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181.
Patrik Pipkorn Candy Costantini Curt Reynolds Michael Wall Margaret Drake Alvin Sanico David Proud Alkis Togias 《Annals of allergy, asthma & immunology》2008,101(1):82-89
BACKGROUND: Olopatadine, an antihistamine used in allergic conjunctivitis, is under development as a nasal preparation for the treatment of allergic rhinitis. OBJECTIVES: To evaluate the efficacy of olopatadine in suppressing symptoms and biomarkers of the immediate reaction induced by nasal allergen provocation and to compare olopatadine with azelastine in the same model. METHODS: The study was approved by the Johns Hopkins University institutional review board, and all subjects gave written consent. We studied 20 asymptomatic subjects with seasonal allergic rhinitis. The study had 2 randomized, double-blind, placebo-controlled, crossover phases that evaluated 2 concentrations of olopatadine, 0.1% and 0.2%. In a third exploratory phase, olopatadine, 0.1%, was compared with topical azelastine, 0.1%, in a patient-masked design. Efficacy variables were the allergen-induced sneezes, other clinical symptoms, and the levels of histamine, tryptase, albumin, lysozyme, and cysteinyl-leukotrienes (third study only) in nasal lavage fluids. RESULTS: Both concentrations of olopatadine produced significant inhibition of all nasal symptoms, compared with placebo. Olopatadine, 0.1%, inhibited lysozyme levels, but olopatadine, 0.2%, inhibited histamine, albumin, and lysozyme. The effects of olopatadine, 0.1%, were comparable to those of azelastine, 0.1%. CONCLUSIONS: Olopatadine, at 0.1% and 0.2% concentrations, was effective in suppressing allergen-induced nasal symptoms. At 0.2%, olopatadine provided evidence suggestive of inhibition of mast cell degranulation. 相似文献
182.
Modulation of Event-Related Potentials by Word Repetition: The Effects of Inter-Item Lag 总被引:5,自引:0,他引:5
The modulation of event-related potentials by word repetition was investigated in two experiments. In both experiments, subjects responded to occasional nonwords interspersed among a series of words. A proportion of the words were repetitions of previously presented items. Words were repeated after 0 or 6 intervening items in Experiment 1 and after 6 or 19 items in Experiment 2. Event-related potentials to repeated words were characterised by a sustained, widespread positive-going shift with an onset of approximately 300 ms. This effect did not vary significantly as a function of lag in either experiment. When words were repeated immediately, this repetition-evoked positive shift was preceded by a transient negative deflection (onset ca. 200 ms) which was absent in event-related potentials to words repeated at longer lags. These results suggest that the modulation of event-related potentials by word repetition is influenced by at least two processes. One of these processes acts relatively early during the processing of a repeated word, but subsides rapidly as inter-item lag between first and second presentations increases. The second process occurs later in time, but is considerably more robust over variations in inter-item lag. 相似文献
183.
Brian T. Butcher Carol E. ONeil Margaret A. Reed John E. Salvaggio Hans Weill 《The Journal of allergy and clinical immunology》1982,70(4):231-235
Toluene diisocyanate (TDI) sensitivity accompanied by nonspecific bronchial hyperresponsiveness occurs in approximately 5% of occupationally exposed workers. We report the case of a 32-yr-old worker followed longitudinally after removal from isocyanate exposure. TDI reactivity was lost 11 mo after removal from exposure and nonspecific bronchial hyperresponsiveness resolved after 17 mo. Bronchial reactivity to radishes (Raphanus sativus), which developed concurrently with TDI reactivity, was lost 2 yr later. Immunopharmacologic results show that the worker's initial decreased ability of lymphocytes to produce cyclic AMP returned to near normal after 2 yr. IgE antibodies to a human serum albumin tolyl monoisocyanate conjugate were still present at this time. 相似文献
184.
The cytotoxic and mutagenic effects of various monofunctionaland bifunctional alkylating agents have been assessed in V79Chinese hamster cells that express either the entire O6-alkylguanine(O6AG) and alkylphosphotriester alkyltransferase (ATase) gene(clone 8 cells) or a truncated form that codes only for O6AGATase activity (clone SB cells). Protection ratios, as determinedby D37 values, were greater for clone 8 cells than for SB cells.Significant protection against the mutagenic effects of N-methyl-N-nitrosoureaand ethylmethanesulphonate at the hypoxanthine phosphoribosyltransferase(HPRT) locus was observed in clone 8 and SB cells. Streptozotocinand the haloethyl nitrosoureas, chlorozotocin and bis-chloroethylnitrosoureawere less efficient in inducing HPRT-deficient mutants and asmaller degree of protection was afforded by the transfectedgenes. This is possibly due to the propensity of these compoundsto induce multi-locus deletions. Southern analysis of DNA fromclone 8 and SB cells indicated the presence of multiple copiesof the plasmid integrated into clone 8 cells but few copiesin clone SB cells. The copy number did not change but ATaselevels fell when cells were grown in the absence of G418.
2Present address: Corporate Biosciences Laboratory, ICI plc,The Heath, Runcorn, Cheshire, UK 相似文献
185.
Ursula G. Froster-Iskenius Cynthia Curry Margaret Philp Judith G. Hall John M. Opitz James F. Reynolds 《American journal of medical genetics. Part A》1988,30(3):763-769
We report on a patient with a lethal multiple pterygium syndrome who also had an unusual, bandlike web across one axilla and partial intestinal atresia. Umbilical cord wrapping with subsequent vascular compromise appears to be the most likely pathogenetic mechanism for the additional anomalies. 相似文献
186.
Summary. With the introduction of cutting-grown Petunia x hybrida plants on the European market, a new potyvirus which showed no serological reaction with antisera against any other potyviruses
infecting petunias was discovered. Infected leaves contained flexuous rod-shaped virus particles of 750 – 800 nm in length
and inclusion bodies (pinwheel structures) typical for potyviruses in ultrathin leaf sections. The purified coat protein with
a Mr of approximately 36 kDa could be detected in Western immunoblots with a specific antibody to the coat protein of the petunia-infecting
virus. The 3′ end of the viral genome encompassing the 3′ non-coding region, the coat protein gene, and part of the NIb gene
was amplified from infected leaf material by IC/PCR using degenerate and specific primers. Sequences of PCR-generated cDNA
clones were compared to other known sequences of potyviruses. Maximum homology of 56% was found in the 3′ non-coding region
between the petunia isolate and other potyviruses. A maximum homology of 69% was found between the amino acid sequence of
the coat protein of the petunia isolate and corresponding sequences of other potyviruses. These data indicate that the petunia-infecting
virus is a previously undescribed potyvirus and the name petunia flower mottle virus (PetFMV) is suggested.
Accepted November 5, 1997 Received July 25, 1997 相似文献
187.
Anthony L. Mansell Margaret H. Collins Eddie Johnson Joan Gil 《Anatomical record (Hoboken, N.J. : 2007)》1995,241(1):99-104
Background: A previous study of piglet lung growth (Mansell et. al. 1989. J. Appl. Physiol., 67:1422–1427) showed transient stiffness to changes in shape and volume immediately after birth. Later, elastic recoil was found to increase as the lung grew in weight and volume. The present study uses morphometry to test possible structural correlates of these two mechanical changes. Methods: Piglet lungs were fixed near full inflation via the airways during the immediate newborn period (6–12 hours, n=3), at 3–5 days (n=6), 25–30 days (n=5), and 80–85 days (n=3). Morphometry comprised arithmetic and harmonic mean thicknesses of alveolar septae and average mean surface curvature. Measurements of curvature and airspace volume were combined to differentiate alveolar expansion from septal proliferation as mechanisms for volumetric growth. Results: The unique mechanical behavior of the newborn lungs was associated with relatively thick alveolar septae. Marked thinning of the septae and resolution of the stiffness to shape and volume change had occurred by 3–5 days. An increase in elastic recoil during the first postnatal month was found to be associated with simple airspace expansion. The second and third months were characterized by septal proliferation and increase in arithmetic mean septal thickness but elastic recoil did not increase further. Harmonic mean septal thickness and airspace volume per gram of lung tissue did not change over the course of the study. Conclusions: 1) A relative stiffness to shape and volume change in freshly newborn piglet lung is associated with relatively thick alveolar septal walls; 2) postnatal development of piglet lung parenchyma involves septal lengthening and thinning followed by septal proliferation; 3) the initial phase of septal lengthening, rather than the later phase of septal proliferation, is associated with increase in parenchymal recoil. © 1995 Wiley-Liss, Inc. 相似文献
188.
Gail Ironson George Solomon Dean Cruess Julie Barroso Margaret Stivers 《Clinical psychology & psychotherapy》1995,2(4):249-266
Only a few studies of long-term survivors of AIDS (those who survive more than twice the median expected time) have been done but these reveal a constellation of psychological characteristics including, but not limited to, those with active coping, social support, life involvement, ability to communicate, and active collaboration with one's doctor. Another related literature consists of longitudinal studies following people infected with the HIV virus to determine whether psychological characteristics are related to disease progression. These studies have focused on coping, depression, negative expectancies and social support as predictors. This article reviews and integrates the two bodies of literature combining the variables identified into four psychosocial strategies related to longer survival with HIV/AIDS: following healthy self care; maintaining connectedness; having a sense of meaning or purpose in life; and maintaining perspective. Affect, beliefs, and behaviour are all seen as important. Biological variables, SES and psychological resources that the person brings to the situation and external stresses are seen as important variables to consider in prediction studies. The pathways through which these four strategies may operate (both psychological and biological) to impact on health are discussed. Psychological pathways include distress and behavioural disengagement, while biological pathways involve the sympathetic nervous system, neuroendocrine and immune mediation. Finally suggestions for future research are given. 相似文献
189.
Juliana Chen Solne Bertrand Olivier Galy David Raubenheimer Margaret Allman-Farinelli Corinne Caillaud 《Nutrients》2021,13(5)
The food environment in New Caledonia is undergoing a transition, with movement away from traditional diets towards processed and discretionary foods and beverages. This study aimed to develop an up-to-date food composition database that could be used to analyze food and nutritional intake data of New Caledonian children and adults. Development of this database occurred in three phases: Phase 1, updating and expanding the number of food items to represent current food supply; Phase 2, refining the database items and naming and assigning portion size images for food items; Phase 3, ensuring comprehensive nutrient values for all foods, including saturated fat and total sugar. The final New Caledonian database comprised a total of 972 food items, with 40 associated food categories and 25 nutrient values and 615 items with portion size images. To improve the searchability of the database, the names of 593 food items were shortened and synonyms or alternate spelling were included for 462 foods. Once integrated into a mobile app-based multiple-pass 24-h recall tool, named iRecall.24, this country-specific food composition database would support the assessment of food and nutritional intakes of families in New Caledonia, in a cross-sectional and longitudinal manner, and with translational opportunities for use across the wider Pacific region. 相似文献
190.
Modelling and simulation methods can play an important role in guiding public health responses to infectious diseases and emerging health threats by projecting the plausible outcomes of decisions and interventions. The 2003 SARS epidemic marked a new chapter in disease modelling in Canada as it triggered a national discussion on the utility and uptake of modelling research in local and pandemic outbreaks. However, integration and application of model-based outcomes in public health requires knowledge translation and contextualization. We reviewed the history and performance of Pan-InfORM (Pandemic Influenza Outbreak Research Modelling), which created a national infrastructure in Canada with a mandate to develop innovative knowledge translation methodologies to inform policy makers through modelling frameworks that bridge the gaps between theory, policy, and practice. This review demonstrates the importance of a collaborative infrastructure as a “Community of Practice” to guide public health responses, especially in the context of emerging diseases with substantial uncertainty, such as the COVID-19 pandemic. Dedicated resources to modelling and knowledge translation activities can help create synergistic strategies at the global scale and optimize public health responses to protect at-risk populations and quell socioeconomic and health burden. 相似文献