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51.
Raul Abreu de Assis Luca Pietro Casacci Simona Bonelli Francesca Barbero Luciana Mafalda Elias de Assis Ezio Venturino 《Bulletin of mathematical biology》2018,80(9):2378-2407
A model of interspecific host competition in a system with one parasite (butterfly—Maculinea) and multiple potential hosts (ants—Myrmica) is presented. Results indicate that host interspecific competition increases the occurrence of multiple host behaviour in Maculinea natural populations but decreases the ability of the parasite populations to adapt to the most abundant host species. These qualitative predictions were compared with data on host specificity, with good agreement. Analysis of the data also indicates that Maculinea teleius and Maculinea arion respond differently to changes in relative host abundances. Maculinea teleius shows a larger fraction of sites where it displays multiple host behaviour and a larger fraction of sites where the niches of the hosts overlap. In some instances, Maculinea teleius is adapted to Myrmica hosts that are present in lower frequencies. Maculinea arion is locally more host-specific and occurs at sites where host interspecific competition is unlikely and is more frequently adapted to the most abundant host species. 相似文献
52.
Kathleen L. Summers Patrick Lippiello Steven Verhulst Ezio Giacobini 《Neurochemical research》1995,20(9):1089-1094
The effects of nicotinic receptor agonists 5-fluoronicotine, noranhydroecgonine and pyridyl-methylpyrrolidine on the cortical release of acetylcholine (ACh), norepinephrine (NE), dopamine (DA) and serotonin (5-HT) were investigated with microdialysis in rat. 5-Fluoronicotine significantly elevated ACh to 76% above basal values and DA to 69% above baseline. Pyridyl-methylpyrrolidine significantly increased the release of ACh to 39% above basal values and NE to 63% above baseline. Noranhydroecgonine significantly elevated NE to 64% above basal values and DA to 147% above baseline. 5-Fluoronicotine did not affect NE release; pyridylmethylpyrrolidine did not alter DA release; and noranhydroecgonine did not significantly elevate ACh release. None of these agonists increased the release of 5-HT. All responses were blocked by prior administration of mecamylamine, a nicotinic receptor antagonist. The distinctive neurotransmitter-related profiles for the three agonists are suggestive of activity at subtypes of nicotinic receptors, an effect that may be related to the structural diversity of these compounds. 相似文献
53.
As the amount of biological data in the public domain grows, so does the range of modeling and analysis techniques employed in systems biology. In recent years, a number of theoretical computer science developments have enabled modeling methodology to keep pace. The growing interest in systems biology in executable models and their analysis has necessitated the borrowing of terms and methods from computer science, such as formal analysis, model checking, static analysis, and runtime verification. Here, we discuss the most important and exciting computational methods and tools currently available to systems biologists. We believe that a deeper understanding of the concepts and theory highlighted in this review will produce better software practice, improved investigation of complex biological processes, and even new ideas and better feedback into computer science. 相似文献
54.
Ezio Bombardelli Attilio Bonati Bruno Gabetta Giuseppe Mustich 《Phytochemistry》1974,13(11):2559-2562
The structures of sericic acid and sericoside, the major constituents of the roots of Terminalia sericea, have been determined. Sericic acid is 2α,3β,19α,24-tetrahydroxy-olean-12-en-28-oic acid and sericoside the corresponding C-28 D-glucosyl ester. 相似文献
55.
56.
Giovanni Di Gregorio Barletta Maria Vittoria Mariamichela Lanzilli Claudia Petrillo Ezio Ricca Rachele Isticato 《Environmental microbiology》2022,24(4):2078-2088
Bacterial spores of the Bacillus genus are ubiquitous in nature and are commonly isolated from a variety of diverse environments. Such wide distribution mainly reflects the spore resistance properties but some Bacillus species can grow/sporulate in at least some of the environments where they have been originally isolated. Growing and sporulating at different conditions is known to affect the structure and the resistance properties of the produced spore. In B. subtilis the temperature of growth and sporulation has been shown to influence the structure of the spore surface throughout the action of a sporulation-specific and heat-labile kinase CotH. Here we report that CotG, an abundant component of the B. subtilis spore surface and a substrate of the CotH kinase, assembles around the forming spore but also accumulates in the mother cell cytoplasm where it forms aggregates with at least two other coat components. Our data suggest that the thermo-regulator CotH contributes to the switch between the coat of 25°C and that of 42°C spores by controlling the phosphorylation levels of CotG that, in turn, regulates the assembly of at least two other coat components. 相似文献
57.
Ferrari A Venturino A Pechén de D'Angelo AM 《Comparative biochemistry and physiology. Toxicology & pharmacology : CBP》2007,146(3):308-313
The organophosphate azinphos methyl (AzMe) and the carbamate carbaryl are the insecticides mostly used in the irrigated valley of Río Negro and Neuquén, Patagonia, Argentina. Juvenile rainbow trout were exposed to AzMe and carbaryl and the sensitivity of skeletal muscular cholinesterase (ChE) and the time course of inhibition and recovery were evaluated. EC50 values demonstrated that AzMe was a stronger in vivo inhibitor of muscular ChE (1.05+/-0.23 microg/L) than carbaryl (270+/-62.23 microg/L). Muscular ChE was significantly less sensitive to both insecticides than brain ChE. EC50 values obtained for muscular ChE were closer than those for brain ChE to the respective pesticide lethal concentrations, pointing out the relevance of the muscular enzyme in determining acute toxicity. The recovery process of ChE activity after carbaryl exposure (500 microg/L) was fast, whereas no significant recovery was observed with AzMe (1 microg/L) after 21 days in uncontaminated media. Brain and muscular ChE were inhibited and showed a significant but not complete recovery after three consecutive 48-h exposures to AzMe (1 microg/L) followed by a recovery period of 7 days. This scheme mimics the periodical application of the insecticides in the region and suggests a certain probability of a sustained ChE inhibition under field conditions, affecting fish development and survival. 相似文献
58.
Bianucci R Rahalison L Ferroglio E Massa ER Signoli M 《Comptes rendus biologies》2007,330(10):747-754
A rapid diagnostic dipstick test (RDT) that detects Yersinia pestis F1 antigen has been recently applied on 18 putative plague victims exhumed from four archaeological burial sites in southeastern France dating back to the 16(th), 17(th) and 18(th) centuries. The Y. pestis antigen F1 was detected in 12 ancient samples out of 18 (67%). Negative controls confirmed their negativity (100%). Our results emphasize that the detection threshold of the RDT for plague (0.5 ng/ml) is sufficient for a first retrospective diagnosis of Y. pestis infection in ancient remains, and confirm the high specificity and sensitivity of the assay. Double-blind analyses performed by using two different techniques (RDT and 'suicide PCR') led us to the identification of the Y. pestis F1 antigen and the Y. pestis pla and gplD genes. These data provide clear evidence of the presence of Y. pestis in the examined specimens. 相似文献
59.
Bruno Andreoni Antonio Chiappa Emilio Bertani Massimo Bellomi Roberto Orecchia MariaGiulia Zampino Nicola Fazio Marco Venturino Franco Orsi Angelica Sonzogni Ugo Pace Lorenzo Monfardini 《World journal of surgical oncology》2007,5(1):1-10
Background
This study evaluates the surgical morbidity and long-term outcome of colorectal cancer surgery in an unselected group of patients treated over the period 1994–2003.Methods
A consecutive series of 902 primary colorectal cancer patients (489 M, 413 F; mean age: 63 years ± 11 years, range: 24–88 years) was evaluated and prospectively followed in a university hospital (mean follow-up 36 ± 24 months; range: 3–108 months). Perioperative mortality, morbidity, overall survival, curative resection rates, recurrence rates were analysed.Results
Of the total, 476 colorectal cancers were localized to the colon (CC, 53%), 406 to the rectum (RC, 45%), 12 (1%) were multicentric, and 8 were identified as part of HNPCC (1%). Combining all tumours, there were 186 cancers (20.6%) defined as UICC stage I, 235 (26.1%) stage II, 270 (29.9%) stage III and 187 (20.6%) stage IV cases. Twenty-four (2.7%) cases were of undetermined stage. Postoperative complications occurred in 38% of the total group (37.8% of CC cases, 37.2% of the RC group, 66.7% of the synchronous cancer patients and 50% of those with HNPCC, p = 0.19) Mortality rate was 0.8%, (1.3% for colon cancer, 0% for rectal cancer; p = 0.023). Multivisceral resection was performed in 14.3% of cases. Disease-free survival in cases resected for cure was 73% at 5-years and 72% at 8 years. The 5- and 8-year overall survival rates were 71% and 61% respectively (total cases). At 5-year analysis, overall survival rates are 97% for stage I disease, 87% for stage II, 73% for stage III and 22% for stage IV respectively (p < 0.0001). The 5-year overall survival rates showed a marked difference in R0, R1+R2 and non resected patients (82%, 35% and 0% respectively, p < 0.0001). On multivariate analysis, resection for cure and stage at presentation but not tumour site (colon vs. rectum) were independent variables for overall survival (p < 0.0001).Conclusion
A prospective, uniform follow-up policy used in a single institution over the last decade provides evidence of quality assurance in colorectal cancer surgery with high rates of resection for cure where only stage at presentation functions as an independent variable for cancer-related outcome. 相似文献60.
Antonino Cusumano Ezio Peri S. Bradleigh Vinson Stefano Colazza 《Entomologia Experimentalis et Applicata》2012,143(2):155-163
Ongoing studies by our group showed that the outcome of the intrinsic competition between two solitary egg parasitoids, Trissolcus basalis (Wollaston) (Hymenoptera: Scelionidae) and Ooencyrtus telenomicida (Vassiliev) (Hymenoptera: Encyrtidae), is dominated by O. telenomicida. In this article we investigated the role played by the ovipositing O. telenomicida female in the suppression of a T. basalis competitor. Laboratory experiments were conducted by allowing an O. telenomicida female to puncture the eggs of Nezara viridula (L.) (Heteroptera: Pentatomidae) with her ovipositor (= no oviposition) or to parasitize them. The results show that O. telenomicida relies on some physiological mechanisms to mediate its interspecific intrinsic competition with T. basalis. In fact, the emergence of T. basalis was strongly reduced in host eggs that were parasitized either before or after being punctured by O. telenomicida at fixed time intervals (5, 15, 30, or 45 h). The low percentage of emergence of T. basalis (ranging from approximately 4–20%) was a consequence of the delay and growth rate reduction of larval development. Furthermore, the percentage of eclosion of N. viridula nymphs was negatively affected by the O. telenomicida female’s punctures (96% from healthy host eggs, 4% from punctured host eggs). Host eggs punctured or oviposited in by O. telenomicida showed alterations in the ooplasm including some melanized‐like areas near the hole made with the ovipositor; such alterations indicate that the adult parasitoid releases substances that affect the host eggs survival. These results suggest that the O. telenomicida female influences both the physiological interspecific parasitoid‐parasitoid interaction, as well as the host‐parasitoid interaction, providing, for the first time in egg parasitoids, evidence that physiological suppression of some competitive egg parasitoids is mediated by the ovipositing female. 相似文献