12 research outputs found
ZERO ELECTRIC ENERGY ISLAND CONCEPT IN CROATIA ā PRELIMINARY STUDY FOR THE ISLAND OF VIS
Hrvatski otoci, s jakim prirodnim potencijalom vjetra i Sunca, moguÄe su lokacije
za intenzivnu uporabu obnovljivih izvora energije. U ovom su radu predstavljeni
rezultati preliminarnog istraživanja moguÄnosti izvedbe koncepta elektriÄno
nezavisnog otoka uporabom iskljuÄivo obnovljivih izvora energije. Istraživanje je
provedeno za otok Vis.Croatian islands, with strong natural wind and solar potential, are possible
locations for extensive usage of renewable energy sources. This paper presents
the results of the preliminary investigation of the applicability of renewable
energy sources for the zero-energy island concept on Croatian islands, in
particular for the central Dalmatian island of Vis
Respiratory tract infections caused by Chlamydia trachomatis in newborns and infants
Retrospektivno smo analizirali kliniÄka, dijagnostiÄka i terapijska obilježja infekcije uzrokovane C. trachomatis u 46 bolesnika novoroÄenaÄke i dojenaÄke dobi, koji su bili hospitalizirani u Klinici za infektivne bolesti od prosinca 1994. do listopada 2005. ProsjeÄna starost kod razbolijevanja bila je sedam tjedana. U 44/46 (95,6 %) djece infekcija je dokazana metodom DNA-RNAhibridizacije, a u preostalih izolacijom na staniÄnoj kulturi (McCoy). UzroÄnik je najÄeÅ”Äe dokazan iz aspirata nazofarinksa. U 16/46 (34,8 %) djece dokazana je monoinfekcija klamidijom trahomatis, a u ostalih koinfekcija, najÄeÅ”Äe s respiratornim sincicijskim virusom (RSV). VeÄinom su djeca pri prijamu bila febrilna i imala su simptome respiratornog katara: suhi kaÅ”alj, sekreciju iz nosa te injekciju konjunktiva. Petero djece je zbog teÅ”kog opÄeg stanja strojno ventilirano. S obzirom na laboratorijska obilježja, 4/16 (25,0 %) djece s monoinfekcijom imalo je eozinofiliju, a 13/16 (81,3 %) hipergamaglobulinemiju. 27/46 (58,7 %) djece je lijeÄeno azitromicinom, a 19/46 (41,3 %) eritromicinom. Trajanje hospitalizacije u djece lijeÄene azitromicinom je bilo 13,9 dana, a u djece lijeÄene eritromicinom 22,6 dana. Sva su djeca izlijeÄena.We retrospectively analyzed clinical, diagnostic and therapeutic characteristics of Chlamyda trachomatis infection in 46 newborns and infants hospitalized at the University Hospital for Infectious Diseases Zagreb between December 1994 and October 2005. The median age of patients was seven weeks. In 44/46 (95.6 %) children Chlamydia was demonstrated by using the DNA-RNA hybridisation method, and in the remaining by cell culture (McCoy). Chlamydia was mostly isolated from a nasal aspirate. Altogether 16/46 (34.7 %) children had Chlamyda trachomatis monoinfection and the rest had a co-infection, mostly with RSV. On admission, the majority of children were febrile and had the following respiratory symptoms: dry cough, nasal secretion and conjunctival infection. Because of poor general condition, five patients were mechanically ventilated. Concerning laboratory characteristics, 4/16 (25.0 %) children with monoinfection had eosinophilia, and 13/16 (81.3 %) hypergammaglobulinaemia. In total, 27/46 (58.7 %) children were treated with azithromycin, and 19/46 (41.3 %) with erythromycin. The children treated with azithromycin were hospitalized for 13.9 days, and the children treated with erythromycin for 22.6 days. All children recovered successfully
The decay Z -> neutrino antineutrino photon in the Standard Model
A complete study of the one-loop induced decay Z -> neutrino antineutrino
photon is presented within the framework of the Standard Model. The advantages
of using a nonlinear gauge are stressed. We have found that the main
contributions come from the electric dipole and the magnetic dipole transitions
of the Z gauge boson and the neutrino, respectively. We obtain a branching
ratio B=7.16E-10, which is about four orders of magnitude smaller than the
bound recentely obtained by the L3 collaboration and thus it leaves open a
window to search for new physics effects in single-photon decays of the Z
boson.Comment: REVTEX,15 pp, 5 eps figures, Approved for publication in Physical
Review
Cas3 is a limiting factor for CRISPR-Cas immunity in Escherichia coli cells lacking H-NS
Background: CRISPR-Cas systems provide adaptive immunity to mobile genetic elements in prokaryotes. In many bacteria, including E. coli, a specialized ribonucleoprotein complex called Cascade enacts immunity by āan interference reaction" between CRISPR encoded RNA (crRNA) and invader DNA sequences called āprotospacersā. Cascade recognizes invader DNA via short āprotospacer adjacent motifā (PAM) sequences and crRNA-DNA complementarity. This triggers degradation of invader DNA by Cas3 protein and in some circumstances stimulates capture of new invader DNA protospacers for incorporation into CRISPR as āspacersā by Cas1 and Cas2 proteins, thus enhancing immunity. Co-expression of Cascade, Cas3 and crRNA is effective at giving E. coli cells resistance to phage lysis, if a transcriptional repressor of Cascade and CRISPR, H-NS, is inactivated (Īhns). We present further genetic analyses of the regulation of CRISPR-Cas mediated phage resistance in Īhns E. coli cells.
Results: We observed that E. coli Type I-E CRISPR-Cas mediated resistance to phage Ī» was strongly temperature dependent, when repeating previously published experimental procedures. Further genetic analyses highlighted the importance of culture conditions for controlling the extent of CRISPR immunity in E. coli. These data identified that expression levels of cas3 is an important limiting factor for successful resistance to phage. Significantly, we describe the new identification that cas3 is also under transcriptional control by H-NS but that this is exerted only in stationary phase cells.
Conclusions: Regulation of cas3 is responsive to phase of growth, and to growth temperature in E. coli, impacting on the efficacy of CRISPR-Cas immunity in these experimental systems
Perforin expression in cytotoxic Tcells of infants with respiratory syncytial virus bronchiolitis
Perforin je protein smjeÅ”ten u sekretornim granulama citotoksiÄkih T-limfocita. Zajedno s ostalim komponentama granula nužan je za lizu stanica organizma inficiranih unutarstaniÄnim patogenima. Ispitali smo izražaj perforina u citotoksiÄkim T-limfocitima dojenÄadi s bronhiolitisom uzrokovanim respiracijskim sincicijskim virusom (RSV). Uzorci periferne krvi prikupljeni su za vrijeme primarne infekcije i rekonvalescencije u inficirane dojenÄadi (n=12) i od kontrolne skupine zdrave djece koja su odgovarala po dobi i spolu. Analiza prikupljenih podataka pokazala je približno jednak postotak citotoksiÄkih T-limfocita koji izražavaju perforin u sve tri skupine ispitanika. MeÄutim, pronaÄene su razlike u razini izražaja perforina po pojedinom limfocitu izmeÄu rekonvalescentne djece i zdravih kontrola, Å”to upuÄuje na trajniji poremeÄaj staniÄne imunosti nakon prestanka infekcije RSV-om.Perforin is a protein located in secretory granules of cytotoxic T cells. Together with other granules\u27 proteins perforin is necessary for lysis of host\u27s cells infected with intracellular pathogens. We investigated peforin expression in cytotoxic T cells of infants with bronchiolitis caused by respiratory syncytial virus (RSV). The peripheral blood samples were obtained from hospitalized infants during primary infection and after the resolution of the disease (n=12), and from the control group of age- and gender-matched healthy children. Analysis of the data revealed that the percentage of perforin-expressing cytotoxic T cells was similar in all three groups of tested subjects. However, there were differences in perforin expression levels in cytotoxic T cells between once-infected infants and their healthy controls. This indicates an ongoing disturbed cellular immune response even after the resolution of RSV infection
DNA End Resection Controls the Balance between Homologous and Illegitimate Recombination in Escherichia coli
Even a partial loss of function of human RecQ helicase analogs causes adverse effects such as a cancer-prone Werner, Bloom or Rothmund-Thompson syndrome, whereas a complete RecQ deficiency in Escherichia coli is not deleterious for a cell. We show that this puzzling difference is due to different mechanisms of DNA double strand break (DSB) resection in E. coli and humans. Coupled helicase and RecA loading activities of RecBCD enzyme, which is found exclusively in bacteria, are shown to be responsible for channeling recombinogenic 3ā² ending tails toward productive, homologous and away from nonproductive, aberrant recombination events. On the other hand, in recB1080/recB1067 mutants, lacking RecBCDās RecA loading activity while preserving its helicase activity, DSB resection is mechanistically more alike that in eukaryotes (by its uncoupling from a recombinase polymerization step), and remarkably, the role of RecQ also becomes akin of its eukaryotic counterparts in a way of promoting homologous and suppressing illegitimate recombination. The sickly phenotype of recB1080 recQ mutant was further exacerbated by inactivation of an exonuclease I, which degrades the unwound 3ā² tail. The respective recB1080 recQ xonA mutant showed poor viability, DNA repair and homologous recombination deficiency, and very increased illegitimate recombination. These findings demonstrate that the metabolism of the 3ā² ending overhang is a decisive factor in tuning the balance of homologous and illegitimate recombination in E. coli, thus highlighting the importance of regulating DSB resection for preserving genome integrity. recB mutants used in this study, showing pronounced RecQ helicase and exonuclease I dependence, make up a suitable model system for studying mechanisms of DSB resection in bacteria. Also, these mutants might be useful for investigating functions of the conserved RecQ helicase family members, and congruently serve as a simpler, more defined model system for human oncogenesis
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Cas1-Cas2 physically and functionally interacts with DnaK to modulate CRISPR Adaptation
Data Availability: The data underlying this article are available in the article and in its online supplementary material....BBSRC grant number BB/T006625-1 (ELB) and BB/T007168/1 (CJR); Croatian Science Foundation grant IP-2016-06-8861 (IIB)