Digital Commons Network^™

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, …

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 …

Relationship Of Lactobacillus Casei To Prevention Of Antibiotic Associated Diarrhea Due To Clostridium Difficile, Kayal K. Chandramohan

All-Inclusive List of Electronic Theses and Dissertations

The purpose of this research was to study the effectiveness of Lactobacillus casei in preventing the occurrence of antibiotic associated diarrhea related to Clostridium difficile. Twenty-six patients, above the age of sixty years, who were prescribed antibiotic therapy and admitted to the Rehabilitation or Orthopedics Units at Union Hospital and who met the eligibility criteria were recruited for the study. Equal numbers of patients (13 in each group) were assigned to the Control and the Experimental group based on their admission date to the hospital and their willingness to consume a probiotic yogurt type drink. The patients in the experimental …

El Virus De La Diarrea Viral En Bovinos Criollos De La Provincia De Melgar, Puno, Q. Richard Quispe, Ccama Albert S., Hermelinda G. Rivera, Mariluz Araínga

Journal Articles: Pharmacology & Experimental Neuroscience

The prevalence of bovine viral diarrhea virus (BVDV) infection in 347 evaluated was criollo cattle of both sexes and older than 6 months of age in small herds of the province of Melgar, Puno. Serum samples were tested for antibodies against BVDV using the viral neutralization test. The 48.7 ± 0.1% (166/347) of the samples had antibodies against BVDV. Animals carrying on the virus, virus were not detected. Antibodies were detected in all sampled herds and the prevalence varied from 15.7 to 94.1%. Antibodies titers varied from 2 to >256, showing that BVDV infection is widespread in the local cattle …

Pcr-Based Assay Using Occult Blood Detection Cards For Detection Of Diarrheagenic Escherichia Coli In Specimens From Us Travelers To Mexico With Acute Diarrhea, Kevin A Grimes, Jamal A Mohamed, Herbert L Dupont, Ranjit S Padda, Zhi-Dong Jiang, Jose Flores, Jaime Belkind-Gerson, Francisco G Martinez-Sandoval, Pablo C Okhuysen

Faculty, Staff and Student Publications

Large field studies of travelers' diarrhea for multiple destinations are limited by the need to perform stool cultures on site in a timely manner. A method for the collection, transport, and storage of fecal specimens that does not require immediate processing and refrigeration and that is stable for months would be advantageous. This study was designed to determine if enterotoxigenic Escherichia coli (ETEC) and enteroaggregative E. coli (EAEC) DNA could be identified from cards that were processed for the evaluation of fecal occult blood. U.S. students traveling to Mexico during 2005 to 2007 were monitored for the occurrence of diarrheal …

The Role Of Extracellular Matrix And Matrix-Degrading Proteases In Neonatal Hypoxic-Ischemic Injury, Christopher C. Leonardo

USF Tampa Graduate Theses and Dissertations

Improvements in medical care over recent decades have increased the number of premature and low birth weight infants that survive hypoxic-ischemic (H-I) insults. Because there is a rising incidence in diseases associated with these events, it is critical to develop effective therapies to treat the various resulting neuropathies. Extracellular matrix constitutes the majority of brain parenchyma. Lecticans and matrix-degrading proteases including ADAMTSs (a disintegrin and metalloproteinase with thrombospondin repeats) and matrix metalloproteinases (MMPs) exert effects on cell viability and may be associated with either protective or destructive processes after H-I. Both ADAMTSs (Cross et al. 2006; Tian et al. 2007) …

Response Of Endothelial Cells To Stressors: The Impact Of Aging And Diabetes, Katie Mclellan

Loma Linda University Electronic Theses, Dissertations & Projects

Preliminary research indicates there is some impairment of the endothelial cells to respond to single stressors such as local heat, shear stress, and global heat in older people and people who have diabetes. The response of the skin blood flow to local heat is an indicator of the endothelial cells ability to cope with stress. In addition, factors such as thicker subcutaneous fat and skin moisture may impair the skin’s ability to dissipate heat. For older people and people with diabetes, this endothelial dysfunction may cause an even more diminished response to multiple stressors. However, no studies have examined the …

Novel Binding Domains Mediate Binding Of Hpv 16 E6 To Fadd And Procaspase 8, Sandy S. Tungteakkhun

Loma Linda University Electronic Theses, Dissertations & Projects

To evade the host response to infection, viruses have developed means to survive and propagate. HPV 16, a causative agent of cervical cancer and of some cases of oropharyngeal cancers, is one example. We have reported that the early viral protein E6 binds to proteins necessary for propagation of the apoptotic signal following receptor/ligand interactions, such as those mediated by FADD DED and procaspase 8 DED. E6 expression leads to the dose-dependent accelerated degradation of FADD and the protection of E6-expressing cells from Fas-induced apoptosis. Surprisingly, the splice isoforms of E6, E6_large and E6*, affect the stability of procaspase …

Mechanisms Of T Helper Cell Modulation In A Simulated Space Radiation Environment, Asma Rizvi

Loma Linda University Electronic Theses, Dissertations & Projects

Exposure to solar particle events (SPEs) poses the most serious threat to astronaut health. Due to this radiation environment, exploration of the solar system beyond Earth’s orbit entails many risks for the crew on these deep space missions. Depression or dysfunction of the immune system is a major concern due to its high radio-sensitivity; potential consequences include overwhelming infection, development of cancer, fibrosis, and poor wound healing. Astronauts are also exposed to low dose/low dose rate (LDR) radiation. A three month stay at the international space station exposes them to ~ 0.05 Gy of radiation.

C57BL/6 mice received LDR gamma-radiation …

Food Restriction Compromises Immune Memory In Deer Mice (Peromyscus Maniculatus) By Reducing Spleen-Derived Antibody-Producing B Cell Numbers, Lynn B. Martin, Kristen J. Navara, Michael T. Bailey, Chelsea R. Hutch, Nicole D. Powell, John F. Sheridan, Randy J. Nelson

Integrative Biology Faculty and Staff Publications

Immune activity is variable in many wild animals, despite presumed strong selection against immune incompetence. Much variation may be due to changes in prevalence and abundance of pathogens (and/or their vectors) in time and space, but the costs of immune defenses themselves may also be important. Induction of immune activity often increases energy and protein expenditure, sometimes to the point of compromising fitness. Whether immune defenses are expensive to maintain once they are generated, however, is less well appreciated. If so, organisms would face persistent challenges of allocating resources between immunity and other expensive physiological processes, which would mandate trade-offs. …

Maternal Cocaine Administration In Mice Alters Dna Methylation And Gene Expression In Hippocampal Neurons Of Neonatal And Prepubertal Offspring, Svetlana I. Novikova, Fang He, Jie Bai, Nicholas J. Cutrufello, Michael S. Lidow, Ashiwel S. Undieh

Publications and Research

Previous studies documented significant behavioral changes in the offspring of cocaine-exposed mothers. We now explore the hypothesis that maternal cocaine exposure could alter the fetal epigenetic machinery sufficiently to cause lasting neurochemical and functional changes in the offspring. Pregnant CD1 mice were administered either saline or 20 mg/kg cocaine twice daily on gestational days 8–19. Male pups from each of ten litters of the cocaine and control groups were analyzed at 3 (P3) or 30 (P30) days postnatum. Global DNA methylation, methylated DNA immunoprecipitation followed by CGI2 microarray profiling and bisulfite sequencing, as well as quantitative real-time RT-PCR gene expression …

Drug Resistance In Malaria: A Peruvian Research Experience, Ryan Haley

Inquiry Journal 2008

No abstract provided.

Health State Valuation In Mild To Moderate Cognitive Impairment: Feasibility Of Computer-Based, Direct Patient Utility Assessment, Neal V. Dawson, Mendel E. Singer, Marian B. Patterson, Susie A. Sami, Iahn Gonsenhouser, Heather A. Lindstrom, Kathleen A. Smyth, Melissa Barber Butson, Peter J. Whitehouse

Faculty Scholarship

Background. Most patients with dementia will, at some point, need a proxy health care decision maker. It is unknown whether persons with various degrees of cognitive impairment can reliably report their health-related preferences. Methods. The authors performed health state valuations (HSVs) of current and hypothetical future health states on 47 pairs of patients with mild to moderate cognitive impairment and their caregivers using computer-based standard gamble, time tradeoff, and rating scale techniques. Results. Patients' mean (SD) age was 74.6 (9.3) years. About half of the patients were women (48%), as were most caregivers (73%), who were on average younger (mean …

Renin Inhibition Reduces Hypercholesterolemia-Induced Atherosclerosis In Mice, Hong Lu, Debra L. Rateri, David L. Feldman, Richard Charnigo, Akiyoshi Fukamizu, Junji Ishida, Elizabeth Grace Oesterling, Lisa A. Cassis, Alan Daugherty

Saha Cardiovascular Research Center Faculty Publications

The role of the renin angiotensin system (RAS) in atherosclerosis is complex because of the involvement of multiple peptides and receptors. Renin is the rate-limiting enzyme in the production of all angiotensin peptides. To determine the effects of renin inhibition on atherosclerosis, we administered the novel renin inhibitor aliskiren over a broad dose range to fat-fed LDL receptor-deficient (Ldlr^-/-) mice. Renin inhibition resulted in striking reductions of atherosclerotic lesion size in both the aortic arch and the root. Subsequent studies demonstrated that cultured macrophages expressed all components of the RAS. To determine the role of macrophage-derived angiotensin in …

Clinical And Microbiological Aspects Of Linezolid Resistance Mediated By The Cfr Gene Encoding A 23s Rrna Methyltransferase, Cesar A Arias, Martha Vallejo, Jinnethe Reyes, Diana Panesso, Jaime Moreno, Elizabeth Castañeda, Maria V Villegas, Barbara E Murray, John P Quinn

Faculty, Staff and Student Publications

The cfr (chloramphenicol-florfenicol resistance) gene encodes a 23S rRNA methyltransferase that confers resistance to linezolid. Detection of linezolid resistance was evaluated in the first cfr-carrying human hospital isolate of linezolid and methicillin-resistant Staphylococcus aureus (designated MRSA CM-05) by dilution and diffusion methods (including Etest). The presence of cfr was investigated in isolates of staphylococci colonizing the patient's household contacts and clinical isolates recovered from patients in the same unit where MRSA CM-05 was isolated. Additionally, 68 chloramphenicol-resistant Colombian MRSA isolates recovered from hospitals between 2001 and 2004 were screened for the presence of the cfr gene. In addition to erm(B), …

Psychiatric Outcomes In A Resident-Run Multidisciplinary Hepatitis C Clinic, Nicole M. Agostino Do, Edward Norris Md, Fapm, Joseph L. Yozviak Do, Facp, Charles M. Brooks Md, Eric J. Gertner Md, Mph, Michael Kaufmann Md

Department of Medicine

No abstract provided.

Radiation-Induced Glutamate Transport Alterations In Neuron-Astrocyte Coupling, Martha Celia Sanchez

Loma Linda University Electronic Theses, Dissertations & Projects

Exposure of the central nervous system (CNS) to ionizing radiation is known to result in behavioral, cognitive, and motor deficits - effects similar to those seen in many neurodegenerative disorders. Neurons and astrocytes, two principal cell types in the brain, coexist as an interdependent metabolic unit via the neurotransmitter glutamate. Disruption of this metabolic coupling would have widespread effects within the CNS, therefore it is hypothesized that ionizing radiation impairs glutamate transport and metabolism, and increases oxidative stress, ultimately impairing neuron-astrocyte coupling. We propose to investigate the mechanism and determine the impetus for radiation-induced neurotoxicity by measuring the temporal sequence …

Incorporating Ethnicity Into Genetic Risk Assessment For Alzheimer Disease: The Reveal Study Experience, Peter J. Whitehouse, Melissa Barber Butson

Faculty Scholarship

PURPOSE: To describe how investigators in a multisite randomized clinical trial addressed scientific and ethical issues involved in creating risk models based on genetic testing for African American participants. METHODS: The following informed our decision whether to stratify risk assessment by ethnicity: evaluation of epidemiological data, appraisal of benefits and risks of incorporating ethnicity into calculations, and feasibility of creating ethnicity-specific risk curves. Once the decision was made, risk curves were created based on data from a large, diverse study of first-degree relatives of patients with Alzheimer disease. RESULTS: Review of epidemiological data suggested notable differences in risk between African …

Method For Treating A Viral Infection Related Or A Chemical Toxin Related Hepatic Injury With Deltorphin D, Peter R. Oeltgen, Paul D. Bishop, Craig J. Mcclain, Shirish Barve

Pathology and Laboratory Medicine Faculty Patents

A method of modulating cytokine mediated hepatic injury by administering compound-D SEQ ID NO:1 to a mammal. A concentration of the compound in the range of about 0.5 mg/kg to about 20 mg/kg in a physiologically acceptable formulation blocks a cytokine cascade. A therapeutic method of modulating cytokine mediated acute inflammatory, trauma induced and toxin induced hepatic injury, particularly via tumor necrosis factor modulation, is thus disclosed.

Novel Role Of Antioxidant-1 (Atox1) As A Copper-Dependent Transcription Factor Involved In Cell Proliferation, S. Itoh, H. W. Kim, O. Nakagawa, K. Ozumi, Susan M. Lessner, H. Aoki, K. Akram, R. D. Mckinney, M. Ushio-Fukai, T. Fukai

Faculty Publications

Copper plays a fundamental role in regulating cell growth. Many types of human cancer tissues have higher copper levels than normal tissues. Copper can also induce gene expression. However, transcription factors that mediate copper-induced cell proliferation have not been identified in mammals. Here we show that antioxidant-1 (Atox1), previously appreciated as a copper chaperone, represents a novel copper-dependent transcription factor that mediates copper-induced cell proliferation. Stimulation of mouse embryonic fibroblasts (MEFs) with copper markedly increased cell proliferation, cyclin D1 expression, and entry into S phase, which were completely abolished in Atox1^-/- MEFs. Promoter analysis and EMSA revealed that copper …

Reproductive Health Training Of Turkish Soldiers From Certain Risk Groups, Ercan Göçgeldi̇, Bi̇lal Bakir, Aygül Akyüz, Mahi̇r Güleç, Tülay Kaya, Sadetti̇n Güngör, Meti̇n Hasde

Turkish Journal of Medical Sciences

Aims: The 2003 Turkey Demographic and Health Survey (TDHS-2003) pointed out significant differences between East Anatolia and the other regions of Turkey. Some studies carried out among Turkish soldiers have underlined the need for more information on Reproductive Health (RH) issues for soldiers with lower educational level and coming from the eastern region of Turkey. Since marriage in Turkey is very important from a demographic perspective, this study has attempted to determine prevalence of marriage and certain characteristics of married soldiers who were involved in the RH courses. The aim of the study was to determine the results of RH …

Second-Hand Tobacco Smoke And Acute Eosinophilic Pneumonia, Zekai̇ Avci, Bülent Ali̇oğlu, Emel Özyürek, Namik Özbek

Turkish Journal of Medical Sciences

We present the case reports of two children with a parasitic infestation associated with hypereosinophilia. One of those patients, who had been exposed to excessive second-hand tobacco smoke, was diagnosed as having acute eosinophilic pneumonia. The second patient had neither a history of exposure to second-hand smoke nor a prior diagnosis of acute eosinophilic pneumonia. We suggest that passive smoking may trigger acute eosinophilic pneumonia, a condition that develops frequently in children living in countries in which parasitic infestations and tobacco smoking are prevalent.

Cause Of Fever In A Case With End-Stage Renal Disease: Splenic Marginal Zone Lymphoma, Ramazan Çeti̇nkaya, İlhami̇ Ki̇ki̇, Abdullah Uyanik, Mustafa Keleş, Bülent Aydinli, Fazli Erdoğan, Nesri̇n Gürsan, Abdul Meci̇t Kantarci

Turkish Journal of Medical Sciences

Splenic marginal zone lymphomas (SMZL) are rare tumors arising from B-cells, accounting for approximately 1% of all lymphomas. An accompanying lymphoma is uncommon in patients who have chronic renal failure and undergo hemodialysis. We present herein a 35-year-old male hemodialysis patient admitted with fever, abdominal pain, and splenomegaly, diagnosed with SMZL. In our investigations in the English literature, we did not observe any SMZL case among hemodialysis patients. Fever may emerge due to different causes in chronic hemodialysis patients, primarily infections. In hemodialysis patients presenting with fever, lymphoma and other malignant diseases should be considered.

Tissue Engineering The Motoneuron To Muscle Segment Of The Stretch Reflex Arc Circuit Utilizing Micro-Fabrication, Interface Design And Defined Medium Formulation, Mainak Das

Electronic Theses and Dissertations

The stretch reflex circuit is one of the most primitive circuits of mammalian system and serves mainly to control the length of the muscle. It consists of four elements: the stretch sensor (muscle spindle/ intrafusal fiber lie parallel between extrafusal, contractile musculature), extrafusal muscle fiber, sensory neuron and motoneuron. The basic principle of the stretch reflex arc circuit is as follows: whenever there is a sudden stretch in a muscle, it needs to compensate back to its original length so as to prevent any kind of injury. It performs this compensation process using a simple negative feed back circuit called …

Enzymatic Processing Of Amelogenin During Continuous Crystallization Of Apatite, Vuk Uskoković, M.-K. Kim, W. Li, S. Habelitz

Pharmacy Faculty Articles and Research

Dental enamel forms through a protein-controlled mineralization and enzymatic degradation with a nanoscale precision that new engineering technologies may be able to mimic. Recombinant fulllength human amelogenin (rH174) and a matrix-metalloprotease (MMP-20) were employed in a pHstat titration system that enabled a continuous supply of calcium and phosphate ions over several days, mimicking the initial stages of matrix processing and crystallization in enamel in-vitro. Effects on the self-assembly and crystal growth from a saturated aqueous solution containing 0.4 mg/ml rH174 and MMP-20 with the weight ratio of 1:1000 with respect to rH174 were investigated. A transition from nanospheres to fibrous …

Gliotoxin Production In Aspergillus Fumigatus, Susan Musyimi

Theses and Dissertations

Aspergillus fumigalus is a ubiquitous fungus that causes an infection called aspergillosis in immune-compromised surgery patients (Latge, 2001, 384; Bok et al. 2006). Aspergillosis cases have increased in the past decade due to the increasing number of patients undergoing immunosuppressive therapy and receiving organ transplants (Bok et al. 2006). Although there is still disagreement as to the causative agent of the symptoms accompanying aspergillosis, many scientists suspect that the compound, gliotoxin, plays a major role, hi this study, we compared the amounts of gliotoxin produced from clinical and environmental isolates of A. fumigatus. We hypothesized that the amount of gliotoxin …

Assessment Of Mental Health Of University Students With Ghq-12, Sarp Üner, Hi̇lal Özcebe, T. Gökhan Telatar, Sabahat Tezcan

Turkish Journal of Medical Sciences

Aims: The aim of this study was to assess the mental health status of university students and the factors affecting their mental health. Materials and Methods: The universe of the study consisted of a total of 8407 students enrolled as first- or third-year students of a university. The study sample was determined by using the ``sampling size where the population in universe is known´´ formula. The study questionnaire was designed to include questions regarding some sociodemographic characteristics and the General Health Questionnaire (GHQ)-12. Data were analyzed by SPSS 15.0, and binary logistic regression forward selection method was used to determine …

Mixed Medullary-Follicular Thyroid Carcinoma : A Report Of Two Cases, Özge Han, Tuba Ünal, Selda Seçki̇n, Sezer Kulaçoğlu

Turkish Journal of Medical Sciences

Mixed medullary-follicular carcinoma is an uncommon tumor of the thyroid. It is characterized by histological and immunohistochemical features of both follicular and parafollicular C cells. We report two female patients, aged 26 and 78 years, with mixed medullary-follicular carcinoma. Histologically, the tumors are composed of follicular carcinoma areas and solid nests of polygonal cells consistent with medullary carcinoma. Immunohistochemically, thyroglobulin and calcitonin positivity was detected. Precise diagnosis of mixed medullary-follicular carcinoma is essential for accurate treatment and follow-up.

Resident Physicians In Turkey: Results Of A Survey Of 1069 Residents From 11 Provinces, Erhan Aysan, Gürol Köroğlu, Vi̇ldan Türkeli̇, Abdullah Özgönül, Ali̇ Özyaşar, Çağri Gülümser, Kemal Kiliç, Türker Ertürk, Özhan Özdemi̇r, Ahmet Hamdi̇ Alpaslan, Savaş Bayrak

Turkish Journal of Medical Sciences

Aims: To determine the problems, expectations and objectives of resident physicians in Turkey and to provide a contribution to the development and amendment of the residency program. Background: Residency varies considerably in accordance with factors like teaching staff, the institution and government policies. If characteristics, problems, expectations and objectives of resident physicians are stated and known, development and amendment of residency programs will be both easier and faster. Materials and Methods: A 50-question survey was completed by a randomly selected 1069 resident physicians from 15 university and 12 teaching hospitals in 11 provinces (İstanbul-503, Ankara-116, İzmir-86, Erzurum-71, Sivas-60, Bolu-49, Bursa-49, …

Searching For The Majority: Algorithms Of Voluntary Control, Jin Fan, Kevin G. Guise, Xun Liu, Hongbin Wang

Faculty, Staff and Student Publications

Voluntary control of information processing is crucial to allocate resources and prioritize the processes that are most important under a given situation; the algorithms underlying such control, however, are often not clear. We investigated possible algorithms of control for the performance of the majority function, in which participants searched for and identified one of two alternative categories (left or right pointing arrows) as composing the majority in each stimulus set. We manipulated the amount (set size of 1, 3, and 5) and content (ratio of left and right pointing arrows within a set) of the inputs to test competing hypotheses …