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Bioassay and alpha spectrometry in indirect monitoring of Spanish workers exposed to enriched uranium

Abstract

Workers at risk of exposure to uranium compounds should be monitored and their internal exposure quantified in terms of committed effective dose E(50) in mSv. In vitro bioassay methods can quantify uranium in urine and faeces at low activity levels. Alpha spectrometry (AS) is the most common method used for monitoring alpha-emitting radionuclides in internal dosimetry services. It provides isotopic information and low minimum detectable activity (MDA) values (≤0.50 mBq per sample). This study reports the results of a five-year monitoring of workers exposed to uranium at a Spanish Juzbado facility, which produces nuclear fuel elements enriched with up to 5 % of 235U. Monitoring included about 100 workers per year, most of whom had worked at the facility for more than 10 years before the individual monitoring programme was established. We analysed nearly 550 samples of more than 200 workers over five years. The obtained results indicate that workers were adequately protected from uranium exposure through inhalation and had an acceptably low chronic intake at the facility.

Open access
Chemical composition and antioxidant, cytotoxic, and insecticidal potential of Valeriana alliariifolia in Turkey

Abstract

Valeriana is a common plant species used for various healing purposes in folk medicine since antiquity. This study investigates the phytochemical profile, antioxidant, cytotoxic, and insecticidal activity of Valeriana alliariifolia Adams, a species that has traditionally been used in Turkey. For the analyses we prepared four root extracts of V. alliariifolia Adams using hexane (HM1), chloroform (CM1), ethanol (EM1), and water (WM1) for maceration. Additionally, two extracts were also prepared from its roots by maceration separately with ethanol (EM2) and water (WM2). One sample was prepared as a water infusion (WI), according to the procedure used in Turkish traditional medicine. The 2,2-Diphenyl-1-picrylhydrazyl (DPPH) scavenging and 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS) radical cation scavenging activity tests showed that ethanol extracts had the strongest antioxidant activity: EM1 (IC50 – DPPH: 17.694 µg/mL; ABTS: 23.8 µg/mL) and EM2 (IC50 – DPPH: 20 µg/mL; ABTS: 21.5 µg/mL). The hexane extract, HM1, was the most cytotoxic (IC50<10 µg/mL against HepG2 and HUVEC) and EM2 strongly cytotoxic (IC50<10 µg/mL against HepG2 and IC50: 11.96 µg/mL against HUVEC). The extracts with demonstrated cytotoxic activities were further examined to check their insecticidal activity against adult female mosquito Aedes aegypti and first instar Ae. aegypti larvae. HM1 was the most effective (90±10 %), which was consistent with its cytotoxic activity. Because of the high antioxidant, cytotoxic, and insecticidal activities, we ran phytochemical analyses of the HM1, EM1, and EM2 extracts with GC-MS (for HM1) and LC-MS/MS (for EM1 and EM2). We also analysed the composition of the essential oil obtained from V. alliariifolia roots by micro-distillation in order to compare its content with HM1, which contains volatile compounds. Phytochemical analyses revealed that the major compound in HM1 was isovaleric acid (16 %) and in the essential oil 1,8-cineole (2.9 %). EM1 and EM2 contained 5-O-caffeoylquinic acid (chlorogenic acid), verbascoside (acteoside), and 3,5-dicaffeoylquinic acid as major components. In the light of our findings and available literature, we can conclude that V. alliariifolia has a good bioactive potential that could be used for different purposes, including the development of new agents for the treatment of various diseases. The difference in the content between the essential oil and HM1 was remarkable. It suggests that the variability observed in the activity of the samples was a result of composition and that, therefore, the aim of treatment should dictate which type of preparation is to be selected. An added value of our study is that it determined verbascoside and methylquercetin rutinoside for the first time in the Valeriana extracts.

Open access
A cross sectional study of salt content in bakery bread in Zagreb, Croatia

Abstract

Reducing salt content in bread is the essential part of a national strategy for salt reduction with the goal of long-term national general health improvement. In this study we have analysed salt content in three types of bread available in 25 small and five national industrial bakeries in Zagreb, Croatia. Samples of white wheat bread, dark wheat bread, and other types of bread were collected, and the salt content was determined with the Mohr method. Salt content varied widely between bakeries, with an average content of 2.30±0.22 g per 100 g of bread, which is almost twice the threshold content (1.4 %) defined by the Croatian National Regulation on Cereals and Cereal Products. Further efforts are necessary to teach bakers how to reduce salt content without affecting quality or flavour. These should go hand in hand with continuous monitoring of how the legal provisions are implemented.

Open access
A feasibility study on the association between residential greenness and neurocognitive function in middle-aged Bulgarians

Abstract

Recent research has indicated that exposure to residential vegetation (“greenness”) may be protective against cognitive decline and may support the integrity of the corresponding brain structures. However, not much is known about these effects, especially in less affluent countries and in middle-aged populations. In this study, we investigated the associations between greenness and neurocognitive function. We used a convenience sample of 112 middle-aged Bulgarians and two cognitive tests: the Consortium to Establish a Registry for Alzheimer’s Disease Neuropsychological Battery (CERAD-NB) and the Montreal Cognitive Assessment (MoCA). In addition, structural brain imaging data were available for 25 participants. Participants’ home address was used to link cognition scores to the normalised difference vegetation index (NDVI), a measure of overall neighbourhood vegetation level (radii from 100 to 1,000 m). Results indicated that higher NDVI was consistently associated with higher CERAD-NB and MoCA scores across radial buffers and adjustment scenarios. Lower waist circumference mediated the effect of NDVI on CERAD-NB. NDVI100-m was positively associated with average cortical thickness across both hemispheres, but these correlations turned marginally significant (P<0.1) after correction for false discovery rate due to multiple comparisons. In conclusion, living in a greener neighbourhood might be associated with better cognitive function in middle-aged Bulgarians, with lower central adiposity partially accounting for this effect. Tentative evidence suggests that greenness might also contribute to structural integrity in the brain regions regulating cognitive functions. Future research should build upon our findings and investigate larger and more representative population groups.

Open access
In search of optimal psychoactivation: stimulants as cognitive performance enhancers

Abstract

An increasing number of people, students in particular, seek substances that improve their cognitive functioning. The most popular group of pharmacological cognitive enhancers (PCEs) are stimulants. Available studies suggest a small beneficial effect of methylphenidate and amphetamine on memory, executive functions, and processing speed. However small, this effect can make the difference between success and failure. In recent years, research has focused on the additional beneficial effect on the emotional state, increased motivation, and placebo-induced cognitive enhancement. This paper briefly reviews the latest and most important research on the relationship between popular stimulants and cognitive enhancement. One cannot understand this relationship without understanding the Yerkes-Dodson law, which explains the relationship between the degree of arousal and performance. It suggests that the effect of stimulants is a dose-dependent continuum. This law has repeatedly been confirmed by studies in which an optimal level of psychoactivation for cognitive enhancement was obtained with low stimulant doses, whereas exceeding the effective dose resulted in cognitive deficits, psychomotor agitation, and addiction. A separate section has been devoted to modafinil, an increasingly popular stimulant that differs from the rest in neurochemical profile and behavioural effects.

Open access
An overview of microtubule targeting agents for cancer therapy

Abstract

The entire world is looking for effective cancer therapies whose benefits would outweigh their toxicity. One way to reduce resistance to chemotherapy and its adverse effects is the so called targeted therapy, which targets specific molecules (“molecular targets”) that play a critical role in cancer growth, progression, and metastasis. One such specific target are microtubules. In this review we address the current knowledge about microtubule-targeting agents or drugs (MTAs/MTDs) used in cancer therapy from their synthesis to toxicities. Synthetic and natural MTAs exhibit antitumor activity, and preclinical and clinical studies have shown that their anticancer effectiveness is higher than that of traditional drug therapies. Furthermore, MTAs involve a lower risk of adverse effects such as neurotoxicity and haemotoxicity. Several new generation MTAs are currently being evaluated for clinical use. This review brings updated information on the benefits of MTAs, therapeutic approaches, advantages, and challenges in their research.

Open access
Sleep coaching: non-pharmacological treatment of non-restorative sleep in Austrian railway shift workers

Abstract

Sleep coaching by Holzinger & Klösch™ is a new, Gestalt therapy-based holistic approach to non-pharmacological treatment of non-restorative sleep. It includes psychotherapeutic aspects which enable participants to improve their sleep quality by developing their own coping strategies as a daily routine. Dream work and relaxation techniques are also part of the programme. The aim of this study was to measure the effectiveness of a two-day sleep coaching seminar on sleep quality, daytime sleepiness, and work and life quality in shift workers employed in an Austrian railway company (Österreichische Bundesbahnen, ÖBB). Thirty shift workers (28 male; mean age=24±45.90, age range 24–56 years) answered the same survey before and six months after the seminar (baseline and follow-up) containing items of the Pittsburgh Sleep Quality Index (PSQI) and the Epworth Sleepiness Scale (ESS), their chronotype, personality factors, and burnout risk factors. The baseline findings in this group were compared with those of non-completers (who did not take the follow-up survey) (N=154) to see if the two groups differed significantly enough to create a bias among completers (who took the follow-up survey as well). Groups differed significantly in burnout levels as well as sleep duration, but not in the distribution of critical PSQI and ESS values. The two-day sleep coaching seminar resulted in a significant improvement in total PSQI score and subjective sleep quality and in a significant reduction in diurnal fatigue, sleep latency, and daytime sleepiness. Nevertheless, more research with a larger sample and a longitudinal design is needed to establish the long-term effects of sleep coaching.

Open access
Achondrogenesis type 2 in a newborn with a novel mutation on the COL2A1 gene

Abstract

Achondrogenesis is a group of rare and fatal disorders occurring in approximately one in every 40,000-60,000 newborns. Achondrogenesis is classified in three groups, as Achondrogenesis type 1A (Houston-Harris type or AC-G1A), Achondrogenesis type 1B (Parenti-Fraccaro type or ACG1B) and Achondrogenesis type 2 (Langer-Saldino type or ACG2), depending on clinical and radiological findings. Achondrogenesis Type 2 is a lethal skeletal dysplasia that is typically characterized by short arms and legs, a small chest with short ribs, lung hypoplasia, a prominent forehead, a small chin, and an enlarged abdomen that may accompanied by polydramnios and hydrops. This study contributes to the literature by presenting a patient who was admitted to the Level ΙΙΙ Neonatal Intensive Care Unit (NICU), Bursa, Turkey), with extremely short extremities, a small chest, abdominal distention and respiratory distress, who was diagnosed with ACG2. On the COL2A1 gene, genetic analysis with next generation sequencing (NGS), was revealed to have a heterozygous missense variation, c.2546G>A, p.Gly849Asp mutation, which is a different genetic variant that has not been previously described in the literature.

Open access
Associations between vaspin rs2236242 gene polymorphism, walking time and the risk of metabolic syndrome

Abstract

The associations between serum vaspin levels and metabolic or coronary artery disease (CAD) and polycystic ovary syndrome (PCOS) is under the scope of current researchers. Therefore, this adipokine can be considered as a biomarker of metabolic syndrome (MetS). The aim of the study was to analyze the associations between the vaspin rs2236242 polymorphism and physical activity in relation to MetS and its components. The analysis involved the genetic material and clinical data of 108 individuals with MetS and 110 controls. Vaspin rs2236242 polymorphism was detected using the tetra-primer amplification-refractory mutation system polymerase chain reaction (T-ARMS PCR) method. The TA genotype of vaspin rs2236242 was associated with a greater risk of MetS and its components compared with the TT genotype. The analysis of interactions between genotype and walking time revealed that a walking time longer than 60 min./day significantly decreased the risk of MetS in the TA carriers (p = 0.007). The obtained results suggest that any unfavorable effect of the TA genotype of the vaspin rs2236242 polymorphism can be essentially reduced, or even reversed, in a case of individuals walking longer than 60 min. a day. The analysis of the interaction between vaspin rs2236242 polymorphism and walking showed that a walking time of longer than 1 hour a day significantly reduced the risk of MetS, elevated blood pressure and triglycerides concentration.

Open access
Comparative expression analysis of human endogenous retrovirus elements in peripheral blood of children with specific language impairment

Abstract

Specific language impairment (SLI) is a psychiatric condition with a complex etiology and a substantial genetic basis that affects children's verbal communication abilities. In this study, we examined the expression of five different human endogenous retrovirus elements (HERVs) in a cohort of 25 children with SLI and 25 healthy children in the control group. Human endogenous retrovirus elements, a diverse group of repetitive DNA sequences, can potentially cause considerable genetic heterogeneity. They had been integrated in the genome of our ancestors throughout evolution and now consist of about 8.0% of the human genome. Several HERV loci are transcribed in various cell types. Their expression in peripheral blood and in the brain is altered in many neurological and psychiatric diseases. To date, HERV expression profiles have never been studied in patients with SLI. This study aimed to elucidate differentially regulated human endogenous retroelements in peripheral blood of children with SLI, in comparison with healthy controls, through quantitative reverse tran-scription-polymerase chain reaction (qRT-PCR) methodology. Our results show that two genes: HERV-K (HLM-2) gag and HERV-P env were expressed at lower levels in the blood samples from SLI children in comparison with those in the control group.

Open access