First Report of Watermelon mosaic virus Infecting Melon and Watermelon in Bosnia and Herzegovina.

Hereby the expansion of host range of Watermelon mosaic virus (WMV, Potyvirus, Potyviridae), found previously on zucchini in Bosnia and Herzegovina (3), to two new hosts is reported. Also, this is the first finding of WMV "emerging" (EM) isolate causing more severe symptoms in some cucurbits than "classic" (CL) isolates (1). During a July 2013 survey to determine the presence of WMV on cucurbits in Bosnia and Herzegovina, in the Kosijerovo locality (Laktasi Municipality, Bosnia and Herzegovina), virus-like symptoms were observed on 10% of plants. Severe mosaic, puckering, and leaf deformation as well as necrosis and leaf distortion were observed in a melon (Cucumis melo L.) crop, while mosaic, green vein banding, and leaf curling with reduced leaf size were observed in watermelon (Citrullus lanatus [Thunb.] Matsum and Nakai). Sampled melon and watermelon plants were tested for the presence of WMV with commercial double-antibody sandwich (DAS)-ELISA kit (Bioreba, AG, Reinach, Switzerland). Commercial positive and negative controls were included in each assay. Out of the 30 melon and 25 watermelon plants tested, 24 and 23 samples were positive for WMV, respectively, while no other cucurbit viruses were detected. The virus was mechanically transmitted from one of each of ELISA-positive melon (309-13) and watermelon (314-13) samples to five plants of each Cucurbita pepo 'Ezra F1', C. melo 'Ananas,' and C. lanatus 'Creamson sweet' using 0.01 M phosphate buffer (pH 7). Mild to severe mosaic and bubbling followed by leaf deformation were observed in all inoculated plants 10 to 14 days post-inoculation, regardless the isolate. Serological detection was verified with reverse transcription (RT)-PCR using the One-Step RT-PCR Kit (Qiagen, Hilden, Germany) with primers WMV 5' and WMV 3' (1), designed to amplify a 402- to 408-bp fragment overlapping the N-terminal part of the coat protein (CP) gene. Total RNAs were extracted with the RNeasy Plant Mini Kit (Qiagen). Total RNAs from the Serbian WMV oil pumpkin isolate (GenBank Accession No. JF325890) and RNA from healthy melon and watermelon plants were used as positive and negative controls, respectively. An amplicon of the expected size was produced from all serologically positive melon and watermelon plants, but not from healthy tissues. The RT-PCR products derived from isolates 309-13 and 314-13 were sequenced directly (KJ603311 and KM212956, respectively) and compared with WMV sequences available in GenBank. Sequence analysis revealed 91.5% nucleotide (nt) identity (94.6% amino acid [aa] identity) between the two WMV isolates. The melon WMV isolate shared the highest nt identity of 100% with four WMV isolates from Slovakia (GQ241712 to 13), Serbia (FJ325890), and Bosnia and Herzegovina (KF517099), while the sequence of isolate 314-13 had the highest nt identity with three Serbian isolates (JX262104 to 05 and JX262114) of 99.7% (99.2% aa identity). Phylogenetic analyses placed isolate 309-13 with CL isolates, while isolate 314-13 clustered with EM isolates (1,2). To our knowledge, this is the first report of WMV on melon and watermelon and the first report on EM isolates in Bosnia and Herzegovina. This could cause significant economic losses and become a limiting factor for cucurbit production with the potential of EM isolates to rapidly replace CL (2). References: (1) C. Desbiez et al. Arch. Virol. 152:775, 2007. (2) C. Desbiez et al. Virus Res. 152:775, 2009. (3) V. Trkulja et al. Plant Dis. 98:573, 2014.

Some cosmic radiation dose measurements aboard flights connecting Zagreb Airport.

When primary particles from space, mainly protons, enter the atmosphere, they produce interactions with air nuclei, and cosmic-ray showers are induced. The radiation field at aircraft altitude is complex, with different types of particles, mainly photons, electrons, positrons and neutrons, with a large energy range. The non-neutron component of cosmic radiation dose aboard A320 and ATR40 aircraft was measured with TLD-100 (LiF:Mg,Ti) detectors and the Mini 6100 semiconductor dosimeter; the neutron dose was measured with the neutron dosimeter consisted of LR-115 track detector and boron foil BN-1 or 10B converter. The estimated occupational effective dose for the aircraft crew (A320) working 500 h per year was 1.64 mSv. Another experiment was performed at the flights Zagreb-Paris-Buenos Aires and reversely, when one measured non-neutron cosmic radiation dose; for 26.7 h of flight, the MINI 6100 dosimeter gave an average dose rate of 2.3 microSv/h and the TLD dosimeter registered the dose equivalent of 75 microSv or the average dose rate of 2.7 microSv/h; the neutron dosimeter gave the dose rate of 2.4 microSv/h. In the same month, February 2005, a traveling to Japan (24-h-flight: Zagreb-Frankfurt-Tokyo and reversely) and the TLD-100 measurement showed the average dose rate of 2.4microSv/h; the neutron dosimeter gave the dose rate of 2.5 microSv/h. Comparing dose rates of the non-neutron component (low LET) and the neutron one (high LET) of the radiation field at the aircraft flight level, we could conclude that the neutron component carried about 50% of the total dose, that was near other known data.

Radon anomaly in soil gas as an earthquake precursor.

The mechanical processes of earthquake preparation are always accompanied by deformations; afterwards, the complex short- or long-term precursory phenomena can appear. Anomalies of radon concentrations in soil gas are registered a few weeks or months before many earthquakes. Radon concentrations in soil gas were continuously measured by the LR-115 nuclear track detectors at site A (Osijek) during a 4-year period, as well as by the Barasol semiconductor detector at site B (Kasina) during 2 years. We investigated the influence of the meteorological parameters on the temporal radon variations, and we determined the equation of the multiple regression that enabled the reduction (deconvolution) of the radon variation caused by the barometric pressure, rainfall and temperature. The pre-earthquake radon anomalies at site A indicated 46% of the seismic events, on criterion M>or=3, R<200 km, and 21% at site B. Empirical equations between earthquake magnitude, epicenter distance and precursor time enabled estimation or prediction of an earthquake that will rise at the epicenter distance R from the monitoring site in expecting precursor time T.

Correlating breakage-fusion-bridge events with the overall chromosomal instability and in vitro karyotype evolution in prostate cancer.

Chromosomal instability (CIN) is thought to underlie the generation of chromosomal changes and genomic heterogeneity during prostatic tumorigenesis. The breakage-fusion-bridge (BFB) cycle is one of the CIN mechanisms responsible for characteristic mitotic abnormalities and the occurrence of specific classes of genomic rearrangements. However, there is little detailed information concerning the role of BFB and CIN in generating genomic diversity in prostate cancer. In this study we have used molecular cytogenetic methods and array comparative genomic hybridization analysis (aCGH) of DU145, PC3, LNCaP, 1532T and 1542T to investigate the in vitro role of BFB as a CIN mechanism in karyotype evolution. Analysis of mitotic structures in all five prostate cancer cell lines showed increased frequency of anaphase bridges and nuclear strings. Structurally rearranged dicentric chromosomes were observed in all of the investigated cell lines, and Spectral Karyotyping (SKY) analysis was used to identify the participating rearranged chromosomes. Multicolor banding (mBAND) and aCGH analysis of some of the more complex chromosomal rearrangements and associated amplicons identified inverted duplications, most frequently involving chromosome 8. Chromosomal breakpoint analysis showed there was a higher frequency of rearrangement at centromeric and pericentromeric genomic regions. The distribution of inverted duplications and ladder-like amplifications was mapped by mBAND and by aCGH. Adjacent spacing of focal amplifications and microdeletions were observed, and focal amplification of centromeric and end sequences was present, particularly in the most unstable line DU145. SKY analysis of this line identified chromosome segments fusing with multiple recipient chromosomes (jumping translocations) identifying potential dicentric sources. Telomere free end analysis indicated loss of DNA sequence. Moreover, the cell lines with the shortest telomeres had the most complex karyotypes, suggesting that despite the expression of telomerase, the reduced telomere length could be driving the observed BFB events and elevated levels of CIN in these lines.

Cosmic radiation dose in aircraft--a neutron track etch detector.

Cosmic radiation bombards us at high altitude by ionizing particles. The radiation environment is a complex mixture of charged particles of solar and galactic origin, as well as of secondary particles produced in interaction of the galactic cosmic particles with the nuclei of atmosphere of the Earth. The radiation field at aircraft altitude consists of different types of particles, mainly photons, electrons, positrons and neutrons, with a large energy range. The non-neutron component of cosmic radiation dose aboard ATR 42 and A 320 aircrafts (flight level of 8 and 11 km, respectively) was measured with TLD-100 (LiF:Mg,Ti) detectors and the Mini 6100 semiconductor dosimeter. The estimated occupational effective dose for the aircraft crew (A 320) working 500 h per year was 1.64 mSv. Other experiments, or dose rate measurements with the neutron dosimeter, consisting of LR-115 track detector and boron foil BN-1 or 10B converter, were performed on five intercontinental flights. Comparison of the dose rates of the non-neutron component (low LET) and the neutron one (high LET) of the radiation field at the aircraft flight level showed that the neutron component carried about 50% of the total dose. The dose rate measurements on the flights from the Middle Europe to the South and Middle America, then to Korea and Japan, showed that the flights over or near the equator region carried less dose rate; this was in accordance with the known geomagnetic latitude effect.

Radon in the spas of Croatia.

Radon concentrations in air and geothermal water of the spa pools in Croatia were measured and the average values of 40.3 and 4.5 kBq/m3 were obtained, respectively. Great difference between radon concentrations in pool and spring water was considered as a result of mixing normal and geothermal water in the pool as well as the radon decay. Estimation of an effective dose, received by the personnel in the Bizovac spa, gave the value of 0.27 mSv/y. At the location Stubica, the transfer factor of the radon for air and thermal water in the pool was calculated, and the value of 4.9+/-0.7 x 10(-3) was obtained.

Influence of the recB21 mutation of Escherichia coli K12 on prophage lambda induction.

The inactivation kinetics of the lambda repressor following bleomycin (BM), UV-irradiation and nalidixic acid (NAL) treatments were studied in the recB21 mutant of E. coli K12. The results showed essentially normal induction by UV-irradiation, delayed induction by BM and no induction by NAL. The results were compared with inactivation kinetics in lexA1 and recF143 mutants.

Role of rec genes in SOS-induced inhibition of cell division in Escherichia coli.

The inhibition of cell division induced by bleomycin (BM) and UV irradiation in the set of rec mutants of E. coli K12 was studied. Data presented in this work indicate that BM treatment requires mainly the RecBC pathway for the induction of cell filamentation. In the recB21 mutant cell filamentation is delayed and reduced compared to the wild type. Cell filamentation is BM-induced with similar kinetics in strains with a proficient RecBC recombination pathway (rec+, recF143 and recN262), as well as in the strain with a fully expressed RecF pathway (recB21recC22sbcB15). Induction is completely abolished in the recB21recF143 double mutant. On the other hand cell filamentation was induced similarly by UV irradiation in all strains with a functional recF gene and in the strain with a fully operative RecF pathway, but it was delayed in the recF143 and recB21recF143 mutants.

Radon time variations and deterministic chaos.

Radon concentrations were continuously measured outdoors, in the living room and in the basement at 10 min intervals for a month. Radon time series were analyzed by comparing algorithms to extract phase space dynamical information. The application of fractal methods enabled exploration of the chaotic nature of radon in atmosphere. The computed fractal dimensions, such as the Hurst exponent (H) from the rescaled range analysis, Lyapunov exponent (lambda) and attractor dimension, provided estimates of the degree of chaotic behavior. The obtained low values of the Hurst exponent (0 < H < 0.5) indicated anti-persistent behavior (non-random changes) of the time series, but the positive values of lambda pointed out the grate sensitivity on initial conditions and the deterministic chaos that appeared due to radon time variations. The calculated fractal dimensions of attractors indicated more influencing (meteorological) parameters on radon in the atmosphere.

Thoron activity level and radon measurement by a nuclear track detector.

Radon activity concentrations in the air were measured with LR-115 nuclear track detectors at three locations in Osijek. The respective equilibrium factors and the effective dose equivalents were determined. Indoor concentrations were from 9.8 to 58.2 Bq m-3 and relative errors of the track etching method were near 19 per cent. The indoor alpha potential energy of the radon and thoron progenies was measured with an ISD detector. Independent measurements, performed with a Radhome semiconductor detector, showed that the indoor thoron concentration was nearly 20 per cent of the radon one.

Mapping of cosmic radiation dose in Croatia.

The Earth is continually bombarded by high-energy particles coming from the outer space and the sun. These particles, termed cosmic radiation, interact with nuclei of atmospheric constituents and decrease in intensity with depth in the atmosphere. Measurements of photon and gamma radiation, performed with a Radiameter at 1 m above the ground, indicated dose rates of 50-100 nSv/h. The neutron dose rate was measured with the CR-39 track etch detector calibrated by the CERN-EU high-energy Reference Field (CERF) facility. Correlation between neutron dose rates and altitudes at 36 sites was examined in order to obtain a significant positive correlation coefficient; the resulting linear regression enabled estimation of a neutron dose at particular altitude. The measured neutron dose rate in Osijek (altitude of 89 m, latitude of 45.31° N) was 110 nSv/h.

Measurements of neutron radiation in aircraft.

Radiation environment is a complex mixture of charged particles of the solar and galactic origin, as well as of secondary particles created in an interaction of galactic cosmic particles with the nuclei of the Earth's atmosphere. A radiation field at aircraft altitude consists of different types of particles, mainly photons, electrons, positrons and neutrons, with a large energy range. In order to measure a neutron component of the cosmic radiation, we investigated a few combinations of a track etch detector (CR-39, LR-115) with a plastic converter or boron foil. Detector calibration was performed on neutrons coming from the nuclear reactor, as well as in the CERN-EU high-energy Reference Field (CERF) facility. From November 2007 to September 2008, the neutron dose equivalent was measured by the track detectors during five aircraft flights, in the north geographical latitude from 21° to 58°; the respective average dose rate, determined by using the D-4 detector (CR-39/B), was H(n)=5.9 µSv/h. The photon dose rate, measured by the electronic dosimeter RAD-60 SE, had the average value of H(f)=1.4 µSv/h.

[Epidemiologic characteristics of viral hepatitis. I. Analysis of registered cases of viral hepatitis in Vojvodina]. / Epidemioloske karakteristike virusnih hepatitisa. I. Analiza registrovanih slucajeva virusnih hepatitisa u Vojvodini.

According to reported morbidity rate, viral hepatitis still represents a major epidemiological problem in Voivodina, as well as in the entire country, although some of the epidemiological features of these diseases are changing in the course of time. The present paper contains an analysis of morbidity, changes in the age distribution, the degree of differentiation of the viral hepatitis, participation of hepatitis A and B in the total number of the differentiated cases, as well as their seasonal occurrence.

[Zoonoses in Vojvodina. I. Epidemiologic characteristics of tetanus in Vojvodina]. / Zooantroponoze u Vojvodini. I. Epidemioloske karakteristike tetanusa u Vojvodini.

Epidemiologic characteristics of tetanus in Voivodina were analyzed on the basis of reported cases of sickness or death, during the period from 1962 to 1991, and epidemiologic investigation on 35 sick persons suffering from tetanus during the last 5 years. By compulsory immunization against tetanus this disease is practically eliminated at the age when one is protected by immunity vaccine. Abandoning domiciliary childbirth neonatorum tetanus has been eliminated. Today tetanus occurs sporadically as a result of small, naive injuries, mostly in nonimmunized elderly people. Considering number of the sick, in 6.1% it happens to persons older than 60 years of age. Tetanus remains a health problem because of its high lethality, which is statistically significantly higher in older patients. On the basis of gathered results it is realistic to expect that applying compulsory immunization against tetanus to older people in 10 year intervals will not eliminate this disease, but it will significantly reduce lethality which is still about 25% in Voivodina.

Haemagglutination-inhibiting (HI) antibodies against four prototype strains of influenza A virus in different age groups.

Sera of 197 apparently well persons were tested for residual haemagglutination-inhibiting antibodies against live Hong Kong/68, A/FM/47 and A/PR/34 strains. Sera of 62 well persons, regularly exposed to contacts with swine, were tested against an inactivated A/New Jersey/76 antigen. Those born some time before and during a certain influenza era showed a significantly greater proportion of homologous residual titres against the subtype prevailing in that influenza era, than those born after the termination of the same era. In each of the seven age groups tested both the percentage of positives and the geometric mean titres were usually highest against the Hong Kong strain (representing the most recent era); the next highest were those against the FM1 strain and the lowest were those against the PR8 strain (representing the most distant of these three influenza eras). The serological involvement of donors exposed to regular contacts with swine was relatively stronger against the New Jersey antigen than the response of other serum donors shown against the other three, more recent, prototypes of influenza virus A. The oldest age groups showed significantly lower antibody response against the PR8, FM1 and Hong Kong strains (but not against the New Jersey antigen) than the next one or two of the younger age groups.

Evaluation of assay methods for hepatitis B surface (HBsAg) antigen and its antibody (anti-HBs) in viral hepatitis B (VHB)-HBsAg-positive.

The sensitivity of methods for the detection of HBsAg and its anti-HBs was compared in serial 1200 sera samples from 30 patients with VHB-HBsAg-positive. HBsAg was tested by gel-diffusion (GD), counter-immunoelectrophoresis (CIE), reversed haemogglutination (rHA), redioimmunoassay (RIA), and enzyme immunoassay (EIA). RIA and EIA methods are statistically significantly more sensitive compared with the other methods (P less than 0.0005). By these methods the minimal concentrations of HBsAg in sera can be proved. Although there is no statistically significant difference in the sensitivity between RIA and EIA, the latter is more sensitive if the subtype ay-HBsAg is considered (12 sera samples). In 24 patients the subtype was ay, in two ad, and in four it could not be differentiated. In 70% of patients anti-HBs was proved by RIA and in 10% by CIE, i.e., in 73% and 9% of sera samples, respectively. In 117 sera samples of these patients the sensitivity of RIA and EIA was compared for determination of anti-HBs. No statistically significant difference between the methods for determination of anti-HBs was found (50.42%: 40.17%). No immune response to HBsAg has been observed in 9 cases, but 6 of them have remained permanent carriers of this antigen.

Serological studies of Australia-antigenaemia in different categories of sick and healthy persons.

Sera (1,333) were collected from patients at various days after the onset of manifest B-virus hepatitis; from long term asymptomatic carriers of Au-antigen, with or without a demonstrable history of hepatitis; and from apparently healthy Au-negative persons. Au-anti-genaemia was tested with gel-diffusion (GD), counter immunoelectrophoresis (CIE), reversed haemagglutination (RHA) and complement fixation (CF). The CF test was found to be as sensitive as the RHA test, about 10 times more sensitive than the CIE, and about 25 times more sensitive than the GD test. With greater amounts of antibodies used in CF tests, the titres of AU-antigen were higher and the heights of prozones were lower. It is stressed that in screening for Au-antigen, sera should be tested in dilutions from 2 to 64, against 4 to 8 CF units of antibody. The frequency of asymptomatic long term Au-carriers, in the group with a known history of hepatitis, amounted to 41%, and themean titre of Au-antigen was 1:392. In the group of long-term carriers with no detectable history of hepatitis, the rate of Au-carriers was 1.6%, and the mean titre was 1:19.