ZAGAĐENJE TLA POLICIKLIČKIM AROMATSKIM UGLJIKOVODICIMA NA PODRUČJU GRADA LABINA KAO POSLJEDICA RUDARENJA RAŠKOGA UGLJENA I SRODNIH INDUSTRIJSKIH DJELATNOSTI

The aim of this study was to determine the mass fraction of polycyclic aromatic hydrocarbons (PAHs) in the soil of the Labin city area (west Croatia) as a consequence of the pollution caused by centuries old Raša coal mining and associated metal processing and foundry industries. Samples of topsoil down to 10-cm depth, following the removal of plant cover, were collected, air-dried, and sieved to <2 mm. Afterwards, they were extracted, and PAH levels were measured by high performance liquid chromatography using a fluorescence detector with a varying wavelength of excitation and emission (HPLC/FLD). The results showed substantially elevated levels of PAHs across the study area. The soil pollution with PAHs increased in the direction towards the Raša Bay, where a former coal separation unit was in operation decades ago. The results demonstrated the presence of pyrolitic PAHs that resulted from Raša coal combustion at high temperatures in power plants, and unburnt coal-derived PAHs formed by Raša coal carbonization. This paper for the first time reports levels of PAHs in soil of the Labin city area, establishing them as higher than the values set by Croatian legislation. Therefore, this study clearly calls for immediate clean-up measures in order to solve the environmental pollution issue of the vulnerable local karst area.Cilj ovoga istraživanja bio je utvrditi maseni udio policikličkih aromatskih ugljikovodika (PAU) u tlu na području grada Labina (zapadna Hrvatska) kao posljedicu onečišćenja uzrokovanoga stoljetnim iskapanjem raškoga ugljena te srodnim metaloprerađivačkim i ljevaoničkim industrijskim djelatnostima. Prikupljeni su uzorci gornjega sloja tla (do 10 cm dubine) nakon uklanjanja biljnoga pokrova, osušeni na zraku i prosijani kroz sito < 2 mm. Nakon toga su ekstrahirani, a razine PAU-a mjerene su tekućinskom kromatografijom visoke djelotvornosti s fluorescentim detektorom promjenjivih valnih duljina ekscitacije i emisije (HPLC/FLD). Rezultati su pokazali znatno povišene razine PAU-a u istraživanome području. Zagađenje tla PAU-ima raste u smjeru prema Raškome zaljevu, gdje je do prije nekoliko desetljeća radila bivša jedinica za odvajanje ugljena. Rezultati pokazuju prisutnost pirolitičkih PAU-a nastalih izgaranjem raškoga ugljena na visokim temperaturama u elektranama te nesagorjelih PAU-a iz ugljena dobivenih karbonizacijom toga ugljena. Ovo je prvi znanstveni rad koji prikazuje razine PAU-a u tlu na području grada Labina, pronalazeći da one premašuju vrijednosti utvrđene hrvatskim zakonodavstvom. Stoga je ovo istraživanje jasan dokaz da su na tome području potrebne hitne mjere čišćenja (remedijacije) kako bi se riješilo pitanje onečišćenja lokalnoga osjetljivoga krškog okoliša

RECOMMENDATIONS FOR PERIOPERATIVE FASTING IN CHILDREN

Perioperacijsko gladovanje standardni je postupak pripreme bolesnika za kirurške zahvate. Aktualne smjernice za perioperacijsko gladovanje u djece preporučuju pridržavanje upute „2-4-6“, tj. uzimanje bistre tekućine do 2 sata, majčina mlijeka do 4 sata, a ostalih nehumanih mlijeka i krute hrane do 6 sati prije kirurškog zahvata. Oralno uzimanje tekućine dopušteno je u prva 3 poslijeoperacijska sata u većine pedijatrijskih bolesnika. Predugo perioperacijsko gladovanje nije preporučljivo, a može biti i štetno, i za zdravu djecu i za posebne skupine pedijatrijskih bolesnika poput onkoloških. Primjerenim planiranjem operacijskog programa, dobrom koordinacijom anesteziološkog i kirurškog tima te pridržavanjem naputaka iz smjernica mogu se izbjeći neželjeni učinci predugoga perioperacijskoga gladovanja. Iako novija istraživanja upućuju na prednost liberalnijega perioperacijskog pristupa od onog u aktualnim smjernicama u djece, za sada nema dovoljno dokaza za promjenu postojećih preporuka. No, sudeći prema istraživanjima koja se provode, moguće je da će ubrzo biti prikupljeni dokazi u prilog dodatnom skraćivanju vremena perioperacijskoga gladovanja.Perioperative fasting is a standard procedure for the preparation of patients for surgery. The current guidelines for perioperative fasting in children recommend adherence to the instructions, “2-4-6” i.e. taking clear liquids up to 2 hours, breast milk up to 4 hours, and other non-human milk and solids up to 6 hours prior to surgery. Oral fluid intake is allowed within the first 3 postoperative hours in most pediatric patients. Too long perioperative fasting is not recommended, and may be harmful, both for healthy children so for a specific group of pediatric patients such as cancer patients. It is possible to avoid the adverse effects of prolonged perioperative fasting by appropriate planning of operating programs, good coordination of anesthetic and surgical team and compliance to the guidelines. Although recent studies suggest an advantage of more liberal perioperative approach in relation to the current guidelines in children, for now there is no enough evidence to change existing recommendations. However, according to ongoing studies it is possible that soon there will be evidence enough to support additional shortening of perioperative fasting time interval

Juvenile Myelomonocytic Leukemia with PTPN11 Mutation in a 23-Month-Old Girl

Juvenile myelomonocytic leukemia (JMML) is a rare clonal myeloproliferative disorder affecting young children. The natural course of JMML is rapidly fatal with 80% of patients surviving less than three years. Allogeneic hematopoietic stem cell transplantation (HSCT) is the only curative treatment of JMML. We report a case of a 23-month-old girl who presented with an upper respiratory tract infection, fever, rash, diarrhea, hepatosplenomegaly and abdominal distention. Severe elevation of white blood cell count with monocytosis and myeloid progenitors in the peripheral blood was also detected. Bone marrow smear showed morphology suggestive of JMML, an unspecific immune phenotype and a normal karyotype. DNA analysis revealed a mutation in the PTPN11 gene. Therefore, the final diagnosis of JMML with somatic PTPN11 mutation was established. Following three months of cytostatic therapy with 6-mercaptopurine and low doses of cytarabine partial remission was achieved and allogeneic HSCT was successfully performed. Six months after the diagnosis, the girl was in a good condition and in a complete remission of JMML. Early diagnosis and allogeneic HSCT were crucial for successful treatment outcome

Application of microbial levan as a new component for production of graft copolymer with polystyrene

Polysaccharides based on fructose, also called fructans, are synthetized from sucrose by some plant species and many bacteria, fungi and Archaea. Levan is an exopolysaccharide composed of fructose units and has numerous applications in personal care and cosmetics, medicine and food industry. Polystyrene is the most widespread polymer for plastic production due to its low costing and easy production. Degradation of polystyrene is longterm process, therefore incorporating natural polymers is the desirable approach. In the present study, levan-polystyrene graft copolymer (L-g-PS) was synthetized, characterized and influence of reaction time on grafting reaction at two temperatures was investigated. Levan was isolated after cultivation Bacillus licheniformis NS032. Syntheses of L-g-PS were performed by the free radical reaction using K2S2O8 as initiator. Grafting reactions proceeded in nitrogen atmosphere, at 55ºC and 70ºC and reaction time ranged between 15 and 210 min. FTIR spectra and XRD patterns were recorded using a Thermo Nicolet 6700 Spectrophotometer and Philips PW-1710 automated diffractometer, respectively. The formation of L-d-g-PS was confirmed by FTIR spectra which displayed the presence of all characteristic peaks for both component and X-ray diffractograms which showed amorphous nature of copolymer. Compared to other reaction parameters, the temperature of 70ºC and time of 45 min was more optimal showing higher percentage of grafting

Pre-B-cell acute lymphoblastic leukemia with bulk extramedullary disease and chromosome 22 (EWSR1) rearrangement masquerading as Ewing sarcoma

We report a 2-year-old female with a subcutaneous tumor who was initially misdiagnosed as suffering from Ewing sarcoma with a positive EWSR1 rearrangement and EWS/FLI1 transcript. After finding lymphoblasts in peripheral blood, the diagnosis of acute lymphoblastic leukemia was established. This necessitated further analysis of the subcutaneous tumor. The tissue was positive for immature B-cell markers and an immunoglobulin heavy chain gene rearrangement, which confirmed the final diagnosis of common type acute lymphoblastic leukemia with bulk extramedullary disease. The patient was treated with chemotherapy and was in remission 30 months after the diagnosis

Relationship Between Tumor Vascularity and Vascular Endothelial Growth Factor as Prognostic Factors for Patients with Neuroblastoma

Although the role of angiogenesis in tumor progression and response to treatment is generally well-characterized, for neuroblastomas clinical data regarding the contribution of angiogenesis and its predictive capacity remain unclear. The aim of this study was to evaluate whether tumor vascularity in the combination with expression of vascular endothelial growth factor (VEGF) represent prognostic factors for patients with neuroblastoma. Immunohistochemistry using anti- -CD34 and anti-VEGF antibodies was used to analyze paraffin-embedded primary tumor tissues from 56 patients diagnosed with neuroblastoma. Tumor vascularity was estimated by calculating the tumor vascular volume fraction (TVVF), and VEGF expression was determined using semi-quantitative scoring. Statistical analyses including multivariate analysis were performed and compared with these two factors. Tumor vascularity had impact on survival of high VEGF expression neuroblastoma patients. Combination of high VEGF expression and TVVF value 5% was independent predictor of overall survival (p-value =0.0041, odds ratio (OR) (95%CI)=8.67 (1.99–37.69) by the Cox proportional hazards model). This study revealed for the first time a group of extremely high-risk neuroblastoma with both high VEGF expression and poor vascularity. For these patients reduced rates of survival were observed (37% vs. 92.5%) (p<0.0001). These patients did not experience a significant improvement following hematopoietic stem cell transplantation, and could be candidates for receiving novel therapies. These results indicate the importance of the mutual relationship between tumor vascularity and VEGF, because it gives better insight into the prognosis of patients with neuroblastoma

Assisted phytostabilization of Pb-contaminated soil using brushite-metakaoiln geopolymer materials and Festuca rubra

Lead (Pb) is one of the most common environmental pollutants and high concentrations of this element can cause numerous symptoms of phytotoxicity. Inorganic amendments immobilize metal/metalloid ions and reduce their bioavailability in the soil by increasing pH or by adsorbing them. Adsorption mechanisms include chemical precipitation, ion exchange, and crystal growth. In this experiment, geopolymer materials were newly synthesized from a natural raw kaolinite clay with 2, 4, and 6 wt % (GPB2, GPB4, and GPB6) of pure brushite addition. Previous research has shown that brushite-metakaolin geopolymer materials can be successfully synthesized and that they have significant efficiency in removing lead ions from aqueous solutions. Plant samples were grown under controlled conditions in eight different series using commercial substrate and seeds. Four series contained lead-contaminated soil and were treated with brushite-metakaolin geopolymer materials, while the other four series, which contained uncontaminated soil, were also treated with brushite-metakaolin geopolymer materials and served as control series. The plant samples were taken after six weeks. Lead concentrations in the different plant and soil samples were analyzed using an absorption spectrophotometer (AAS). BCF, BAF and TF were calculated from the results obtained. Moreover, physiological and biochemical experiments were carried out and total antioxidant capacity, total phenols, free proline and photosynthetic pigments (chlorophyll a, chlorophyll b, and carotenoids) contents were measured in different plant samples. The results show different responses to metal/metalloid toxicity in the control and treated plant samples, confirming that there is a significant influence of brushite-metakaolin geopolymer materials on the phytostabilization efficiency of Festuca rubra. Phytostabilization is an ecofriendly and cost-effective technique that allows the metals/metalloids to be immobilized in the soil by plants, preventing their migration into the surrounding ecosystem and reducing the chances of them entering the food chain.Twenty-First Young Researchers’ Conference - Materials Science and Engineering: Program and the Book of Abstracts; November 29 – December 1, 2023, Belgrade, Serbi

Termalna stabilnost konjugata polienskog antibiotika sa polisaharidom

Poster: [https://cer.ihtm.bg.ac.rs/handle/123456789/5057