Activation of lysosomal function during dendritic cell maturation   总被引：1，自引：0，他引：1  

Trombetta ES  Ebersold M  Garrett W  Pypaert M  Mellman I 《Science (New York, N.Y.)》2003,299(5611):1400-1403

In response to a variety of stimuli, dendritic cells (DCs) transform from immature cells specialized for antigen capture into mature cells specialized for T cell stimulation. During maturation, the DCs acquire an enhanced capacity to form and accumulate peptide-MHC (major histocompatibility complex) class II complexes. Here we show that a key mechanism responsible for this alteration was the generalized activation of lysosomal function. In immature DCs, internalized antigens were slowly degraded and inefficiently used for peptide loading. Maturation induced activation of the vacuolar proton pump that enhanced lysosomal acidification and antigen proteolysis, facilitating efficient formation of peptide-MHC class II complexes. Lysosomal function in DCs thus appears to be specialized for the developmentally regulated processing of internalized antigens.  相似文献   

Spatial pattern formation in an insect host-parasitoid system     

JL Maron  S Harrison 《Science (New York, N.Y.)》1997,278(5343):1619-1621

Spatial models in ecology predict that populations may form patchy distributions within continuous habitats, through strong predator-prey or host-parasitoid interactions combined with limited dispersal. Empirical support of these models is provided. Parasitoids emanating from a population outbreak of tussock moths (Orgyia vetusta) suppressed the growth of nearby experimental populations of the moth, while experimental populations farther away were able to grow. This result explains the observed localized nature of tussock moth outbreaks and illustrates how population distributions can be regulated by dynamic spatial processes.  相似文献   

Functional diversity vs. monotony: the effect of a multiforage diet as opposed to a single forage diet on animal intake,performance, welfare,and urinary nitrogen excretion     

Konagh Garrett  Matt R Beck  Cameron J Marshall  Anita E Fleming  Chris M Logan  Thomas M R Maxwell  Andrew W Greer  Pablo Gregorini 《Journal of animal science》2021,99(5)

The objective of this study was to determine the effect of offering animals a multiforage choice (MF) of fresh herbages on dry matter intake (DMI), live weight gain, and animal welfare, in comparison with a monotonous diet of ryegrass (Lolium perenne L.). Twenty ram lambs (30.5 ± 0.9 kg initial live weight; mean ± SEM), were randomly allocated to either a diet consisting of diverse MF choice or a single forage ryegrass (SF) diet (n = 10 per treatment) for 35 d. Both diets were fed ad libitum; however, the MF diet was composed of set dry matter ratios of 24% chicory (Cichorium intybus L.), 30% lucerne (Medicago sativa L.), 25% plantain (Plantago lanceolata L.), and 21% ryegrass. The DMI of the MF lambs was 48% greater (P < 0.01) and the within animal day-to-day coefficient of variation (CV) of intake was 26% lower (P < 0.01) than the SF lambs. The average daily gain (ADG) of lambs offered the MF diet was 92% greater (P < 0.01) than the lambs offered the SF diet. The within-animal day-to-day CV of intake was negatively related to ADG (r = −0.59; P < 0.01). The MF lamb’s urinary N concentration was 30% lower (P < 0.01) than that of the SF lambs. The SF lambs spent more time (P < 0.05) exhibiting stereotypic behaviors in the afternoon and spent more time observing other animals than the MF. Overall, allocating an MF choice of fresh herbages as opposed to a single forage diet of ryegrass increases DMI and thereby animal performance, while potentially reducing urinary N excretion.  相似文献   

Clinical ophthalmological diagnostic description of 10 healthy sugar gliders (Petaurus breviceps) and prevalence of ocular‐related presentations in a larger hospital population     

Garrett A. Fraess  Miranda J. Sadar  Joshua B. Daniels  Leslie C. Sharkey  Michala de Linde Henriksen 《Veterinary ophthalmology》2021,24(1):80-92

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Fluoroquinolone exposure in utero did not affect articular cartilage of resulting foals     

Robyn E. Ellerbrock  Igor F. Canisso  Ryan J. Larsen  Katherine S. Garrett  Matthew C. Stewart  Kalyn K. Herzog  Mariana E. Kersh  Sara G. Moshage  Giorgia Podico  Fabio S. Lima  Bronwen A. Childs 《Equine veterinary journal》2021,53(2):385-396

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Earth-Based Observations of the Galileo Probe Entry Site     

G Orton  JL Ortiz  K Baines  G Bjoraker  U Carsenty  F Colas  A Dayal  D Deming  P Drossart  E Frappa  J Friedson  J Goguen  W Golisch  D Griep  C Hernandez  W Hoffmann  D Jennings  C Kaminski  J Kuhn  P Laques  S Limaye  H Lin  J Lecacheux  T Martin  G McCabe  T Momary  D Parker  R Puetter  M Ressler  G Reyes  P Sada  J Spencer  J Spitale  S Stewart  J Varsik  J Warell  W Wild  P Yanamandra-Fisher  G Fazio  J Hora  L Deutsch 《Science (New York, N.Y.)》1996,272(5263):839-840

Earth-based observations of Jupiter indicate that the Galileo probe probably entered Jupiter's atmosphere just inside a region that has less cloud cover and drier conditions than more than 99 percent of the rest of the planet. The visual appearance of the clouds at the site was generally dark at longer wavelengths. The tropospheric and stratospheric temperature fields have a strong longitudinal wave structure that is expected to manifest itself in the vertical temperature profile.  相似文献   

Managing for Fine-Scale Differences in Inoculum Load: Seeding Patterns to Minimize Wheat Yield Loss to Take-all   总被引：1，自引：0，他引：1  

Garrett  K. A.  Kabbage  M.  Bockus  W. W. 《Precision Agriculture》2004,5(3):291-301

For pathogens with highly localized inoculum, controlled positioning of susceptible plants can be used to delay exposure to the pathogen. For example, when wheat is direct-drilled in fields where wheat was infected by Gaeumannomyces graminis var. tritici (Ggt) in the previous season, the remaining rows of wheat crowns serve as an inoculum source for the new wheat planting. In order to determine how different seeding patterns of wheat might affect yield loss to Ggt, we constructed a mathematical model in three stages. First, we calculated the probability density function for the distance between a new seed and the nearest old row of crowns for two main planting scenarios: parallel to the previous year's rows or at an angle to them. Second, we used estimates from Kabbage and Bockus [Kabbage, M. and Bockus, W. W. 2002. Plant Disease 86, 298–303] of the yield loss to Ggt as a function of the distance between wheat seed and inoculum source. Third, we combined these two models to estimate the average yield loss for different planting patterns. We estimated that planting parallel to and between the previous year's rows would cut yield loss almost in half for a typical row spacing compared to angled planting, provided there was not an important offset, or bias, in the position of the parallel planting. Planter wobble was relatively unimportant if there was no systematic bias in position.  相似文献   

Femtosecond resolution of soft mode dynamics in structural phase transitions     

Dougherty TP  Wiederrecht GP  Nelson KA  Garrett MH  Jensen HP  Warde C 《Science (New York, N.Y.)》1992,258(5083):770-774

The microscopic pathway along which ions or molecules in a crystal move during a structural phase transition can often be described in terms of a collective vibrational mode of the lattice. In many cases, this mode, called a "soft" phonon mode because of its characteristically low frequency near the phase transition temperature, is difficult to characterize through conventional frequency-domain spectroscopies such as light or neutron scattering. A femtosecond time-domain analog of light-scattering spectroscopy called impulsive stimulated Raman scattering (ISRS) has been used to examine the soft modes of two perovskite ferroelectric crystals. The low-frequency lattice dynamics of KNbO(3) and BaTiO(3) are clarified in a manner that permits critical evaluation of microscopic models for their ferroelectric transitions. The results illustrate the advantages of ISRS over conventional Raman spectroscopy of low-frequency, heavily damped soft modes.  相似文献   

Nutrition change strategies: the new frontier     

McLachlan M  Garrett J 《Public health nutrition》2008,11(10):1063-1075

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Characterization of storage proteins in wild (Glycine soja) and cultivated (Glycine max) soybean seeds using proteomic analysis   总被引：1，自引：0，他引：1  

Natarajan SS  Xu C  Bae H  Caperna TJ  Garrett WM 《Journal of agricultural and food chemistry》2006,54(8):3114-3120

A combined proteomic approach was applied for the separation, identification, and comparison of two major storage proteins, beta-conglycinin and glycinin, in wild (Glycine soja) and cultivated (Glycine max) soybean seeds. Two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) with three different immobilized pH gradient (IPG) strips was an effective method to separate a large number of abundant and less-abundant storage proteins. Most of the subunits of beta-conglycinin were well-separated in the pH range 3.0-10.0, while acidic and basic glycinin polypeptides were well-separated in pH ranges 4.0-7.0 and 6.0-11.0, respectively. Although the overall distribution pattern of the protein spots was similar in both genotypes using pH 3.0-10.0, variations in number and intensity of protein spots were better resolved using a combination of pH 4.0-7.0 and pH 6.0-11.0. The total number of storage protein spots detected in wild and cultivated genotypes was approximately 44 and 34, respectively. This is the first study reporting the comparison of protein profiles of wild and cultivated genotypes of soybean seeds using proteomic tools.  相似文献