526 research outputs found
Heterogeneous Distribution of Ecto-Ca-ATPases in Primary Cultures of Human Adenohypophyseal Cells
The aim of this study was to investigate the localization of ecto-Ca-adenosine-triphosphatase (ecto-Ca-ATPase) in different parenchymal cells of the human pituitary in tissue culture. The distribution of ecto-ATPases on the surface membrane of a particular parenchymal cell varied with the type of cells in contact with this parenchymal cell; the membrane portions immediately exposed to the medium showed low if any ecto-ATPase activity. These results suggest that ecto-Ca-ATPases of the parenchymal cells may be involved in cell adhesion processes and may be of crucial importance in the organization (in vivo) and reorganization (in vitro) of human adenohypophyseal tissue
MIKOTOKSINI I ZDRAVLJE ŽIVOTINJA: OD OKCIDACIJSKOG STRESA DO ISPOLJAVANJA GENA
Mycotoxin contamination of the feed and food is a global problem. There are several unresolved questions in this regard. Firstly, more than 25% of world grain production is contaminated by mycotoxins. In particular, Fusarium mycotoxins (so called field mycotoxins) contaminate up to 100% of the grain. Since these mycotoxins come from the field it is difficult to deal with them and various technological approaches including plant selection for mycotoxin resistance have not produced any significant results. Secondly, in nature there are more than 300 mycotoxins, but analytical techniques for routine mycotoxins analysis have been developed only for about 30 major mycotoxins. Therefore, if there is a conclusion from the analytical lab that “mycotoxins have not been found” this means that 10-30 mycotoxins analyzed were not found. As for others, there is no answer. Thirdly, sampling for mycotoxins analysis is extremely difficult and is an important source of errors. Fourthly, there are no safe levels of mycotoxins, because of synergistic interactions of many mycotoxins: several mycotoxins in low concentrations could cause more problems than a single mycotoxin at a higher dose. Recent results show that in many cases membrane-active properties of various mycotoxins determine their toxicity. Indeed, incorporation of mycotoxins into membrane structures causes various detrimental changes. These changes are associated with alteration of fatty acid composition of the membrane structures and with peroxidation of long chain PUFAs inside membranes. This ultimately damages membrane receptors, causing alterations in second messenger systems; inactivation of a range of membrane-binding enzymes responsible for regulation of important pathways. Finally, this causes alterations in membrane permeability, flexibility and other important characteristics determining membrane function. Detrimental effects of mycotoxins on DNA, RNA and protein synthesis together with pro-apoptotic action further compromise important metabolic pathways. Consequently, changes in physiological functions including growth, development and reproduction occur. Importance of oxidative stress and lipid peroxidation in all these processes is confirmed by protective effects of natural antioxidants against mycotoxin toxicity. However, protective effects of antioxidants including selenium are of limited value and a combination of mycotoxin binders with natural antioxidants could be the next step in preventing damaging effects of mycotoxins in animal and poultry production.Kontaminiranje hrane mikotoksinima je globalni problem. S tim u svezi nekoliko je neriješenih pitanja. Prvo, više od 25% svjetske proizvodnje žitarica kontaminirano je mikotoksinima. Osobito mikotoksini fuzarijuma (tzv.poljski mikotoksini) kontaminiraju do 100% žitarica. Budući da ovi mikotoksini dolaze iz polja teško ih je suzbiti pa i različiti tehnički postupci uključujući i selekciju biljaka na otpornost na mikotoksine nisu dali značajnije rezultate. Drugo, razvijene analize odnose se samo na oko 30 važnijih mikotoksina. Zato ako je i nalaz analitičkog laboratorija da "nisu nađeni mikotoksini" znači da nije nađeno 10-30 analiziranih mikotoksina. Što se tiče ostalih, nema odgovora. Treće, uzorkovanje za analizu mikotoksina vrlo je teško i važan je izvor pogrešaka. Četvrto, nema sigurnih razina mikotoksina zbog sinergetskih interakcija mnogih mikotoksina: nekoliko mikotoksina u malim koncentracijama
može prouzročiti više problema nego jedan štetan u većoj količini. Noviji rezultati pokazuju da u mnogo slučajeva svojstva aktivne membrane raznih mikotoksina određuju njihovu toksičnost. Doista, ugrađivanje mikotoksina u strukture membrane uzrokuje razne štetne promjene. Te su promjene povezane s promjenom sastava masnih kiselina strukture membrane i s peroksidacijom drugog lanca PUFA-e u membrani. Ovo konačno oštećuje receptore membrane, prouzročivši promjene drugog niza enzima koji povezuju membranu i odgovorni su za reguliranje važnih puteva. Konačno, to prouzrokuje promjene u propusnosti membrane, fleksibilnosti i drugim važnim značajkama koje određuju funkciju membrane. Štetno djelovanje mikotoksina na DNK, RNA i sintezu bjelančevina zajedno s proapoptotičnim djelovanjem dalje djeluje na važne metaboličke puteve. Konačno dolazi do promjene u fiziološkim funkcijama, uključujući rast, razvoj i reprodukciju. Važnost oksidacijskog stresa i peroksidacije lipida u svim tim procesima potvrđuje zaštitno djelovanje prirodnih antioksidanata protiv toksičnosti mikotoksina. Međutim, zaštitno djelovanje antioksidanata, uključujući selen, ograničene je vrijednosti i kombinacija. Vezanje mikotoksina s prirodnim antioksidantima mogao bi biti sljedeći korak u sprječavanju štetnog djelovanja u proizvodnji životinja i peradi
The Auto-Generated Fragment of the Usp1 Deubiquitylase Is a Physiological Substrate of the N-End Rule Pathway
Deamidation of N-terminal Gln by the Ntaq1 Nt^Q-amidase is a part of the Arg/N-end rule pathway, a ubiquitin-dependent proteolytic system. Here we identify Gln-Usp1^(Ct), the C-terminal fragment of the autocleaved Usp1 deubiquitylase, as the first physiological Arg/N-end rule substrate that is targeted for degradation through deamidation of N-terminal Gln. Usp1 regulates genomic stability, in part through the deubiquitylation of monoubiquitylated PCNA, a DNA polymerase processivity factor. The autocleaved Usp1 remains a deubiquitylase because its fragments remain associated with Uaf1, an enhancer of Usp1 activity, until the Gln-Usp1^(Ct) fragment is selectively destroyed by the Arg/N-end rule pathway. We also show that metabolic stabilization of Gln-Usp1^(Ct) results in a decreased monoubiquitylation of PCNA and in a hypersensitivity of cells to ultraviolet irradiation. Thus, in addition to its other functions in DNA repair and chromosome segregation, the Arg/N-end rule pathway regulates genomic stability through the degradation-mediated control of the autocleaved Usp1 deubiquitylase
Development And Characterization Of Microsatellite Markers For Piptadenia Gonoacantha (fabaceae)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Premise of the study: Microsatellite primers were designed for Piptadenia gonoacantha (Fabaceae) and characterized to estimate genetic diversity parameters. The species is a native tree from the Atlantic Forest biome commonly used in forest restoration; it has medicinal potential and the wood is economically useful. Methods and Results: Twenty-eight microsatellite loci were identified from an enriched genomic library. Fifteen loci resulted in successful amplifications and were characterized in a natural population of 94 individuals. Twelve loci were polymorphic, with allele numbers ranging from three to 15 per locus, and expected and observed heterozygosities ranging from 0.2142 to 0.8325 and 0.190 to 0.769, respectively. Conclusions: The developed markers will be used in further studies of population genetics of P. gonoacantha, aimed at conservation and management of the species in natural populations and in forest restoration projects.32Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)FAPESP [Biota/FAPESP-11/50296-8]CNPq [CNPq-140036/2011-3
Association of symptoms of insomnia and sleep parameters among kidney transplant recipients
Objective: Insomnia complaints are frequent among kidney transplant (kTx) recipients and are associated with fatigue, depression, lower quality of life and increased morbidity. However, it is not known if subjective insomnia symptoms are associated with objective parameters of sleep architecture. Thus, we analyze the association between sleep macrostructure and EEG activity versus insomnia symptoms among kTx recipients. Methods: Participants (n1 = 100) were selected from prevalent adult transplant recipients (n0 = 1214) followed at a single institution. Insomnia symptoms were assessed by the Athens Insomnia Scale (AIS) and standard overnight polysomnography was performed. In a subgroup of patients (n2 = 56) sleep microstructure was also analyzed with power spectral analysis. Results: In univariable analysis AIS score was not associated with sleep macrostructure parameters (sleep latency, total sleep time, slow wave sleep, wake after sleep onset), nor with NREM and REM beta or delta activity in sleep microstructure. In multivariable analysis after controlling for covariables AIS score was independently associated with the proportion of slow wave sleep (β = 0.263; CI: 0.026–0.500) and REM beta activity (β = 0.323; CI = 0.041–0.606) (p < 0.05 for both associations). Conclusions: Among kTx recipients the severity of insomnia symptoms is independently associated with higher proportion of slow wave sleep and increased beta activity during REM sleep but not with other parameters sleep architecture. The results suggest a potential compensatory sleep protective mechanism and a sign of REM sleep instability associated with insomnia symptoms among this population
Development and characterization of microsatellite markers for Piptadenia Gonoacantha (fabaceae)
Microsatellite primers were designed for Piptadenia gonoacantha (Fabaceae) and characterized to estimate genetic diversity parameters. The species is a native tree from the Atlantic Forest biome commonly used in forest restoration; it has medicinal potential and the wood is economically useful. Twenty-eight microsatellite loci were identified from an enriched genomic library. Fifteen loci resulted in successful amplifications and were characterized in a natural population of 94 individuals. Twelve loci were polymorphic, with allele numbers ranging from three to 15 per locus, and expected and observed heterozygosities ranging from 0.2142 to 0.8325 and 0.190 to 0.769, respectively. The developed markers will be used in further studies of population genetics of P. gonoacantha, aimed at conservation and management of the species in natural populations and in forest restoration projects32CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP140036/2011-3sem informaçãoBiota/FAPESP-11/50296-
Dependence of paracentric inversion rate on tract length
BACKGROUND: We develop a Bayesian method based on MCMC for estimating the relative rates of pericentric and paracentric inversions from marker data from two species. The method also allows estimation of the distribution of inversion tract lengths. RESULTS: We apply the method to data from Drosophila melanogaster and D. yakuba. We find that pericentric inversions occur at a much lower rate compared to paracentric inversions. The average paracentric inversion tract length is approx. 4.8 Mb with small inversions being more frequent than large inversions. If the two breakpoints defining a paracentric inversion tract are uniformly and independently distributed over chromosome arms there will be more short tract-length inversions than long; we find an even greater preponderance of short tract lengths than this would predict. Thus there appears to be a correlation between the positions of breakpoints which favors shorter tract lengths. CONCLUSION: The method developed in this paper provides the first statistical estimator for estimating the distribution of inversion tract lengths from marker data. Application of this method for a number of data sets may help elucidate the relationship between the length of an inversion and the chance that it will get accepted
The Ter-Mikayelian Effect on QCD Radiative Energy Loss
The color dielectric modification of the gluon dispersion relation in a dense
QCD medium suppresses both the soft and collinear gluon radiation associated
with jet production. We compute both the longitudinal and transverse plasmon
contributions to the zeroth order in opacity radiative energy loss. This QCD
analog of the Ter-Mikayelian effect in QED leads to reduction of the
energy loss of high transverse momentum charm quarks produced in a QCD plasma
with a characteristic Debye mass GeV.Comment: 18 Pages, 16 Figure
Prospective, observational practice survey of applied skin care and management of cetuximab-related skin reactions: PROSKIN study.
PURPOSE
The study aimed to investigate strategies to prevent and treat cetuximab-induced skin reactions and their perceived effectiveness in patients with metastatic colorectal cancer (mCRC) and recurrent/metastatic squamous cell cancer of the head and neck (SCCHN).
METHODS
This open-label, prospective observational study was conducted in Switzerland.
RESULTS
A total of 125 patients were included (n = 91 mCRC, n = 34 SCCHN; mean age 63.3 years; 73.6% males). The frequency of acneiform rash grade ≥ 2 increased from 12.6% at week 2 to 21.7% at week 16. The proportion of patients who reported no skin reaction decreased from 75.6% at week 2 to 43.3% at week 16. The most frequently used skin products at any time of observation were moisturizing (77.6%), lipid-regenerating (56.8%) or urea-containing products (52%), systemic antibiotics (49.6%), and vitamin K1 cream (43.2%). There was no clear effectiveness pattern for all product classes: in given patients, either the product showed no effect at all or a moderate/strong effect, consistently over time.
CONCLUSIONS
A great variety of low-cost general skin care products were commonly used. According to physician's preference, systemic antibiotics and vitamin K1 cream are an appropriate approach to prevent or treat cetuximab-related skin toxicity
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