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Community Based Epidemiological Study Of Chagas Disease In Rural Peru, Paul Walker

Yale Medicine Thesis Digital Library

The purpose of this study was to evaluate the epidemiology of Trypanosoma cruzi infection, to valuate the TESA blot, and to characterize cardiac findings of patients with Chagas disease in a rural setting near Arequipa, Peru. The study site was the town of Quequeña, Peru with a population of 774 with 236 inhabitants under the age of 18 according to the 2005 census conducted by Peru. A fumigation/insect collection campaign was done in December of 2006 to quantify household infestation levels, document housing characteristics, and GPS household locations. Of the 602 people surveyed to be living in Quequeña, blood samples …

Listening To Student Voices: Web-Based Mentoring For Black Male Students With Emotional Disorders, David Grant

Electronic Theses and Dissertations

The voices of Black male students labeled ED are seldom heard regarding their perspectives on education and their lives in general. By excluding their opinions, educators are missing an important aspect that could improve educational services for Black males with ED. Therefore, this study was undertaken to determine the implications of Web-based mentoring as a platform for Black male students with ED to articulate their thoughts on the factors that impact their behaviors and achievement. Mentoring as an intervention granted Black males with ED a platform to share their thoughts. Technology was used as an educational resource to academically engage …

Dominance Of The Proximal Coordinate Frame In Determining The Locations Of Hippocampal Place Cell Activity During Navigation

Faculty, Staff and Student Publications

The place-specific activity of hippocampal cells provides downstream structures with information regarding an animal's position within an environment and, perhaps, the location of goals within that environment. In rodents, recent research has suggested that distal cues primarily set the orientation of the spatial representation, whereas the boundaries of the behavioral apparatus determine the locations of place activity. The current study was designed to address possible biases in some previous research that may have minimized the likelihood of observing place activity bound to distal cues. Hippocampal single-unit activity was recorded from six freely moving rats as they were trained to perform …

Eomesodermin, A Target Gene Of Pou4f2, Is Required For Retinal Ganglion Cell And Optic Nerve Development In The Mouse, Chai-An Mao, Takae Kiyama, Ping Pan, Yasuhide Furuta, Anna-Katerina Hadjantonakis

Faculty, Staff and Student Publications

The mechanisms regulating retinal ganglion cell (RGC) development are crucial for retinogenesis and for the establishment of normal vision. However, these mechanisms are only vaguely understood. RGCs are the first neuronal lineage to segregate from pluripotent progenitors in the developing retina. As output neurons, RGCs display developmental features very distinct from those of the other retinal cell types. To better understand RGC development, we have previously constructed a gene regulatory network featuring a hierarchical cascade of transcription factors that ultimately controls the expression of downstream effector genes. This has revealed the existence of a Pou domain transcription factor, Pou4f2, that …

Correlates Of Tobacco Cessation Counseling Among Hispanic Physicians In The Us: A Cross-Sectional Survey Study

Faculty, Staff and Student Publications

BACKGROUND: Physician advice is an important motivator for attempting to stop smoking. However, physicians' lack of intervention with smokers has only modestly improved in the last decade. Although the literature includes extensive research in the area of the smoking intervention practices of clinicians, few studies have focused on Hispanic physicians. The purpose of this study was to explore the correlates of tobacco cessation counseling practices among Hispanic physicians in the US. METHODS: Data were collected through a validated survey instrument among a cross-sectional sample of self-reported Hispanic physicians practicing in New Mexico, and who were members of the New Mexico …

Genes In Glucose Metabolism And Association With Spina Bifida, Irene Townsend

Faculty, Staff and Student Publications

The authors test single nucleotide polymorphisms (SNPs) in coding sequences of 12 candidate genes involved in glucose metabolism and obesity for associations with spina bifida. Genotyping was performed on 507 children with spina bifida and their parents plus anonymous control DNAs from Hispanic and Caucasian individuals. The transmission disequilibrium test was performed to test for genetic associations between transmission of alleles and spina bifida in the offspring (P < .05). A statistically significant association between Lys481 of HK1 (G allele), Arg109Lys of LEPR (G allele), and Pro196 of GLUT1 (A allele) was found ( P = .019, .039, and .040, respectively). Three SNPs on 3 genes involved with glucose metabolism and obesity may be associated with increased susceptibility to spina bifida.

Searching For The Majority: Algorithms Of Voluntary Control

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 …

Short-Wavelength Light Sensitivity Of Circadian, Pupillary, And Visual Awareness In Humans Lacking An Outer Retina, Farhan H. Zaidi, Joseph T. Hull, Stuart N. Peirson, Katharina Wulff, Daniel Aeschbach, Joshua J. Gooley, George C. Brainard, Kevin Gregory-Evans, Joseph F. Rizzo Iii, Charles A. Czeisler, Russell G. Foster, Merrick J. Moseley, Steven W. Lockley

Department of Neurology Faculty Papers

As the ear has dual functions for audition and balance, the eye has a dual role in detecting light for a wide range of behavioral and physiological functions separate from sight. These responses are driven primarily by stimulation of photosensitive retinal ganglion cells (pRGCs) that are most sensitive to short-wavelength ( approximately 480 nm) blue light and remain functional in the absence of rods and cones. We examined the spectral sensitivity of non-image-forming responses in two profoundly blind subjects lacking functional rods and cones (one male, 56 yr old; one female, 87 yr old). In the male subject, we found …

Illusory Predictors: Generalizability Of Findings In Cocaine Treatment Retention Research, Joy M Schmitz

Faculty, Staff and Student Publications

Treatment retention is of paramount importance in cocaine treatment research as treatment completion rates are often 50% or less. Failure to retain cocaine patients in treatment has both significant research and clinical implications. In this paper we qualitatively and quantitatively demonstrate the inconsistency found across analyses of retention predictors in order to highlight the problem. First, a qualitative review of the published literature was undertaken to identify the frequency of predictors studied and their relations to treatment retention. Second, an empirical demonstration of predictor stability was conducted by testing a common set of variables across three similar 12-week cocaine clinical …

The Activity Of Azithromycin Against Leishmania (Viannia) Braziliensis And Leishmania (Leishmania) Amazonensis In The Golden Hamster Model., Angel Sinagra, Concepción Luna, David Abraham, Maria Del Carmen Iannella, Adelina Riarte, Alejandro J. Krolewiecki

Department of Microbiology and Immunology Faculty Papers

New therapeutic alternatives against leishmaniasis remain a priority. The activity of azithromycin against Leishmania (Leishmania) major has been previously demonstrated. Different responses among species of Leishmania make species-specific drug screening necessary. The activity of azithromycin against Leishmania (Viannia) braziliensis and Leishmania (Leishmania) amazonensis was evaluated in golden hamsters infected through footpad injections of metacyclic promastigotes, and compared with untreated controls and animals treated with meglumine antimoniate. Footpad thickness, lesion cultures and dissemination sites were analyzed. Treatment of golden hamsters with oral azithromycin at 450mg/kg had no activity against infections with Leishmania (Leishmania) amazonensis. For infections due to Leishmania (Viannia) braziliensis, …

The Resurgence Of The Adora2b Receptor As An Immunotherapeutic Target In Pancreatic Cancer

Faculty, Staff and Student Publications

Subfields of the hippocampus display differential dynamics in processing a spatial environment, especially when changes are introduced to the environment. Specifically, when familiar cues in the environment are spatially rearranged, place cells in the CA3 subfield tend to rotate with a particular set of cues (e.g., proximal cues), maintaining a coherent spatial representation. Place cells in CA1, in contrast, display discordant behaviors (e.g., rotating with different sets of cues or remapping) in the same condition. In addition, on average, CA3 place cells shift their firing locations (measured by the center of mass, or COM) backward over time when the animal …

Is A 3-Mm Intrafractional Margin Sufficient For Daily Image-Guided Intensity-Modulated Radiation Therapy Of Prostate Cancer?, Adam D Melancon, Jennifer C O'Daniel, Lifei Zhang, Rajat J Kudchadker, Deborah A Kuban, Rex M Cheung, Susan L Tucker, Wayne D Newhauser, Radhe Mohan, Lei Dong

Faculty, Staff and Student Publications

PURPOSE: To determine whether a 3-mm isotropic target margin adequately covers the prostate and seminal vesicles (SVs) during administration of an intensity-modulated radiation therapy (IMRT) treatment fraction, assuming that daily image-guided setup is performed just before each fraction.

MATERIALS AND METHODS: In-room computed tomographic (CT) scans were acquired immediately before and after a daily treatment fraction in 46 patients with prostate cancer. An eight-field IMRT plan was designed using the pre-fraction CT with a 3-mm margin and subsequently recalculated on the post-fraction CT. For convenience of comparison, dose plans were scaled to full course of treatment (75.6 Gy). Dose coverage …

Rhabdomyolysis After Laparoscopic Nephrectomy., Deborah T. Glassman, William G. Merriam, Edouard J. Trabulsi, Dolores Byrne, Leonard Gomella

Department of Urology Faculty Papers

BACKGROUND AND OBJECTIVES: Laparoscopic renal surgery has become a widely applied technique in recent years. The development of postoperative rhabdomyolysis is a known but rare complication of laparoscopic renal surgery. Herein, 4 cases of rhabdomyolysis and a review of the literature are presented with respect to pathogenesis, treatment, and prevention of this dire complication. METHODS: A retrospective review of over 600 laparoscopic renal operations over the past 8 years was performed. All cases of postoperative rhabdomyolysis were identified. A Medline search was performed to find articles related to the development of postoperative rhabdomyolysis. Cases of rhabdomyolysis developing after laparoscopic renal …

Western Diet, But Not High Fat Diet, Causes Derangements Of Fatty Acid Metabolism And Contractile Dysfunction In The Heart Of Wistar Rats, Heinrich Taegtmeyer

Faculty, Staff and Student Publications

Obesity and diabetes are associated with increased fatty acid availability in excess of muscle fatty acid oxidation capacity. This mismatch is implicated in the pathogenesis of cardiac contractile dysfunction and also in the development of skeletal-muscle insulin resistance. We tested the hypothesis that 'Western' and high fat diets differentially cause maladaptation of cardiac- and skeletal-muscle fatty acid oxidation, resulting in cardiac contractile dysfunction. Wistar rats were fed on low fat, 'Western' or high fat (10, 45 or 60% calories from fat respectively) diet for acute (1 day to 1 week), short (4-8 weeks), intermediate (16-24 weeks) or long (32-48 weeks) …

Polymorphisms In Nucleotide Excision Repair Genes, Arsenic Exposure, And Non-Melanoma Skin Cancer In New Hampshire, Katie M. Applebaum, Margaret R. Karagas, David J. Hunter, Paul J. Catalano, Steven H. Byler, Steve Morris, Heather H. Nelson

Dartmouth Scholarship

Background:

Arsenic exposure may alter the efficiency of DNA repair. UV damage is specifically repaired by nucleotide excision repair (NER), and common genetic variants in NER may increase risk for non-melanoma skin cancer (NMSC).

Objective:

We tested whether polymorphisms in the NER genes XPA (A23G) and XPD (Asp312Asn and Lys751Gln) modify the association between arsenic and NMSC.

Methods:

Incident cases of basal and squamous cell carcinoma (BCC and SCC, respectively) were identified through a network of dermatologists and pathology laboratories across New Hampshire. Population-based controls were frequency matched to cases on age and sex. Arsenic exposure was assessed in toenail …

Relationships Between Scores On The Jefferson Scale Of Physician Empathy, Patient Perceptions Of Physician Empathy, And Humanistic Approaches To Patient Care: A Validity Study., Karen M. Glaser, Fred W. Markham, Herbert M. Adler, Patrick R. Mcmanus, Mohammadreza Hojat

Department of Psychiatry and Human Behavior Faculty Papers

BACKGROUND: Empathy is the backbone of a positive physician-patient relationship. Physician empathy and the patient's awareness of the physician's empathic concern can lead to a more positive clinical outcome.

MATERIAL/METHODS: The Jefferson Scale of Physician Empathy (JSPE) was completed by 36 physicians in the Family Medicine residency program at Thomas Jefferson University Hospital, and 90 patients evaluated these physicians by completing the Jefferson Scale of Patient Perceptions of Physician Empathy (JSPPPE), and a survey about physicians' humanistic approaches to patient care.

RESULTS: A statistically significant correlation was found between scores of the JSPE and JSPPPE (r=0.48, p

CONCLUSIONS: These findings …

Epstein-Barr Virus Infection Of Langerhans Cell Precursors As A Mechanism Of Oral Epithelial Entry, Persistence, And Reactivation

Faculty, Staff and Student Publications

Epstein-Barr virus (EBV) is a ubiquitous human herpesvirus associated with many malignant and nonmalignant human diseases. Life-long latent EBV persistence occurs in blood-borne B lymphocytes, while EBV intermittently productively replicates in mucosal epithelia. Although several models have previously been proposed, the mechanism of EBV transition between these two reservoirs of infection has not been determined. In this study, we present the first evidence demonstrating that EBV latently infects a unique subset of blood-borne mononuclear cells that are direct precursors to Langerhans cells and that EBV both latently and productively infects oral epithelium-resident cells that are likely Langerhans cells. These data …

Neural Reprogramming In Retinal Degeneration, David W Marshak

Faculty, Staff and Student Publications

PURPOSE: Early visual defects in degenerative diseases such as retinitis pigmentosa (RP) may arise from phased remodeling of the neural retina. The authors sought to explore the functional expression of ionotropic (iGluR) and group 3, type 6 metabotropic (mGluR6) glutamate receptors in late-stage photoreceptor degeneration.

METHODS: Excitation mapping with organic cations and computational molecular phenotyping were used to determine whether retinal neurons displayed functional glutamate receptor signaling in rodent models of retinal degeneration and a sample of human RP.

RESULTS: After photoreceptor loss in rodent models of RP, bipolar cells lose mGluR6 and iGluR glutamate-activated currents, whereas amacrine and ganglion …

Quantitative Diffusion Tensor Imaging Detects Dopaminergic Neuronal Degeneration In A Murine Model Of Parkinson's Disease, Erin Mcintyre, R Lee Mosley

Faculty, Staff and Student Publications

Early diagnosis of Parkinson's disease (PD) is required to improve therapeutic responses. Indeed, a clinical diagnosis of resting tremor, rigidity, movement and postural deficiencies usually reflect >50% loss of the nigrostriatal system in disease. In a step to address this, quantitative diffusion tensor magnetic resonance imaging (DTI) was used to assess nigrostriatal degeneration in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) intoxication model of dopaminergic nigral degeneration. We now demonstrate increased average diffusion (p

Chronic Administration Of Methylphenidate Produces Neurophysiological And Behavioral Sensitization

Faculty, Staff and Student Publications

The electrophysiological properties of acute and chronic methylphenidate (MPD) on neurons of the prefrontal cortex (PFC) and caudate nucleus (CN) have not been studied in awake, freely behaving animals. The present study was designed to investigate the dose-response effects of MPD on sensory evoked potentials recorded from the PFC and CN in freely behaving rats previously implanted with permanent electrodes, as well as their behavioral (locomotor) activities. On experimental day 1, locomotor behavior of rats was recorded for 2 h post-saline injection, and sensory evoked field potentials were recorded before and after saline and 0.6, 2.5, and 10 mg/kg, i.p., …

Health Barriers, Health Perceptions, And Cardiovascular Risk Factors Of Adolescent Black American Males, Desmarie Jackson Decuir

Theses and Dissertations (ETD)

Area of Investigation: Cardiovascular (CV) diseases are the leading cause of death among Black American adult males. Health behaviors that contribute to CV disease are probably learned during adolescence yet few researchers have studied the factors that influence health promotion behaviors in adolescent Black American males. This study described the health barriers, health perceptions (health self-efficacy and health status), and CV risk factors reported by and the influence of these variables on health promotion behaviors of a sample of Black American adolescent males without known CV disease.

Methods and Procedures: A descriptive correlation study design was used to …

Functional Dissociation In Frontal And Striatal Areas For Processing Of Positive And Negative Reward Information, Xun Liu, David K. Powell, Hongbin Wang, Brian T. Gold, Christine R. Corbly, Jane E. Joseph

Neuroscience Faculty Publications

Reward-seeking behavior depends critically on processing of positive and negative information at various stages such as reward anticipation, outcome monitoring, and choice evaluation. Behavioral and neuropsychological evidence suggests that processing of positive (e.g., gain) and negative (e.g., loss) reward information may be dissociable and individually disrupted. However, it remains uncertain whether different stages of reward processing share certain neural circuitry in frontal and striatal areas, and whether distinct but interactive systems in these areas are recruited for positive and negative reward processing. To explore these issues, we used a monetary decision-making task to investigate the roles of frontal and striatal …

Signaling Through Galphai2 Protein Is Required For Recruitment Of Neutrophils For Antibody-Mediated Elimination Of Larval Strongyloides Stercoralis In Mice., Udaikumar M. Padigel, Louis Stein, Kevin Redding, James J. Lee, Thomas J. Nolan, Gerhard A. Schad, Lutz Birnbaumer, David Abraham

Department of Microbiology and Immunology Faculty Papers

The heterotrimeric guanine nucleotide-binding protein Galphai2 is involved in regulation of immune responses against microbial and nonmicrobial stimuli. Galphai2-/- mice have a selectively impaired IgM response consistent with a disorder in B cell development yet have augmented T cell effector function associated with increased production of IFN-gamma and IL-4. The goal of the present study was to determine if a deficiency in the Galphai2 protein in mice would affect the protective immune response against Strongyloides stercoralis, which is IL-4-, IL-5-, and IgM-dependent. Galphai2-/- and wild-type mice were immunized and challenged with S. stercoralis larvae and analyzed for protective immune responses …

Ambulatory Care Adverse Events And Preventable Adverse Events Leading To A Hospital Admission, Troyen A Brennan

Faculty, Staff and Student Publications

BACKGROUND: Most healthcare in the US is delivered in the ambulatory care setting, but the epidemiology of errors and adverse events in ambulatory care is understudied.

METHODS: Using the population-based data from the Colorado and Utah Medical Practices Study, we identified adverse events that occurred in an ambulatory care setting and led to hospital admission. Proportions with 95% CIs are reported.

RESULTS: We reviewed 14,700-hospital discharge records and found 587 adverse events of which 70 were ambulatory care adverse events (AAEs) and 31 were ambulatory care preventable adverse events (APAEs). When weighted to the general population, there were 2608 AAEs …

Sociodemographic Characteristics And Diabetes Predict Invalid Self-Reported Non-Smoking In A Population-Based Study Of U.S. Adults, Monica A. Fisher, George W. Taylor, Brent J. Shelton, Sara M. Debanne

Markey Cancer Center Faculty Publications

BACKGROUND: Nearly all studies reporting smoking status collect self-reported data. The objective of this study was to assess sociodemographic characteristics and selected, common smoking-related diseases as predictors of invalid reporting of non-smoking. Valid self-reported smoking may be related to the degree to which smoking is a behavior that is not tolerated by the smoker's social group.

METHODS: True smoking was defined as having serum cotinine of 15+ng/ml. 1483 "true" smokers 45+ years of age with self-reported smoking and serum cotinine data from the Mobile Examination Center were identified in the third National Health and Nutrition Examination Survey. Invalid non-smoking was …

Transgenic Avian-Derived Recombinant Human Interferon-Alpha2b (Avi-005) In Healthy Subjects: An Open-Label, Single-Dose, Controlled Study., T B Patel, E Pequignot, S H Parker, M C Leavitt, H E Greenberg, Walter K. Kraft

Department of Pharmacology and Experimental Therapeutics Faculty Papers

BACKGROUND/AIMS: This study characterized the safety and pharmacological properties of AVI-005, a novel glycosylated recombinant human interferon-alpha2b produced from the egg whites of chickens transfected with human cDNA.

METHODS: 18 healthy volunteers received single subcutaneous rising doses (0.5, 1.66 or 5 million international units, MIU) of AVI-005. A randomized parallel comparator group of 10 subjects received 5 MIU of unglycosylated IFN-alpha2b (Intron A). The pharmacokinetic parameters t1/2, tmax, Cmax, AUC0-24h, Vd, and clearance were compared between AVI-005 and unglycosylated IFN-alpa2b.

RESULTS: At equipotent doses, AVI-005 had a larger AUC0-24h than the control interferon. Pharmacodynamic markers ofneopterin and beta2-microglobulin for the …

Severe Aortic And Arterial Aneurysms Associated With A Tgfbr2 Mutation, Joseph S Coselli

Faculty, Staff and Student Publications

BACKGROUND: A 24-year-old man presented with previously diagnosed Marfan's syndrome. Since the age of 9 years, he had undergone eight cardiovascular procedures to treat rapidly progressive aneurysms, dissection and tortuous vascular disease involving the aortic root and arch, the thoracoabdominal aorta, and brachiocephalic, vertebral, internal thoracic and superior mesenteric arteries. Throughout this extensive series of cardiovascular surgical repairs, he recovered without stroke, paraplegia or renal impairment.

INVESTIGATIONS: CT scans, arteriogram, genetic mutation screening of transforming growth factor beta receptors 1 and 2.

DIAGNOSIS: Diffuse and rapidly progressing vascular disease in a patient who met the diagnostic criteria for Marfan's syndrome, …

Imaging Of Pulmonary Embolism And T-Pa Therapy Effects Using Mdct And Liposomal Iohexol Blood Pool Agent: Preliminary Results In A Rabbit Model, Ketan B Ghaghada, Jered Sieren, Edwin J R Van Beek

Faculty, Staff and Student Publications

RATIONALE AND OBJECTIVES: Polyethylene glycol-coated liposomal blood pool contrast agents maintain contrast enhancement over several hours. This study aimed to evaluate (long-term) imaging of pulmonary arteries, comparing conventional iodinated contrast with a liposomal blood pool contrast agent. Also, visualization of the (real-time) therapeutic effects of tissue plasminogen activator (t-PA) on pulmonary embolism (PE) was attempted. MATERIALS AND METHODS: Six rabbits (weight approximately 4 kg) had autologous blood clots injected through the superior vena cava. Imaging was performed using conventional contrast (iohexol, 350 mg I/ml; GE HealthCare, Princeton, NJ) at a dose of 1400 mg I per animal, and after wash-out, …

Hepatitis C Risk Assessment, Testing And Referral For Treatment In Urban Primary Care: Role Of Race And Ethnicity., Stacey B. Trooskin, Victor J. Navarro, Robert J. Winn, David J. Axelrod, A. Scott Mcneal, Maricruz Velez, Steven K. Herrine, Simona Rossi

Division of Gastroenterology and Hepatology Faculty Papers

AIM: To determine rates of hepatitis C (HCV) risk factor ascertainment, testing, and referral in urban primary care practices, with particular attention to the effect of race and ethnicity.

METHODS: Retrospective chart review from four primary care sites in Philadelphia; two academic primary care practices and two community clinics was performed. Demographics, HCV risk factors, and other risk exposure information were collected.

RESULTS: Four thousand four hundred and seven charts were reviewed. Providers documented histories of injection drug use (IDU) and transfusion for less than 20% and 5% of patients, respectively. Only 55% of patients who admitted IDU were tested …

Traumatic Brain Injury Stimulates Hippocampal Catechol-O-Methyl Transferase Expression In Microglia

Faculty, Staff and Student Publications

Outcome following traumatic brain injury (TBI) is in large part determined by the combined action of multiple processes. In order to better understand the response of the central nervous system to injury, we utilized an antibody array to simultaneously screen 507 proteins for altered expression in the injured hippocampus, a structure critical for memory formation. Array analysis indicated 41 candidate proteins have altered expression levels 24h after TBI. Of particular interest was catechol-O-methyl transferase (COMT), an enzyme involved in metabolizing catecholamines released following neuronal activity. Altered catecholamine signaling has been observed after brain injury, and may contribute to the cognitive …