32 results on '"Leighty R"'
Search Results
2. Duplicate gene enrichment and expression pattern diversification in multicellularity
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Padawer, T., primary, Leighty, R. E., additional, and Wang, D., additional
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- 2012
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3. Kidney-Targeted Birt-Hogg-Dube Gene Inactivation in a Mouse Model: Erk1/2 and Akt-mTOR Activation, Cell Hyperproliferation, and Polycystic Kidneys
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Baba, M., primary, Furihata, M., additional, Hong, S.-B., additional, Tessarollo, L., additional, Haines, D. C., additional, Southon, E., additional, Patel, V., additional, Igarashi, P., additional, Alvord, W. G., additional, Leighty, R., additional, Yao, M., additional, Bernardo, M., additional, Ileva, L., additional, Choyke, P., additional, Warren, M. B., additional, Zbar, B., additional, Linehan, W. M., additional, and Schmidt, L. S., additional
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- 2008
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4. A diet high in omega-3 fatty acids does not improve or protect cognitive performance in Alzheimer’s transgenic mice
- Author
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Arendash, G.W., primary, Jensen, M.T., additional, Salem, N., additional, Hussein, N., additional, Cracchiolo, J., additional, Dickson, A., additional, Leighty, R., additional, and Potter, H., additional
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- 2007
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5. Auditory evoked potentials in schizophrenia
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Boutros, N., primary, Nasrallah, H., additional, Leighty, R., additional, Torello, M., additional, Tueting, P., additional, and Olson, S., additional
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- 1996
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6. Sequence analysis of Kaposi sarcoma-associated herpesvirus (KSHV) microRNAs in patients with multicentric Castleman disease and KSHV-associated inflammatory cytokine syndrome.
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Ray A, Marshall V, Uldrick T, Leighty R, Labo N, Wyvill K, Aleman K, Polizzotto MN, Little RF, Yarchoan R, Whitby D, Ray, Alex, Marshall, Vickie, Uldrick, Thomas, Leighty, Robert, Labo, Nazzarena, Wyvill, Kathy, Aleman, Karen, Polizzotto, Mark N, and Little, Richard F
- Abstract
Background: Kaposi sarcoma-associated herpesvirus (KSHV) encodes 12 pre-microRNAs that yield 25 mature microRNAs. We previously reported phylogenetic analysis of the microRNA-coding region of KSHV from Kaposi sarcoma (KS), primary effusion lymphoma (PEL), and multicentric Castleman disease (MCD) patients. We observed a high level of conservation for most sequences but also a divergent cluster of 5 KSHV sequences, including 2 from MCD patients.Methods: KSHV microRNA sequences from 23 MCD patients and 7 patients with a newly described KSHV-associated inflammatory cytokine syndrome (KICS) were examined by amplification, cloning, and sequencing of a 646-bp fragment of K12/T0.7 encoding microRNA-K12-10 and microRNA-K12-12 and a 2.8-kbp fragment containing the remaining 10 pre-microRNAs.Results: Phylogenetic analysis showed a distinct variant cluster consisting exclusively of MCD and KICS patients in all trees. Pearson χ(2) analysis revealed that 40 single-nucleotide polymorphisms (SNPs) at various loci were significantly associated with MCD and KICS risk. Cluster analysis of these SNPs generated several combinations of 3 SNPs as putative indicators of MCD and KICS risk.Conclusions: These findings show that MCD and KICS patients frequently have unusual KSHV microRNA sequences and suggest an association between the observed sequence variation and risk of MCD and KICS. [ABSTRACT FROM AUTHOR]- Published
- 2012
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7. Relationship of pregnancy to human papillomavirus among human immunodeficiency virus-infected women [corrected] [published erratum appears in OBSTET GYNECOL 2007 Jul;110(1):191].
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Minkoff H, Xian LS, Watts DH, Leighty R, Hershow R, Palefsky J, Tuomala R, Neu N, Zorrilla CD, Paul M, and Strickler H
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- 2006
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8. Immune parameter and morbidity in hard drug and human immunodeficiency virus-exposed but uninfected infants.
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Neu N, Leighty R, Adeniyi-Jones S, Diaz C, Handelsman E, Kaufman G, Paul ME, Rich K, Mofenson L, Pitt J, and Women and Infants Transmission Study
- Abstract
OBJECTIVE: To examine the association of maternal hard drug use (injection drugs, cocaine, and opiates) on lymphocyte subsets and clinical morbidity in uninfected infants who are born to human immunodeficiency virus-infected mothers who were enrolled in the Women and Infants Transmission Study (1990-2000). METHODS: Maternal hard drug use was identified by self-report and/or urine toxicology. Infant evaluations occurred at birth and at 1, 2, 4, 6, 9, 12, 18, and 24 months of age. RESULTS: A total of 401 (28%) of the 1436 uninfected infants were born to drug-using mothers. Maternal CD4 lymphocyte percentage and RNA at delivery were not significantly different between drug users and nonusers. Infants who were born to drug-using mothers had lower mean gestational age (37.8 vs 38.5 weeks) and birth weight (2.9 vs 3.1 kg). Infants with intrauterine drug exposure had lower CD4 lymphocyte percentage over the first 4 months of life after adjusting for covariates and higher natural killer lymphocyte percentage. When the analysis was stratified by time period of entry, the incidence of clinical events was not different between infants who were born to drug users versus nonusers. CONCLUSION: Maternal hard drug use is associated with immunologic changes in infants early in life, although these changes did not seem to be associated with increased risk of infections. [ABSTRACT FROM AUTHOR]
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- 2004
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9. RELATIVE CONTRIBUTION OF ORGANIC AND CLAY FRACTIONS TO CATIONEXCHANGE CAPACITY OF SANDY SOILS FROM SEVERAL SOIL GROUPS
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YUAN, T. L., GAMMON, NATHAN, and LEIGHTY, R. G.
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- 1967
10. RELATIVE CONTRIBUTION OF ORGANIC AND CLAY FRACTIONS TO CATION-EXCHANGE CAPACITY OF SANDY SOILS FROM SEVERAL SOIL GROUPS.
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Yuan, T. L., Gammon Jr., Nathan, and Leighty, R. G.
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- 1967
11. Terrain Navigation Concepts for Autonomous Vehicles
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ARMY ENGINEER TOPOGRAPHIC LABS FORT BELVOIR VA, Leighty,R D, ARMY ENGINEER TOPOGRAPHIC LABS FORT BELVOIR VA, and Leighty,R D
- Abstract
The Army's Artificial Intelligence/Robotics Demonstrator Program has resulted in expression of interest in a large number of potential autonomous vehicle applications within the Army Laboratory and TRADOC communities. In general this interest is based on the potential advantages of autonomous vehicle systems to improve efficiency of operations and to remove humans from hazardous environments on the battlefield. Examples of proposed autonomous vehicle applications are: intelligence collection, NBC reconnaissance, weapons platforms, transportation of supplies and materials, and medical evacuation. (Author)
- Published
- 1984
12. The AI (Artificial Intelligence) Environment at the U.S. Army Engineer Topographic Laboratories
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ARMY ENGINEER TOPOGRAPHIC LABS FORT BELVOIR VA RESEARCH INST, Leighty,R. D., ARMY ENGINEER TOPOGRAPHIC LABS FORT BELVOIR VA RESEARCH INST, and Leighty,R. D.
- Abstract
The U.S. Army Engineer Topographic Laboratories (USAETL) is responsible for Army research and development in the areas of mapping and terrain analysis. In general this involves methods, techniques, and systems for information processing related to the extraction, analysis, and presentation of terrain data. Typically, the data source is aerial imagery and the real-world information processing techniques for aerial imagery are very labor intensive. Previous research into automated techniques has not yielded results adequate to justify significant equipment developments necessary for future Army terrain information processing requirements. Thus, USAETL is making a significant commitment in AI with expectations for new and improved terrain information capabilities for the Army. This paper presents the rationale for the USAETL AI program, the objectives and approach of the Center for Artificial Intelligence (CAI), a description of the CAI AI facilities, and a brief description of the current CAI research program. (Author), This article is from 'Proceedings of the Army Conference on Application of Artificial Intelligence to Battlefield Information Management Held at White Oak, Maryland on April 20, 21, and 22, 1983,' AD-A139 685, p37-44.
- Published
- 1984
13. Hybrid Optical-Digital Pattern Recognition Apparatus and Method.
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DEPARTMENT OF THE ARMY WASHINGTON DC, Leighty,R D, Lukes,G E, DEPARTMENT OF THE ARMY WASHINGTON DC, Leighty,R D, and Lukes,G E
- Abstract
An improved apparatus and method of pattern recognition and of providing pattern recognition data, which possesses the advantages of optical power spectral analysis and digital image processing. An optical read-only memory means such as a photographic transparency is sampled at a plurality of sampling locations with a beam of coherent light. After passage through the transparency, the beam is directed either to a first channel including a transform lens and a wedge-ring detector or to a second channel including an imaging lens and a photodetector array. The improved pattern recognition data is the spatial frequency data provided by the wedge-ring detector and the spatial intensity data provided by the array detector. Hierarchal pattern recognition decisions are made using the two types of data during processing operations to provide improved pattern recognition results. (Author), Supersedes PAT-APPL-152 441-80.
- Published
- 1982
14. The AI Research Environment at the United States Army Engineer Topographic Laboratories
- Author
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ARMY ENGINEER TOPOGRAPHIC LABS FORT BELVOIR VA, Leighty,R D, ARMY ENGINEER TOPOGRAPHIC LABS FORT BELVOIR VA, and Leighty,R D
- Abstract
The U.S. Army Engineer Topographic Laboratories (USAETL) is responsible for Army research and development in the areas of mapping and terrain analysis. In general, this involves methods, techniques, and systems for information processing related to the extraction, analysis, and presentation of terrain data. Typically, the data source is aerial imagery and the real-world information processing techniques for aerial imagery are very labor-intensive. Previous research into automated techniques has not yielded results adequate to justify significant equipment developments necessary for future Army terrain information processing requirements. Thus, USAETL is making a significant commitment in AI with expectations for new and improved terrain information processing capabilities for the Army. This paper discusses the Artificial intelligence research environment at USAETL. This includes the rationale for the USAETL AI program, the objectives and approach of the Center for Artificial Intelligence (CAI), a description of the CAI AI facilities, and a brief description of the current CAI research program.
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- 1983
15. Coherent Optics in Mapping
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Balasubramanian, N., primary and Leighty, R. D., additional
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- 1975
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16. Applying optical pattern recognition techniques to aerial photographic analysis and stereographic mapping problems
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Leighty, R. D., primary
- Published
- 1976
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17. New Approach To Automated Optical/Digital Pattern Recognition
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Leighty, R. D., primary and Lukes, G. E., additional
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- 1979
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18. Hybrid Pattern Recognition Research At The U. S. Army Engineer Topographic Laboratories
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Leighty, R. D., primary and Lukes, G. E., additional
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- 1979
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19. Genetic variation in KSHV encoded microRNAs affects microRNA expression and is associated with multicentric Castleman’s disease risk
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Marshall Vickie, Ray Alex, Han Soo-Jin, Uldrick Thomas, Barsov Eugene, Quinones Octavio, Leighty Robert, Labo Nazzarena, Wyvill Kathy, Aleman Karen, Polizzotto Mark N, Little Richard F, Ott David, Yarchoan Robert, Renne Rolf, and Whitby Denise
- Subjects
Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 ,Infectious and parasitic diseases ,RC109-216 - Published
- 2012
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20. Pneumocystis carinii Pneumonia
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Mreiden, T., Rao, G., Philipp, F., Leighty, R. G., Wholey, M. H., Danowski, T. S., and Fisher, E. R.
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To the Editor.—Pneumocystis carinii pneumonia is characterized by progressive interstial inflammation caused by this protozoan. The diagnosis necessitates identification of the ameboid or encysted form in biopsy sections or impression smears of the lung, but the organism has been found in bronchial washings. We have encountered an instance in which biopsy specimens of a lower lobe bronchus and small portion of adjacent lung were negative for P carinii, but the organism was found in the sputum. Pneumonia disappeared during pentamidine isethionate therapy.Report of a Case.—A 47-year-old accounting clerk, alcoholic for ten years up to several months ago and emphysematous for two years, complained of anorexia, weight loss of 15.30 kg, weakness, and a nocturnal cough with yellowish sputum of two months' duration. He denied chills, fever, or night sweats. History was noncontributory. The patient smoked a pipe for eight years and ingested vitamin pills daily.He weighed
- Published
- 1976
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21. INSTRUMENTS AND METHODS: SNOW DENSITY PROFILING BY NUCLEAR MEANS
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Leighty, R
- Published
- 1966
22. CD4+ T Cell Help Selectively Enhances High-Avidity Tumor Antigen-Specific CD8+ T Cells.
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Zhu Z, Cuss SM, Singh V, Gurusamy D, Shoe JL, Leighty R, Bronte V, and Hurwitz AA
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- Animals, Antibody Affinity genetics, Antigens, Neoplasm immunology, Cell Line, Tumor, Dendritic Cells immunology, Epitopes, T-Lymphocyte immunology, Lymphocyte Activation immunology, Melanoma immunology, Mice, Mice, Inbred C57BL, Mice, Transgenic, Antibody Affinity immunology, CD4-Positive T-Lymphocytes immunology, CD8-Positive T-Lymphocytes immunology, Cytotoxicity, Immunologic immunology, Immune Tolerance immunology
- Abstract
Maintaining antitumor immunity remains a persistent impediment to cancer immunotherapy. We and others have previously reported that high-avidity CD8(+) T cells are more susceptible to tolerance induction in the tumor microenvironment. In the present study, we used a novel model where T cells derived from two independent TCR transgenic mouse lines recognize the same melanoma antigenic epitope but differ in their avidity. We tested whether providing CD4(+) T cell help would improve T cell responsiveness as a function of effector T cell avidity. Interestingly, delivery of CD4(+) T cell help during in vitro priming of CD8(+) T cells improved cytokine secretion and lytic capacity of high-avidity T cells, but not low-avidity T cells. Consistent with this observation, copriming with CD4(+) T cells improved antitumor immunity mediated by higher avidity, melanoma-specific CD8(+) T cells, but not T cells with similar specificity but lower avidity. Enhanced tumor immunity was associated with improved CD8(+) T cell expansion and reduced tolerization, and it was dependent on presentation of both CD4(+) and CD8(+) T cell epitopes by the same dendritic cell population. Our findings demonstrate that CD4(+) T cell help preferentially augments high-avidity CD8(+) T cells and provide important insight for understanding the requirements to elicit and maintain durable tumor immunity., (Copyright © 2015 by The American Association of Immunologists, Inc.)
- Published
- 2015
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23. Genome-wide DNA methylation patterns in LSH mutant reveals de-repression of repeat elements and redundant epigenetic silencing pathways.
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Yu W, McIntosh C, Lister R, Zhu I, Han Y, Ren J, Landsman D, Lee E, Briones V, Terashima M, Leighty R, Ecker JR, and Muegge K
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- Animals, Cell Nucleus genetics, Embryonic Stem Cells, Epigenesis, Genetic, Fibroblasts cytology, Fibroblasts metabolism, Gene Knockout Techniques, Histones metabolism, Lamin Type B metabolism, Mice, Molecular Sequence Data, Mutation, Regulatory Sequences, Nucleic Acid, Repetitive Sequences, Nucleic Acid, Cytosine metabolism, DNA metabolism, DNA Helicases genetics, DNA Methylation, Gene Expression Regulation, Developmental
- Abstract
Cytosine methylation is critical in mammalian development and plays a role in diverse biologic processes such as genomic imprinting, X chromosome inactivation, and silencing of repeat elements. Several factors regulate DNA methylation in early embryogenesis, but their precise role in the establishment of DNA methylation at a given site remains unclear. We have generated a comprehensive methylation map in fibroblasts derived from the murine DNA methylation mutant Hells(-/-) (helicase, lymphoid specific, also known as LSH). It has been previously shown that HELLS can influence de novo methylation of retroviral sequences and endogenous genes. Here, we describe that HELLS controls cytosine methylation in a nuclear compartment that is in part defined by lamin B1 attachment regions. Despite widespread loss of cytosine methylation at regulatory sequences, including promoter regions of protein-coding genes and noncoding RNA genes, overall relative transcript abundance levels in the absence of HELLS are similar to those in wild-type cells. A subset of promoter regions shows increases of the histone modification H3K27me3, suggesting redundancy of epigenetic silencing mechanisms. Furthermore, HELLS modulates CG methylation at all classes of repeat elements and is critical for repression of a subset of repeat elements. Overall, we provide a detailed analysis of gene expression changes in relation to DNA methylation alterations, which contributes to our understanding of the biological role of cytosine methylation., (© 2014 Yu et al.; Published by Cold Spring Harbor Laboratory Press.)
- Published
- 2014
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24. Endogenous retrovirus insertion in the KIT oncogene determines white and white spotting in domestic cats.
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David VA, Menotti-Raymond M, Wallace AC, Roelke M, Kehler J, Leighty R, Eizirik E, Hannah SS, Nelson G, Schäffer AA, Connelly CJ, O'Brien SJ, and Ryugo DK
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- Animals, Breeding, Cats, Genetic Linkage, Genetics, Population, Genotype, Hearing Loss pathology, Hearing Loss veterinary, Hematopoietic Stem Cells metabolism, Introns, Mast Cells metabolism, Pedigree, Phenotype, Proto-Oncogene Proteins c-kit metabolism, Retroelements genetics, Sequence Analysis, RNA, Terminal Repeat Sequences genetics, Endogenous Retroviruses genetics, Pigmentation genetics, Proto-Oncogene Proteins c-kit genetics
- Abstract
The Dominant White locus (W) in the domestic cat demonstrates pleiotropic effects exhibiting complete penetrance for absence of coat pigmentation and incomplete penetrance for deafness and iris hypopigmentation. We performed linkage analysis using a pedigree segregating White to identify KIT (Chr. B1) as the feline W locus. Segregation and sequence analysis of the KIT gene in two pedigrees (P1 and P2) revealed the remarkable retrotransposition and evolution of a feline endogenous retrovirus (FERV1) as responsible for two distinct phenotypes of the W locus, Dominant White, and white spotting. A full-length (7125 bp) FERV1 element is associated with white spotting, whereas a FERV1 long terminal repeat (LTR) is associated with all Dominant White individuals. For purposes of statistical analysis, the alternatives of wild-type sequence, FERV1 element, and LTR-only define a triallelic marker. Taking into account pedigree relationships, deafness is genetically linked and associated with this marker; estimated P values for association are in the range of 0.007 to 0.10. The retrotransposition interrupts a DNAase I hypersensitive site in KIT intron 1 that is highly conserved across mammals and was previously demonstrated to regulate temporal and tissue-specific expression of KIT in murine hematopoietic and melanocytic cells. A large-population genetic survey of cats (n = 270), representing 30 cat breeds, supports our findings and demonstrates statistical significance of the FERV1 LTR and full-length element with Dominant White/blue iris (P < 0.0001) and white spotting (P < 0.0001), respectively., (Copyright © 2014 David et al.)
- Published
- 2014
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25. An analysis of select emerging executive skills in perinatally HIV-1-infected children.
- Author
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Llorente AM, Brouwers P, Leighty R, Malee K, Smith R, Harris L, Serchuck LK, Blasini I, and Chase C
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- Child, Cross-Sectional Studies, Female, HIV Infections transmission, Humans, Infectious Disease Transmission, Vertical, Male, Risk Factors, Social Environment, United States, Cognition Disorders physiopathology, Executive Function physiology, HIV Infections physiopathology, HIV-1, Neuropsychological Tests
- Abstract
This study examined the effect of perinatal HIV-1 infection on emerging executive skills in children (n = 161) ages 8 to 12 years. HIV-positive (n = 76) and HIV-negative (n = 85) children were eligible to participate. The HIV-positive children included those who had experienced a CDC Class C event (greater severity, n = 22) and those who were HIV-positive but who had not experienced a CDC Class C event (less severity, n = 54). Measures of emerging executive functions completed by the children included subtests from the Developmental Neuropsychological Assessment (NEPSY), the Trail-Making Test-Part B, and a subtest from the Woodcock-Johnson Battery-Revised. Ratings of executive functions were obtained from caretakers using the Behavior Rating Inventory of Executive Functions. Generalized estimating equations methods, discriminate analyses, and global deficit score analyses were performed to determine whether differences emerged between the three clinical groups while using strict controls. The present results revealed significant group differences in unadjusted mean scores measuring executive functioning. However, such differences did not remain statistically significant when moderating variables were taken into consideration in the models. The apparent deficit in executive functioning for the HIV-positive children was found to be largely due to differential psychosocial and environmental factors rather than HIV disease and its severity, and in this cohort, the effects of HIV-1 infection on emerging executive functions appeared to be negligible when controlling for treatment and moderating psychosocial variables.
- Published
- 2014
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26. Effect of methomyl and oxamyl soil applications on early control of nematodes and insects.
- Author
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Desaeger JA, Rivera M, Leighty R, and Portillo H
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- Animals, Tylenchoidea growth & development, Carbamates pharmacology, Insecta drug effects, Methomyl pharmacology, Pest Control methods, Pesticides pharmacology, Soil parasitology, Tylenchoidea drug effects
- Abstract
Background: Methomyl is a widely used carbamate insecticide that has traditionally been applied as a foliar spray. More recently, methomyl has been labeled as a soil application via drip chemigation. Not much is known about the insecticidal and nematicidal potential of soil-applied methomyl. Methomyl soil applications were evaluated for their potential to control soil nematodes and foliar insect pests in a series of lab and greenhouse tests., Results: Methomyl showed rapid knockdown of Meloidogyne incognita (Kof. & White) Chitwood in aqueous assays, with EC50 and EC90 values that were similar to oxamyl and averaged 4.9 and 15.2 mg L(−1). In the greenhouse, soil applications of methomyl ranging from 0.56 to 4.0 kg ha(−1) provided significant M. incognita control similar to oxamyl during early growth (up to 25 days after planting) of pea and bean. Higher application rates and split applications improved nematode control, but also increased the risk of phytotoxicity. Methomyl soil applications were highly effective on several insects including Myzus persicae (Sulzer), Aphis gossypii (Glover), Frankliniella occidentalis Perg. and Spodoptera exigua (Hübner). Methomyl was about 5–9-fold more potent on M. persicae and A. gossypii when applied via soil drench as opposed to foliar spray. Potency on Bemisia tabaci Genn., S. exigua and Trichoplusia ni Hübner was about the same with the two application methods., Conclusion: Methomyl soil applications showed good potential for early control of various insect and nematode pests. Further testing is required to verify activity under field conditions.
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- 2011
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27. The tumour suppressor C/EBPδ inhibits FBXW7 expression and promotes mammary tumour metastasis.
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Balamurugan K, Wang JM, Tsai HH, Sharan S, Anver M, Leighty R, and Sterneck E
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- Animals, Cell Proliferation, Cell Survival, Cells, Cultured, F-Box-WD Repeat-Containing Protein 7, Glycolysis, Mammary Neoplasms, Animal pathology, Mammary Neoplasms, Animal physiopathology, Mice, Mice, Transgenic, Neoplasm Metastasis physiopathology, CCAAT-Enhancer-Binding Protein-delta metabolism, F-Box Proteins biosynthesis, Gene Expression Regulation, Hypoxia, Mammary Neoplasms, Animal secondary, Neoplasm Metastasis pathology, Ubiquitin-Protein Ligases biosynthesis
- Abstract
Inflammation and hypoxia are known to promote the metastatic progression of tumours. The CCAAT/enhancer-binding protein-δ (C/EBPδ, CEBPD) is an inflammatory response gene and candidate tumour suppressor, but its physiological role in tumourigenesis in vivo is unknown. Here, we demonstrate a tumour suppressor function of C/EBPδ using transgenic mice overexpressing the Neu/Her2/ERBB2 proto-oncogene in the mammary gland. Unexpectedly, this study also revealed that C/EBPδ is necessary for efficient tumour metastasis. We show that C/EBPδ is induced by hypoxia in tumours in vivo and in breast tumour cells in vitro, and that C/EBPδ-deficient cells exhibit reduced glycolytic metabolism and cell viability under hypoxia. C/EBPδ supports CXCR4 expression. On the other hand, C/EBPδ directly inhibits expression of the tumour suppressor F-box and WD repeat-domain containing 7 gene (FBXW7, FBW7, AGO, Cdc4), encoding an F-box protein that promotes degradation of the mammalian target of rapamycin (mTOR). Consequently, C/EBPδ enhances mTOR/AKT/S6K1 signalling and augments translation and activity of hypoxia-inducible factor-1α (HIF-1α), which is necessary for hypoxia adaptation. This work provides new insight into the mechanisms by which metastasis-promoting signals are induced specifically under hypoxia.
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- 2010
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28. Kidney-targeted Birt-Hogg-Dube gene inactivation in a mouse model: Erk1/2 and Akt-mTOR activation, cell hyperproliferation, and polycystic kidneys.
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Baba M, Furihata M, Hong SB, Tessarollo L, Haines DC, Southon E, Patel V, Igarashi P, Alvord WG, Leighty R, Yao M, Bernardo M, Ileva L, Choyke P, Warren MB, Zbar B, Linehan WM, and Schmidt LS
- Subjects
- Animals, Antibiotics, Antineoplastic pharmacology, Blotting, Southern, Disease Models, Animal, Estrone genetics, Fluorescent Antibody Technique, Genotype, Germ-Line Mutation, Immunoblotting, Immunohistochemistry, Kaplan-Meier Estimate, Kidney drug effects, Kidney Neoplasms metabolism, Kidney Neoplasms pathology, Mice, Mice, Knockout, Mitogen-Activated Protein Kinase 1 drug effects, Mitogen-Activated Protein Kinase 3 drug effects, Polycystic Kidney Diseases complications, Polycystic Kidney Diseases metabolism, Polycystic Kidney Diseases pathology, Protein Kinases drug effects, Random Allocation, Reverse Transcriptase Polymerase Chain Reaction, Signal Transduction drug effects, Sirolimus pharmacology, Syndrome, TOR Serine-Threonine Kinases, Cell Proliferation drug effects, Gene Silencing, Kidney metabolism, Kidney pathology, Kidney Neoplasms genetics, Mitogen-Activated Protein Kinase 1 metabolism, Mitogen-Activated Protein Kinase 3 metabolism, Polycystic Kidney Diseases genetics, Protein Kinases metabolism, Proto-Oncogene Proteins genetics, Tumor Suppressor Proteins genetics
- Abstract
Background: Patients with Birt-Hogg-Dubé (BHD) syndrome harbor germline mutations in the BHD tumor suppressor gene that are associated with an increased risk for kidney cancer. BHD encodes folliculin, a protein that may interact with the energy- and nutrient-sensing 5'-AMP-activated protein kinase-mammalian target of rapamycin (AMPK-mTOR) signaling pathways., Methods: We used recombineering methods to generate mice with a conditional BHD allele and introduced the cadherin 16 (KSP)-Cre transgene to target BHD inactivation to the kidney. Kidney cell proliferation was measured by BrdU incorporation and phospho-histone H3 staining. Kidney weight data were analyzed with Wilcoxon's rank-sum, Student's t, and Welch's t tests. Hematoxylin and eosin staining and immunoblot analysis and immunohistochemistry of cell cycle and signaling proteins were performed on mouse kidney cells and tissues. BHD knockout mice and kidney cells isolated from BHD knockout and control mice were treated with the mTOR inhibitor rapamycin. Mouse survival was evaluated by Kaplan-Meier analyses. All statistical tests were two-sided., Results: BHD knockout mice developed enlarged polycystic kidneys and died from renal failure by 3 weeks of age. Targeted BHD knockout led to the activation of Raf-extracellular signal-regulated protein kinase (Erk)1/2 and Akt-mTOR pathways in the kidneys and increased expression of cell cycle proteins and cell proliferation. Rapamycin-treated BHD knockout mice had smaller kidneys than buffer-treated BHD knockout mice had (n = 4-6 mice per group, relative kidney/body weight ratios, mean = 4.64% vs 12.2%, difference = 7.6%, 95% confidence interval = 5.2% to 10.0%; P < .001) and longer median survival time (n = 4-5 mice per group, 41.5 vs 23 days; P = .0065 )., Conclusions: Homozygous loss of BHD may initiate renal tumorigenesis in the mouse. The conditional BHD knockout mouse may be a useful research model for dissecting multistep kidney carcinogenesis, and rapamycin may be considered as a potential treatment for Birt-Hogg-Dubé syndrome.
- Published
- 2008
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29. Effects of perinatal HIV infection and associated risk factors on cognitive development among young children.
- Author
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Smith R, Malee K, Leighty R, Brouwers P, Mellins C, Hittelman J, Chase C, and Blasini I
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- Adolescent, Adult, Child, Child, Preschool, Female, HIV Infections complications, HIV Infections congenital, HIV Infections drug therapy, HIV Seropositivity, Humans, Infant, Newborn, Infectious Disease Transmission, Vertical, Intelligence, Longitudinal Studies, Pregnancy, Pregnancy Complications, Infectious drug therapy, Psychomotor Performance, Risk Factors, Socioeconomic Factors, Child Development, Cognition, HIV Infections psychology
- Abstract
Objective: We examined the effect of HIV, in combination with other important health and social factors, on the development of cognitive abilities of children perinatally exposed to HIV., Methods: Serial cognitive assessments were performed for 117 children who were infected vertically and 422 children who were exposed to but not infected with HIV, in a multicenter, natural history, longitudinal study. Repeated-measures analyses were used to evaluate the neurocognitive development of children between the ages of 3 and 7 years, as measured by the McCarthy Scales of Children's Abilities (MSCA)., Results: Children with HIV infection and class C status scored significantly lower in all domains of cognitive development, across all time points, than did those who were HIV infected without an AIDS-defining illness and those who were HIV exposed but not infected. There were no significant differences between the 2 latter groups in General Cognitive Index or specific domain scores. Rates of change in cognitive development were comparable (parallel) among all 3 groups over a period of 4 years. Factors that were associated consistently and significantly with lower mean scores were HIV status, number of times an examination had been completed previously, primary language, maternal education, and gender. No factors were related to rate of change of any mean domain score., Conclusions: An early AIDS-defining illness increased the risk of chronic static encephalopathy during the preschool and early school age years. Children with HIV infection but no class C event performed as well as noninfected children in measures of general cognitive ability. No significantly different profiles of strengths and weaknesses for verbal, perceptual-performance, quantitative, or memory functioning were observed among children with or without HIV infection. A number of factors were found to have significant effects on the mean scores of children in all 3 groups; however, they were not related to the rate at which learning occurred.
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- 2006
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30. Lifelong immunization with human beta-amyloid (1-42) protects Alzheimer's transgenic mice against cognitive impairment throughout aging.
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Jensen MT, Mottin MD, Cracchiolo JR, Leighty RE, and Arendash GW
- Subjects
- Animals, Anxiety genetics, Anxiety psychology, Cognition Disorders immunology, Hand Strength physiology, Humans, Image Processing, Computer-Assisted, Immunization Schedule, Maze Learning physiology, Memory physiology, Mice, Mice, Inbred C57BL, Mice, Transgenic, Motor Activity physiology, Oligopeptides genetics, Oligopeptides metabolism, Postural Balance physiology, Psychomotor Performance physiology, Aging psychology, Alzheimer Disease genetics, Alzheimer Vaccines immunology, Amyloid beta-Peptides immunology, Cognition Disorders genetics, Cognition Disorders prevention & control, Peptide Fragments immunology, Vaccination
- Abstract
Although both active and passive beta-amyloid (Abeta) immunotherapy have been shown to protect against or lessen cognitive impairment in various Alzheimer's transgenic mouse lines, these studies have focused on a single task and involved standard statistical analysis. Because Alzheimer's disease impacts multiple cognitive domains, the current study employed an extensive behavioral battery and multimetric analysis therein to determine the impact of Abeta immunization given throughout most of adult life (from 2-16 1/2 months of age) to APP+PS1 transgenic mice. At both adult (4 1/2-6 month) and aged (15-16 1/2 month) test points, the same 6-week behavioral battery was administered. Results indicate that Abeta immunotherapy partially or completely protected APP+PS1 mice at both test points from otherwise impaired performance in a variety of tasks spanning multiple cognitive domains (reference learning/memory, working memory, search/recognition). At both adult and aged test points, the cognitive benefits of Abeta immunotherapy were evident even when behavioral measures were analyzed collectively (as "overall" performance) through discriminant function analysis. Since behavioral protection at the 15-16 1/2 month test point occurred without a decrease in (or correlation to) Abeta deposition, the mechanism of Abeta immunotherapy's action most likely involves neutralization/removal of small Abeta oligomers from the brain. However, in factor analysis performed at this aged test point, brain Abeta deposition measures loaded heavily with key cognitive measures. Collectively, our results suggest that the entire process of Abeta deposition deleteriously impacts cognitive performance and that Abeta-based preventative strategies can provide long-term cognitive benefits extending well into older age.
- Published
- 2005
- Full Text
- View/download PDF
31. Auditory evoked potentials, clinical vs. research applications.
- Author
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Boutros N, Nasrallah H, Leighty R, Torello M, Tueting P, and Olson S
- Subjects
- Adult, Female, Humans, Male, Research, Schizophrenia physiopathology, Schizophrenia, Paranoid diagnosis, Schizophrenia, Paranoid physiopathology, Evoked Potentials, Auditory, Schizophrenia diagnosis
- Abstract
Evidence of abnormal auditory evoked potentials (EPs) in patients suffering from schizophrenia has been accumulating. In spite of the magnitude of the EPs in schizophrenia literature, EPs have not been found to be clinically useful thus far. In this study we attempted to replicate the findings in a large sample of schizophrenia patients, and describe how auditory EPs may be used as supplemental tests in the differential diagnostic process. Five subject groups were formed; paranoid (PAR) and disorganized/undifferentiated (disorg/undiff) schizophrenics, schizoaffective (SA), bipolar, and a normal control group. All patients were stable on medications. Subjects underwent one EP recording session. Classification and regression trees (CART) based on EP amplitudes were used to classify subjects into subgroups. The optimal Bayes classification rule that minimizes the expected misclassification cost was then constructed for various misclassification cost functions. In a standard 'Odd Ball' paradigm the N100 amplitudes were significantly decreased in the disorg/undiff group than in the bipolar or normal subjects. The P200 amplitude was smaller in the PAR, disorg/undiff and the SA groups than in the normal controls. Both the disorg/undiff and the PAR groups had significantly lower P300 amplitudes than the normal controls. Classification rules used to classify subjects into normal or ill were sensitive to the relative cost of misclassifying a subject, as well as the prior clinical probability that this subject was ill. Our data largely agree with the existing literature showing abnormally decreased N100, P200, and P300 amplitudes in schizophrenic patients, particularly the disorg/undiff patients. We conclude that whether EP measures are clinically useful depends on the clinical situation. In particular, the prior probability of the diagnosis in question being present and the cost of misclassifying the patient are critical.
- Published
- 1997
- Full Text
- View/download PDF
32. Wear patterns on retrieved polyethylene tibial inserts and their relationship to technical considerations during total knee arthroplasty.
- Author
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Wasielewski RC, Galante JO, Leighty RM, Natarajan RN, and Rosenberg AG
- Subjects
- Adult, Aged, Biomechanical Phenomena, Humans, Knee Joint diagnostic imaging, Logistic Models, Middle Aged, Prosthesis Design statistics & numerical data, Radiography, Reoperation, Surface Properties, Tibia, Knee Prosthesis statistics & numerical data, Polyethylenes
- Abstract
Fifty-five unconstrained polyethylene tibial inserts were retrieved at revision total knee arthroplasty and examined for evidence of wear after a mean implantation time of 34.2 months (2.5-80 months). Twenty inserts were ultra-high molecular weight polyethylene (UHMWPE) and 35 were carbon-reinforced polyethylene. Topographic maps of the articular and metal-backed surfaces of each component were constructed to characterize the extent and location of polyethylene degradation, identified visually by mode. In 32 of the retrieved inserts, pre- and postarthroplasty or prerevision radiographs were analyzed for component positioning, sizing, and extremity alignment. These factors then were compared with the patterns and severity of polyethylene wear on the inserts to establish correlations. Severe generalized articular wear was seen in inserts with third body wear from patellar metal-backed failure and cement debris. Severe localized delamination wear was seen in inserts with rotational-subluxation patterns of wear (p = 0.05). The external rotation subluxation wear pattern was strongly associated with knees that had lateral subluxation of the patella (p = 0.0002). Articular wear and cold flow into screw holes tended to be greater in the tightest prearthroplasty compartment (medial in the varus knee [p = 0.0157]; lateral in the valgus knees [p = 0.0226]). Fourteen of 16 knees with a preoperative varus deformities--even when corrected to a normal postarthroplasty anatomic axis--still had greater medial compartment articular wear (p = 0.001). Twelve of these knees did not have a medial release at the time of initial arthroplasty. Preoperative varus also was found to be related to the occurrence of posteromedial cold flow of polyethylene into tibial tray screw holes (p = 0.007). Increasing tibial insert posterior slope was associated with increasingly posterior articular wear track location (p = 0.03). This study indicates that unconstrained tibial component wear patterns and severity may be associated with clinical and mechanical factors under the surgeon's control, including component size and position, and knee alignment and ligament balance.
- Published
- 1994
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