Microbiology Commons^™

Role Of Mhc Antigens And Immunoregulation In Graft Survival In Autoimmunity, Bhagirath Singh

Microbiology & Immunology Publications

Using a syngeneic islet transplantation model system we have showed that in autoimmune type 1 diabetes transplanted islets are destroyed by the host immune system unless the transplanted islets lack class I major histocompatibility complex (MHC) molecules. Alternatively, immunomodulation of the host by induction of regulatory T cells prevented the destruction of autologous islet graft. We conclude that these approaches will allow successful transplantation of autologous islets derived from the host by stem cell or other technology without immunosuppression to reverse autoimmune type 1 diabetes.

Morphological And Molecular Analyses Of Microorganisms In Caribbean Reef Adult Sponges And In Corresponding Reproductive Material, Susanne Schmitt, Markus Wehrl, Niels Lindquist, Jeremy B. Weisz, Ute Hentschel

Faculty Publications

Caribbean reef sponges were surveyed for the presence of microorganisms in the mesohyl tissue of adult sponges and the respective reproductive material (embryos, larvae). A clear correlation was found in that high microbial abundance (HMA) sponges always contained microorganisms in their reproductive stages. In contrast, low microbial abundance (LMA) sponges did not contain microorganisms in their reproductive stages. Based on these data, Ircinia felix Duchassaing and Michelotti, 1864 was chosen as a model organism for the molecular analysis of microorganisms within the adult sponge and its larvae and juveniles. Denaturing gradient gel electrophoresis (DGGE) of eubacterial 16S rDNA sequences revealed …

Vertical Transmission Of A Phylogenetically Complex Microbial Consortium In The Viviparous Sponge Ircinia Felix, Susanne Schmitt, Jeremy B. Weisz, Niels Lindquist, Ute Hentschel

Faculty Publications

Many marine demosponges contain large amounts of phylogenetically complex yet highly sponge-specific microbial consortia within the mesohyl matrix, but little is known about how these microorganisms are acquired by their hosts. Settlement experiments were performed with the viviparous Caribbean demosponge Ircinia felix to investigate the role of larvae in the vertical transmission of the sponge-associated microbial community. Inspections by electron microscopy revealed large amounts of morphologically diverse microorganisms in the center of I. felix larvae, while the outer rim appeared to be devoid of microorganisms. In juveniles, microorganisms were found between densely packed sponge cells. Denaturing gradient gel electrophoresis (DGGE) …

Poxviral B1 Kinase Overcomes Barrier To Autointegration Factor, A Host Defense Against Virus Replication, Matthew S. Wiebe, Paula Traktman

Nebraska Center for Virology: Faculty Publications

Barrier to autointegration factor (BAF) is a DNA-binding protein found in the nucleus and cytoplasm of eukaryotic cells that functions to establish nuclear architecture during mito-sis. Herein, we demonstrate a cytoplasmic role for BAF in host defense during poxviral infections. Vaccinia is the prototypic poxvirus, a family of DNA viruses that replicate ex-clusively in the cytoplasm of infected cells. Mutations in the vaccinia B1 kinase (B1) com-promise viral DNA replication, but the mechanism by which B1 achieves this has remained elusive. We now show that BAF acts as a potent inhibitor of poxvirus replication unless its DNA-binding activity is blocked …

Environmental Controls On The Landscape-Scale Biogeography Of Stream Bacterial Communities, Noah Fierer, Jennifer L. Morse, Sean T. Berthrong, Emily S. Bernhardt, Robert B. Jackson

Scholarship and Professional Work - LAS

We determined the biogeographical distributions of stream bacteria and the biogeochemical factors that best explained heterogeneity for 23 locations within the Hubbard Brook watershed, a 3000-ha forested watershed in New Hampshire, USA. Our goal was to assess the factor, or set of factors, responsible for generating the biogeographical patterns exhibited by microorganisms at the landscape scale. We used DNA fingerprinting to characterize bacteria inhabiting fine benthic organic matter (FBOM) because of their important influence on stream nutrient dynamics. Across the watershed, streams of similar pH had similar FBOM bacterial communities. Streamwater pH was the single variable most strongly correlated with …

Evolutionary Endocrinology: The Developing Synthesis Between Endocrinology And Evolutionary Genetics, Anthony J. Zera, Lawrence G. Harshman, Tony D. Williams

Anthony Zera Publications

A productive synthesis of endocrinology and evolutionary genetics has occurred during the past two decades, resulting in the first direct documentation of genetic variation and correlation for endocrine regulators in nondomesticated animals. In a number of insect genetic polymorphisms (dispersal polymorphism in crickets, butterfly wing-pattern polymorphism), blood levels of ecdysteroids and juvenile hormone covary with morphology, development, and life history. Genetic variation in insulin signaling may underlie life history trade-offs in Drosophila. Vertebrate studies identified variation in brain neurohormones, bone-regulating hormones, and hormone receptor gene sequences that underlie ecologically important genetic polymorphisms. Most work to date has focused on genetically …

Sulfur-Oxidizing Bacteria In Soap Lake (Washington State), A Meromictic, Haloalkaline Lake With An Unprecedented High Sulfide Content, Dimitry Y. Sorokin, Mirjam Foti, Holly C. Pinkart, Gerard Muyzer

All Faculty Scholarship for the College of the Sciences

Culture-dependent and -independent techniques were used to study the diversity of chemolithoautotrophic sulfur-oxidizing bacteria in Soap Lake (Washington State), a meromictic, haloalkaline lake containing an unprecedentedly high sulfide concentration in the anoxic monimolimnion. Both approaches revealed the dominance of bacteria belonging to the genus Thioalkalimicrobium, which are common inhabitants of soda lakes. A dense population of Thioalkalimicrobium (up to 10⁷ cells/ml) was found at the chemocline, which is characterized by a steep oxygen-sulfide gradient. Twelve Thioalkalimicrobium strains exhibiting three different phenotypes were isolated in pure culture from various locations in Soap Lake. The isolates fell into two groups …

Aids-Associated Viral Oncogenesis: Overview, Charles Wood

Nebraska Center for Virology: Faculty Publications

It has been 25 years since the acquired immunodeficiency syndrome (AIDS) was first described and over 23 years since the human immunodeficiency virus (HIV) associated with the disease was first discovered. In spite of the tremendous progress that was made in understanding both the disease and the virus, there are still millions of people infected, died, or living with the disease. As for the year 2005 alone, the Joint United Nations Programme on HIV/AIDS (http://www.UNAIDS.org) estimates that there are about 40 million people living with HIV/AIDS globally, and approximately 3 million people died from AIDS in the year. Globally, it …

Modulation Of Retroviral Restriction And Proteasome Inhibitor-Resistant Turnover By Changes In The Trim5Α B-Box 2 Domain, Felipe Diaz-Griffero, Alak Kar, Michel Perron, Shi-Hua Xiang, Hassan Javanbakht, Xing Li, Joseph Sodroski

Nebraska Center for Virology: Faculty Publications

An intact B-box 2 domain is essential for the antiretroviral activity of TRIM5α. We modeled the structure of the B-box 2 domain of TRIM5α based on the existing three-dimensional structure of the B-box 2 domain of human TRIM29. Using this model, we altered the residues predicted to be exposed on the surface of this globular structure. Most of the alanine substitutions in these residues exerted little effect on the antiretroviral activity of human TRIM5αhu or rhesus monkey TRIM5α_rh. However, alteration of arginine 119 of TRIM5α_hu or the corresponding arginine 121 of TRIM5α_rh diminished the abilities of …

Viral Diseases Of The Fetus, Clayton L. Kelling

Nebraska Center for Virology: Faculty Publications

Bovine viral diarrhea virus (BVDV) is one of the most commonly encountered and economically important pathogens of cattle in North America. Since the mid-20th century, BVDV has been recognized as a significant cause of disease of the gastrointestinal system. The impact of BVDV on reproduction was not perceived for another 30 years, when the occurrence of persistent infection in imunotolerant cattle was described.

BVDV infections may occur in cattle as acute illness- that is, bovine viral diarrhea (BVD)-or as a generally chronic condition-mucosal disease. When susceptible regnant cattle are infected with BVDV, transplacental infections usually occur. Transplacental infections may lead …

Prion Interference Is Due To A Reduction In Strain-Specific PrpSc Levels, Jason C. Bartz, Michelle L. Kramer, Meghan H. Sheehan, Jessica A. L. Hutter, Jacob I. Ayers, Richard A. Bessen, Anthony E. Kincaid

Nebraska Center for Virology: Faculty Publications

When two prion strains infect a single host, one strain can interfere with the ability of the other to cause disease but it is not known whether prion replication of the second strain is also diminished. To further investigate strain interference, we infected hamsters in the sciatic nerve with the long-incubation-period transmissible mink encephalopathy (TME) agent DY TME prior to superinfection of hamsters with the short-incubation-period HY TME agent. Increases in the interval between TME agent inoculations resulted in an extension of the incubation period of HY TME or a complete block of the ability of the HY TME agent …

Traditional Practices And Exposure To Bodily Fluids In Lusaka, Zambia, Janet M. Wojcicki, Chipepo Kankasa, Charles Mitchell, Charles Wood

Papers in Virology

Objectives To ascertain if there are specific sociocultural and behavioral practices associated with the exposure to saliva, semen and vaginal fluids, particularly through child-rearing practices and the use of traditional medicine in Lusaka, Zambia. Methods We conducted 11 focus group discussions with men and women from diverse ethnic and socioeconomic backgrounds (n = 105) in Lusaka, Zambia in March 2004. We also conducted a brief sociodemographic survey of all focus group participants. Results Discussions indicated that saliva was used while engaging in home health care practices associated with childcare and the use of traditional medicine. Additionally, semen and vaginal …

Hypoxic Induction And The Role Of Hifs In The Activation Of Luciferase Constitutive Reporters In Placental Stem Cells, Diane Michelle Doran

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Hypoxia is critically important to the development of the embryo and placenta. Proper placental development is critical for normal fetal growth and embryonic survival. Abnormal placental development has been implicated in numerous obstetric complications, including preeclampsia, which affects about 7% of all pregnancies and can be fatal for both mother and baby. Rodent and murine trophoblast stem cells differentiate into three distinct cell lineages: giant cells, spongiotrophoblasts, and labyrinthine cells, which form different layers and have different functions within the placenta. Recent studies in our laboratory have focused on the invasive giant cell layer using the rodent Rcho-1 choriocarcinoma stem …

On A Multinational Assessment Of Rotavirus Disease In Europe, David O. Matson

Community & Environmental Health Faculty Publications

Rotaviruses were discovered in the 1960s in animals and in the 1970s in humans; the latter discovery was made by an intrepid group who performed duodenal biopsies on children with acute gastroenteritis (AGE) [1]. By the late 1970s, data already clearly indicated that rotavirus was the cause of the annual winter peak of AGE affecting young children, as well as a frequent cause of severe gastroenteritis in various animal species (e.g., [2–5]). Use of the retrospectroscope clarified or left as tantalizing the suggestion that rotaviruses were the cause of the annual “winter vomiting syndrome” first described in children in 1910 …

Potential For Stimulating Host Anti-Tumor Immune Response Via Rnai-Mediated Local Foxp3 Knockdown, N. Klaiber

Chemistry & Biochemistry Faculty Publications

Neoplastic growths represent a unique challenge for the host immune system. As they are indeed derived from self, many of the same mechanisms operating to prevent autoimmunity also provide an umbrella beneath which malignant cells are free to proliferate.1 Central among these immune regulatory boundaries are an influential subset of lymphocytes known as T regs. Hypothesized to exist decades ago, yet eluding definitive characterization until relatively recently, T regs have been demonstrated to play a crucial role in the proper functioning of the immune system as a whole. They may also, however, represent one of the primary obstacles to successful …

Mutations In Transmembrane Domains 1, 4 And 9 Of The Plasmodium Falciparum Chloroquine Resistance Transporter Alter Susceptibility To Chloroquine, Quinine And Quinidine, Roland A. Cooper, Kristan D. Lane, Bingbing Deng, Jianbing Mu, Jigar J. Patel, Thomas E. Wellems, Xinzhuan Su, Michael T. Ferdig

Biological Sciences Faculty Publications

Mutations in the Plasmodium falciparum chloroquine (CQ) resistance transporter (PfCRT) can result in verapamil-reversible CQ resistance and altered susceptibility to other antimalarials. PfCRT contains 10 membrane-spanning domains and is found in the digestive vacuole (DV) membrane of intraerythrocytic parasites. The mechanism by which PfCRT mediates CQ resistance is unclear although it is associated with decreased accumulation of drug within the DV. On the permissive background of the P. falciparum 106/1(K76) parasite line, we used single-step drug selection to generate isogenic clones containing unique pfcrt point mutations that resulted in amino acid changes in PfCRT transmembrane domains 1 (C72R, K76N, K76I …

Humboldt Journal Of Microbiology: Volume 9, Number 1- May 2007, Press Humboldt

Humboldt Journal of Microbiology

No abstract provided.

Comparison Study Of The Averaged Sediment Microbial Enzyme Activities In Four Fecally-Contaminated Streams In The Same Watershed In Northeast Tennessee To Biochemical Oxygen Demand, Nitrate Concentration, And Phosphate Concentration, Brian G. Evanshen, Kurt J. Maier, Phillip R. Scheuerman

ETSU Faculty Works

Microbial enzyme activities (MEA’s) are measurements of microbial metabolism. These activities are dependent on the need for nutrients and respiration. This extended study evaluated four streams in the same watershed that had an approved fecal coliform Total Maximum Daily Load. Sediment and water samples were collected monthly for the first year of each specific stream study, and then quarterly to the end of 2006. Dehydrogenase, a measure of microbial respiration, along with acid phosphatase, alkaline phosphatase, galactosidase and glucosidase activities were measured using colorimetric assays. Biochemical oxygen demand (BOD) was determined using the standard 5-day test (BOD₅). Nitrate …

Chemical Defenses: From Compounds To Communities, Valerie J. Paul, Koty H. Sharp

Arts & Sciences Faculty Publications

Marine natural products play critical roles in the chemical defense of many marine organisms and in some cases can influence the community structure of entire ecosystems. Although many marine natural products have been studied for biomedical activity, yielding important information about their biochemical effects and mechanisms of action, much less is known about ecological functions. The way in which marine consumers perceive chemical defenses can influence their health and survival and determine whether some natural products persist through a food chain. This article focuses on selected marine natural products, including okadaic acid, brevetoxins, lyngbyatoxin A, caulerpenyne, bryostatins, and isocyano terpenes, …

Characteristics Of A Foamy Virus-Derived Vector That Allow For Safe Autologous Gene Therapy To Correct Leukocyte Adhesion Deficiency Type 1, Ryan Matthew Mcnichol

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The hematopoeitic stem cell is a prime target for gene therapy in the attempt to correct a number of single gene inherited genetic defects that affect the immune system. In persons affected by leukocyte adhesion deficiency type 1 (LAD-1) the gene for the Beta-2 subunit of the integrin molecule is mutated. This autosomal recessive gene defect yields a phenotype with little or no beta-2 integrin expression on leukocytes. Beta-2 integrin expression is essential for leukocytes to travel from the blood to the tissues to fight infection. Persons with this disease have lowered leukocyte counts in the tissues and as a …

Hsv-1 Infection Of C3h Central Nervous System Cell Lines, Lauren Kay Van Buren

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Herpes Simplex Virus Type 1 (HSV-1) can infect the nervous system, resulting in a disease known as herpes encephalitis (HSE). Herpes encephalitis affects thousands of people each year; many cases are fatal or permanently debilitating. Approximately two thousand known cases occur in the United States each year alone (Neuroland online source). Acyclovir has been the drug of choice used to treat herpes encephalitis. Even after the administration of acyclovir, permanent neurological damage and/or death often results. Thousands of individuals would benefit by the discovery of drugs that are more effective at preventing lasting HSE damage and death. Knowledge concerning HSE …

Discovery Of New Antimicrobial Agents Using Combinatorial Chemistry, William I. Northern

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Combinatorial chemistry has become an important aspect of medicinal research due to its flexibility and the ability to produce large numbers of potential therapeutic agents. Once compounds are made, they must be screened to determine if there is any biological activity. This research project focused on developing a screening method for chemical agents produced by a graduate student in the chemistry department at Wright State University. After an acceptable screening method was found, the goal of the project was to determine if compounds produced had either antibacterial activity, antifungal activity, or both. Seven compounds exhibited biological activity. Two of these …

A Protein Encoded By The Bovine Herpesvirus 1 Latency-Related Gene Interacts With Specific Cellular Regulatory Proteins, Including Ccaat Enhancer Binding Protein Alpha, Florencia Meyer, Sandra Perez, Vicki Geiser, Mark Sintek, Melissa Inman, Clinton J. Jones

Nebraska Center for Virology: Faculty Publications

Following acute infection, bovine herpesvirus 1 establishes latency in sensory neurons of trigeminal ganglia (TG). Reactivation from latency occurs periodically, resulting in the shedding of infectious virus. The latency-related (LR) RNA is abundantly expressed in TG of latently infected calves, and the expression of LR proteins is necessary for dexamethasone-induced reactivation from latency. Previously published studies also identified an alternatively spliced LR transcript which is abundantly expressed in TG at 7 days after infection and has the potential to encode a novel LR fusion protein. Seven days after infection is when extensive viral gene expression is extinguished in TG and …

Genetic Microheterogeneity And Phenotypic Variation Of Helicobacter Pylori Arginase In Clinical Isolates, Justin Hovey, Emily Watson, Melanie Langford, Ellen Hildebrandt, Sangeetha Bathala, Jeffrey Bolland, Domenico Spadafora, George Mendz, David Mcgee

School of Biological Sciences: Faculty Publications

Background: Clinical isolates of the gastric pathogen Helicobacter pylori display a high level of genetic macro- and microheterogeneity, featuring a panmictic, rather than clonal structure. The ability of H. pylori to survive the stomach acid is due, in part, to the arginase-urease enzyme system. Arginase (RocF) hydrolyzes L-arginine to L-ornithine and urea, and urease hydrolyzes urea to carbon dioxide and ammonium, which can neutralize acid.

Results: The degree of variation in arginase was explored at the DNA sequence, enzyme activity and protein expression levels. To this end, arginase activity was measured from 73 minimally-passaged clinical isolates and six laboratory-adapted strains …

Sensory Genes And Mate Choice: Evidence That Duplications, Mutations, And Adaptive Evolution Alter Variation In Mating Cue Genes And Their Receptors, Lisa Horth

Biological Sciences Faculty Publications

Fascinating new data, revealed through gene sequencing, comparative genomics, and genetic engineering, precisely establish which genes are involved in mate choice and mating activity—behaviors that are surprisingly understudied from a genetic perspective. Discussed here are some of the recently identified visual and chemosensory genes that are involved in mate choice and mating behavior. These genes’ products are involved in the production, transmission, and receipt of crucial sensory mate-choice cues that affect fitness. This review exposes newfound evidence that alternative splicing, gene-expression pattern changes, and molecular genetic variation in sensory genes are crucial for both intra- and interspecific mate choice and …

Characterization Of Mycobacterium Tuberculosis Central Asian Strain 1 Using Mycobacterial Interspersed Repetitive Unit Genotyping, Asho Ali, Zahra Hasan, Mahnaz Tanveer, Amna Siddiqui, Solomon Ghebremichael, Gunilla Kallenius, Rumina Hasan

Department of Pathology and Laboratory Medicine

Background:
The Central Asian Strain1 (CAS1) genogroup of Mycobacterium tuberculosis (MTB) is the most prevalent in Pakistan, India and Bangladesh. Mycobacterial interspersed repetitive units variable number tandem repeat (MIRU-VNTR) typing is a reliable and reproducible method for differentiation of MTB isolates. However, information of its utility in determining the diversity of CAS1 strain is limited. We performed standard 12 loci based MIRU-VNTR typing on previously spoligotyped CAS1 strains and 'unique' strains in order to evaluate its discriminatory power for these isolates.
Methods:
Twelve loci based MIRU- VNTR typing was used to type178 CAS1 and 189 'unique' MTB strains. The discriminatory …

Comparative Predictive Value Of Three Prognostic Markers--S-Phase Fraction, Pcna And Mitotic Count On Axillary Lymph Node Metastasis In Carcinoma Breast, Shahid Pervez, Muhammad Nadeem Khan, Muhammad Israr Nasir

Department of Pathology and Laboratory Medicine

Background: Axillary lymph node metastasis is the single most important prognostic factor in carcinoma of the breast. Therefore, prognostic markers that may reliably predict probability of lymph node (LN) metastases are of great value. This study was conducted to compare the predictive value of two novel prognostic / proliferative markers i.e. S-phase fraction (SPF) and proliferating cell nuclear antigen (PCNA) in parallel with mitotic index.

Methods: Data of consecutive cases of infiltrating ductal carcinoma (IDC) breast diagnosed from July 2003 to July 2004 at the section of the Histopathology, The Aga Khan University Hospital, Karachi, were reviewed. A total of …

Establishment And Maintenance Of An Asm Student Chapter, Amy Cheng Vollmer

Biology Faculty Works

No abstract provided.

Human Papillomavirus Prevalence And Genotypes In An Opportunistically Screened Irish Female Population, Helen Keegan, Fergus Ryan, Alison Malkin, Mairead Griffin, Helen Lambkin

Articles

This study aims to evaluate human papillomavirus (HPV) prevalence and predominating genotypes in liquid-based cervical cytology samples from an Irish urban female population. In addition to use of routine cervical cytology testing, women are screened for HPV using the MY09/11 primers for the HPV L1 gene and primers for β-globin amplification in a multiplex format. Overall, 996 women between the ages of 16 and 72 years (average age: 35) are included in the study and HPV prevalence was 19.8%. Cytology results showed that 88.9% were normal, 9% borderline or mild dyskaryosis, 1.1% moderate dyskaryosis and 0.9% severe dyskaryosis. Human papillomavirus …

Evaluation Of Four Novel Broad-Host-Range Antimicrobial Agents., Jiahui Guo

Theses

The overall objective of this thesis was to evaluate the antimicrobial effects of four novel broad-host-range antimicrobial agents. The first was a milk-derived lipoprotein developed by Westgate Biologicals with the support of Enterprise Ireland. This lipoprotein which was designated LactiSAL, was evaluated against a wide range of bacterial species associated with humans. Essentially, the LactiSAL was incorporated at a variety of concentrations into agar media, which were appropriate for cultivation of the different genera. Agars were examined for colony formation, after which it was possible to quantify the minimal inhibitory concentration for each genus. Subsequently, LactiSAL was incorporated at levels …