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81.
Since its invasion of North America in 2000, the soybean aphid, Aphis glycines Matsumura (Homoptera: Aphididae) has notably changed the arthropod community of the soybean agroecosystem. The objectives of this study were to characterize the foliar predatory fauna associated with A. glycines in commercial soybean fields in Québec, Canada, and to evaluate the suitability of A. glycines as prey for three coccinellid species: Harmonia axyridis Pallas, Propylea quatuordecimpunctata L. and Coleomegilla maculata lengi Timberlake (Coleoptera: Coccinellidae). Field surveys showed that several predators responded rapidly to expanding and increasing populations of the soybean aphid. Coccinellidae were the most important aphidophagous predators observed in 2002 (58.6%) and 2003 (44.8%), with mainly four native and naturalized species co-occurring with the soybean aphid throughout the growing season. Measurement of fitness parameters under laboratory conditions (survival, development time, longevity, fecundity) indicated that A. glycines is an excellent prey for the development and reproduction of all three of the coccinellid species studied. The intrinsic rate of natural increase (rm) was highest for H. axyridis (0.238 d−1), intermediate for P. quatuordecimpunctata (0.215 d−1) and lowest for C. maculata (0.134 d−1).  相似文献   
82.
The human pancreatic cell line BxPC-3 displays two classes of binding sites with high and low affinity for VIP. The order of potency of VIP-related peptides in inhibiting either [125I]VIP or [125I]N-AcPACAP27 binding and in stimulating cAMP production was typical of the human VIP receptor. By combining affinity labeling with glycosidase treatments, we have characterized the VIP receptor as a Mr = 68,200 glycoprotein, consisting of a Mr = 39,300 polypeptide core with at least three N-linked oligosaccharide chains. In addition, our results revealed the presence of a low amount of sialic acid residues in the carbohydrate moiety of receptor.  相似文献   
83.
Biomechanics and Modeling in Mechanobiology - Tissue layers can generally slide at the interface, accompanied by the dissipation due to friction. Nevertheless, it remains elusive how force could...  相似文献   
84.
Pneumonic-type lung adenocarcinoma (P-ADC) represents a distinct subset of lung cancer with specific clinical, radiological, and pathological features. Given the weak association with tobacco-smoking and the striking similarities with jaagsiekte sheep retrovirus (JSRV)-induced ovine pulmonary adenocarcinoma, it has been suggested that a zoonotic viral agent infecting pulmonary cells may predispose to P-ADC in humans. Our objective was to explore whether exposure to domestic small ruminants may represent a risk factor for P-ADC. We performed a multicenter case-control study recruiting patients with P-ADC as cases and patients with non-P-ADC non-small cell lung cancer as controls. A dedicated 356-item questionnaire was built to evaluate exposure to livestock. A total of 44 cases and 132 controls were included. At multivariate analysis, P-ADC was significantly more associated with female gender (Odds-ratio (OR)?=?3.23, 95% confidence interval (CI): 1.32-7.87, p?=?0.010), never-smoker status (OR?=?3.57, 95% CI: 1.27-10.00, p?=?0.015), personal history of extra-thoracic cancer before P-ADC diagnosis (OR?=?3.43, 95% CI: 1.10-10.72, p?=?0.034), and professional exposure to goats (OR?=?5.09, 95% CI: 1.05-24.69, p?=?0.043), as compared to other subtypes of lung cancer. This case-control suggests a link between professional exposure to goats and P-ADC, and prompts for further epidemiological evaluation of potential environmental risk factors for P-ADC.  相似文献   
85.

Background

Current guidelines for the prevention of cardiovascular disease (CVD) recommend diabetes as a CVD risk equivalent. However, reports that have examined the risk of diabetes in comparison to pre-existing CVD are lacking among older women. We aimed to assess whether diabetes was associated with a similar risk of total and cause-specific mortality as a history of CVD in older women.

Methodology/Principal Findings

We studied 9218 women aged 68 years or older enrolled in a prospective cohort study (Study of Osteoporotic Fracture) during a mean follow-up period of 11.7 years and compared all-cause, cardiovascular and coronary heart disease mortality among 4 groups: non-diabetic women with and without existing CVD, diabetic women with and without existing CVD. Mean (SD) age of the participants was 75.2 (5.3) years, 3.5% reported diabetes and 6.8% reported existing CVD. During follow-up, 5117 women died with 36% from CVD. The multivariate adjusted risk of cardiovascular mortality was increased among both non-diabetic women with CVD (hazard ratio (HR) 2.32, 95% CI: 1.97–2.74, P<0.001) and diabetic women without CVD (HR 2.06, CI: 1.62–2.64, P<0.001) compared to non-diabetic women without existing CVD. All-cause, cardiovascular and coronary mortality of non-diabetic women with CVD were not significantly different from diabetic women without CVD.

Conclusions/Significance

Older diabetic women without CVD have a similar risk of cardiovascular mortality compared to non-diabetic women with pre-existing CVD. The equivalence of diabetes and CVD seems to extend to older women, supporting current guidelines for cardiovascular prevention.  相似文献   
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88.
Modifications of the Illinois River and associated tributaries have resulted in altered hydrologic cycles and persistent river‐floodplain connections during the growing season that frequently impede the establishment of hydrophytic vegetation and have reduced value for migratory waterfowl and other waterbirds. To help guide floodplain restoration, we compared energetic carrying capacity for waterfowl in two wetland complexes along the Illinois River under different management regimes during 2012–2015. The south pool of Chautauqua National Wildlife Refuge (CNWR) was seasonally flooded due to a partial river connection and managed for moist‐soil vegetation. Emiquon Preserve was hydrologically isolated from the Illinois River by a high‐elevation levee and managed as a semipermanently flooded emergent marsh. Semipermanent emergent marsh management at Emiquon Preserve produced 5,495 energetic use‐days (EUD)/ha for waterfowl and other waterbirds across wetland cover types and years, and seasonal moist‐soil management at CNWR produced 6,199 EUD/ha in one of 4 years. At Emiquon Preserve, the aquatic bed cover type produced 9,660 EUD/ha, followed by 5,261 EUD/ha in moist‐soil, 1,398 EUD/ha in persistent emergent, 1,185 EUD/ha in hemi‐marsh, and 12 EUD/ha in open water cover types. At CNWR, the annual grass and sedge cover type produced 7,031 EUD/ha, followed by 5,618 EUD/ha in annual broadleaf and 1,305 EUD/ha in perennial grass cover types. Restoration of floodplain wetlands in isolation from frequent flood pulses during the growing season can produce hemi‐marsh and aquatic bed vegetation communities that provide high‐quality habitat for waterfowl and which have been mostly eliminated from large river systems in the Midwest, U.S.A.  相似文献   
89.
Background aimsMesenchymal stromal cells (MSCs) provide minor salivary glands (MSGs) with support and niche cells for epithelial glandular tissue. Little is known about resident MSG-derived MSCs (MSG-MSCs) in primary Sj?gren's syndrome (PSS). The authors’ objective is to define the immunobiology of endogenous PSS MSG-MSCs.MethodsUsing culture-adapted MSG-MSCs isolated from consenting PSS subjects (n = 13), the authors performed in vitro interrogation of PSS MSG-MSC immunobiology and global gene expression compared with controls. To this end, the authors performed phenotypic and immune functional analysis of indoleamine 2,3-dioxygenase (IDO), programmed death ligand 1 (PD-L1) and intercellular adhesion marker 1 (ICAM-1) before and after interferon γ (IFNγ) licensing as well as the effect of MSG-MSCs on T-cell proliferation. Considering the female predominance of PSS, the authors also addressed the influence of 17-β-estradiol on estrogen receptor α-positive-related MSC function.ResultsThe authors found that MSG-MSCs deployed normal immune regulatory functionality after IFNγ stimulation, as demonstrated by increased protein-level expression of IDO, PD-L1 and ICAM-1. The authors also found that MSG-MSCs suppressed T-cell proliferation in a dose-dependent manner independent of 17-β-estradiol exposure. Gene ontology and pathway analysis highlighted extracellular matrix deposition as a possible difference between PSS and control MSG-MSCs. MSG-MSCs demonstrated increased α-smooth muscle actin expression in PSS, indicating a partial myofibroblast-like adaptation.ConclusionsThese findings establish similar immune regulatory function of MSG-MSCs in both PSS and control patients, precluding intrinsic MSC immune regulatory defects in PSS. PSS MSG-MSCs show a partial imprinted myofibroblast-like phenotype that may arise in the setting of chronic inflammation, providing a plausible etiology for PSS-related glandular fibrosis.  相似文献   
90.
Ganglioside distribution was studied in peripheral nerves of normal controls and those of Trembler mutant mouse with defect in Schwann cell differentiation and myelination. Neuraminic acid content was considerably decreased in the mutant. Ganglioside distribution as evaluated by densitometry of resorcinol positive spots on thin-layer chromatography revealed a major peak for GDla in normal controls. In the mutant, the relative proportion was modified with qualitative modifications in the GDla area and a tremendous increase in GM3 content. The relation with the intense Schwann cell proliferation observed in the mutant is discussed.  相似文献   
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