One-hour Exposure Research Articles

Experimental investigation into the effect of transparent fireproof coatings on charring behavior of glued laminated timber exposed to fire

As timber structures evolve towards greater heights and longer spans for buildings, there is a pressing need to enhance the fire resistance of timber structures. Considering the charring behavior of timber is crucial to the fire resistance of timber structures, it is a promising way to retard the charring behavior of timber and further enhance the fire resistance by applying transparent fireproof coatings. In this study, a series of fire tests were conducted to investigate the effect of transparent fireproof coatings on the charring behavior of Douglas fir glued laminated timber (Glulam) under small-scale ISO 834 standard fire conditions. Different coating types, coating quantities, exposed time to fire and member sizes were considered in the experiments. The experimental results including temperature profiles, maximum temperature, and charring rates for uncoated and coated Glulam specimens were carefully recorded and analyzed. Then, the effect of transparent fireproof coatings was quantified by the proposed ratio of delayed charring. The main mechanism of the delayed charring in fire was finally discussed. This study demonstrated that two transparent fireproof coatings can both effectively lower the temperature at different depths and delay the charring behavior of timber. The reduction in charring rates increased with the increase of coating quantity and decreased as the fire exposure time progressed. The ratio of delayed charring for two coatings can be over 30 % in the initial stage of fire and over 20 % for 1-h standard fire exposure. This study can provide technical support for enhancing the fire resistance of timber structures using transparent coatings.

Male humpback whales switch to singing in the presence of seismic air guns

Ocean noise produced by seismic exploration has been implicated in causing changes in baleen whale hearing, physiology, feeding, breeding, and migratory behaviours. Here, we observed changes in the mating tactics of humpback whales (Megaptera novaeangliae) during a one-hour exposure to nearby seismic air guns. Males employ a conditional mating strategy where they switch between singing and non-singing tactics. Singing is presumably an advertisement signal, while non-singing behaviours include seeking out and joining with females as well as forming competitive groups. During periods of active air guns, the number of male singing whales increased, and singers were more likely to be observed joining females. Conversely, non-singing males were less likely to engage in joining interactions suggesting that active air guns caused a switch in male breeding tactics. Though we cannot translate these effects into changes in breeding success, this indicates that seismic exploration has the potential to alter breeding behaviours in baleen whales.

Peracetic Acid Emissions and Exposures during Building Disinfection Events

Since the onset of the COVID-19 pandemic, there has been a significant increase in chemical disinfection of high-touch surfaces in buildings. Peracetic acid (PAA) is a commercially available and widely used disinfectant for inactivation of viruses and bacteria. The objective of this study is to evaluate indoor PAA emissions and exposures during full-scale building disinfection events via real-time PAA measurement in a test house. The measurements revealed that PAA-based surface disinfection can lead to a significant increase in PAA concentrations in indoor air (0.1–1 mg/m3). PAA emission factors (EFs) for spray-based products ranged from 0.22–0.59 mg of PAA emitted per mg of PAA sprayed, indicating that a significant fraction of the PAA applied to surfaces is emitted into the indoor atmosphere. Inhalation intake fractions (iFs) ranged from 1,597–3,436 ppm for a one-hour exposure period, demonstrating that around 0.16–0.34% of the PAA emitted into indoor air can be inhaled by an occupant during a disinfection event. iFs were similar between the active disinfection period and the subsequent concentration decay period, suggesting that inhalation intake is important both during and after the disinfectant is applied. Real-time breathing zone (BZ) experiments demonstrated that occupants can be exposed to elevated PAA concentrations beyond those measured in the bulk indoor air due to the source-to-BZ proximity effect inherent in disinfection processes. The PAA EFs enabled modeling of PAA dynamics in different indoor environments. Model results show that PAA concentrations often exceed exposure limits, indicating a need for improved exposure mitigation strategies.

Extracellular phospholipase production by Malassezia pachydermatis strains and its inhibition by selected antimycotics and plant essential oil components

Extracellular phospholipase (EPL) plays an important role in the pathogenesis of the yeast Malassezia pachydermatis. Currently, the attention of researchers is focused on studying the virulence factors involved in this process and searching solutions to reduce their activity. One of the options is the use of natural remedies as anti-virulence agents. This study is aimed at investigating the production of extracellular phospholipase in M. pachydermatis strains (18 samples) and followed by the time-dependent inhibitory effect of selected azole antifungals (itraconazole, posaconazole and voriconazole) and plant essential oil components (terpinen-4-ol, thymol, carvacrol, eugenol and geraniol), evaluated by Egg Yolk Agar plate method. Almost all strains (17 isolates, (94.4%) were found to be intense EPL producers. A significant, time-dependent inhibition of EPL was noted after 1-, 3- and 6-h exposure of Malassezia cells to itraconazole (26.4%, 47.2% and 50.9%, respectively) compared to exposure to posaconazole (26.4%, 28.3% and 28.3%, respectively) and voriconazole (18.8%, 20.8% and 35.8%, respectively). After one-hour exposure to plant essential oil components, the best inhibitory effect was recorded for eugenol (62.3%), followed by terpinen-4-ol and thymol (56.6%), geraniol (41.5%) and carvacrol (26.4%). A 3-h exposure revealed that thymol retained the best inhibitory effect (88.7%) on EPL production, followed by carvacrol (73.6%), eugenol (56.6%), terpinen-4-ol (52.8%) and geraniol (49.1%). After 6-h exposure, no growth of M. pachydermatis strains exposed to carvacrol was observed, and the inhibitory efficiency for the other tested essential oil (EO) components achieved 88.7%. The obtained results indicate the promising efficacy of plant essential oils components in the inhibition of virulence factors such as EPL production.

INSIGHT INTO ANTI-CORROSION EFFECT OF MAMMILLARIA PROLIFERA FRUIT EXTRACT AS A GREEN INHBITOR FOR MILD STEEL IN HCl SOLUTION

In this study, it was aimed to examine the adsorption and corrosion behaviours of the aqueous extract of Mammillaria prolifera, a cactus fruit, in 1.0 M HCl solution using experimental methods such as potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). Mammillaria prolifera is a cactus species from the Cactaceae family, commonly known as Texas nipple cactus. Experiments were realized for aqueous extracts of four different Mammillaria prolifera fruits. The results indicate that the aqueous extract solution of cactus fruit has outstanding anti-corrosive performance of over 90% at the optimum concentration of 0.120% (w/v). In addition to electrochemical experiments, FE-SEM surface images were taken as another indicator of high inhibition. The results showed that the mild steel surface immersed in the inhibited electrolyte solution at 298 K after one-hour exposure did not contain cracks, pits or deformations compared to the inhibitor-free surface. As a result, experimental measurements and FE-SEMsurface images support each other.

Comparative Analysis of Anticonvulsant Activity of Trans and Cis 5,5'-Diphenylhydantoin Schiff Bases.

Recently, the four 5,5'-diphenylhydantoin Schiff bases, possessing different aromatic species (SB1-Ph, SB2-Ph, SB3-Ph and SB4-Ph) were synthesized, characterized, and evaluated for anticonvulsant activity in combination with phenytoin. In the present study, the SB1-Ph and SB4-Ph compounds were selected, based on their anticonvulsant potency, and compared with their cis isomers, prepared after a one-hour exposure to the UV source, for their anticonvulsant potency in the maximal electroshock (MES) test and the kainate (KA)-induced status epilepticus (SE) test in mice. In the MES test, the cisSB1-Ph compound exhibited superior to phenytoin and trans isomer activity in the three tested doses, while the cisSB4-Ph compound entirely suppressed the electroshock-induced seizure spread at the highest dose of 40 mg/kg. Pretreatment with the cisSB1-Ph compound and the cisSB4-Ph at the doses of 40 mg/kg, respectively, for seven days, significantly attenuated the severity of KA SE compared to the matched control group pretreated with a vehicle, while phenytoin was ineffective in this test. The cisSB4-Ph but not the cisSB1-Ph demonstrated an antioxidant effect against the KA-induced SE in the hippocampus. Our results suggest that trans-cis conversion of 5,5'-diphenylhydantoin Schiff bases has potential against seizure spread in the MES test and mitigated the KA-induced SE. The antioxidant potency of cisSB4-Ph might be associated with its efficacy in mitigating the SE.

Feasibility of a Circadian Lighting Intervention to Promote Sleep in College Students

College students report poor sleep quality that impacts class attendance, productivity, and overall success in college. Circadian lighting has helped to regulate sleep patterns and improve sleep quality in populations who traditionally experience poor sleep. A feasibility study was conducted to determine the practicality of conducting a study in which a circadian lighting intervention would be implemented in college students’ dorms to study the effect on sleep, mood, and productivity. This study examined the process, resources, data management, and preliminary efficacy of a 4-wk, daily, one-hour lightbox exposure. Results indicated the lightbox was well-received by students. Recommendations to facilitate the study include improved recruitment efforts, data management, use of a research-grade activity tracker, modification of data collection days, and utilization of research associates to assist in data collection. Preliminary outcomes showed improved sleep quality and productivity for schoolwork in this sample of college students.

Paper 08: In Vitro Effects of Triamcinolone and Methylprednisolone on the Viability and Mechanics of Native Articular Cartilage

Objectives: The chondrotoxic effects of methylprednisolone acetate (MP) and triamcinolone acetonide (TA) have been well described. Prior studies have demonstrated a dose-dependent chondrotoxic effect of intra articular (IA) steroids starting at 7 mg for MP and 18 mg for TA. However, the effects of these steroids on the mechanical properties of articular cartilage are largely unknown. The purpose of this study was to investigate the in vitro effects of a single one-hour MP or TA exposure on the viability, mechanics, and biochemical content of native articular cartilage explants. Methods: Articular cartilage explants (n=6 per group) were harvested from the femoral condyle of the bovine stifle. Explants were exposed to chondrogenic medium containing a clinical dose of MP or TA for one hour, followed by fresh medium wash and exchange. Explants in the negative control group underwent the same treatment with chondrogenic medium alone. At t=24 hours post-treatment, samples were assessed for viability (live/dead), mechanical properties (creep indentation and Instron tensile testing), biochemical (collagen and glycosaminoglycan) content, and pyridinoline cross linking via mass spectrometry. Results: Mean cell viability was significantly decreased in native explants exposed to MP (35.5%) compared to control (49.8%, p < 0.001) and TA (45.7%, p = 0.003) (Figure 1). There was significant weakening of mechanical properties of steroid-treated native explants when compared to control (Figure 2), with decreases in aggregate modulus (646.3 kPa vs 312.8 kPa [MP] and 257.0 kPa [TA), p < 0.001), shear modulus (370.1 kPa vs 191.2 kPa [MP] and 157.4 kPa [TA], p < 0.001), and ultimate tensile strength (UTS) (9.650 MPa vs 5.648 MPa [MP], p = 0.021 and 6.065 MPa [TA], p = 0.040). The Young’s modulus in TA-exposed native cartilage (7.924 MPa) was significantly lower than MP (12.35 MPa, p = 0.026) exposed explants but not significantly different compared to control (11.97 MPa, p =0.072). No significant differences in collagen and glycosaminoglycan content were found in the steroid-treated groups (Figure 3). Pyridinoline cross linking was significantly decreased in explants exposed to TA compared to control (p = 0.027). Conclusions: The results of this in vitro study suggest that a single clinical dose of MP is chondrotoxic and that a single clinical dose of MP or TA can lead to substantial early decreases in both the tensile and compressive properties of native articular cartilage. The shear modulus of steroid-exposed explants in this study dropped 48-57% compared to healthy control. In human knee cartilage, drops in shear modulus of this magnitude have been correlated with the progression from healthy knee cartilage to ICRS grade 1-2 osteoarthritis. Furthermore, decreases in Young’s modulus by 25-50% have been correlated with the same degree of osteoarthritis, and the Young’s modulus of steroid exposed cartilage dropped an average of 34% in this study. Although there were no detectable changes to the extracellular matrix composition or structure, a single one-hour steroid exposure was enough to cause chondrotoxicity and altered mechanics to native explants 24 hours after exposure, which raises the concern for risk of mechanical failure of the cartilage tissue. Clinicians should be judicious regarding use of intra-articular steroids, particularly in patients with intact healthy articular cartilage.

The Fifth Bioelectronic Medicine Summit Hosted by the Feinstein Institutes for Medical Research (Manhasset, NY) and Columbia Engineering (NY, NY) at The Garden City Hotel, Garden City, NY 11530 on October 11-12th, 2022- Bioelectronic Medicine: Today’s Tools, Tomorrow’s Therapies

The Fifth Bioelectronic Medicine Summit Hosted by the Feinstein Institutes for Medical Research (Manhasset, NY) and Columbia Engineering (NY, NY) at The Garden City Hotel, Garden City, NY 11530 on October 11-12th, 2022- Bioelectronic Medicine: Today’s Tools, Tomorrow’s Therapies

The mitigation effect of free ammonia and free nitrous acid on nitrous oxide production from the full-nitrification and partial-nitritation systems

The potentials of using endogenous free ammonia (FA) and free nitrous acid (FNA) as nitrous oxide (N2O) mitigators were investigated in treatment of both mainstream and sidestream wastewater. Although the N2O emission factor of a sidestream partial-nitritation (PN) reactor (averaged 1.70 % ± 0.39 %, n = 30) was about 2.4 times higher than a mainstream full-nitrification (FN) reactor (averaged 0.72 % ± 0.24 %, n = 30) (P < 0.01), one-hour exposure of PN sludge to 1.5 mg HNO2-N/L FNA could virtually abolish N2O emission. As for FN sludge, both 45 mg NH3-N/L FA and 0.015 mg HNO2-N/L FNA successfully mitigated N2O production at varying dissolved oxygen (DO) levels (50 % vs 61 %), while 1.5 mg HNO2-N/L FNA not only reduced more N2O (92 %) but also altered the N2O dependency on DO. Both FNA and FA sludge treatment were effective N2O mitigation strategies with FNA toward the end of carbon neutrality and FA being more economically appealing (2 % cost saving).

The Role of Mitochondrial Enzymes, Succinate-Coupled Signaling Pathways and Mitochondrial Ultrastructure in the Formation of Urgent Adaptation to Acute Hypoxia in the Myocardium.

The effect of a single one-hour exposure to three modes of hypobaric hypoxia (HBH) differed in the content of O2 in inhaled air (FiO2-14%, 10%, 8%) in the development of mitochondrial-dependent adaptive processes in the myocardium was studied in vivo. The following parameters have been examined: (a) an urgent reaction of catalytic subunits of mitochondrial enzymes (NDUFV2, SDHA, Cyt b, COX2, ATP5A) in the myocardium as an indicator of the state of the respiratory chain electron transport function; (b) an urgent activation of signaling pathways dependent on GPR91, HIF-1α and VEGF, allowing us to assess their role in the formation of urgent mechanisms of adaptation to hypoxia in the myocardium; (c) changes in the ultrastructure of three subpopulations of myocardial mitochondria under these conditions. The studies were conducted on two rat phenotypes: rats with low resistance (LR) and high resistance (HR) to hypoxia. The adaptive and compensatory role of the mitochondrial complex II (MC II) in maintaining the electron transport and energy function of the myocardium in a wide range of reduced O2 concentrations in the initial period of hypoxic exposure has been established. The features of urgent reciprocal regulatory interaction of NAD- and FAD-dependent oxidation pathways in myocardial mitochondria under these conditions have been revealed. The data indicating the participation of GPR91, HIF-1a and VEGF in this process have been obtained. The ultrastructure of the mitochondrial subpopulations in the myocardium of LR and HR rats differed in normoxic conditions and reacted differently to hypoxia of varying severity. The parameters studied together are highly informative indicators of the quality of cardiac activity and metabolic biomarkers of urgent adaptation in various hypoxic conditions.

Targeting of SFK and G6PD Contributes to Anti-Leukemic Activity of Novel FLT3 Trisubstituted Purine Inhibitors: Effective Therapeutic Approach for AML with FLT3 Mutations

We have recently developed compound LGR3922, a potent inhibitor of FLT3 receptor tyrosine kinase, which displays selectivity and potency in in vitro and in vivo AML models (compound 7d, Gucky T et al, J Med Chem. 2018;61(9):3855). In addition, LGR3922 showed strong inhibitory activity against Src family kinases (SFK) in the in vitro settings (Fig. 1A; ASH meeting abstract, Radosova Muchova et al, Blood. 2016;128(22):1569). Here, we present additional characterization of the lead compound LGR3922 and demonstrate its potent antileukemic activity in MLL/FLT3-ITD cell lines, murine xenografts and ex vivo primary AML samples. LGR3922 exhibited strong anti-proliferative effect against MV4-11 and MOLM-13 cells. Contrary to quizartinib (quiz), LGR3922 simultaneously reduced phosphorylation levels of FLT3-SFK and their downstream molecules STAT5 and ERK in both AML cell lines. Interestingly, the inhibitory effect of LGR3922 on SFK, STAT5 and ERK increased over time, especially in the MOLM-13 cells. Similar results were only seen for the combination treatment with quiz and dasatinib (das). Dual-targeting of FLT3-SFK by LGR3922 was further confirmed on MV4-11 xenografts. In the long-term in vivo experiment with repeated doses of the tested inhibitors, LGR3922 showed similar trends in initial treatment response as the combination treatment with quiz and das; quiz exhibited less efficient inhibitory effects at this stage. The tumor reduction was most significant (p ≤ 0.0001) in LGR3922 group; 3 out of 6 tumors were completely eradicated during the treatment period (Fig. 1B). Complete tumor eradication (in 1 out of 5 animals) over the treatment period was then seen only in combination quiz and das (Fig. 1B). No adverse effects on blood count parameters or body weight were associated with LGR3922 compared to combination treatment with quiz and das, where temporary body weight loss and only limited weight gain were observed. Next, we searched for additional target of the FLT3/SFK inhibitor that would have a synthetic lethal effect for the kinase pair. Besides the kinases that belong to other druggable nodes of AML-associated networks (Fig. 1A), we also tested antioxidant defense enzymes, previously validated as being synthetic lethal with FLT3 inhibitor therapy (Gregory MA et al. Proc Natl Acad Sci U S A. 2016;113(43):E6669). Indeed, we observed that LGR3922 inhibited G6PD activity, already after one-hour exposure (with a dose response over the concentration range), in contrast to quiz and das. We hypothesize that this activity modulating leukemia cell redox metabolism, cooperating with FLT3/SFK inhibition, may elicit more effective eradication of AML cells than quiz and das or quiz/das combination. We then evaluated toxicity of LGR3922 on normal hematopoiesis using colony forming unit (CFU) assays with progenitor cells from several healthy donor controls. LGR3922 inhibited colony formation in a dose-dependent manner; maximal tolerated concentration (MTC) for all healthy samples was 100 nM, in some samples the reduced granulocyte-macrophage (CFU-GM) and burst forming unit-erythroid (BFU-E) colony forming ability was not observed up to a concentration of 200 nM. Quiz and das exposure showed MTCs at 20 nM and 5 nM, respectively; in quiz/das combination at 10 nM/0.5 nM; 10 nM/5 nM was already toxic. Then, we performed CFU assays on 4 primary human AML samples with FLT3-ITD mutations (n=3) or FLT3-TKD+KMT2A::MLLT3 (n=1). Cultures with LGR3922 at 100 nM reduced the number of colonies by ∼70% in all FLT3-ITD patient samples. The inhibitory effects were comparable to or a little more potent than MTCs of quiz or quiz/das combination. Das culture had significantly lower effect on colony formation for the tested concentrations. In the FLT3-TKD+KMT2A::MLLT3 positive sample, fusion transcript was quantified in harvested colonies. While LGR3922 significantly reduced KMT2A::MLLT3 fusion transcript, no effects were observed for MTCs of single agent cultures with quiz or das. Only a combination of quiz/das exceeding MTC (10 nM/5 nM) resulted in a slight decrease of KMT2A::MLLT3 fusion transcript levels. Taken together, these data suggest effectiveness of our new LGR3922 compound and provide a rationale for further development and testing of this molecule for MLL/FLT3-ITD AMLs, and, potentially, other types of AMLs. Grant support: Program EXCELES, ID Project No. LX22NPO5102; GA19-09086S; MH CZ-DRO (UHKT, 00023736). Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Evaluation of Susceptibility Status of Phlebotomus papatasi, the Main Vector of Zoonotic Cutaneous Leishmaniasis, to Different WHO Recommended Insecticides in an Endemic Focus, Central Iran.

Among neglected zoonotic diseases, leishmaniases caused by Leishmania parasite through infected female sand fly bite, are a group of diseases found in 98 countries and territories representing a critical burden of disease worldwide. Vector management plays a crucial role in reducing the burden of vector-borne diseases by WHO's global plan. The objective of the current study was to assess the susceptibility status of wild phlebotomine sand flies from Esfahan Province, central Iran, to the recommended insecticides by WHO. Sand flies were collected by mouth aspirator in Matin Abad desert Eco-resort and were tested using WHO adult mosquito test kit against Dichlorodiphenyltrichloroethane (DDT) 4%, Deltamethrin 0.05%, Malathion 5% and Propoxur 0.1%. The number of knockdown sand flies were recorded during exposure time in ten minutes interval for DDT and Deltamethrin and they were allowed to recover for 24 hours. Knockdown Time50 (KD50) and KD90 were generated for them using Probit software. They were mounted and identified by valid keys. Among the tested insecticides against female Phlebotomus papatasi, DDT, Deltamethrin, and Malathion recorded the highest mortality rate of 100%, followed by Propoxur with 92.2% mortality for a one-hour exposure. For DDT, KD50 and KD90 were calculated 21.87 and 42.93 and for Deltamethrin, they were 23.74 and 56.50 minutes respectively. Total sand flies exposed with DDT and Deltamethrin shed their leg(s). It is concluded that Ph. papatasi from central Iran is susceptible to DDT, Deltamethrin, Malathion, and Propoxur.

In-vivo dose determination in a human after radon exposure: proof of principle

Radon-222 is pervasive in our environment and the second leading cause of lung cancer induction after smoking while it is simultaneously used to mediate anti-inflammatory effects. During exposure, radon gas distributes inhomogeneously in the body, making a spatially resolved dose quantification necessary to link physical exposure conditions with accompanying risks and beneficial effects. Current dose predictions rely on biokinetic models based on scarce input data from animal experiments and indirect exhalation measurements of a limited number of humans, which shows the need for further experimental verification. We present direct measurements of radon decay in the abdomen and thorax after inhalation as proof of principle in one patient. At both sites, most of the incorporated radon is removed within ~ 3 h, whereas a smaller fraction is retained longer and accounts for most of the deposited energy. The obtained absorbed dose values were 1.5 pm 0.3 µGy (abdomen, radon gas) and 1.1 pm 0.4 µGy (thorax, radon and progeny) for a one-hour reference exposure at a radon activity concentration of 55 kBq m−3. The accumulation of long-retained radon in the abdomen leads to higher dose values at that site than in the thorax. Contrasting prior work, our measurements are performed directly at specific body sites, i.e. thorax and abdomen, which allows for direct spatial distinction of radon kinetics in the body. They show more incorporated and retained radon than current approaches predict, suggesting higher doses. Although obtained only from one person, our data may thus represent a challenge for the barely experimentally benchmarked biokinetic dose assessment model.

Strengthening of Fire Damaged, Light Weight, High Strength Reinforced Concrete Beam Using SIFCON Jacket

This study aims to extrapolate the behavior of lightweight (LECA) high strength concrete beams subjected to high temperatures. the LECA aggregate was utilized as coarse fraction in the reference mixture. a post development process in terms of jacketing the fire damaged beams with SIFCON materials layer was also investigated. In addition to the reference samples, various parameters of concrete beams and conditioning were conducted, namely, fire duration exposure, concrete cover, and SIFCON layer thickness. In details, two concrete cover thickness, half and one-hour fire duration exposure, and two SIFCON layer thicknesses were the main parameters in this study. the thermal gradient through the beam cross section was captured through installing thermocouples sensors embedded inside at various location. The physical and chemical properties were tested for all used materials in this study. Overall, fourteen concrete beam samples were tested for all the three phases (normal or reference, fire damaged samples, and post enhancement with SIFCON jacket). the level of comparison for the tested samples was focused on several parameters are; maximum shear load capacity and corresponded displacement, ductility index, cracking load, initial and secant stiffness, and energy absorption. The experimental test results under the scope of this research have shown significant improvement for the strengthened beams were observed compared with the damaged samples. Moreover, the results have cleared that the strengthened beams, in term of the mentioned indices were recovered as and comparable to the undamaged (reference beam), except the absorption energy. Where further studies and efforts have to be paid to overcome such issue.

Untargeted metabolomics-based response analysis of temperature and insecticide exposure in Aedes aegypti

In this study, we utilized an untargeted NMR metabolomics approach to identify the vector response in terms of metabolic profiling after temperature and insecticide exposure in comparison with the control. Clearly, temperature and insecticide exposure cause changes in the underlying metabolism, and the NMR metabolomic profile enables a direct examination of the immediate response of the vector to cope up with these changes. The present study was designed in four parts: A-Aedes aegypti were exposed to 40 °C for one-hour, DDT-4%, malathion-5%, and deltamethrin-0.05% separately and, part B-D; one-hour exposure at 35 °C and 40 °C temperatures followed by one-hour exposure to insecticide. The resultant metabolite profiles were compared with the control. In response to temperature and insecticide exposure, several metabolites and altered pathways were identified. Citrate, maltose, lipids, Nicotinate, Choline, Pyruvate and β-hydroxybutyrate were found as important components of major biological pathways such as tri-carboxylic acid cycle, branched amino acid degradation, glycolysis/gluconeogenesis, amino acid metabolism, lipid and carbohydrate metabolism, nucleotide PRPP pathway, and phospholipid metabolism. Furthermore, the results also suggest that the changes imposed by exposure to temperature and insecticides individually, are reversed with combined exposure, thus negating the impact of each other and posing a threat to the control of Aedes-borne diseases such as dengue, chikungunya, Zika and yellow fever.

Влияние полихлорбифенилов на показатели биолюминесценции черноморского гребневика Mnemiopsis leidyi A.Agassiz (Ctenophora: Lobata)

The toxic impact of a mixture of polychlorinated biphenyls Aroclor 1254 (PCB) on the luminescence characteristics of the ctenophores Mnemiopsisleidyi A. Agassiz was studied. The control group was kept in an aquarium without a toxicant; experimental individuals were placed in three aquariums with water with PCB concentrations of 1, 10, and 100 µg -1 with an exposure of 15, 30, 40 and 60 minutes. Bioluminescence of M. leidyi was studied using the “Svet” complex. The toxic impact of PCBs caused a decreased amplitude and duration of luminescence at all given concentrations, whereas one-hour exposure to mechanical agitation resulted in a maximum decrease by 35% in the glow duration. At a PCB concentration of 1 μg ∙ L -1 , a maximum decrease in the luminescence intensity by a factor of 20 was observed compared with the control group.

Genotoxic and inflammatory effects of spruce and brown coal briquettes combustion aerosols on lung cells at the air-liquid interface

Solid fuel usage in residential heating and cooking is one of the largest sources of ambient and indoor air particulate matter, which causes adverse effects on the health of millions of peoples worldwide. Emissions from solid fuel combustion, such as biomass or coal, are detrimental to health, but toxicological responses are largely unknown. In the present study, we compared the toxicological responses regarding cytotoxicity, inflammation and genotoxicity of spruce (SPR) and brown coal briquette (BCB) combustion aerosols on human alveolar epithelial cells (A549) as well as a coculture of A549 and differentiated human monocytic cells (THP-1) into macrophages exposed at the air-liquid interface (ALI). We included both the high emissions from the first hour and moderate emissions from the third hour of the batch combustion experiment in one ALI system, whereas, in the second ALI system, we exposed the cells during the whole 4-hour combustion experiment, including all combustion phases. Physico-chemical properties of the combustion aerosol were analysed both online and offline. Both SPR and BCB combustion aerosols caused mild cytotoxic but notable genotoxic effects in co-cultured A549 cells after one-hour exposure. Inflammatory response analysis revealed BCB combustion aerosols to cause a mild increase in CXCL1 and CXCL8 levels, but in the case of SPR combustion aerosol, a decrease compared to control was observed.

Детекция окислительного стресса в артериальных эндотелиальных клетках человека при воздействии кальций-фосфатных бионов

Введение. Кальций-фосфатные бионы (КФБ) формируются в организме человека при перенасыщении сыворотки ионами кальция и фосфора и вызывают дисфункцию эндотелия, однако молекулярные механизмы нарушения функционирования эндотелия при воздействии КФБ не ясны. Цель исследования - выяснение роли кальций-фосфатных бионов различной формы в развитии окислительного стресса в артериальных эндотелиальных клетках (ЭК) человека. Методика. Для детекции окислительного стресса к конфлюэнтным культурам первичных ЭК коронарной и внутренней грудной артерии человека добавляли равные концентрации КФБ сферической или игольчатой формы (СКФБ и ИКФБ соответственно) с последующим культивированием в течение 1 и 4 ч, добавлением флюоресцентных индикаторов окислительного стресса MitoSOX Red и CellROX Green и конфокальной микроскопией. Измеряли концентрацию продуктов перекисного окисления липидов в культуральной жидкости через 24 ч экспозиции эндотелиальных клеток КФБ. Анализ нейтрализации цитотоксических эффектов перекисного окисления липидов проводили путем добавления к ЭК супероксиддисмутазы и каталазы на 4 или 24 ч (одновременно с КФБ). Для сравнения механизмов клеточной гибели при воздействии СКФБ и ИКФБ анализировали цитотоксичность обоих типов бионов при одновременном воздействии лизосомального ингибитора бафиломицина А1. Результаты. Значимого увеличения генерации активных форм кислорода (АФК) в результате экспозиции СКФБ (независимо от линии ЭК и продолжительности экспозиции) не было выявлено. В то же время наблюдалось повышение генерации супероксида через 4 ч, а иных свободных радикалов через 1 ч после добавления ИКФБ к ЭК. Предварительная нейтрализация АФК супероксиддисмутазой и каталазой частично защищала ЭК от индуцируемой ИКФБ гибели. При этом добавление бафиломицина А1 к ЭК частично защищало их от гибели только при воздействии СКФБ, но не ИКФБ. Заключение. Гибель ЭК при воздействии СКФБ происходит в результате первичного повреждения лизосом, а при воздействии ИКФБ - в первую очередь вследствие окислительного стресса. Background. Calcium phosphate bions (CPB) form in the human blood upon its supersaturation with calcium and phosphate and provoke endothelial dysfunction; however, the molecular mechanisms of these pathological processes remain unclear. Aim. To elucidate the role of differently shaped CPBs in induction of oxidative stress in human arterial endothelial cells (Ecs). Methods. For detection of oxidative stress, equal concentrations of spherical CPB (CPB-S) or needle-shaped CPB (CPB-N) were added to confluent cultures of primary human coronary artery and internal thoracic artery ECs for 1 and 4 h; this was followed by MitoSOX Red and CellROX Green staining and subsequent confocal microscopy. Concentration of thiobarbituric acid-reactive substances was measured in the EC culture supernatant at 24 h of the CPB exposure. The lipid peroxidation cytotoxicity was neutralized by adding superoxide dismutase and catalase to ECs for 4 or 24 h. To compare cell death subroutines induced by CPB-S and CPB-N, the effect of bafilomycin A1, a lysosomal inhibitor, on CRB cytotoxicity was studied. Results. No increase in reactive oxygen species generation was observed in the CPB-S exposure, regardless of the EC line and exposure duration. However, addition of CPB-N to ECs increased the production of superoxide and other free radicals after four- and one-hour exposure, respectively. Prior neutralization of reactive oxygen species with superoxide dismutase and catalase partially protected ECs from CPB-N- but not CPB-S-induced death while bafilomycin A1, vice versa, protected ECs from CPB-S- but not CPB-N-induced death. Conclusion. CPB-S cause cell death due to primary damage of lysosomes whereas CPB-N induce apoptosis due to oxidative stress.

The Association Between Ferritin and Vitamin D Levels in Premenopausal Fibroid Uterus Cases With Anemia.

ObjectiveThe present study aimed to evaluate the association between serum ferritin and vitamin D levels in fibroid uterus cases presenting with anemia.MethodsSixty premenopausal women with uterine fibroids (30 associated with anemia and 30 without anemia) were enrolled as cases and control. All participants were evaluated on the basis of a questionnaire, which included queries related to obstetric, medical, and sociodemographic history. Peripheral blood smear, complete blood count (CBC), hemoglobin (Hb), and serum ferritin concentration were measured by a fully automated analyzer, and 25(OH) vitamin D level was measured by enzyme-linked immunosorbent assay (ELISA).ResultsThere was a significant difference in ferritin levels between cases and control (p<0.001). The exposure to sunlight was moderate (one-hour exposure) in all subjects, eliminating the confounding effect of sunlight exposure influencing vitamin D levels. The median vitamin D level in cases was 5.0 ng/ml [interquartile range (IQR): 4.8], and that in control was 18.4 ng/ml (IQR: 7.9; p<0.001). A strong positive correlation of (r)=0.616 (p<0.001) was found between serum ferritin and vitamin D levels.ConclusionFibroid uterus cases with anemia are more prone to vitamin D deficiency as compared to cases without anemia. Vitamin D estimation in fibroid uterus cases presenting with anemia would be useful for better patient management.