ZERO ELECTRIC ENERGY ISLAND CONCEPT IN CROATIA – PRELIMINARY STUDY FOR THE ISLAND OF VIS

Hrvatski otoci, s jakim prirodnim potencijalom vjetra i Sunca, moguće su lokacije za intenzivnu uporabu obnovljivih izvora energije. U ovom su radu predstavljeni rezultati preliminarnog istraživanja mogućnosti izvedbe koncepta električno nezavisnog otoka uporabom isključivo 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 klinička, dijagnostička i terapijska obilježja infekcije uzrokovane C. trachomatis u 46 bolesnika novorođenačke i dojenačke dobi, koji su bili hospitalizirani u Klinici za infektivne bolesti od prosinca 1994. do listopada 2005. Prosječna starost kod razbolijevanja bila je sedam tjedana. U 44/46 (95,6 %) djece infekcija je dokazana metodom DNA-RNAhibridizacije, a u preostalih izolacijom na staničnoj kulturi (McCoy). Uzročnik je najčešće dokazan iz aspirata nazofarinksa. U 16/46 (34,8 %) djece dokazana je monoinfekcija klamidijom trahomatis, a u ostalih koinfekcija, najčešće s respiratornim sincicijskim virusom (RSV). Većinom su djeca pri prijamu bila febrilna i imala su simptome respiratornog katara: suhi kašalj, sekreciju iz nosa te injekciju konjunktiva. Petero djece je zbog teškog općeg 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 liječeno azitromicinom, a 19/46 (41,3 %) eritromicinom. Trajanje hospitalizacije u djece liječene azitromicinom je bilo 13,9 dana, a u djece liječene eritromicinom 22,6 dana. Sva su djeca izliječena.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 “an interference reaction" between CRISPR encoded RNA (crRNA) and invader DNA sequences called “protospacers”. Cascade recognizes invader DNA via short “protospacer adjacent motif” (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 “spacers” 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 (Δhns). We present further genetic analyses of the regulation of CRISPR-Cas mediated phage resistance in Δhns E. coli cells. Results: We observed that E. coli Type I-E CRISPR-Cas mediated resistance to phage λ 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 smješten u sekretornim granulama citotoksičkih T-limfocita. Zajedno s ostalim komponentama granula nužan je za lizu stanica organizma inficiranih unutarstaničnim patogenima. Ispitali smo izražaj perforina u citotoksičkim T-limfocitima dojenčadi s bronhiolitisom uzrokovanim respiracijskim sincicijskim virusom (RSV). Uzorci periferne krvi prikupljeni su za vrijeme primarne infekcije i rekonvalescencije u inficirane dojenčadi (n=12) i od kontrolne skupine zdrave djece koja su odgovarala po dobi i spolu. Analiza prikupljenih podataka pokazala je približno jednak postotak citotoksičkih T-limfocita koji izražavaju perforin u sve tri skupine ispitanika. Međutim, pronađene su razlike u razini izražaja perforina po pojedinom limfocitu između rekonvalescentne djece i zdravih kontrola, što upućuje na trajniji poremećaj stanične 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 3′ ending tails toward productive, homologous and away from nonproductive, aberrant recombination events. On the other hand, in recB1080/recB1067 mutants, lacking RecBCD’s 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 3′ 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 3′ 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

ZERO ELECTRIC ENERGY ISLAND CONCEPT IN CROATIA – PRELIMINARY STUDY FOR THE ISLAND OF VIS

Hrvatski otoci, s jakim prirodnim potencijalom vjetra i Sunca, moguće su lokacije za intenzivnu uporabu obnovljivih izvora energije. U ovom su radu predstavljeni rezultati preliminarnog istraživanja mogućnosti izvedbe koncepta električno nezavisnog otoka uporabom isključivo 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

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)