Essential Oils of Three Balkan Abies Species: Chemical Profiles, Antimicrobial Activity and Toxicity toward Artemia salina and Drosophila melanogaster.

This study focused on the essential oils (EOs) isolated from needles with twigs of three indigenous Balkan Abies species (A. alba, A. × borisii-regis and A. cephalonica) regarding their chemical composition, antimicrobial activity and toxicity toward crustaceans and insects. Even though distinct phytochemical profiles of dominant volatiles were revealed for each species, ß-pinene and α-pinene represented the first two major volatiles in all three EOs. Antimicrobial activity of EOs has shown inhibitory effect against all 17 studied strains (ATCC and respiratory isolates) in the range of 0.62-20.00 mg/mL (MICs). Further, all three EOs exhibited strong toxicity (LC50 <100 µg/mL) in Artemia salina lethality bioassay, but with significant differences that depended on the EO type. Additionally, tested EOs have shown a certain level of toxicity against Drosophila melanogaster, mostly at the highest tested concentration (3 %) which caused significant prolongation of developmental time, larvicidal effect and pupal mortality. In the three biological assays performed, there was no observed inhibitory effect or weakest activity for A. alba EO. Further, A. cephalonica EO has shown the highest levels of antimicrobial activity and toxicity toward A. salina, while in relation to the insecticidal potential, A. cephalonica and A. × borisii-regis EOs exhibited similar level of toxicity against D. melanogaster.

The Significance of MGMT Promoter Methylation Status in Diffuse Glioma.

A single-institution observational study with 43 newly diagnosed diffuse gliomas defined the isocitrate dehydrogenase 1 and 2 (IDH1/2) gene mutation status and evaluated the prognostic relevance of the methylation status of the epigenetic marker O6-methylguanine-DNA methyltransferase (MGMT). Younger patients (<50 years) with surgically resected glioma and temozolomide (TMZ) adjuvant chemotherapy were associated with better prognosis, consistent with other studies. The methylation status depends on the chosen method and the cut-off value determination. Methylation-specific PCR (MSP) established the methylation status for 36 glioma patients (19 (52.8%) positively methylated and 17 (47.2%) unmethylated) without relevancy for the overall survival (OS) (p = 0.33). On the other side, real-time methylation-specific PCR (qMSP) revealed 23 tumor samples (54%) that were positively methylated without association with OS (p = 0.15). A combined MSP analysis, which included the homogenous cohort of 24 patients (>50 years with surgical resection and IDH1/2-wildtype diffuse glioma), distinguished 10 (41.6%) methylated samples from 14 (58.4%) unmethylated samples. Finally, significant correlation between OS and methylation status was noticed (p ≈ 0.05). The OS of the hypermethylated group was 9.6 ± 1.77 months, whereas the OS of the unmethylated group was 5.43 ± 1.04 months. Our study recognized the MGMT promoter methylation status as a positive prognostic factor within the described homogenous cohort, although further verification in a larger population of diffuse gliomas is required.

Pseudotsuga menziesii (Pinaceae): Volatile Profiles, Antimicrobial Activity and Toxicological Evaluation of Its Essential Oil.

The present article investigates the chemical composition of volatiles of essential oil (EO) and headspace (HS) fraction, as well as biological activities of EO obtained from needles with twigs of Pseudotsuga menziesii var. menziesii cultivated in Serbia. The major class of compounds was monoterpene hydrocarbons with α-terpinolene, sabinene and ß-pinene (EO), and sabinene, α-terpinolene and ß-pinene (HS) as the dominant volatiles. Tested EO exhibited mostly low antimicrobial potential against investigated strains (ATCC and respiratory isolates), where MICs ranged 1.25-20.00 mg/mL. Nevertheless, based on presented results, where antimicrobial testing was done for the first time on human respiratory system isolates, there is a potential of this EO to be used as an adjuvant in the treatment of human respiratory infections, especially those caused by Pseudomonas aeruginosa or Candida albicans strains. Regarding toxicological evaluation, EO showed moderate toxicity in Artemia salina toxicity bioassay (LC50 =347.41, after 24 h) as well as week toxicity against Drosophila melanogaster with the ability only to moderately delay larval and pupal development.

A Comparison of Six Transport Models of the MADE-1 Experiment Implemented With Different Types of Hydraulic Data.

Six conceptually different transport models were applied to the macrodispersion experiment (MADE)-1 field tracer experiment as a first major attempt for model comparison. The objective was to show that complex mass distributions in heterogeneous aquifers can be predicted without calibration of transport parameters, solely making use of structural and flow data. The models differ in their conceptualization of the heterogeneous aquifer structure, computational complexity, and use of conductivity data obtained from various observation methods (direct push injection logging, DPIL, grain size analysis, pumping tests and flowmeter). They share the same underlying physical transport process of advection by the velocity field solely. Predictive capability is assessed by comparing results to observed longitudinal mass distributions of the MADE-1 experiment. The decreasing mass recovery of the observed plume is attributed to sampling and no physical process like mass transfer is invoked by the models. Measures like peak location and strength are used in comparing the modeled and measured plume mass distribution. Comparison of models reveals that the predictions of the solute plume agree reasonably well with observations, if the models are underlain by a few parameters of close values: mean velocity, a parameter reflecting log-conductivity variability, and a horizontal length scale related to conductivity spatial correlation. The robustness of the results implies that conservative transport models with appropriate conductivity upscaling strategies of various observation data provide reasonable predictions of plumes longitudinal mass distribution, as long as key features are taken into account.

The Impact of MGMT Promoter Methylation and Temozolomide Treatment in Serbian Patients with Primary Glioblastoma.

Background and objective: Despite recent advances in treatment, glioblastoma (GBM) remains the most lethal and aggressive brain tumor. A continuous search for a reliable molecular marker establishes the methylation status of the O6-methylguanine-DNA methyltransferase (MGMT) gene promoter as a key prognostic factor in primary glioblastoma. The aim of our study was to screen Serbian patients with primary glioblastoma for an MGMT promoter hypermethylation and to evaluate its associations with overall survival (OS) and sensitivity to temozolomide (TMZ) treatment. Materials and methods: A cohort of 30 Serbian primary glioblastoma patients treated with radiation therapy and chemotherapy were analyzed for MGMT promoter methylation and correlated with clinical data. Results: MGMT methylation status was determined in 25 out of 30 primary glioblastomas by methylation-specific PCR (MSP). MGMT promoter hypermethylation was detected in 12 out of 25 patients (48%). The level of MGMT promoter methylation did not correlate with patients' gender (p = 0.409), age (p = 0.536), and OS (p = 0.394). Treatment with TMZ significantly prolonged the median survival of a patient (from 5 to 15 months; p < 0.001). Conclusions: Due to a small cohort of primary GBM patients, our study is not sufficient for definitive conclusions regarding the prognostic value of MGMT methylation for the Serbian population. Our preliminary data suggest a lack of association between MGMT promoter methylation and overall survival and a significant correlation of TMZ treatment with overall survival. Further population-based studies are needed to assess the prognostic value of the MGMT promoter methylation status for patients with primary glioblastoma.

Osteogenic potential of in vitro osteo-induced adipose-derived mesenchymal stem cells combined with platelet-rich plasma in an ectopic model.

PURPOSE: The osteogenic potential of in vitro osteo-induced adipose-derived mesenchymal stem cells (ADSCs) combined with platelet-rich plasma (PRP) and implanted on bone mineral matrix (BMM) carrier was examined in a subcutaneous model in Balb/c mice. METHODS: In vitro osteogenic differentiation of ADSCs was monitored by relative bone-related gene expression and osteocalcin expression at the third, seventh and 15th day. Test implants consisting of in vitro osteo-induced ADSCs, PRP and BMM (OPC implants) and control implants consisting of PRP and BMM (PC implants) were examined. The relative expression of the bone-related genes encoding osterix, osteocalcin, collagen type I α1 and alkaline phosphatase was examined in implants extracted at one, two, four and eight weeks. Histochemical, immunohistochemical and histomorphometric analyses of implants extracted at two and eight weeks were performed. RESULTS: The highest relative expression of bone-related genes and osteocalcin expression was found at the 15th day of in vitro osteogenic induction of the ADSCs. Permanent and continuous increased expression of bone-related genes was noticed in OPC implants at eight weeks. Expression peaks of bone-related genes in PC implants were at two and four weeks, but they significantly decreased at eight weeks. The signs of resorption, formation of callus-like tissue positive for osteocalcin and increased presence of bone cells were found in OPC implants compared with PC implants. A higher percentage of infiltrated tissue and vascularisation was found in OPC than in PC implants. CONCLUSIONS: The combination of in vitro osteo-induced ADSCs and PRP on BMM carrier represents a promising approach for bone regeneration.

Superconductivity on the brink of spin-charge order in a doped honeycomb bilayer.

Using a controlled weak-coupling renormalization group approach, we establish the mechanism of unconventional superconductivity in the vicinity of spin or charge ordered excitonic states for the case of electrons on the Bernal stacked bilayer honeycomb lattice. With one electron per site, this system, physically realized in bilayer graphene, is unstable towards a spontaneous symmetry breaking. Repulsive interactions favor excitonic order, such as a charge nematic and/or a layer antiferromagnet. We find that upon adding charge carriers to the system, the excitonic order is suppressed, and unconventional superconductivity appears in its place, before it is replaced by a Fermi liquid. We focus on firmly establishing this phenomenon using the renormalization group formalism within an idealized model with parabolic touching of conduction and valence bands.

Antimicrobial, antioxidative, and insect repellent effects of Artemisia absinthium essential oil.

In this paper, the chemical composition and biological activity of the essential oil of Artemisia absinthium was studied. The aim of this study was to investigate the potential of ethnopharmacological uses of this plant species in the treatment of gastrointestinal diseases and wounds, and as an insect repellent. The aerial part of the plant was hydrodistilled, and the chemical composition of the essential oil was analyzed by gas chromatography and gas chromatography/mass spectrometry. Forty-seven compounds, corresponding to 94.65 % of the total oil, were identified, with the main constituents being sabinene (24.49 %), sabinyl acetate (13.64 %), and α-phellandrene (10.29 %). The oil yield was 0.23 % (v/w). The antimicrobial activity of the oil was investigated against ten bacterial isolates (from patients wounds and stools) and seven American Type Culture Collection strains using a microwell dilution assay. The minimal inhibitory/bactericidal concentration of the oil ranged from < 0.08 to 2.43 mg/mL and from 0.08 to 38.80 mg/mL, respectively. The antioxidant activity of the essential oil was evaluated using 2,2-diphenyl-1-picrylhydrazil and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radical-scavenging methods and assessed as significant. Skin irritation potential and acute toxicity of the oil were also investigated. Results of the skin irritant reaction showed that none of the 30 volunteers developed a positive skin irritant reaction to undiluted A. absinthium essential oil. Acute oral exposure to the essential oil did not cause mortality in the treated mice, but it did cause neurological, muscle, and gastrointestinal problems. A subchronic toxicity test on Drosophila melanogaster showed that the essential oil of A. absinthium is toxic for developing insect larvae. Starting with the concentration of 0.38 % of essential oil in medium, significant mortality of larvae exposed to the oil was noted when compared to the control. Probit analysis revealed that the LC50 value of A. absinthium essential oil for D. melanogaster larvae after 15 days of exposure was 6.31 % (49 mg/mL). The essential oil also affected the development of D. melanogaster larvae and significantly delayed achievement of the pupa stadium.

Serbian Artemisia species - chemical composition, acute toxicity and larvicidal activity of the essential oils.

The chemical composition and biological activities of the essential oils obtained from Serbian Artemisia species (A. alba, A. absinthium, A. annua, A. vulgaris, and A. scoparia) were analysed. The essential oil was obtained by merging several samples (same plant species, different localities) and the chemical composition was compared with pre-merging results. In the merged A. scoparia sample four components were not found in any pre-merging sample and one of those is present in the highest percentage (capillin 35.7%). The least toxic essential oil in Artemia salina test was A. annua, followed by A. alba (both showing medium toxicity), while A. absinthium, A. vulgaris, and A. scoparia showed strong toxicity. All tested samples showed activity against Drosophila melanogaster larvae in descending order ΣAS > ΣAN > ΣAV > ΣAB > ΣAA. The essential oil of A. scoparia has exceptional larvicidal activity (in concentrations of 2% and 1% causes complete mortality).

Evidence Based Estimation of Macrodispersivity for Groundwater Transport Applications.

The scope of this work is to discuss the proper choice of macrodispersion coefficients in modeling contaminant transport through the advection dispersion equation (ADE). It is common to model solute concentrations in transport by groundwater with the aid of the ADE. Spreading is quantified by macrodispersivity coefficients, which are much larger than the laboratory observed pore-scale dispersivities. In the frame of stochastic theory, longitudinal macrodispersivity is related to the hydraulic conductivity spatial variability via its statistical moments (mean, variance, integral scales), which are generally determined by geostatistical analysis of field measurements. In many cases, especially for preliminary assessment of contaminant spreading, these data are not available and ad hoc values are adopted by practitioners. The present study aims at recommending dispersivity values based on a thorough analysis of tens of field experiments. Aquifers are classified as of weak, medium, and high heterogeneity and for each class a range of macrodispersivity values is recommended. Much less data are available for the transverse macrodispersivities, which are significantly smaller than the longitudinal one. Nevertheless, a few realistic values based on field data, are recommended for applications. Transport models using macrodispersivities can predict mean concentrations, different from the local ones. They can be used for estimation of robust measures, like plumes spatial moments, longitudinal mass distribution and breakthrough curves at control planes.

A Comparison of MGMT Testing by MSP and qMSP in Paired Snap-Frozen and Formalin-Fixed Paraffin-Embedded Gliomas.

Comparative analysis of the conventional methylation-specific PCR (MSP) vs. the quantitative MSP (qMSP) assessment of the O6-methylguanine-DNA methyltransferase (MGMT) promoter methylation status in 34 snap-frozen (SF) glioma samples was performed. The accuracy of the semi-quantitative MSP was compared with the corresponding qMSP semi-quantitative values using two semi-quantitative cut-off values (0-unmethylated and 1-weakly methylated) to discriminate methylated from unmethylated samples. In the case of the cut-off value 0, MSP test showed 80.0% sensitivity and 78.9% specificity compared to the reference qMSP analysis. However, when using the cut-off value 1, the diagnostic accuracy of the MSP test was significantly higher (85.7% sensitivity, 85.2% specificity). Fleiss' Kappa statistical analyses indicated moderate agreement (Fleiss' Kappa Coefficient = 0.509; 70.59% agreement) between MSP and qMSP semi-quantitative measurements of MGMT promoter methylation in glioma patients, justifying the conventional MSP use in diagnostics and confirming its high reliability. Further, we aimed to compare the validity of SF and formalin-fixed paraffin-embedded (FFPE) glioma samples for MGMT testing. Statistical analyses indicated moderate overall agreement of FFPE glioma samples and SF MSP semi-quantitative measurements (Fleiss' Kappa Coefficient = 0.516/0.509; 70.0% agreement) and emphasized their low reliability in the assessment of highly methylated MGMT promoter samples.

A Predictive Model of Pandemic Disaster Fear Caused by Coronavirus (COVID-19): Implications for Decision-Makers.

This paper presents quantitative research results regarding a predictive model of pandemic disaster fear caused by the coronavirus disease (COVID-19). The aim of this paper was to establish the level and impact of certain demographic and socioeconomic characteristics on pandemic disaster fear caused by the coronavirus (COVID-19). The research was conducted using a questionnaire that was provided and then collected online for 1226 respondents during May 2021. A closed, five-point Likert scale was used to create the structured questionnaire. The first section of the questionnaire included research questions about the participants' socioeconomic and demographic characteristics, while the second section included issue questions about fear caused by COVID-19. The results of multivariate regression analyses showed the most important predictor for fear of COVID-19 to be gender, followed by age and education level. Furthermore, the results of t-tests showed statistically significant differences between men and women in terms of different aspects of pandemic disaster fear caused by the coronavirus disease. Our results have several significant public health implications. Women who were more educated and knowledgeable, married, and older, reported a greater fear of the outbreak at various levels. Decision-makers can use these findings to identify better strategic opportunities for pandemic disaster risk management.

Antioxidant, antimicrobial and antiproliferative activities of five lichen species.

The antioxidative, antimicrobial and antiproliferative potentials of the methanol extracts of the lichen species Parmelia sulcata, Flavoparmelia caperata, Evernia prunastri, Hypogymnia physodes and Cladonia foliacea were evaluated. The total phenolic content of the tested extracts varied from 78.12 to 141.59 mg of gallic acid equivalent (GA)/g of extract and the total flavonoid content from 20.14 to 44.43 mg of rutin equivalent (Ru)/g of extract. The antioxidant capacities of the lichen extracts were determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals scavenging. Hypogymnia physodes with the highest phenolic content showed the strongest DPPH radical scavenging effect. Further, the antimicrobial potential of the lichen extracts was determined by a microdilution method on 29 microorganisms, including 15 strains of bacteria, 10 species of filamentous fungi and 4 yeast species. A high antimicrobial activity of all the tested extracts was observed with more potent inhibitory effects on the growth of Gram (+) bacteria. The highest antimicrobial activity among lichens was demonstrated by Hypogymnia physodes and Cladonia foliacea. Finally, the antiproliferative activity of the lichen extracts was explored on the colon cancer adenocarcinoma cell line HCT-116 by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) viability assay and acridine orange/ethidium bromide staining. The methanol extracts of Hypogymnia physodes and Cladonia foliacea showed a better cytotoxic activity than the other extracts. All lichen species showed the ability to induce apoptosis of HCT-116 cells.

Capacity Development of Local Self-Governments for Disaster Risk Management.

The objective of this research was to examine the capacity development of local self-governments in the field of disaster risk management (DRM). This quantitative research examines the degree of implementation of strategic, legislative, and institutional frameworks, as well as the capacity of local authorities to apply related policies through five analytical scopes: (1) degree of preparedness and legal framework; (2) financial framework; (3) policy aspects; (4) cooperation and partnership; (5) communication. The ability of municipalities and towns to respond to disasters was also analyzed and compared. In this paper, our initial hypothesis was that the effective implementation of the concept of DRM policy in towns of Serbia requires the continual strategic, tactical, and operational transformation of the public administration and public management system in order to strengthen the capacity of local self-governments for disaster prevention, preparation, response, and recovery. This multimethod research was conducted over the period of 2014-2017 and included the following two target groups: (a) heads of disaster sectors in local self-government units (mayor) and (b) employees of the DRM sector in local self-government units. The results of this research will enable decision makers to successfully respond to challenges and help to improve the capacity of local self-governments and public local administrations within the scope of DRM in the Republic of Serbia, based on the principles of prevention and proactive action, coordination, cooperation, partnership, and responsibility.

Antioxidant Activity of Hemp (Cannabis sativa L.) Seed Oil in Drosophila melanogaster Larvae under Non-Stress and H2O2-Induced Oxidative Stress Conditions.

The oil extracted from hemp seeds has significant nutritional and biological properties due to the unique composition of polyunsaturated fatty acids and various antioxidant compounds. The potential of this oil for the prevention of oxidative stress and for the treatment of oxidative-stress-induced ailments is of increasing interest. Most studies of hemp seed oil were conducted in-vitro, meaning we lack information about effects and activity in vivo. In the present study, we evaluated the hypothesis that hemp seed oil at different concentrations improves the oxidative state of D. melanogaster, under non-stress as well as hydrogen-peroxide-induced stress. We analyzed the effects of hemp seed oil on oxidative stress markers and on the life cycle of D.melanogaster under non-stress and hydrogen-peroxide-induced stress conditions. D.melanogaster larvae were exposed to hemp seed oil concentrations ranging from 12.5 to 125 µL/mL. The results revealed that under non-stress conditions, oil concentrations up to 62.5 µL/mL did not induce negative effects on the life cycle of D. melanogaster and maintained the redox status of the larval cells at similar levels to the control level. Under oxidative stress conditions, biochemical parameters were significantly affected and only two oil concentrations, 18.7 and 31.2 µL/mL, provided protection against hydrogen peroxide stress effects. A higher oil concentration (125 µL/mL) exerted negative effects on the oxidative status and increased larval mortality. The tested oil was characterized chemically by NMR, transesterification, and silylation, followed by GC-MS analyses, and was shown to contain polyunsaturated fatty acid triglycerides and low levels of tocopherols. The high levels of linoleic and linolenic acids in the oil are suggested to be responsible for the observed in vivo antioxidant effects. Taken together, the results show that hemp seed oil is effective for reducing oxidative stress at the cellular level, thus supporting the hypothesis. The obtained results point to the potential of hemp seed oil for the prevention and treatment of conditions caused by the action of reactive oxygen species.

Vascularization and osteogenesis in ectopically implanted bone tissue-engineered constructs with endothelial and osteogenic differentiated adipose-derived stem cells.

BACKGROUND: A major problem in the healing of bone defects is insufficient or absent blood supply within the defect. To overcome this challenging problem, a plethora of approaches within bone tissue engineering have been developed recently. Bearing in mind that the interplay of various diffusible factors released by endothelial cells (ECs) and osteoblasts (OBs) have a pivotal role in bone growth and regeneration and that adjacent ECs and OBs also communicate directly through gap junctions, we set the focus on the simultaneous application of these cell types together with platelet-rich plasma (PRP) as a growth factor reservoir within ectopic bone tissue engineering constructs. AIM: To vascularize and examine osteogenesis in bone tissue engineering constructs enriched with PRP and adipose-derived stem cells (ASCs) induced into ECs and OBs. METHODS: ASCs isolated from adipose tissue, induced in vitro into ECs, OBs or just expanded were used for implant construction as followed: BPEO, endothelial and osteogenic differentiated ASCs with PRP and bone mineral matrix; BPUI, uninduced ASCs with PRP and bone mineral matrix; BC (control), only bone mineral matrix. At 1, 2, 4 and 8 wk after subcutaneous implantation in mice, implants were extracted and endothelial-related and bone-related gene expression were analyzed, while histological analyses were performed after 2 and 8 wk. RESULTS: The percentage of vascularization was significantly higher in BC compared to BPUI and BPEO constructs 2 and 8 wk after implantation. BC had the lowest endothelial-related gene expression, weaker osteocalcin immunoexpression and Spp1 expression compared to BPUI and BPEO. Endothelial-related gene expression and osteocalcin immunoexpression were higher in BPUI compared to BC and BPEO. BPEO had a higher percentage of vascularization compared to BPUI and the highest CD31 immunoexpression among examined constructs. Except Vwf, endothelial-related gene expression in BPEO had a later onset and was upregulated and well-balanced during in vivo incubation that induced late onset of Spp1 expression and pronounced osteocalcin immunoexpression at 2 and 8 wk. Tissue regression was noticed in BPEO constructs after 8 wk. CONCLUSION: Ectopically implanted BPEO constructs had a favorable impact on vascularization and osteogenesis, but tissue regression imposed the need for discovering a more optimal EC/OB ratio prior to considerations for clinical applications.

Tissue response to biphasic calcium phosphate covalently modified with either heparin or hyaluronic acid in a mouse subcutaneous implantation model.

Biphasic calcium phosphate (BCP) materials are widely employed as bone substitute materials due to their resorption/degradation properties. Inflammation after implantation of such materials represents a prerequisite for bone tissue repair and regeneration but can be also problematic if it is not only transient and if it is followed by fibrosis and scarring. Here, we modified BCP covalently with hyaluronan (HA) and heparin (Hep), glycosaminoglycans that possess anti-inflammatory properties. Beside the characterization of particle surface properties, the focus was on in vivo tissue response after subcutaneous implantation in mice. Histological analysis revealed a decrease in signs of inflammatory response to BCP when modified with either HA or Hep. Reduced vascularization after 30 days was noticed when BCP was modified with either HA or Hep with greater cellularity in all examined time points. Compared to plain BCP, expression of endothelial-related genes Flt1 and Vcam1 was higher in BCP-HA and BCP-Hep group at day 30. Expression of osteogenesis-related genes Sp7 and Bglap after 30 days was the highest in BCP group, followed by BCP-Hep, while the lowest expression was in BCP-HA group which correlates with collagen amount. Hence, coating of BCP particles with HA seems to suppress inflammatory response together with formation of new bone-like tissue, while the presence of Hep delays the onset of inflammatory response but permits osteogenesis in this subcutaneous bone-forming model. Transferring the results of this study to other coated materials intended for biomedical application may also pave the way to reduction of inflammation after their implantation.

Changes in the wing shape and size in Drosophila melanogaster treated with food grade titanium dioxide nanoparticles (E171) - A multigenerational study.

Drosophila is among the most commonly used models for toxicity assessment of different types of nanoparticles. This study aims to examine the effects of a constant exposure to the low concentration of human food grade titanium dioxide nanoparticles (TiO2 E171) on Drosophila melanogaster wing morphology over multiple generations. Subsequently, the Geometric Morphometrics Analysis was employed to examine possible changes in the wing shape and size of the treated flies. The treatment resulted in the diminishment but not a disruption in the sexual dimorphism in wings. Consequently, the female flies were clearly separated from the male flies by the differences in wing morphology as in the control group. A splitting by generations was overly similar within the control and the treatment, but it was slightly more pronounced in the treatment. However, the observed generational differences seemed mostly random between generations, irrespective of the treatment. Specifically, the treated groups displayed slightly higher splitting by generations in females than in males. Regardless of the generation, the results show a clear splitting by the differences in the wing shape between the treated flies and the flies from control. The mean value of centroid size, which refers to the wing size, of both female and male wings was smaller in the treatment when compared to the control. The overall effect of TiO2 was to induce significant difference in Drosophila wing morphology but it did not alter the general wing morphology pattern. Therefore, the change in the wings occurred only within the normally allowed wing variation.

Preparedness and Preventive Behaviors for a Pandemic Disaster Caused by COVID-19 in Serbia.

Coronavirus disease 2019 (COVID-19) is an infectious disease caused by severe acute respiratory syndrome coronavirus 2. The disease was first detected in Wuhan, the capital of China's Hubei province, in December 2019 and has since spread globally, especially to Europe and North America, resulting in the ongoing global coronavirus pandemic disaster of 2019-2020. Although most cases have mild symptoms, there is some progression to viral pneumonia and multi-organ failure and death. More than 4.6 million cases have been registered across 216 countries and territories as of 19 April 2020, resulting in more than 311,000 deaths. Risk to communities with continued widespread disease transmission depends on characteristics of the virus, including how well it spreads between people; the severity of resulting illness; and the medical or other measures available to control the impact of the virus (for example, vaccines or medications that can treat the illness) and the relative success of these. In the absence of vaccines or medications, non-pharmaceutical interventions were the most important response strategy based on community interventions such as person-to-person distancing, mask-wearing, isolation and good personal hygiene (hand-washing)-all of which have been demonstrated can reduce the impact of this seemingly unstoppable globally spreading natural disaster. This paper presents the results of quantitative research regarding the level of citizen preparedness for disasters caused by coronavirus disease (COVID-19) in Serbia. The survey was conducted using a questionnaire that was requested and then collected online among 975 respondents during disaster in April 2020. The questionnaire examined citizens' basic socio-economic and demographic characteristics, their knowledge, preparedness, risk perception and preventive measures taken individually and as a community to prevent the death and widespread transmission of novel coronavirus disease 2019 in the Republic of Serbia. Based on the findings that there are major differences in the public's perception of risks posed by communicable disease threats such as presented by COVID-19, emergency management agencies should use these differences to develop targeted strategies to enhance community and national preparedness by promoting behavioral change and improving risk management decision-making.

Phytochemistry, Toxicology and Therapeutic Value of Petasites hybridus Subsp. Ochroleucus (Common Butterbur) from the Balkans.

Petasites hybridus (Common butterbur) is extensively used in traditional medicine, and is currently gaining interest and popularity as a food supplement and for its medicinal properties. It contains a large number of active compounds of potential therapeutic activity, but also toxic pyrrolizidine alkaloids. Science-based information is needed to support the developing modern use of this plant, and to direct continued safe practice in traditional medicine. The present study focused on the essential oils from leaves and rhizomes of the understudied P. hybridus ssp. ochroleucus from the Balkans, and evaluated its phytochemistry and potential therapeutic activities (antimicrobial, antioxidant, anti-cholinesterase and anti-inflammatory), as well its toxicology potential (acute toxicity in insects and mice). We studied the essential oils, which are not commonly used in traditional practices, but have a potential for safe use since the toxic pyrrolizidine alkaloids, which are non-volatiles, are usually not present in the distilled essential oils. Pyrrolizidine alkaloids were indeed not detected in the essential oils; ingestion of the essential oils did not induce toxicity signs in mice, and topical application did not elicit skin irritation in humans. The essential oils had no antimicrobial properties against 20 pathogenic bacterial strains, but demonstrated good local anti-inflammatory activity in a Carrageenan-induced paw edema test. An insect toxicity test demonstrated that the leaf essential oil is an efficient insect repellent, and the demonstrated anti-cholinesterase activity suggests a potential for the treatment of neurological conditions. Isopetasin, a sesquiterpene found in plants of the genus Petasites, known to have anti-inflammatory effects, was present only in the rhizomes essential oil (3.9%), and sesquiterpene lactones concentrations were high, likely contributing to the antioxidant activity.