Medicine and Health Sciences Commons^™

Decreasing Barriers For Teens: Evaluation Of A New Teenage Pregnancy Prevention Strategy In School-Based Clinics, Abbey C. Sidebottom, Amanda Birnbaum, Sarah S. Nafstad

Department of Public Health Scholarship and Creative Works

Sidebottom et al seek to evaluate the effects of the change in distribution systems on students' receipt of requested contraceptives and demand for contraceptive school-based clinics (SBC). The result of the study reveals that the average number of requests per student was higher under the voucher system, possibly as a consequence of expires vouchers resulting in repeated requests. The findings also suggest that SBCs could go a step further in reducing adolescents' barriers to accessing contraceptives by adopting an on-site direct delivery system..

Interpreting Hemoglobin And Water Concentration, Oxygen Saturation, And Scattering Measured In Vivo By Near-Infrared Breast Tomography, Subhadra Srinivasan, Brian W. Pogue, Shudong Jiang, Hamid Dehghani, Christine Kogel, Sandra Soho, Jennifer J. Gibson, Tor D. Tosteson, Steven P. Poplack, Keith D. Paulsen

Dartmouth Scholarship

Near-infrared spectroscopic tomography was used to measure the properties of 24 mammographically normal breasts to quantify whole-breast absorption and scattering spectra and to evaluate which tissue composition characteristics can be determined from these spectra. The absorption spectrum of breast tissue allows quantification of (i) total hemoglobin concentration, (ii) hemoglobin oxygen saturation, and (iii) water concentration, whereas the scattering spectrum provides information about the size and number density of cellular components and structural matrix elements. These property data were tested for correlation to demographic information, including subject age, body mass index, breast size, and radiographic …

Waddington’S Widget: Hsp90 And The Inheritance Of Acquired Characters, Douglas M. Ruden, Mark D. Garfinkel, Vincent E. Sollars, Xiangyi Lu

Biochemistry and Microbiology

Conrad Waddington published an influential model for evolution in his 1942 paper, Canalization of Development and Inheritance of Acquired Characters. In this classic, albeit controversial, paper, he proposed that an unknown mechanism exists that conceals phenotypic variation until the organism is stressed. Recent studies have proposed that the highly conserved chaperone Hsp90 could function as a “capacitor,” or an “adaptively inducible canalizer,” that masks silent phenotypic variation of either genetic or epigenetic origin. This review will discuss evidence for, and arguments against, the role of Hsp90 as a capacitor for morphological evolution, and as a key component of what …

Topographical Expression Of Class Ia And Class Ii Phosphoinositide 3-Kinase Enzymes In Normal Human Tissues Is Consistent With A Role In Differentiation, Soha Salama El Sheikh, Jan Domin, Prakitpunthu Tomtitchong, Paul Abel, Gordon Stamp, El-Nasir Lalani

Department of Pathology and Laboratory Medicine

Background: Growth factor, cytokine and chemokine-induced activation of PI3K enzymes constitutes the start of a complex signalling cascade, which ultimately mediates cellular activities such as proliferation, differentiation, chemotaxis, survival, trafficking, and glucose homeostasis. The PI3K enzyme family is divided into 3 classes; class I (subdivided into IA and IB), class II (PI3K-C2α, PI3K-C2β and PI3K-C2γ) and class III PI3K. Expression of these enzymes in human tissue has not been clearly defined.

Methods: In this study, we analysed the immunohistochemical topographical expression profile of class IA (anti-p85 adaptor) and class II PI3K (PI3K-C2α and PI3K-C2β) enzymes in 104 formalin-fixed, paraffin embedded …

Tomographic Reconstruction Of Treponemal Cytoplasmic Filaments Reveals Novel Bridging And Anchoring Components, Jacques Izard, Bruce F. Mcewen, Rita M. Barnard, Thomas Portuese, William A. Samsonoff, Ronald J. Limberger

Department of Food Science and Technology: Faculty Publications

An understanding of the involvement of bacterial cytoplasmic filaments in cell division requires the elucidation of the structural organization of those filamentous structures. Treponemal cytoplasmic filaments are composed of one protein, CfpA, and have been demonstrated to be involved in cell division. In this study, we used electron tomography to show that the filaments are part of a complex with a novel molecular organization that includes at least two distinct features decorating the filaments. One set of components appears to anchor the filaments to the cytoplasmic membrane. The other set of components appears to bridge the cytoplasmic filaments on the …

Il-7 Enhances Peripheral T Cell Reconstitution After Allogeneic Hematopoietic Stem Cell Transplantation., Onder Alpdogan, Stephanie J Muriglan, Jeffrey M Eng, Lucy M Willis, Andrew S Greenberg, Barry J Kappel, Marcel R M Van Den Brink

Department of Medical Oncology Faculty Papers

We used clinically relevant murine allogeneic bone marrow transplantation (BMT) models to study the mechanisms by which IL-7 administration can improve posttransplant peripheral T cell reconstitution. After transplant we could distinguish two populations of mature donor T cells: (a) alloreactive T cells with decreased expression of CD127 (IL-7 receptor alpha chain) and (b) nonalloreactive T cells, which express CD127 and undergo homeostatic proliferation. IL-7 administration increased the homeostatic proliferation of nonalloreactive T cells, but had no effect on alloreactive T cells and the development of graft-versus-host disease. Allogeneic transplant of purified hematopoietic stem cells and adoptive transfer of thymocytes into …

Immortalized Epithelial Cells From Human Autosomal Dominant Polycystic Kidney Cysts, Mahmoud Loghman-Adham, Surya M. Nauli, Carlos E. Soto, Barbara Kariuki, Jing Zhou

Pharmacy Faculty Articles and Research

Autosomal dominant polycystic kidney disease (ADPKD) is the result of mutations in one allele of the PKD1 or PKD2 genes, followed by "second hit" somatic mutations of the other allele in renal tubule cells. Continued proliferation of clonal cells originating from different nephron segments leads to cyst formation. In vitro studies of the mechanisms of cyst formation have been hampered by the scarcity of nephrectomy specimens and the limited life span of cyst-derived cells in primary culture. We describe the development of a series of immortalized epithelial cell lines from over 30 individual renal cysts obtained from 11 patients with …

The Benefits Of Breastfeeding: An Introduction For Health Educators, Sheila G. J. Clark, Timothy J. Bungum

Environmental & Global Health Faculty Research

Currently 16% of Americans breastfeed their children for at least 12 months as recommended by the AAP, which is well below the HP 2010 goal of 25%. Breastfed infants receive benefits that can improve their health throughout their lives. The benefits of breastfeeding for children include increased resistance to infectious diseases, such as gastroenteritis, respiratory tract infections, and ear infections. Breastfed children also display lower rates of chronic diseases including diabetes, obesity, asthma, and leukemia. The choice to breastfeed results in economic benefits from lower health care costs and from reduced spending on infant formula. The Healthy People 2010 targets …

Prediction Of Fetal Sheep Brain Metabolic Rate During Hypoxia And Cord Occlusion, Adam D. Hickerson

Loma Linda University Electronic Theses, Dissertations & Projects

Many investigators have observed that fetal and neonatal animals are remarkably tolerant to hypoxia compared to the adult. The precise mechanisms however are still unclear. In order to better characterize the hemodynamic and metabolic responses of the fetal brain to hypoxic stress, we have designed a mathematical model to predict tissue oxygenation and metabolic rate of the fetal brain during both moderate hypoxia and severe asphyxia.

The model is based on the Krogh cylinder concept and is similar to one previously published by our lab. Several new concepts were added including the ability to run the model over time using …

Validation Of A Serotonin Checklist In A Parkinson’S Disease Population, Kelly Diane Darby-Holder

Loma Linda University Electronic Theses, Dissertations & Projects

Although the distinctive pathological marker of Parkinson’s Disease is the progressive death of neurons that produce dopamine, there are also alterations in the production of quantities of other neurotransmitters, such as norepinephrine and serotonin that contribute to the disease. Parkinson’s Disease (PD) can be divided into two distinct classes based on the manifestation of motor symptoms, Type A and Type B Parkinson’s Disease. Type B PD patients often manifest symptoms in which serotonin deficiency plays an important role, which often includes a history of depression. Within the brain and spinal cord serotonin has wide spread projections, acting as an important …

Sart Influences Sars Expression In Staphylococcus Aureus, Katherine A. Schmidt, Adhar C. Manna, Ambrose L. Cheung

Dartmouth Scholarship

Staphylococcus aureus is a gram-positive pathogen that is capable of expressing a variety of virulence proteins in response to environmental signals. Virulence protein expression in S. aureus is controlled by a network of regulatory loci including sarA and agr. The sarA/agr network is associated with the expression of cell wall-associated adhesins during exponential growth and the expression of secreted enzymes and toxins in the transition to post-exponential growth. A number of sarA homologs, including sarT and sarS, have been identified in the S. aureus genome. Previous studies have shown that sarA influences expression of both sarT and sarS in the …

An Interdisciplinary And Synthetic Approach To Ecological Boundaries, Mary L. Cadenasso, Steward T. A. Pickett, Kathleen C. Weathers, Susan S. Bell, Tracy L. Benning, Margaret M. Carreiro, Todd E. Dawson

Integrative Biology Faculty and Staff Publications

We introduce a collection of articles that proposes conceptual and methodological tools to advance the integrated study of ecological boundaries. A number of studies are germane to understanding the structure and function of boundaries over a wide array of ecological systems and scales. However, these studies have not been unified in a consistent theoretical framework. To integrate these seemingly disparate studies and to advance future research on boundaries, these articles present a common conceptual framework, a classification of the different types of boundaries and their potential functions, and statistical and modeling approaches that can be applied to a wide range …

The Virulence Activator Apha Links Quorum Sensing To Pathogenesis And Physiology In Vibrio Cholerae By Repressing The Expression Of A Penicillin Amidase Gene On The Small Chromosome, Gabriela Kovacikova, Wei Lin, Karen Skorupski

Dartmouth Scholarship

Activation of the tcpPH promoter on the Vibrio pathogenicity island by AphA and AphB initiates the Vibrio cholerae virulence cascade and is regulated by quorum sensing through the repressive action of HapR on aphA expression. To further understand how the chromosomally encoded AphA protein activates tcpPH expression, site-directed mutagenesis was used to identify the base pairs critical for AphA binding and transcriptional activation. This analysis revealed a region of partial dyad symmetry, TATGCA-N6-TNCNNA, that is important for both of these activities. Searching the V. cholerae genome for this binding site permitted the identification of a second one upstream of a …

Computational Models For Diffusion Of Second Messengers In Visual Transduction, Harihar Khanal

Publications

The process of phototransduction, whereby light is converted into an electrical response in retinal rod and cone photoreceptors, involves, as a crucial step, the diffusion of cytoplasmic signaling molecules, termed second messengers. A barrier to mathematical and computational modeling is the complex geometry of the rod outer segment which contains about 1000 thin discs. Most current investigations on the subject assume a well-stirred bulk aqueous environment thereby avoiding such geometrical complexity. We present theoretical and computational spatio-temporal models for phototransduction in vertebrate rod photoreceptors, which are pointwise in nature and thus take into account the complex geometry of the …

Genetic Polymorphisms Of The Interleukin-1 Gene And Early Marginal Bone Loss Around Endosseous Dental Implants, Hitomi Shimpuku, Yasuhiro Nosaka, Tatsuya Kawamura, Yoichi Tachi, Mitsuko Shinohara, Kiyoshi Ohura

Faculty, Staff and Student Publications

Dental implant surgery commonly proceeds in two stages. It is generally accepted that bone loss around implants does not occur at stage-II surgery because implants do not receive mechanical loading. However, early marginal bone loss around implants occasionally does occur during the healing period. Genetic polymorphisms in the interleukin-1 (IL-1) gene have been reported to be important for bone homeostasis and susceptibility to bone disease. We therefore investigated whether the idiopathic early marginal bone loss around implants is related to polymorphisms in the IL-1 gene. We performed a case-control study. Patients demonstrating marginal bone loss around implants at stage-II surgery …

Characterization Of Mutations And Loss Of Heterozygosity Of P53 And K-Ras2 In Pancreatic Cancer Cell Lines By Immobilized Polymerase Chain Reaction, James Butz, Eric Wickstrom, Jeremy Edwards

Department of Biochemistry and Molecular Biology Faculty Papers

Background

The identification of known mutations in a cell population is important for clinical applications and basic cancer research. In this work an immobilized form of the polymerase chain reaction, referred to as polony technology, was used to detect mutations as well as gene deletions, resulting in loss of heterozygosity (LOH), in cancer cell lines. Specifically, the mutational hotspots in p53, namely codons 175, 245, 248, 249, 273, and 282, and K-ras2, codons 12, 13 and 61, were genotyped in the pancreatic cell line, Panc-1. In addition LOH analysis was also performed for these same two genes in Panc-1 by …

Gaze-Centered Updating Of Visual Space In Human Parietal Cortex., W Pieter Medendorp, Herbert C Goltz, Tutis Vilis, J Douglas Crawford

Brain and Mind Institute Researchers' Publications

Single-unit recordings have identified a region in the posterior parietal cortex (PPC) of the monkey that represents and updates visual space in a gaze-centered frame. Here, using event-related functional magnetic resonance imaging, we identified an analogous bilateral region in the human PPC that shows contralateral topography for memory-guided eye movements and arm movements. Furthermore, when eye movements reversed the remembered horizontal target location relative to the gaze fixation point, this PPC region exchanged activity across the two cortical lobules. This shows that the human PPC dynamically updates the spatial goals for action in a gaze-centered frame.

Use Of In Vivo-Induced Antigen Technology (Iviat) To Identify Genes Uniquely Expressed During Human Infection With Vibrio Cholerae, Long Hang, Manohar John, Muhammad Asaduzzaman, Emily A. Bridges, Cecily Vanderspurt, Thomas J. Kirn, Ronald K. Taylor

Dartmouth Scholarship

In vivo-induced antigen technology is a method to identify proteins expressed by pathogenic bacteria during human infection. Sera from 10 patients convalescing from cholera infection in Bangladesh were pooled, adsorbed against in vitro-grown El Tor Vibrio cholerae O1, and used to probe a genomic expression library in Escherichia coli constructed from El Tor V. cholerae O1 strain N16961. We identified 38 positive clones in the screen, encoding pili (PilA and TcpA), cell membrane proteins (PilQ, MshO, MshP, and CapK), methyl-accepting chemotaxis proteins, chemotaxis and motility proteins (CheA and CheR), a quorum-sensing protein (LuxP), and four hypothetical proteins. Analysis of immune …

In Vitro Regeneration And Genetic Transformation Of Sesbania Drummondii: A Medicinally And Environmentally Important Plant, Satish Cheepala

Masters Theses & Specialist Projects

This study describes rapid propagation of Sesbania drummondii using nodal explants isolated from seedlings and young plants. The nodal segments proliferated into multiple shoots on Murashige and Skoog (MS) medium supplemented with 22.2 /M benzyladenine. Murashige and Skoog medium containing 2.2 and 4.5 //M thidiazuron induced 5 - 6 healthier shoots per axillary node from 3-month-old plants. Nodal segments cultured on MS medium containing combinations of benzyladenine (8.8 and 11.1 /JM) and either indole-3-butyric acid (0.24 - 2.46 //M) or indole-3-acetic acid (0.28 - 2.85 //M) produced fewer shoots. Callus when subcultured on 2.2 /LihA thidiazuron containing medium resulted in …

College Of Medical Science Student Handbook July 2003, Nova Southeastern University

Health Professions Divisions Course Catalogs and Course Descriptions

No abstract provided.

The Lateral Occipital Complex Subserves The Perceptual Persistence Of Motion-Defined Groupings., Susanne Ferber, G Keith Humphrey, Tutis Vilis

Brain and Mind Institute Researchers' Publications

How are the bits and pieces of retinal information assembled and integrated to form the coherent objects that we see? One long-established principle is that elements that move as a group are linked together. For instance a fragmented line-drawing of an object, placed on a background of randomly distributed short lines, can be impossible to see. But if the object moves relative to the background, its shape is instantly recognized. Even after the motion stops, the percept of the object persists briefly before it fades into the background of random lines. Where in the brain does the percept of the …

Efecto De La Gnrh En El Proceso Del Reconocimiento Maternal De La Preñez Sobre La Supervivencia Embrionaria En Alpacas., Mariluz Araínga, Victor Leyva V., Wilber Garcia V., Enrique Franco Li.

Journal Articles: Pharmacology & Experimental Neuroscience

The effect of GnRH administered around the time of maternal recognition of prenancy on the embryonic survival rate was studied. This study used 67 adult female alpacas sexually receptive to the male, and bearing a preovulatory follicle ≥ 7mm, detected by rectal ultrasonography. Animals were distributed in three groups: Go (n=23) as control; G1 (n=22) received 6 µg GnRH on day 4 after ovulation; and G2 (n=22) received 4 µg GnRH on days 8 and 9 after ovulation. The ocurrence of ovulation was confirmed through the detection of a corpus luteum (CL) on day 5 after ovulation. Fertilization and gestation …

Crystal Structure Of The Sars Protein From Staphylococcus Aureus, Ronggui Li, Adhar C. Manna, Shaodong Dai, Ambrose L. Cheung, Gongyi Zhang

Dartmouth Scholarship

The expression of virulence determinants in Staphylococcus aureus is controlled by global regulatory loci (e.g., sarA and agr). One of these determinants, protein A (spa), is activated by sarS, which encodes a 250-residue DNA-binding protein. Genetic analysis indicated that the agr locus likely mediates spa repression by suppressing the transcription of sarS. Contrary to SarA and SarR, which require homodimer formation for proper function, SarS is unusual within the SarA protein family in that it contains two homologous halves, with each half sharing sequence similarity to SarA and SarR. Here we report the 2.2 Å …

Alginate Is Not A Significant Component Of The Extracellular Polysaccharide Matrix Of Pa14 And Pao1 Pseudomonas Aeruginosa Biofilms, Daniel J. Wozniak, Timna J. O. Wyckoff, Melissa Starkey, Rebecca Keyser, Parastoo Azadi, George A. O'Toole, Matthew R. Parsek

Dartmouth Scholarship

The bacterium Pseudomonas aeruginosa causes chronic respiratory infections in cystic fibrosis (CF) patients. Such infections are extremely difficult to control because the bacteria exhibit a biofilm-mode of growth, rendering P. aeruginosa resistant to antibiotics and phagocytic cells. During the course of infection, P. aeruginosa usually undergoes a phenotypic switch to a mucoid colony, which is characterized by the overproduction of the exopolysaccharide alginate. Alginate overproduction has been implicated in protecting P. aeruginosa from the harsh environment present in the CF lung, as well as facilitating its persistence as a biofilm by providing an extracellular matrix that promotes adherence. Because of …

A Functional Relationship Between Numa And Kid Is Involved In Both Spindle Organization And Chromosome Alignment In Vertebrate Cells, Aime A. Levesque, Louisa Howard, Michael B. Gordon, Duane A. Compton

Dartmouth Scholarship

We examined spindle morphology and chromosome alignment in vertebrate cells after simultaneous perturbation of the chromokinesin Kid and either NuMA, CENP-E, or HSET. Spindle morphology and chromosome alignment after simultaneous perturbation of Kid and either HSET or CENP-E were no different from when either HSET or CENP-E was perturbed alone. However, short bipolar spindles with organized poles formed after perturbation of both Kid and NuMA in stark contrast to splayed spindle poles observed after perturbation of NuMA alone. Spindles were disorganized if Kid, NuMA, and HSET were perturbed, indicating that HSET is sufficient for spindle organization in the absence of …

Probucol Prevents Early Coronary Heart Disease And Death In The High-Density Lipoprotein Receptor Sr-Bi/Apolipoprotein E Double Knockout Mouse, Anne Braun, Songwen Zhang, Helena E. Miettinen, Shamsah Ebrahim, Teresa M. Holm, Eliza Vasile, Mark J. Post

Dartmouth Scholarship

Mice with homozygous null mutations in the high-density lipoprotein receptor SR-BI (scavenger receptor class B, type I) and apolipoprotein E genes fed a low-fat diet exhibit a constellation of pathologies shared with human atherosclerotic coronary heart disease (CHD): hypercholesterolemia, occlusive coronary atherosclerosis, myocardial infarctions, cardiac dysfunction (heart enlargement, reduced systolic function and ejection fraction, and ECG abnormalities), and premature death (mean age 6 weeks). They also exhibit a block in RBC maturation and abnormally high plasma unesterified-to-total cholesterol ratio (0.8) with associated abnormal lipoprotein morphology (lamellar/vesicular and stacked discoidal particles reminiscent of those in lecithin/cholesterol acyltransferase deficiency and cholestasis). Treatment …

Neuronal Cell Model And Methods Of Use Thereof, Craig S. Miller, Robert J. Jacob, Robert J. Danaher

Microbiology, Immunology and Molecular Genetics Faculty Patents

We previously described a novel in vitro model of a non-productive herpes simplex virus type 1 (HSV-1) infection in neurally-differentiated (ND)-PC12 cells that allows for inducible virus replication upon forskolin and heat stress (HS) treatment. In this research, we further characterized the model with respect to HSV-2 strain 333. We found that: (i) ND-PC12 cells are non-permissive to HSV-2 replication; (ii) HSV-2 can establish a quiescent infection, like HSV-1, in ND-PC12 cells with the transient use of acycloguanosine (ACV); however unlike HSV-1, anti-viral conditions are not obligatory to establish and maintain a quiescent state; (iii) the quiescent state is maintained …

Actinomyces Pyogenes Causante De Aborto En Bovinos, Mariluz Araínga, Nieves Sandoval Ch., Erik R. Zacharias, Hermelinda Rivera G.

Journal Articles: Pharmacology & Experimental Neuroscience

A case of fetal bovine abortion due to Actinomyces pyogenes in a dairy herd of Cieneguilla valley of Lima, Peru is reported. A bovine fetus of four months of gestation was aborted and submitted for laboratory examination. Macroscopic lesions in fetal tissues were not found with the exception of numerous white foci up to 1mm in diameter in the lungs. Various fetal tissue samples were collected for virologic, bacteriologic and histopathologic examinations. Bovine viral diarrhea virus (BVDV) and Neospora caninum antigen were ruled out by immunohistochemistry but, pure colonies of A. pyogenes were isolated from the lung and other fetal …

Interaction Between Adrenergic And Nitric Oxide-Releasing Nerves In Cerebral Arteries, Emmanuel Ngu Mbaku

Loma Linda University Electronic Theses, Dissertations & Projects

Of all body tissues, the brain is the least tolerant of ischemia so much that interruption of cerebral blood flow by 5 sec can cause syncope, with irreversible tissue damage if the ischemia last a few minutes. In this respect, the body has an imperative duty of ensuring constant and adequate blood supply to the brain. It does so through a series of intrinsic and extrinsic control factors of which adrenergic and nitric oxide-releasing nerves are components. My research examined the interaction between these two nerve-types with emphasis on the mechanisms involved as well as on changes in their functions …

Residency Program At Michael E Debakey Department Of Surgery, Baylor College Of Medicine, F Charles Brunicardi

Faculty, Staff and Students Publications

No abstract provided.