1,280 research outputs found
Exploiting the Circadian Clock for Improved Cancer Therapy: Perspective From a Cell Biologist
Beauveria bassiana strain ATCC 74040 (Naturalis®), a valuable tool for the control of the cherry fruit fly (Rhagoletis cerasi)
Naturalis® is a bioinsecticide based on living conidiospores of the naturally occuring
Beauveria bassiana strain ATCC 74040. The entomopathogenic fungus acts primarily by
contact: once attached to the insect’s cuticle, the conidiospores germinate producing
penetration hyphae, which enter and proliferate inside the insect’s body. The fungus
invades and feeds on its host, causing its death due to dehydration and/or depletion of
nutrients. Several years of laboratory, semi-field and field studies showed that also Tephritid
flies (Ceratitis capitata, Rhagoletis cerasi, Bactrocera oleae) are susceptible to infection by
B. bassiana strain ATCC 74040. The results of efficacy trials conducted in 2004-05 are
reported. Naturalis was tested both alone and in an integrated pest management strategy.
The product showed high efficacy in controlling R. cerasi, comparable to or higher than
that of the chemical reference treatment. The B. bassiana-based product Naturalis can thus
be considered an efficient tool for the control of the cherry fruit fly
Effectiveness of entomopathogenic nematodes in the control of Cydia pomonella larvae in Northern Italy
Since 2006, a large scale research on the effectiveness of entomopathogenic nematodes
(EPN) in the control of codling moth (CM), Cydia pomonella, overwintering larvae has
been performed on about 35 ha of pear orchards per year in Emilia-Romagna, Northern
Italy. Steinernema carpocapsae and Steinernema feltiae activity was checked after spray
applications of EPNs to the trunk and branches. In 2006, the treatment was applied either
in spring or in autumn at different doses, before CM pupation; in 2007 the EPN treatment
was applied only in autumn at 1.5 x 109 I.J. ha –1. Every year it was distributed by means of
a conventional mist blower. The larval mortality was assessed directly on sentinel larvae in
card boards on the trunks and indirectly on the eggs laid by the females of the first CM
generation in spring. Moreover, each year, a trial was performed applying only S.
carpocapsae on sentinel larvae with the aim of testing this nematode at suitable
temperatures but at different water volumes.
The CM sentinel larvae were effectively parasitized after autumnal EPN application.
Moreover, the egg assessment demonstrated a good decrease in CM population in spring
2007, when EPNs had been applied at the best weather conditions (t° 12-14 °C and rain)
in the previous autumn
Does non-random segregation of DNA-strands occur during stem cell division in Macrostomum lignano?
Mutations of penicillin acylase residue B71 extend substrate specificity by decreasing steric constraints for substrate binding
Two mutant forms of penicillin acylase from Escherichia coli strains, selected using directed evolution for the ability to use glutaryl-L-leucine for growth [Forney, Wong and Ferber (1989) Appl. Environ. Microbiol. 55, 2550-2555], are changed within one codon, replacing the B-chain residue Phe(B71) with either Cys or Leu. Increases of up to a factor of ten in k(cat)/K-m values for substrates possessing a phenylacetyl leaving group are consistent with a decrease in K-s. Values of k(cat/)K(m) for glutaryl-L-leucine are increased at least 100-fold. A decrease in k(cat)/K-m for the CySB71 mutant with increased pH is consistent with binding of the uncharged glutaryl group. The mutant proteins are more resistant to urea denaturation monitored by protein fluorescence, to inactivation in the presence of substrate either in the presence of urea or at high pH, and to heat inactivation. The crystal structure of the Leu(B71) mutant protein, solved to 2 X resolution, shows a flip of the side chain of Phe(B256) into the periphery of the catalytic centre, associated with loss of the pi-stacking interactions between Phe(B256) and Phe(B71). Molecular modelling demonstrates that glutaryl-L-leucine may bind with the uncharged glutaryl group in the S-1 subsite of either the wild-type or the Leu(B71) mutant but with greater potential freedom of rotation of the substrate leucine moiety in the complex with the mutant protein. This implies a smaller decrease in the conformational entropy of the substrate on binding to the mutant proteins and consequently greater catalytic activity
Exploiting the Circadian Clock for Improved Cancer Therapy: Perspective From a Cell Biologist
Restraining and unleashing chromatin remodelers - structural information guides chromatin plasticity.
Chromatin remodeling enzymes are large molecular machines that guard the genome by reorganizing chromatin structure. They can reposition, space and evict nucleosomes and thus control gene expression, DNA replication and repair. Recent cryo-electron microscopy (cryo-EM) analyses have captured snapshots of various chromatin remodelers as they interact with nucleosomes. In this review, we summarize and discuss the advances made in our understanding of the regulation of chromatin remodelers, the mode of DNA translocation, as well as the influence of associated protein domains and remodeler subunits on the specific functions of chromatin remodeling complexes. The emerging structural information will help our understanding of disease mechanisms and guide our knowledge toward innovative therapeutic interventions. Copyright © 2020 Elsevier Ltd. All rights reserved
PARG: A Macrodomain in Disguise
Our understanding of poly-ADP-ribosylation as a posttranslational modification was limited by the lack of structural information on poly-ADP-ribose (PAR) hydrolysing enzymes. A recent study in Nature (Slade et al., 2011) reports the structure of PAR glycohydrolase (PARG), revealing unexpected similarity to the ubiquitous ADP-ribose-binding macrodomains
Long term outcome and quality of life after open incisional hernia repair - light versus heavy weight meshes
<p>Abstract</p> <p>Background</p> <p>Mesh repair of incisional hernia is superior to the conventional technique. From all available materials for open surgery polypropylene (PP) is the most widely used. Development resulted in meshes with larger pore size, decreased mesh surface and lower weight. The aim of this retrospective non randomized study was to compare the quality of life in the long term follow up (> 72 month) after incisional hernia repair with "light weight"(LW) and "heavy weight"(HW) PP meshes.</p> <p>Methods</p> <p>12 patients who underwent midline open incisional hernia repair with a HW-PP mesh (Prolene<sup>® </sup>109 g/m<sup>2 </sup>pore size 1.6 mm) between January 1996 and December 1997 were compared with 12 consecutive patients who underwent the same procedure with a LW-PP mesh (Vypro<sup>® </sup>54 g/m<sup>2</sup>, pore size 4-5 mm) from January 1998. The standard technique was the sublay mesh-plasty with the retromuscular positioning of the mesh. The two groups were equal in BMI, age, gender and hernia size. Patients were routinely seen back in the clinic.</p> <p>Results</p> <p>In the long term run (mean follow up 112 ± 22 months) patients of the HW mesh group revealed no significant difference in the SF-36 Health Survey domains compared to the LW group (mean follow up 75 ± 16 months).</p> <p>Conclusions</p> <p>In this study the health related quality of life based on the SF 36 survey after open incisional hernia repair with light or heavy weight meshes is not related to the mesh type in the long term follow up.</p
Plasma adiponectin levels and sonographic phenotypes of subclinical carotid artery atherosclerosis : Data from the SAPHIR study
Copyright: Copyright 2008 Elsevier B.V., All rights reserved.Background and Purpose - Adipose tissue produces and secretes a number of bioactive molecules, conceptualized as adipocytokines. Adiponectin has been identified as one of the adipocytokines, and hypoadiponectinemia was demonstrated in patients with obesity, diabetes mellitus, and coronary artery disease. Whether decreased adiponectin levels are cause or consequence is an important issue in the discussion on the association between adiponectin and atherosclerosis. In the present study, we investigated the association of plasma adiponectin levels with sonographic phenotypes of subclinical atherosclerosis, which may represent different stages of disease as well as common and distinct determinants. Methods - A total of 1515 middle-aged healthy white subjects (940 males and 575 females) were included. Common carotid artery intima-media thickness (CIMT) and presence of atherosclerotic plaques were assessed by B-mode ultrasound. Results - After adjustment for established risk factors, per 1 μg/mL decrease in adiponectin CIMT increased on the average by 3.48 μ in males (95% CI, 1.23 to 5.73 μm) and by 2.39 μ in females (95% CI, 0.50 to 4.27 μm). After dichotomizing adiponectin levels at the median and adjustment for established risk factors, the mean difference of CIMT between subjects with low and high adiponectin levels was 20.42 μm in men (95% CI, 6.80 to 34.04; P=0.003) and 20.75 μ in women (95% CI, 1.08 to 40.42; P=0.039). No significant relationship was found between adiponectin levels and presence of atherosclerotic plaques. Conclusion - Our results demonstrate an independent negative association of adiponectin levels and CIMT, whereas no relationship with presence of atherosclerotic plaques was found, thus suggesting hypoadiponectinemia as a risk factor in the development of early atherosclerosis.publishersversionPeer reviewe
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