Medical Specialties Commons^™

Airway Obstruction In Congenital Central Hypoventilation Syndrome, Alexandra K Reverdin, Ricardo Mosquera, Giuseppe N Colasurdo, Cindy K Jon, Roya M Clements

Faculty, Staff and Student Publications

Congenital central hypoventilation syndrome (CCHS) is the failure of the autonomic system to control adequate ventilation while asleep with preserved ventilatory response while awake. We report a case of a patient with CCHS who presented with intrathoracic and extrathoracic airway obstruction after tracheostomy tube decannulation and phrenic nerve pacer placement. Nocturnal polysomnography (NPSG) revealed hypoxia, hypercapnia and obstructive sleep apnoea, which required bilevel positive airway pressure titration. Airway endoscopy demonstrated tracheomalacia and paretic true vocal cords in the paramedian position during diaphragmatic pacing. Laryngeal electromyography demonstrated muscular electrical impulses that correlated with diaphragmatic pacer settings. Thus, we surmise that the …

Early Diagnosis And Treatment Of Invasive Pulmonary Aspergillosis In A Patient With Cystic Fibrosis, Ricardo Alberto Mosquera, Lila Estrada, Roya Mohebpour Clements, Cindy K Jon

Faculty, Staff and Student Publications

Invasive pulmonary aspergillosis is a rare and fatal complication in patients with cystic fibrosis (CF) who lack concomitant risk factors. The few documented cases in children have all resulted in deaths during hospitalisation. We present the case of a 12-year-old boy with CF who was admitted for an exacerbation which was unresponsive to antibiotic therapy. The findings on imaging raised concerns about a possible fungal infection. As a result, voriconazole therapy was started prior to his respiratory deterioration. He was later found to be β-D glucan and Aspergillus Ag galactomannan positive confirming the suspicion for invasive pulmonary aspergillosis. Three months …

Cholera Vaccination Campaign Contributes To Improved Knowledge Regarding Cholera And Improved Practice Relevant To Waterborne Disease In Rural Haiti, Omowunmi Aibana, Molly F Franke, Jessica E Teng, Johanne Hilaire, Max Raymond, Louise C Ivers

Faculty, Staff and Student Publications

BACKGROUND: Haiti's cholera epidemic has been devastating partly due to underlying weak infrastructure and limited clean water and sanitation. A comprehensive approach to cholera control is crucial, yet some have argued that oral cholera vaccination (OCV) might result in reduced hygiene practice among recipients. We evaluated the impact of an OCV campaign on knowledge and health practice in rural Haiti.

METHODOLOGY/PRINCIPAL FINDINGS: We administered baseline surveys on knowledge and practice relevant to cholera and waterborne disease to every 10th household during a census in rural Haiti in February 2012 (N = 811). An OCV campaign occurred from May-June 2012 after …

Website Usage And Weight Loss In A Free Commercial Online Weight Loss Program: Retrospective Cohort Study, Kevin O Hwang, Jing Ning, Amber W Trickey, Christopher N Sciamanna

Faculty, Staff and Student Publications

BACKGROUND: Online weight loss programs are increasingly popular. However, little is known about outcomes and associations with website usage among members of free online weight loss programs.

OBJECTIVE: This retrospective cohort study examined the association between website usage and weight loss among members of a free commercial online weight loss program (SparkPeople).

METHODS: We conducted a retrospective analysis of a systematic random sample of members who joined the program during February 1 to April 30, 2008, and included follow-up data through May 10, 2010. The main outcome was net weight change based on self-reported weight. Measures of website usage included …

Biomarkers Of Maternal And Fetal Exposure To Organochlorine Pesticides Measured In Pregnant Hispanic Women From Brownsville, Texas, Ken Sexton, Jennifer J Salinas, Thomas J Mcdonald, Rose M Z Gowen, Rebecca P Miller, Joseph B Mccormick, Susan P Fisher-Hoch

Faculty, Staff and Student Publications

Biomarkers of organochlorine pesticides were measured in both venous and umbilical cord blood from 35 pregnant Hispanic women living in Brownsville, Texas, USA. Gas chromatography with an electron capture detector was used to analyze specimens for 30 individual pesticides or their metabolites. Results indicate that blood concentrations were relatively low for most individual compounds, but that high-end (upper 10th percentile) values for total DDT were comparatively high. Although health effects associated with measured blood concentrations are uncertain, there is concern that fetal exposure to low levels of these OC compounds, either individually or in combination, might contribute to subsequent health …

Willingness To Undergo A Repeat Liver Biopsy Among Hiv/Hepatitis C Virus-Coinfected And Hepatitis C Virus-Monoinfected Patients, Valerianna K Amorosa, Omowunmi Aibana, Norah J Shire, Zachariah Dorey-Stein, Thomas Ferrara, Joanne Gilmore, Jay R Kostman, Vincent Lo Re

Faculty, Staff and Student Publications

BACKGROUND: Guidelines for chronic hepatitis C virus (HCV) management have recommended that a liver biopsy be repeated at 3-year intervals for HIV/HCV-coinfected patients and 5-year intervals for those with HCV monoinfection to assess fibrosis progression. However, it is unclear if patients are willing to repeat this procedure.

OBJECTIVE: To determine the prevalence and factors, particularly HIV coinfection, associated with willingness to repeat a liver biopsy.

METHODS: A questionnaire was administered to 235 HCV-infected patients (113 with HIV coinfection) between January 2008 and June 2011 who previously underwent liver biopsy. The main outcome was self-reported willingness to repeat the biopsy. The …

Acceptability Of Narratives To Promote Colorectal Cancer Screening In An Online Community, Kevin O Hwang, Amber W Trickey, Amanda L Graham, Eric J Thomas, Richard L Street, Jennifer L Kraschnewski, Sally W Vernon

Faculty, Staff and Student Publications

OBJECTIVE: To assess the acceptability of narratives to promote colorectal cancer (CRC) screening among members of an online weight loss community.

METHOD: Members of online weight loss community completed an Internet survey in 2010. Multiple logistic regression models examined demographic and attitudinal correlates of interest in sharing and receiving CRC screening narratives.

RESULTS: Participants (n=2386) were 92% female with mean (SD) age 58 (6) years; 68% were up-to-date with CRC screening. Among those who were up-to-date, 39% were interested in sharing their narratives with other members. African-Americans were more likely than other racial groups to be interested in sharing narratives …

Primary Care Providers’ Perspectives On Online Weight-Loss Programs: A Big Wish List, Kevin O Hwang, Heather L Stuckey, Monica C Chen, Jennifer L Kraschnewski, Samuel N Forjuoh, Jennifer M Poger, Kathleen M Mctigue, Christopher N Sciamanna

Faculty, Staff and Student Publications

BACKGROUND: Integrating online weight-loss programs into the primary care setting could yield substantial public health benefit. Little is known about primary care providers' perspectives on online weight-loss programs.

OBJECTIVE: To assess primary care providers' perspectives on online weight-loss programs.

METHODS: We conducted focus group discussions with providers in family medicine, internal medicine, and combined internal medicine/pediatrics in Texas and Pennsylvania, USA. Open-ended questions addressed their experience with and attitudes toward online weight-loss programs; useful characteristics of existing online weight-loss programs; barriers to referring patients to online weight-loss programs; and preferred characteristics of an ideal online weight-loss program. Transcripts were analyzed …

Polycyclic Aromatic Hydrocarbons In Maternal And Umbilical Cord Blood From Pregnant Hispanic Women Living In Brownsville, Texas, Ken Sexton, Jennifer J Salinas, Thomas J Mcdonald, Rose M Z Gowen, Rebecca P Miller, Joseph B Mccormick, Susan P Fisher-Hoch

Faculty, Staff and Student Publications

Venous blood was drawn from 35 pregnant Hispanic women living in Brownsville, Texas, and matched cord blood was collected at birth. Gas chromatography/mass spectrometry was used to measure concentrations of 55 individual PAHs or groups of PAHs. Results indicate that these women and their fetuses were regularly exposed to multiple PAHs at comparatively low concentrations, with levels in cord blood generally exceeding levels in paired maternal blood. While the possibility of related adverse effects on the fetus is uncertain, these exposures in combination with socioeconomically-disadvantaged and environmentally-challenging living conditions raise legitimate public health concerns.

Aua Guideline For The Diagnosis And Treatment Of Interstitial Cystitis/Bladder Pain Syndrome, Philip M Hanno, David Allen Burks, J Quentin Clemens, Roger R Dmochowski, Deborah Erickson, Mary Pat Fitzgerald, John B Forrest, Barbara Gordon, Mikel Gray, Robert Dale Mayer, Diane Newman, Leroy Nyberg, Christopher K Payne, Ursula Wesselmann, Martha M Faraday

Faculty, Staff and Student Publications

PURPOSE: To provide a clinical framework for the diagnosis and treatment of interstitial cystitis/bladder pain syndrome.

MATERIALS AND METHODS: A systematic review of the literature using the MEDLINE® database (search dates 1/1/83-7/22/09) was conducted to identify peer reviewed publications relevant to the diagnosis and treatment of interstitial cystitis/bladder pain syndrome. Insufficient evidence-based data were retrieved regarding diagnosis and, therefore, this portion of the Guideline is based on Clinical Principles and Expert Opinion statements. The review yielded an evidence base of 86 treatment articles after application of inclusion/exclusion criteria. These publications were used to create the majority of the treatment portion …

Multicentric Hepatic Ebv-Associated Smooth Muscle Tumors In An Aids Patient: A Case Report, Investigation Of Mtor Activation And Review Of The Literature, Qi Shen, Wei Feng, Michael S Long, Xiuzhen Duan, Siraya Jaijakul, Cesar A Arias, Robert E Brown, Bihong Zhao

Faculty, Staff and Student Publications

Epstein-Barr virus (EBV) - associated smooth muscle tumors (EBV-SMT) are a rare, recently recognized distinct group of mesenchymal tumors that develop exclusively in patients with immunosuppression. It is believed that tumorigenesis is, at least in part, through the activation of the Akt/mammalian target of rapamycin (mTOR) signal pathway. We describe the clinicopathologic and immunohistochemical features of a multifocal hepatic EBV-SMT in a 34-year-old acquired immunodeficiency syndrome (AIDS) patient and investigate the activation status of the mTOR signal pathway in this tumor. In addition, we provide a review of the literature on the clinicopathologic findings of hepatic EBV-SMT in adult AIDS …

Hepatocellular Carcinoma Survival In Uninsured And Underinsured Patients, John A Harvin, George Van Buren, Kuojen Tsao, Putao Cen, Tien C Ko, Curtis J Wray

Faculty, Staff and Student Publications

BACKGROUND: The incidence of hepatitis C virus (HCV) and hepatocellular carcinoma (HCC) is increasing. The purpose of this study is to establish baseline survival in a medically-underserved population and to evaluate the effect of HCV seropositivity on our patient population.

MATERIALS AND METHODS: We reviewed clinicopathologic parameters from a prospective tumor registry and medical records from the Harris County Hospital District (HCHD). Outcomes were compared using Kaplan-Meier survival analysis and log-rank tests.

RESULTS: A total of 298 HCC patients were identified. The median survival for the entire cohort was 3.4 mo. There was no difference in survival between the HCV …

Partial Volume Correction Incorporating Rb-82 Positron Range For Quantitative Myocardial Perfusion Pet Based On Systolic-Diastolic Activity Ratios And Phantom Measurements, Nils P Johnson, Stefano Sdringola, K Lance Gould

Faculty, Staff and Student Publications

BACKGROUND: Quantitative myocardial PET perfusion imaging requires partial volume corrections.

METHODS: Patients underwent ECG-gated, rest-dipyridamole, myocardial perfusion PET using Rb-82 decay corrected in Bq/cc for diastolic, systolic, and combined whole cycle ungated images. Diastolic partial volume correction relative to systole was determined from the systolic/diastolic activity ratio, systolic partial volume correction from phantom dimensions comparable to systolic LV wall thicknesses and whole heart cycle partial volume correction for ungated images from fractional systolic-diastolic duration for systolic and diastolic partial volume corrections.

RESULTS: For 264 PET perfusion images from 159 patients (105 rest-stress image pairs, 54 individual rest or stress images), …

Learning Curve For Robotic-Assisted Laparoscopic Colorectal Surgery, Malak B Bokhari, Chirag B Patel, Diego I Ramos-Valadez, Madhu Ragupathi, Eric M Haas

Faculty, Staff and Student Publications

BACKGROUND: Robotic-assisted laparoscopic surgery (RALS) is evolving as an important surgical approach in the field of colorectal surgery. We aimed to evaluate the learning curve for RALS procedures involving resections of the rectum and rectosigmoid.

METHODS: A series of 50 consecutive RALS procedures were performed between August 2008 and September 2009. Data were entered into a retrospective database and later abstracted for analysis. The surgical procedures included abdominoperineal resection (APR), anterior rectosigmoidectomy (AR), low anterior resection (LAR), and rectopexy (RP). Demographic data and intraoperative parameters including docking time (DT), surgeon console time (SCT), and total operative time (OT) were analyzed. …

Progenitor Cells As Remote "Bioreactors": Neuroprotection Via Modulation Of The Systemic Inflammatory Response, Peter A Walker, Phillip A Letourneau, Supinder Bedi, Shinil K Shah, Fernando Jimenez, Charles S Cox Jr

Faculty, Staff and Student Publications

Acute central nervous system (CNS) injuries such as spinal cord injury, traumatic brain injury, autoimmune encephalomyelitis, and ischemic stroke are associated with significant morbidity, mortality, and health care costs worldwide. Preliminary research has shown potential neuroprotection associated with adult tissue derived stem/progenitor cell based therapies. While initial research indicated that engraftment and transdifferentiation into neural cells could explain the observed benefit, the exact mechanism remains controversial. A second hypothesis details localized stem/progenitor cell engraftment with alteration of the loco-regional milieu; however, the limited rate of cell engraftment makes this theory less likely. There is a growing amount of preclinical data …

Molecular Mechanism By Which The Nucleoid Occlusion Factor, Slma, Keeps Cytokinesis In Check, Nam Ky Tonthat, Stefan T Arold, Brian F Pickering, Michael W Van Dyke, Shoudan Liang, Yue Lu, Tushar K Beuria, William Margolin, Maria A Schumacher

Faculty, Staff and Student Publications

In Escherichia coli, cytokinesis is orchestrated by FtsZ, which forms a Z-ring to drive septation. Spatial and temporal control of Z-ring formation is achieved by the Min and nucleoid occlusion (NO) systems. Unlike the well-studied Min system, less is known about the anti-DNA guillotining NO process. Here, we describe studies addressing the molecular mechanism of SlmA (synthetic lethal with a defective Min system)-mediated NO. SlmA contains a TetR-like DNA-binding fold, and chromatin immunoprecipitation analyses show that SlmA-binding sites are dispersed on the chromosome except the Ter region, which segregates immediately before septation. SlmA binds DNA and FtsZ simultaneously, and the …

Hypertensive Nephropathy Treatment By Heart-Protecting Musk Pill: A Study Of Anti-Inflammatory Therapy For Target Organ Damage Of Hypertension, Dengke Tian, Shuang Ling, Gangling Chen, Yajuan Li, Jun Liu, Murad Ferid, Ka Bian

Faculty, Staff and Student Publications

This study was designed to investigate the protective effect of the heart-protecting musk pill (HMP) on inflammatory injury of kidney from spontaneously hypertensive rat (SHR). Male SHRs aged 4 weeks were divided into SHR model group, HMP low-dosage group (13.5 mg/kg), and HMP high-dosage group (40 mg/kg). Age-matched Wistar-Kyoto rats were used as normal control. All rats were killed at 12 weeks of age. Tail-cuff method and enzyme-linked immunosorbent assay were used to determine rat systolic blood pressure and angiotensin II (Ang II) contents, respectively. Renal inflammatory damage was evaluated by the following parameters: protein expressions of inflammatory cytokines, carbonyl …

Spinal Cord Protection: Lessons Learned From Endovascular Repair, Jennifer N Dulin, Meredith L Moore, Kevin W Gates, Joanna H Queen, Raymond J Grill

Faculty, Staff and Student Publications

There is a high incidence of infertility in males following traumatic spinal cord injury (SCI). Quality of semen is frequently poor in these patients, but the pathophysiological mechanism(s) causing this are not known. Blood-testis barrier (BTB) integrity following SCI has not previously been examined. The objective of this study was to characterize the effects of spinal contusion injury on the BTB in the rat. 63 adult, male Sprague Dawley rats received SCI (n = 28), laminectomy only (n = 7) or served as uninjured, age-matched controls (n = 28). Using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), BTB permeability to the …

The Hypoxia-Adenosine Link During Myocardial Ischemia—Reperfusion Injury, Diana Panesso, Maria C Montealegre, Sandra Rincón, Maria F Mojica, Louis B Rice, Kavindra V Singh, Barbara E Murray, Cesar A Arias

Faculty, Staff and Student Publications

BACKGROUND: Plasmids containing hylEfm (pHylEfm) were previously shown to increase gastrointestinal colonization and lethality of Enterococcus faecium in experimental peritonitis. The hylEfm gene, predicting a glycosyl hydrolase, has been considered as a virulence determinant of hospital-associated E. faecium, although its direct contribution to virulence has not been investigated. Here, we constructed mutants of the hylEfm-region and we evaluated their effect on virulence using a murine peritonitis model.

RESULTS: Five mutants of the hylEfm-region of pHylEfmTX16 from the sequenced endocarditis strain (TX16 [DO]) were obtained using an adaptation of the PheS* system and were evaluated in a commensal strain TX1330RF to …

Probing The Mechanical Properties Of Tnf-A Stimulated Endothelial Cell With Atomic Force Microscopy, Sei-Young Lee, Ana-Maria Zaske, Tommaso Novellino, Delia Danila, Mauro Ferrari, Jodie Conyers, Paolo Decuzzi

Faculty, Staff and Student Publications

TNF-α (tumor necrosis factor-α) is a potent pro-inflammatory cytokine that regulates the permeability of blood and lymphatic vessels. The plasma concentration of TNF-α is elevated (> 1 pg/mL) in several pathologies, including rheumatoid arthritis, atherosclerosis, cancer, pre-eclampsia; in obese individuals; and in trauma patients. To test whether circulating TNF-α could induce similar alterations in different districts along the vascular system, three endothelial cell lines, namely HUVEC, HPMEC, and HCAEC, were characterized in terms of 1) mechanical properties, employing atomic force microscopy; 2) cytoskeletal organization, through fluorescence microscopy; and 3) membrane overexpression of adhesion molecules, employing ELISA and immunostaining. Upon stimulation …

Complete Genome Sequence Of Treponema Paraluiscuniculi, Strain Cuniculi A: The Loss Of Infectivity To Humans Is Associated With Genome Decay, David Smajs, Marie Zobaníková, Michal Strouhal, Darina Cejková, Shannon Dugan-Rocha, Petra Pospíšilová, Steven J Norris, Tom Albert, Xiang Qin, Kym Hallsworth-Pepin, Christian Buhay, Donna M Muzny, Lei Chen, Richard A Gibbs, George M Weinstock

Faculty, Staff and Student Publications

Treponema paraluiscuniculi is the causative agent of rabbit venereal spirochetosis. It is not infectious to humans, although its genome structure is very closely related to other pathogenic Treponema species including Treponema pallidum subspecies pallidum, the etiological agent of syphilis. In this study, the genome sequence of Treponema paraluiscuniculi, strain Cuniculi A, was determined by a combination of several high-throughput sequencing strategies. Whereas the overall size (1,133,390 bp), arrangement, and gene content of the Cuniculi A genome closely resembled those of the T. pallidum genome, the T. paraluiscuniculi genome contained a markedly higher number of pseudogenes and gene fragments (51). In …

Alterations In Content And Localization Of Defensins In Rat Ileum And Jejunum Following Ischemia-Reperfusion Specific Peptides, In Specific Places, For Specific Jobs?, Rosemary A Kozar, Rachel J Santora, Brian J Poindexter, Stephen M Milner, Roger J Bick

Faculty, Staff and Student Publications

Objective: To determine alterations in quantities and distributions of natural antimicrobials following ischemia-reperfusion injury. We hypothesized that these compounds would be upregulated in areas of small intestine where changes in permeability and cellular disruption were likely and where protective mechanisms would be initiated. Methods: Rats with ischemia-reperfusion underwent superior mesenteric artery clamping and reperfusion. Shams were subjected to laparotomy but no clamping. Ileum and jejunum were harvested and sectioned, and subjected to fluorescence deconvolution microscopy for determinations of content and localization of rat beta defensins, 1, 2, 3; rat neutrophil protein-1; and cathelicidin LL-37. Modeling was performed to determine cellular …

Measuring The Symptom Burden Of Lung Cancer: The Validity And Utility Of The Lung Cancer Module Of The M D Anderson Symptom Inventory, Tito R Mendoza, Xin Shelley Wang, Charles Lu, Guadalupe R Palos, Zhongxing Liao, Gary M Mobley, Shitij Kapoor, Charles S Cleeland

Faculty, Staff and Student Publications

We conducted a study to establish the psychometric properties of a module of the M. D. Anderson Symptom Inventory (MDASI) developed specifically for patients with lung cancer (MDASI-LC). The MDASI measures 13 common "core" symptoms of cancer and its treatment. The MDASI-LC includes the 13 core MDASI symptom items and three lung cancer-specific items: coughing, constipation, and sore throat. MDASI-LC items were administered to three cohorts of patients with lung cancer undergoing either chemotherapy or chemoradiotherapy. Known-group validity and criterion (concurrent) validity of the MDASI-LC were evaluated using the Eastern Cooperative Oncology Group performance status and the 12-item Short-Form Health …

Association Of Retinoic Acid Receptor Genes With Meningomyelocele, Phong X Tran, Kit Sing Au, Alanna C Morrison, Jack M Fletcher, Kathryn K Ostermaier, Gayle H Tyerman, Hope Northrup

Faculty, Staff and Student Publications

BACKGROUND: Neural tube defects (NTDs) occur in as many as 0.5-2 per 1000 live births in the United States. One of the most common and severe neural tube defects is meningomyelocele (MM) resulting from failed closure of the caudal end of the neural tube. MM has been induced by retinoic acid teratogenicity in rodent models. We hypothesized that genetic variants influencing retinoic acid (RA) induction via retinoic acid receptors (RARs) may be associated with risk for MM.

METHODS: We analyzed 47 single nucleotide polymorphisms (SNPs) that span across the three retinoic acid receptor genes using the SNPlex genotyping platform. Our …

Immunopathology Of Postprimary Tuberculosis: Increased T-Regulatory Cells And Dec-205-Positive Foamy Macrophages In Cavitary Lesions, Kerry J Welsh, Semyon A Risin, Jeffrey K Actor, Robert L Hunter

Faculty, Staff and Student Publications

Postprimary tuberculosis occurs in immunocompetent people infected with Mycobacterium tuberculosis. It is restricted to the lung and accounts for 80% of cases and nearly 100% of transmission. Little is known about the immunopathology of postprimary tuberculosis due to limited availability of specimens. Tissues from 30 autopsy cases of pulmonary tuberculosis were located. Sections of characteristic lesions of caseating granulomas, lipid pneumonia, and cavitary stages of postprimary disease were selected for immunohistochemical studies of macrophages, lymphocytes, endothelial cells, and mycobacterial antigens. A higher percentage of cells in lipid pneumonia (36.1%) and cavitary lesions (27.8%) were positive for the dendritic cell marker …

Chondrosarcoma Of The Mobile Spine And Sacrum, Ryan M Stuckey, Rex A W Marco

Faculty, Staff and Student Publications

Chondrosarcoma is a rare malignant tumor of bone. This family of tumors can be primary malignant tumors or a secondary malignant transformation of an underlying benign cartilage tumor. Pain is often the initial presenting complaint when chondrosarcoma involves the spine. In the mobile spine, chondrosarcoma commonly presents within the vertebral body and shows a predilection for the thoracic spine. Due to the resistance of chondrosarcoma to both radiation and chemotherapy, treatment is focused on surgery. With en bloc excision of chondrosarcoma of the mobile spine and sacrum patients can have local recurrence rates as low as 20%.

Case Of “Slow” Stroke From Carotid Artery Occlusion Treated By Delayed But Cautious Endovascular Intervention, Kachi Illoh, Emilio Supsupin, Hashem M Shaltoni, Edwin D Cacayorin

Faculty, Staff and Student Publications

In a challenging case of carotid occlusion with slowly evolving stroke, we used brain imaging to facilitate endovascular revascularization resulting in the relief of the patient's symptoms. Patients with carotid occlusion and continued neurological worsening or fluctuations present enormous treatment challenges. These patients may present "slow" strokes with subacute infarcts that present significant challenges and risks during attempts at revascularization of the occluded artery. We present such a case in which we used multimodal imaging techniques, including MR-perfusion, to facilitate endovascular revascularization. Our approach of delayed but cautious intra-arterial thrombolytic therapy, guided by brain imaging, and followed by stent placement …

Enterococcus Faecalis Rnjb Is Required For Pilin Gene Expression And Biofilm Formation, Peng Gao, Kenneth L Pinkston, Sreedhar R Nallapareddy, Ambro Van Hoof, Barbara E Murray, Barrett R Harvey

Faculty, Staff and Student Publications

Pili in Gram-positive bacteria play a major role in the colonization of host tissue and in the development of biofilms. They are promising candidates for vaccines or drug targets since they are highly immunogenic and share common structural and functional features among various Gram-positive pathogens. Numerous publications have helped build a detailed understanding of pilus surface assembly, yet regulation of pilin gene expression has not been well defined. Utilizing a monoclonal antibody developed against the Enterococcus faecalis major pilus protein EbpC, we identified mutants from a transposon (Tn) insertion library which lack surface-exposed Ebp pili. In addition to insertions in …

Histamine Reduces Flash Sensitivity Of On Ganglion Cells In The Primate Retina, Nikolay P Akimov, David W Marshak, Laura J Frishman, Randolph D Glickman, Rafail G Yusupov

Faculty, Staff and Student Publications

PURPOSE. In Old World primates, the retina receives input from histaminergic neurons in the posterior hypothalamus. They are a subset of the neurons that project throughout the central nervous system and fire maximally during the day. The contribution of these neurons to vision, was examined by applying histamine to a dark-adapted, superfused baboon eye cup preparation while making extracellular recordings from peripheral retinal ganglion cells. METHODS. The stimuli were 5-ms, 560-nm, weak, full-field flashes in the low scotopic range. Ganglion cells with sustained and transient ON responses and two cell types with OFF responses were distinguished; their responses were recorded …

A Direct Role For Secretory Phospholipase A2 And Lyso-Phosphatidylcholine In The Mediation Of Lipopolysaccharide-Induced Gastric Injury, Elizabeth J Dial, Duy M Tran, Jimmy J Romero, Mayssa Zayat, Lenard M Lichtenberger

Faculty, Staff and Student Publications

Endotoxemia from sepsis can injure the gastrointestinal tract through mechanisms that have not been fully elucidated. We have shown that LPS induces an increase in gastric permeability in parallel with the luminal appearance of secretory phospholipase A2 (sPLA2) and its product, lysophosphatidylcholine (lyso-PC). We proposed that sPLA2 acted on the gastric hydrophobic barrier, composed primarily of phosphatidylcholine (PC), to degrade it and produce lyso-PC, an agent that is damaging to the mucosa. In the present study, we have tested whether lyso-PC and/or sPLA2 have direct damaging effects on the hydrophobic barriers of synthetic and mucosal surfaces. Rats were administered LPS …