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61.
Behaviours or traits associated with aggression and communication may increase an animal's conspicuousness to predators or parasitoids. Most examples of this come from instances of aggression or communication within a species. We tested whether interspecific encounters between ants enhance the host location success of a parasitoid (Diptera: Phoridae) that attacks ants in the genus Linepithema. At food resources recruited to by Linepithema, parasitoid discovery rates were lower when Linepithema was alone than when other ant species were present. In experimentally controlled encounters, parasitoid discovery rates were elevated when Linepithema confronted an ant species that elicited use of chemicals, but not when it confronted an ant species that primarily elicited physical aggression. These results indicate that phorid parasitoids of Linepithema use the ant's chemicals as host location cues. Because Linepithema is known to abandon food resources in the presence of its phorid parasitoids, its use of chemicals during interspecific encounters may diminish its competitive success when phorids are nearby. Copyright 2003 Published by Elsevier Science Ltd on behalf of The Association for the Study of Animal Behaviour. 相似文献
62.
Rosane Aparecida Ribeiro Sandra Lucinei Balbo Letícia Prates Roma Rafael Ludemann Camargo Luiz Felipe Barella Emerielle Cristine Vanzela Paulo Cesar de Freitas Mathias Everardo Magalhães Carneiro Antonio Carlos Boschero Maria Lúcia Bonfleur 《Molecular biology reports》2013,40(7):4521-4528
Monosodium glutamate-obese rats are glucose intolerant and insulin resistant. Their pancreatic islets secrete more insulin at increasing glucose concentrations, despite the possible imbalance in the autonomic nervous system of these rats. Here, we investigate the involvement of the cholinergic/protein kinase (PK)-C and PKA pathways in MSG β-cell function. Male newborn Wistar rats received a subcutaneous injection of MSG (4 g/kg body weight (BW)) or hyperosmotic saline solution during the first 5 days of life. At 90 days of life, plasma parameters, islet static insulin secretion and protein expression were analyzed. Monosodium glutamate rats presented lower body weight and decreased nasoanal length, but had higher body fat depots, glucose intolerance, hyperinsulinemia and hypertrigliceridemia. Their pancreatic islets secreted more insulin in the presence of increasing glucose concentrations with no modifications in the islet-protein content of the glucose-sensing proteins: the glucose transporter (GLUT)-2 and glycokinase. However, MSG islets presented a lower secretory capacity at 40 mM K+ (P < 0.05). The MSG group also released less insulin in response to 100 μM carbachol, 10 μM forskolin and 1 mM 3-isobutyl-1-methyl-xantine (P < 0.05, P < 0.0001 and P < 0.01). These effects may be associated with a the decrease of 46 % in the acetylcholine muscarinic type 3 (M3) receptor, and a reduction of 64 % in PKCα and 36 % in PKAα protein expressions in MSG islets. Our data suggest that MSG islets, whilst showing a compensatory increase in glucose-induced insulin release, demonstrate decreased islet M3/PKC and adenylate cyclase/PKA activation, possibly predisposing these prediabetic rodents to the early development of β-cell dysfunction. 相似文献
63.
Methods to produce marker-free transgenic plants 总被引:2,自引:0,他引:2
Selectable marker genes (SMGs) have been extraordinarily useful in enabling plant transformation because of the low efficiency of transgene integration. The most used SMGs encode proteins resistant to antibiotics or herbicides and use negative selection, i.e., by killing nontransgenic tissue. However, there are perceived risks in wide-scale deployment of SMG-transgenic plants, and therefore research has recently been performed to develop marker-free systems. In this review, transformation using markers not based on antibiotic or herbicide resistance genes, as well as different systems of marker gene deletion, are discussed. 相似文献
64.
Kohei Hasegawa Yusuke Tsugawa Chu-Lin Tsai David FM Brown Carlos A Camargo Jr 《Respiratory research》2014,15(1):40
Background
Little is known about patients who frequently visit the emergency department (ED) for acute exacerbation of chronic obstructive pulmonary disease (AECOPD). We aimed to quantify the proportion and characteristics of patients with frequent ED visits for AECOPD and associated healthcare utilization.Methods
We conducted a retrospective cohort study of adults aged ≥40 years with at least one ED visit for AECOPD between 2010 and 2011, derived from population-based all-payer data of State ED and Inpatient Databases for two large and diverse states: California and Florida. Outcome measures were frequency of ED visits for AECOPD, 30-day ED revisits, subsequent hospitalizations, near-fatal events (AECOPD involving mechanical ventilation), and charges for both ED and inpatient services (available only for Florida) during the year after the first ED visit.Results
The analytic cohort comprised 98,280 unique patients with 154,736 ED visits for AECOPD. During the 1-year period, 29.4% (95% CI, 29.1%-29.7%) of the patients had two or more (frequent) visits, accounting for 55.2% (95% CI, 54.9%-55.4%) of all ED visits for AECOPD. In the multivariable model, significant predictors of frequent ED visits were age 55–74 years (vs. 40–54 years), male sex, non-Hispanic white or black race, Medicaid insurance (vs. private), and lower median household income (all P < 0.001). At the visit-level, 12.3% of ED visits for AECOPD were 30-day revisit events (95% CI, 12.1%-12.4%). Additionally, 62.8% of ED visits for AECOPD (95% CI, 62.6%-63.0%) resulted in a hospitalization; patients with frequent ED visits comprised 55.5% (95% CI, 55.2%-55.8%) of all hospitalizations. Furthermore, 7.3% (95% CI, 7.3%-7.5%) of ED visits for AECOPD led to a near-fatal event; patients with frequent ED visits accounted for 64.4% (95% CI, 63.5%-65.3%) of all near-fatal events. Total charges for AECOPD were $1.94 billion (95% CI, $1.90-1.97 billion) in Florida; patients with frequent ED visits accounted for $1.07 billion (95% CI, $1.04-1.09 billion).Conclusions
In this large cohort study, we found that 29% had frequent ED visits for AECOPD and that lower socioeconomic status was significantly associated with a higher frequency of ED visits. Individuals with frequent ED visits for AECOPD accounted for a substantial amount of healthcare utilization and financial burden. 相似文献65.
M. R. Abreu I. Delalibera N. R. C. Pereira M. I. Camargo‐Mathias 《Medical and veterinary entomology》2021,35(1):88-96
The tick Rhipicephalus sanguineus sensu lato has great medical and veterinary importance, mainly because the ability to transmit many diseases, causing harm to pets but also risks to public health. The blood spoliation and transmission of pathogens occur because of the immunosuppressive action of these ticks' saliva, a potent mixture of bioactive substances that is secreted by the salivary glands, one of the organs responsible for their biological success, and hence the target of studies for their control. Ozone has promise for use as an alternative acaricide, due to its proven efficiency in controlling agricultural and food pests, besides posing no risk of environmental contamination or to animal and human health. Therefore, this study evaluated the acaricidal potential of exposure of females of R. sanguineus s.l. to ozonated water at many concentrations and analysed the morphophysiological alterations of the salivary glands, employing histological and light microscopic techniques. The results demonstrated that the ozonated water at the concentrations investigated caused severe alterations in the salivary glands, bringing a new perspective for control of R. sanguineus s.l., through an ecologically correct method due to the absence of harm to non‐target organisms and the environment. 相似文献
66.
Cassiolato Ana Paula Camargo Carlos Henrique Piccoli Cecconi Maria Cristina Christakis Sandra Gonçalves Claudia Regina Rodrigues Campos Karoline Takenori Higa Fabio Andrade Pereira Gabriela de Moraes Camile Silva de Lemos Ana Paula 《International microbiology》2023,26(3):611-618
International Microbiology - Invasive meningococcal disease (IMD) is a major health problem. Given the post-COVID-19 pandemic scenario with the loosening of the non-pharmacological measures to... 相似文献
67.
The ovary of the tick Amblyomma triste is classified as panoistic, which is characterized by the presence of oogonia without nurse and follicular cells. The present study has demonstrated that the oocytes in all developmental stages (I-IV) are attached to the ovary through a pedicel, a cellular structure that synthesizes and provides carbohydrate, lipids and proteins supplies for the oocytes during the vitellogenesis process. The lipids are deposited during all oocyte stages; they are freely distributed as observed in stages II, III and IV or they form complexes with other elements. The proteins are also deposited in all stages of the oocytes, however, in lower concentration in the stage IV. There is carbohydrate deposition from oocytes in the stage II as well as in stages III and IV. In addition, the present work has demonstrated that the oocyte yolk of A. triste has a glycolipoprotein nature and the elements are deposited in the following sequence: firstly the lipids and proteins, and finally the carbohydrates. 相似文献
68.
R. A. Marenco M. A. B. Camargo S. A. Antezana-Vera M. F. Oliveira 《Photosynthetica》2017,55(4):679-688
Tropical rainforest trees adjust leaf traits during ontogeny to cope with changes in the physical environment and maximize their carbon uptake. The aim of this study was to determine the plasticity index (PI) of leaf traits in understory and canopy leaves of six Amazonian tree species. In four of the six species the PI of leaf traits varied within species, and in four of the ten leaf traits assessed, the PI differed between species. The greatest PI values were found for stomatal density (Ds) and CO2-saturated photosynthesis, and the lowest ones were found for stomatal size, and leaf thickness. Despite the differences in PI values within species, the mean PI was similar in all the six species. As the saplings grow toward the canopy, the strategy to increase carbon uptake involves increasing Ds and leaf nitrogen and reducing stomatal size. 相似文献
69.
Razvan C. Stan Darshak K. Bhatt Maristela M. de Camargo 《BioEssays : news and reviews in molecular, cellular and developmental biology》2020,42(1):1900115
The ability to memorize changes in the environment is present at all biological levels, from social groups and individuals, down to single cells. Trans-generational memory is embedded subcellularly through genetic and epigenetic mechanisms. Evidence that cells process and remember features of the immediate environment using protein sensors is reviewed. It is argued that this mnemonic ability is encapsulated within the protein conformational space and lasts throughout its lifetime, which can overlap with the lifespan of the organism. Means to determine diachronic changes in protein activity are presented. 相似文献
70.
Pavanelli WR Kaminami MS Geres JR Sano A Ono MA Camargo IC Itano EN 《Mycopathologia》2007,163(3):117-128
Paracoccidioidomycosis (PCM) is a granulomatous disease caused by a dimorphic fungus, Paracoccidioides brasiliensis. The present study investigated the protective activity of the P. brasiliensis high-molecular-mass (hMM) fraction (~380 kDa) in experimental murine PCM. In the first step, lymphocyte proliferation and
production of IFNγ (but not IL-4) were observed in “in vitro” spleen cells (from female BALB/c mice infected (i.v.) with P. brasiliensis) that were stimulated with hMM fractions. In the second step, female BALB/c mice were previously immunized (s.c.) with hMM
fraction (25 μg/protein = F-25 and 50 μg/protein = F-50), and the colony-forming units (CFU) of the lung and spleen, the histopathological
characteristics of the granulomatous lesions, and plasmatic gp43 soluble antigens and anti-hMM IgG levels were analyzed at
28 and 56 days after infection. The lung and liver CFU were lower in mice previously immunized with the hMM fraction (P < 0.05). The granulomatous lesions revealed a greater degree of compaction and organization, with no dissemination of the
fungus to other organs. Lower soluble antigen levels (P < 0.05) and higher IgG anti-hMM fraction (P < 0.05) were observed in immunized groups. The results for CFU, histopathology and antigenemia suggest that the hMM fraction
has a protective effect in experimental paracoccidioidomycosis in BALB/c mice. 相似文献