenic bacterium Shigella flexneri. The bacterium causes bloody diarrheadiarrhea, fever and abdominal pain. Infections can be and may cause fatal. . The disease may also cause bloody diarrhea and intense intestinal crampings. In the United States, there have been many outbreaks of shigellosis have been traced back to associated with inadequately disinfectedchlorinated public swimming pools and wading pools. These outbreaks of sShigellosis are most commonly seen among small children who play in these pools. . My goal is to determine how well Shigella survives in freshly chlorinated pool water and in pool water …


Undergraduate Research Opportunities Program, University Of Nevada Las Vegas, College Of Sciences Aug 2009

Undergraduate Research Opportunities Program, University Of Nevada Las Vegas, College Of Sciences

Undergraduate Research Opportunities Program (UROP)

No abstract provided.


Characterization Of The Omptin Protease, Ompt, In Escherichia Coli, Amanda Yates, Eun-Hae Kim, Helen Wing Aug 2008

Characterization Of The Omptin Protease, Ompt, In Escherichia Coli, Amanda Yates, Eun-Hae Kim, Helen Wing

Undergraduate Research Opportunities Program (UROP)

Omptins are outer membrane proteases found in gram negative bacteria that cause diseases in humans, such as pathogenic Escherichia coli, Shigella flexneri, Salmonella typhimurium, and Yersinia pestis. Bacterial species that express omptins cause diseases such as highly fatal plague and severe diarrhea and dysentery. The genes that encode these proteases are ompT, icsP, pgtE, and pla, respectively. These proteases are highly related in structure and share approximately 50% sequence identity. In S. flexneri, IcsP has been shown to cleave a key virulence determinant, IcsA (Egile et al., 1997). IcsA recruits host actin and allows for intracellular movement within host cells …


The Effects Of Host Physiological Conditions On The Expression Of Icsp In Shigella Flexneri, Karen Levy, Helen Wing Aug 2008

The Effects Of Host Physiological Conditions On The Expression Of Icsp In Shigella Flexneri, Karen Levy, Helen Wing

Undergraduate Research Opportunities Program (UROP)

Shigella flexneri is a gram-negative bacterium capable of causing diarrhea and dysentery known as shigellosis. It is estimated there are 167.4 million shigellosis episodes throughout the world each year causing 1.1 million deaths. Shigella invades cells in the lower intestine through an induced phagocytosis. Once in the cytoplasm, bacteria move from one cell to another using actin-based motility. The Shigella outer membrane protease IcsP regulates actin-based motility and cell-to-cell spread by cleaving the actin assembly protein IcsA from the bacterial cell surface. We hypothesize that IcsP may serve additional functions during infection. By examining which environmental signals trigger icsP expression, …