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In this study, mass activity of naturally occurring radioactive materials were measured in twenty-three building material samples, use extensively in the area exposed to a high level of natural background radiation (Mahallat, Iran), to determine the radioactivity index and changes to the level of indoor gamma radiation. The mass activity of 232Th, 226Ra and 40K were within the ranges from 18 ± 3 to 44 ± 10 Bq/kg (average of 27 ± 6 Bq/kg), 22 ± 5 to 53 ± 14 Bq/kg (average of 34 ± 6 Bq/kg) and 82 ± 18 to 428 ± 79 Bq/kg (average of 276 ± 58 Bq/kg), respectively. The gamma dose rates for population were estimated between 48 ± 9 and 111 ± 26 nGy/h with exception of radon exhalation from building materials. Since the air kerma rate in the town varies from 0.8 to 4 μGy/h, the attenuation coefficient was calculated for buildings made of the aforementioned materials. Additionally, the annual gamma radiation doses for inhabitants were calculated based on time spent outdoors and indoors., En este trabajo se ha medido la actividad de materiales NORM en veintitrés muestras de materiales de construcción que se emplean ampliamente en una zona expuesta a niveles elevados de radiación de fondo natural (Mahallat, Irán). El objetivo ha sido determinar el índice de radiactividad y cambios en el nivel de radiación gamma en el interior. Las concentraciones medidas de 232Th, 226Ra, 40K fueron respectivamente (Bq/kg) de 18 ± 3–44 ± 10 (27 ± 6), 22 ± 5–53 ± 14 (34 ± 6), 82 ± 18–428 ± 79 (276 ± 58). Se han estimado unas dosis gamma a la población entre 48 ± 9–111 ± 26 nGy/h a excepción de la exhalación de radón de los materiales de construcción. Dado que la tasa kerma en aire en la ciudad varía entre 0.8–4 μGy/h, se calculó el coeficiente de atenuación para los edificios en los materiales mencionados. Además, las dosis de radiación gamma anual para los habitantes se calcularon teniendo en cuenta el tiempo en interiores y exteriores.

BAckground and aim. The aim of the study was to characterize at molecular genetic level the carbapenem-resistant Enterobacteriaceae strains isolated in Croatia in the frames of the multicenter study. Material and methods. In total 31 carbapenem non-susceptible strains of Enterobacteriaceae were collected during 2011-2012. from five hospital centers located in different geographic regions in Croatia. MICs were performed by microdilution method and interpreted by the EUCAST criteria. The transferability of resistance determinants was tested by conjugation (broth mating method). Investigation of genes encoding for beta lactamases (ESBL, KPC, MBL, OXA-type and plasmidic ampC), plasmid-mediated qunolone resistance determinants (qnrA, qnrB, qnrS, qnrC, qnrD, qepA, aac(6')-Ib-cr variant) was performed by PCR. Strains were typed by PCR-based replicon typing (PBRT) and multi locus sequence typing (MLST). Genotyping of the strains was performed by PFGE. Results. The isolates were uniformly resistant to amoxycillin alone and combined with clavulanate, piperacillin, cefazoline, cefuroxime, ceftazidime, cefotaxime, ceftriaxone, ertapenem, piperacillin/tazobactam and gentamicin but uniformly susceptible to colistin. They were intermedite susceptible or resistant to cefepime, imipenem, meropenem and amikacij. Imipenem resistance was not transferred to E. coli recipient strain. 22 strains harboured VIM MBL most of them (16 stains) were Enterobacter spp, 3 klebsiella spp, and 3 Cibrobacter freundii. Noteworthy, there was a strong correlation between VIM positive strains and qnrB determinant (14 Enterobacter spp and 2 K. pneumoniae). Among the VIM producers the dominant plasmid type was the Inc A/C (17/22) and after Inc L/M (5/22). One K. pneumoniae was KPC-2 producer (ST258). The bla NDM-1 gene was carried by a C.freundii and a K. pneumoniae. These NDM-1 producers coharboured qnrA6 and blaCMY-4 determinants. The VIM and NDM positive isolates also carried blaTEM-1 and blaCTX-M-15 genes and nine were positive for blaCMY and two for blaDHA genes. BlaVIM genes were located in class I integron.Five strains of E. cloacae were clonally related. Conclusions. True carbapenemases emerged in significant number in Croatia from 2011. Carbapenemases found in this study belong to KPC, VIM and NDM family. Investigating of this heterogenic, carbapenem non-susceptible Enterobacteriaceae strains found a strong association between VIM-producers and QNRB determinant in Croatia during 2011-2012.

The present study is aimed to assess the therapeutic potential of sulfonylurea drug glimepiride in comparison with Nerium oleander plant extract on insulin, glucose levels and some liver enzymes activities in streptozotocin-induced diabetic rats. Rats were rendered diabetic by intraperitoneal injection of a single dose of 50 mg kg-1 body weight streptozotocin. Rats with serum glucose levels >200 mg dL-1 were subdivided into three sub-groups: the first sub-group were remained without treatment and considered as diabetics. The second and third subgroups were orally administered 0.1 mg kg-1 body weight/day glimepiride and 250 mg kg-1 body weight/day Nerium oleander, respectively for 4 weeks. Streptozotocin-induced diabetic rats showed hypoinsulinemia and hyperglycemia compared to controls. Strong negative correlation (r = -0.8) was found between serum insulin and glucose levels in diabetic rats. This …

The filamentous hemagglutinin (FHA) of Bordetella pertussis is an adhesin that binds the bacteria to cells of the respiratory epithelium in whooping-cough infections. Mature FHA is a 220 kDa secretory protein that is highly immunogenic and has been included in acellular vaccines. We have investigated its structure by combining electron microscopy and circular dichroism spectroscopy (CD) with computational analysis of its amino acid sequence. The FHA molecule is 50 nm in length and has the shape of a horseshoe nail: it has a globular head that appears to consist of two domains; a 35 nm-long shaft that averages 4 nm in width, but tapers slightly from the head end; and a small, flexible, tail. Mass measurements by scanning transmission electron microscopy establish that FHA is a monomer. Its sequence contains two regions of tandem 19-residue pseudo-repeats: the first, of 38 cycles, starts at residue 344; the second, of 13 cycles, starts at residue 1440. The repeat motifs are predicted to consist of short beta-strands separated by beta-turns, and secondary structure measurements by CD support this prediction. We propose a hairpin model for FHA in which the head is composed of the terminal domains; the shaft consists mainly of the repeat regions conformed as amphipathic, hyper-elongated beta-sheets, with their hydrophobic faces apposed; and the tail is composed of the intervening sequence. Further support for the model was obtained by immuno-labeling electron microscopy. The 19-residue repeats of FHA have features in common with the leucine-rich repeats (LRRs) that are present in many eukaryotic proteins, including some adhesion factors. The model is also compared with the two other classes of filamentous proteins that are rich in beta-structure, i.e. viral adhesins and two beta-helical secretory proteins. Our proposed structure implies how the functionally important adhesion sites and epitopes of FHA are distributed: its tripeptide (RGD) integrin-binding site is assigned to the tail; the putative hemagglutination site forms part of the head; and two classes of immunodominant epitopes are assigned to opposite ends of the molecule. Possible mechanisms are discussed for two modes of FHA-mediated adhesion.