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1.
Polymers (Basel) ; 14(7)2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35406169

RESUMO

The plasticizers used in this study were synthesized from renewable raw materials using succinic acid, oleic acid, and propylene glycol. Four environmentally friendly plasticizer samples were obtained; their chemical structures and compositions were confirmed by gas chromatography (GC) and infrared spectroscopy (FT-IR) analyses, and their physicochemical properties and thermal stability (TGA analysis) were investigated. The obtained ester mixtures were used as poly(vinyl chloride) (PVC) plasticizers and their plasticization efficiency was determined in comparison to traditional, commercially available phthalate plasticizers, such as DEHP (di(2-ethylhexyl phthalate) and DINP (diisononyl phthalate). Mechanical properties and migration resistance were determined for soft PVC with the use of three concentrations of plasticizers (40 PHR, 50 PHR, and 60 PHR). It was observed that the obtained plasticizers exhibited the same plasticization efficiency and were characterized with good mechanical and physical properties in comparison to commercial plasticizers. The tensile strength was approx. 19 MPa, while the elongation at break was approx. 250% for all tested plasticizers at a concentration of 50 PHR. Furthermore, plasticizer migration studies showed that the synthesized plasticizers had excellent resistance to plasticizer leaching. The best migration test result obtained was 70% lower than that for DEHP or DINP. The ester mixture that was found to be the most favorable plasticizer was characterized by good thermal and thermo-oxidative stability (5% weight loss temperature: 227.8 °C in air and 261.1 °C in nitrogen). The results of the research clearly indicate that the synthesized esters can provide a green alternative to toxic phthalate plasticizers.

2.
Biomed Res Int ; 2020: 1648264, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32099842

RESUMO

The increase in type 1 diabetes mellitus (T1DM) incidence in children is worrying and not yet fully explored. It is suggested that probably air pollution exposure could contribute to the development of T1DM. The aim of the study was to investigate the relationship between the concentration of gaseous pollutants including, nitrogen dioxide (NO2), nitric oxides (NOx), sulphur dioxide (SO2), carbon monoxide (CO), and particulate matter (PM) in the air, and the number of new cases of T1DM in children. The number of new cases of T1DM was obtained from the Clinic of Paediatrics, Diabetology, and Endocrinology, Medical University of Gdansk. The number of children of 0-18 years old in Pomeranian Voivodeship was acquired from the Statistical Yearbook. The concentrations of PM10 absorbance, NO2, NOx, SO2, and CO were measured at 41 measuring posts, between 1 January 2015 and 31 December 2016. It was detected that the average annual concentration of PM10 was higher than the value acceptable to the WHO. Furthermore, the average 24-hour concentration of PM10 was 92 µg/m3 and was higher compared to the acceptable value of 50 µg/m3 (acc. to EU and WHO). Moreover, the number of new cases of T1DM showed a correlation with the annual average concentration of PM10 (ß = 2.396, p < 0.001), SO2 (ß = 2.294, p < 0.001), and CO (ß = 2.452, p < 0.001). High exposure to gaseous pollutants and particulate matter in ambient air may be one of the factors contributing to the risk of developing T1DM in children. Therefore, it is important to take action to decrease air pollutant emissions in Poland. It is crucial to gradually but consistently eliminate the use of solid fuels, such as coal and wood in households, in favour of natural gas and electricity. The development of new technologies to improve air quality, such as "best available techniques" (BAT) or renewable energy sources (water, wind, and solar generation) is of critical importance as well.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Diabetes Mellitus Tipo 1/epidemiologia , Exposição Ambiental/efeitos adversos , Material Particulado/administração & dosagem , Adolescente , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/etiologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Polônia/epidemiologia
3.
Artigo em Inglês | MEDLINE | ID: mdl-31661892

RESUMO

Acute kidney injury (AKI) is described as a relatively common complication of exercise. In clinical practice the diagnosis of AKI is based on serum creatinine, the level of which is dependent not only on glomerular filtration rate but also on muscle mass and injury. Therefore, the diagnosis of AKI is overestimated after physical exercise. The aim of this study was to determine changes in uremic toxins: creatinine, urea, uric acid, asymmetric dimethylarginine (ADMA), symmetric dimethylarginine (SDMA), trimethylamine N-oxide (TMAO) and urinary makers of AKI: albumin, neutrophil gelatinase-associated lipocalin (uNGAL), kidney injury molecule-1 and cystatin-C (uCyst-C) after long runs. Sixteen runners, mean age 36.7 ± 8.2 years, (2 women, 14 men) participating in 10- and 100-km races were studied. Blood and urine were taken before and after the races to assess markers of AKI. A statistically significant increase in creatinine, urea, uric acid, SDMA and all studied urinary AKI markers was observed. TMAO and ADMA levels did not change. The changes in studied markers seem to be a physiological reaction, because they were observed almost in every runner. The diagnosis of kidney failure after exercise is challenging. The most valuable novel markers which can help in post-exercise AKI diagnosis are uCyst-C and uNGAL.


Assuntos
Injúria Renal Aguda/urina , Corrida/fisiologia , Proteínas de Fase Aguda , Adulto , Albuminúria , Arginina/análogos & derivados , Arginina/sangue , Biomarcadores , Creatinina/sangue , Feminino , Taxa de Filtração Glomerular , Humanos , Lipocalina-2/urina , Lipocalinas , Masculino , Metilaminas/sangue , Pessoa de Meia-Idade , Ureia/sangue , Ácido Úrico/sangue , Água
4.
Infect Drug Resist ; 12: 2323-2334, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31534351

RESUMO

Aim: The aim of the study was to investigate the relationship between the concentration of psychrophilic bacteria, mesophilic bacteria and mold fungi in bioaerosols, and the number of new cases of type 1 diabetes mellitus (T1DM) in children. Methods: Air samples from the Lubelskie and Pomeranian voivodeships in Poland were collected from January 2015 to December 2016 in winter, spring, summer and autumn. Thirty-three samples were collected in the Pomeranian and 27 in the Lubelskie voivodeship. The air samples were collected on the first day of each month at 1:00 pm for 10 mins at a height of 1.5 m above the ground. The number of mesophilic bacteria was detected after 24-48 hrs incubation at 37°C on tryptone soya agar (TSA; Merck, Darmstadt, Germany). The number of psychrophilic bacteria was detected after 72 hrs incubation at 22°C on TSA. The number of fungi was detected by a 5-day long incubation at 28°C on chloramphenicol yeast glucose agar. Results: In the Lubelskie voivodeship, the mean concentration of psychrophilic bacteria was significantly higher than in the Pomeranian voivodeship (2739 vs 608 CFU/m3, respectively), the mean concentration of mesophilic bacteria was significantly higher (2493 vs 778/m3, respectively) and the concentration of fungi was significantly higher (3840 vs 688 CFU/m3, respectively). We also showed a statistically significant relationship between the number of children with recently diagnosed T1DM and the mean concentration of psychrophilic and mesophilic bacteria in the Pomeranian and Lubelskie voivodeships (P<0.001). Moreover, we found a significant relationship between the number of new cases of T1DM in children and the mean concentration of fungi in bioaerosols in the Lubelskie voivodeship (P<0.001), but not in the Pomeranian voivodeship (P=NS). Conclusion: The results of our research showed that there is a higher concentration of microbial particles in the Lublin voivodeship. Therefore, we recommend changes in climate for children (trips to the sea, mountains, etc) as often as possible.

5.
Int Marit Health ; 70(4): 239-243, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31891178

RESUMO

BACKGROUND: Knowing the numbers of bacteria in coastal atmospheric air as well as in coastal waters significantly contributes to a better understanding of the processes affecting the health of people who stay temporarily or permanently in areas where the synergistic effect of the atmospheric conditions and the aquatic environment on a human body is particularly strong. MATERIALS AND METHODS: Seawater and air samples were collected from 22 May to 22 July 2018 in the seaside towns of Hel, Puck, Gdynia, Sopot, Gdansk-Brzezno, all located along the Gulf of Gdansk. The number of psychrophilic, mesophilic as well as coliform bacteria and Escherichia coli was determined in both the water and the ambient air samples. In total, 232 seawater and coastal air samples were collected for the study purposes. RESULTS: The study showed a deterioration of coastal waters and atmospheric air in the Gulf of Gdansk which may have resulted from an increase of potentially pathogenic mesophilic bacteria following the emergency discharge of raw sewage from the Gdansk-Wschod wastewater plant. CONCLUSIONS: An increase in the number of coliform bacteria and Escherichia coli in the seawater and in the air across the Gulf of Gdansk is related to the emergency sewage discharge.


Assuntos
Microbiologia do Ar , Bactérias/isolamento & purificação , Fezes/microbiologia , Água do Mar/microbiologia , Esgotos/microbiologia , Microbiologia da Água , Poluição da Água/análise , Carga Bacteriana , Emergências , Monitoramento Ambiental , Polônia
6.
Nephron ; 138(1): 29-34, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28988230

RESUMO

BACKGROUND AND AIMS: Urinary neutrophil gelatinase associated lipocalin (uNGAL) and urinary kidney injury molecule-1 (uKIM-1) are markers of acute kidney injury. The albuminuria is a well-known abnormality after physical exercise. The aim of this study was to investigate changes in uNGAL and uKIM-1 after intensive exercise causing albuminuria. METHODS: The study population consisted of 19 participants (10 males and 9 females). The mean age of participants was 35.74 years. All were fit amateur runners; the mean body mass index was 21.99 in females and 24.71 in males. The subjects underwent a graded treadmill exercise test (GXT) according to the Bruce protocol. Maximal oxygen consumption (VO2max) was measured. Immediately before and after the test urine was collected. Urinary creatinine, albumin, NGAL, and KIM-1 were measured. Albumin to creatinine (ACR), KIM-1 to creatinine (KCR), and NGAL to creatinine (NCR) ratios were calculated. RESULTS: The mean VO2max was 53.68 in females and 59.54 mL/min/kg in males. Albuminuria and ACR were significantly higher after exercise. An increase in the ACR from 8.82 to 114.35 mg/g (p < 0.01) was observed. uKIM-1 increased significantly after exercise from 849.02 to 1,243.26 pg/mL (p < 0.05). KCR increased from 1,239.1 to 1,725.9 ng/g but without statistical significance (p = 0.07). There were no statistical changes in pre- and post-run uNGAL levels. There was no correlation between post-GXT albuminuria and uKIM-1. CONCLUSIONS: uKIM-1 is a very sensitive marker of kidney dysfunction. In our study, uKIM-1 increased significantly after a very short period of exercise. It is not clear if the increase in KIM-1 is caused by post-exercise albuminuria.


Assuntos
Exercício Físico , Receptor Celular 1 do Vírus da Hepatite A/genética , Lipocalina-2/genética , Lipocalinas/urina , Adulto , Albuminúria/genética , Albuminúria/metabolismo , Limiar Anaeróbio , Creatinina/sangue , Teste de Esforço , Feminino , Humanos , Lipocalina-2/urina , Masculino , Pessoa de Meia-Idade , Adulto Jovem
7.
Artigo em Inglês | MEDLINE | ID: mdl-29073289

RESUMO

INTRODUCTION: The aim of our study was to evaluate the relation between the concentration of particulate matter of less than 10 µm in diameter (PM10) in air and the effect of psychrophilic bacteria, mesophilic bacteria and mould fungi on the number of new cases of type 1 diabetes mellitus in children and adolescents in the Lubelskie Voivodeship in the years 2015-2016. PATIENTS AND METHODS: Epidemiological data on the number of new cases of T1DM was obtained from the Department of Paediatric Endocrinology and Diabetology of the Medical University in Lublin. The number of births for the year 2015 and 2016 in the Lublin Voivodeship was acquired from the statistical yearbook by the Polish Central Statistical Office (GUS). Data on PM10 concentration in the Lubelskie Voivodeship was obtained from the report and annual evaluations of air quality prepared by the Voivodeship Inspectorate of Environmental Protection (WIOS) in Lublin. The analysis of psychrophilic bacteria, mesophilic bacteria and mould fungi in air was performed with use of the impact method and an air sampler. RESULTS: In the years 2015-2016 in the Lubelskie Voivodeship the number of births was 39 381 and 152 new cases of type 1 diabetes mellitus were recorded. The annual and 24-hour concentration of PM10 in air in 2015 was higher compared to 2016; however, the difference was not statistically significant. Moreover, we detected a higher number of psychrophilic bacteria 2739 vs 1000 CFU/m3 and a significantly higher number of mesophilic bacteria 92493 vs 1000 CFU/m3 than the norm specified in the Polish standard PN-89/Z-04111/02. A further analysis of air samples collected in the Lubelskie Voivodeship revealed lower a concentration of mould fungi compared to the Polish standard PN-89/Z-04111/02 (3840 vs 5000 CFU/m3, respectively). We isolated 9 types of mould fungi and 1 type of yeast-like fungus that are thought to have a negative effect on people's health. The statistical analysis revealed a relation between the number of new cases of T1DM and the number of psychrophilic bacteria (ß= 2.86; p<0.05), mesophilic bacteria (ß = 2.824; p<0.05) and the number of mould fungi (ß=2.923; p<0.001). The analysis of linear regression revealed a relation between the number of new T1DM cases and mean annual concentration of PM10 for the year 2016 (p<0.001). However, there was no relation observed between the number of new cases of T1DM and the mean annual concentration of PM10 in air in the Lubelskie Voivodeship in 2015. CONCLUSIONS: Our preliminary results confirm the not yet fully explored relation between air pollution and the risk of type 1 DM in children and adolescents.


Assuntos
Microbiologia do Ar , Poluição do Ar/efeitos adversos , Poluição do Ar/estatística & dados numéricos , Diabetes Mellitus Tipo 1/etiologia , Exposição Ambiental/efeitos adversos , Material Particulado/análise , Material Particulado/toxicidade , Adolescente , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/epidemiologia , Monitoramento Ambiental/métodos , Feminino , Humanos , Masculino , Polônia/epidemiologia
8.
Environ Monit Assess ; 184(4): 2017-29, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21656000

RESUMO

The paper presents water-quality evaluation based on an 8-year monitoring programme in the Gdansk Municipality region, on the Southern coast of the Baltic Sea. The studies were carried out from 2000 to 2007 by surface water analysis at 15 various sites within eight watercourses. Sampling sites included rather urbanized or developed lands, farming fields and non-polluted city recreational areas such as parks and forests. Most of the watercourses were sampled monthly at two locations, one within the upper course of the watercourse and the other near its mouth. In all samples, eight parameters of water quality were determined: total suspended solids, dissolved oxygen, water temperature, oxygen saturation, 5-day biochemical oxygen demand, chemical oxygen demand, total phosphorus and total nitrogen concentration. Interpretation of the obtained results revealed that examination of those basic physicochemical parameters permits to discriminate initially watercourses with respect to level of water contamination. During the research, a large dataset was obtained and it was described by both basic statistical parameters and chemometric method of cluster analysis. The paper presents relations between analysed parameters and influence of land exploitation mode on water quality and describes variation of the results both in space and time.


Assuntos
Monitoramento Ambiental/métodos , Rios/química , Poluentes Químicos da Água/análise , Qualidade da Água , Cidades , Polônia
9.
Int Marit Health ; 61(1): 41-3, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20496328

RESUMO

Bioaerosol formation is an important process of mass and energy exchange between the sea and the atmosphere by means of droplets of marine dust. Studies of marine aerosol activity developed in the last decades of the 20th century. Those studies revealed that concentrations of bacteria in aerosol droplets were hundreds of times higher than were those measured in superficial marine waters. Moreover, it was determined that aerosol activity at sea can influence the sanitary condition of the air, especially in seaside areas. Examinations of air composition in coastal regions were performed on the beaches of the Tri-city, Sobieszewo, and Komary. Airborne microorganisms were also investigated in the marine zone at the Vistula river mouth. The air samples were collected by a filtration method using Sartorius apparatus. The exposed filters were then placed onto agar media in Petri dishes and incubated. All measurements are expressed in CFU/m3, i.e. colony forming units per cubic metre of examined air. Meteorological parameters such as temperature, humidity, and wind speed and direction were also measured. The obtained results revealed statistically significant trends between the total number of bacteria and fungal spores, and the sampling season. The greatest number of microorganisms was noted in spring and autumn. Correlation analysis showed that a statistically significant relationship exists between the microbial abundance and the wind direction, wind speed, and the sampling site location. The maximum number of fungal spores was detected in the areas of Gdynia and Gdansk Brzezno when south-west winds were blowing from the land. The highest number of bacteria was observed at the sampling stations located closest to the Vistula river mouth (Sobieszewo and Komary).


Assuntos
Aerossóis , Praias , Poluentes Atmosféricos/análise , Fungos/isolamento & purificação , Humanos , Polônia , Esporos Bacterianos/isolamento & purificação
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