Longer Duration Of Exposure Research Articles

Influence of antenatal glucocorticoid on preterm lamb diaphragm.

BackgroundPregnant women at a high risk of preterm delivery receive glucocorticoids to accelerate fetal lung maturation and surfactant synthesis. However, the effect of antenatal steroids on the developing diaphragm remains unclear. We hypothesized that maternal betamethasone impairs the fetal diaphragm, and the magnitude of the detrimental effect increases with longer duration of exposure. We aimed to determine how different durations of fetal exposure to maternal betamethasone treatment influence the fetal diaphragm at the functional and molecular levels.MethodsDate-mated merino ewes received intramuscular injections of saline (control) or two doses of betamethasone (5.7 mg) at an interval of 24 h commencing either 2 or 14 days before delivery. Preterm lambs were killed after cesarean delivery at 121-day gestational age. In vitro contractile measurements were performed on the right hemidiaphragm, whereas molecular/cellular analyses used the left costal diaphragm.ResultsDifferent durations of fetal exposure to maternal betamethasone had no consistent effect on the protein metabolic pathway, expression of glucocorticoid receptor and its target genes, cellular oxidative status, or contractile properties of the fetal lamb diaphragm.ConclusionThese data suggest that the potential benefits of betamethasone exposure on preterm respiratory function are not compromised by impaired diaphragm function after low-dose maternal intramuscular glucocorticoid exposure.

Lethal and behavioral impacts of diesel and fuel oil on the Antarctic amphipod Paramoera walkeri.

Toxicity testing with Antarctic species is required for risk assessment of fuel spills in Antarctic coastal waters. The lethal and sublethal (movement behavior) sensitivities of adults and juveniles of the Antarctic amphipod Paramoera walkeri to the water accommodated fractions (WAFs) of 3 fuels were estimated in extended-duration tests at -1 °C to 21 d. Response of P. walkeri for lethal hydrocarbon concentrations was slow, with 50% lethal concentrations (LC50s) first able to be estimated at 7 d for adults exposed to Special Antarctic Blend diesel (SAB), which had the highest hydrocarbon concentrations of the 3 fuel WAFs. Juveniles showed greater response to marine gas oil (MGO) and intermediate residual fuel oil (IFO 180) at longer exposure durations and were most sensitive at 21 d to IFO 180 (LC50 = 12 μg/L). Adults were initially more sensitive than juveniles; at 21 d, however, juveniles were more than twice as sensitive as adults to SAB (LC50 = 153 μg/L and 377 μg/L, respectively). Significant effects on movement behavior were evident at earlier time points and lower concentrations than was mortality in all 3 fuel WAFs, and juveniles were highly sensitive to sublethal effects of MGO. These first estimates of Antarctic amphipod sensitivity to diesel and fuel oils in seawater contribute to the development of ecologically relevant risk assessments for management of hydrocarbon contamination in the region. Environ Toxicol Chem 2017;36:2444-2455. © 2017 SETAC.

Exogenous attention to fear: Differential behavioral and neural responses to snakes and spiders

Research has consistently shown that threat stimuli automatically attract attention in order to activate the defensive response systems. Recent findings have provided evidence that snakes tuned the visual system of evolving primates for their astute detection, particularly under challenging perceptual conditions. The goal of the present study was to measure behavioral and electrophysiological indices of exogenous attention to snakes, compared with spiders – matched for rated fear levels but for which sources of natural selection are less well grounded, and to innocuous animals (birds), which were presented as distracters, while participants were engaged in a letter discrimination task. Duration of stimuli, consisting in a letter string and a concurrent distracter, was either presented for 180 or 360ms to explore if the stimulus duration was a modulating effect of snakes in capturing attention. Results showed a specific early (P1) exogenous attention-related brain potential with maximal amplitude to snakes in both durations, which was followed by an enhanced late attention-related potential (LPP) showing enhanced amplitudes to spiders, particularly under the longer exposure durations. These results suggest that exogenous attention to different classes of threat stimuli follows a gradual process, with the most evolutionary-driven stimulus, i.e., snakes, being more efficient at attracting early exogenous attention, thus more dependent on bottom-up processes.

SENSITIVITY OF PIGMENT CONTENT OF BANANA AND ORCHID TISSUE CULTURE EXPOSED TO EXTREMELY LOW FREQUENCY ELECTROMAGNETIC FIEL

<p>Natural exposure of extremely low frequency electromagnetic field (ELF-EMF) occurs in the environment and acts as one of the abiotic factors that affect the growth and development of organisms. This study was conducted to determine the effect of ELF-EMF on the tissue cultured banana and slipper orchid chlorophyll content as one of the indicators in measuring plant photosynthetic capacity. Four days old banana (Musa sp. cv. Berangan) corm and seven days old slipper orchid (Paphiopedilum rothschildianum) cultures were exposed to 6 and 12 mT ELF-EMF generated by controllable ELF-EMF built up machine for 0.5, 1, 2 and 4 hours. After exposure, the banana and orchid cultures were incubated at 25° C for 8 and 16 weeks, respectively. The results showed that the ELF-EMF exposure had different effects on banana and slipper orchid cultures though both plant species belong to monocotyledon. The highest increase in chlorophyll content on banana was resulted by the high intensity and long duration of ELF-EMF exposure (12 mT for 4 hours), whereas on slipper orchid the modest and short duration of ELF-EMF exposure produced the most excessive chlorophyll content. Different ELF-EMF exposures (12 mT for 4 hours and 6 mT for 30 minutes) had potential to be applied on each plant to improve in vitro plant (banana and slipper orchid, respectively) growth. The increased chlorophyll and carotene/xanthophyll content on banana indicated that the banana was more tolerant to ELF-EMF exposure compared to slipper orchid. </p>

The Effect of Ultraviolet Radiation on the Hyperelastic Behavior of Polyurea

Polyurea is widely used in military and civilian applications, where long durations of exposure to the sun is common. Extended ultraviolet exposure can deteriorate the mechanical performance of the material to suboptimal levels. This study reports on the hyperelastic behavior of polyurea as a function of exposure duration to ultraviolet radiation. Initially, five sets of samples were continuously exposed to ultraviolet radiation for different durations up to 15 weeks. An additional set of samples were kept unexposed to report on the properties of an as-cast polyurea control. The samples were then loaded uniaxially in tension under a quasi-static loading rate (\(\dot{\epsilon }=0.0127{s}^{-1}\)) using a standard load frame. All exposed samples exhibited incremental color changes, which ranged from transparent yellow in virgin samples to opaque tan after 15 weeks of exposure. Changes in color were observed as early as 3 weeks of ultraviolet exposure. In addition to discoloration, crazing developed in all samples for exposure durations of 3 weeks and beyond. The size of the cracks increased as the duration of exposure continued. Postmortem examination indicated the initial microcracks grew due to loading and were visible to the naked eye. Discoloration and crazing were attributed to the formation of a thin ultraviolet-degraded layer due to the interaction of oxygen and ultraviolet light with the chromophoric groups in the polyurea macromolecule. The hyperelastic behavior was studied by fitting the stress–strain data into a four-term Ogden model. The overall hyperelastic behavior of polyurea remained unchanged even after 15 weeks of continuous ultraviolet exposure, where no permanent failure (except the ultraviolet-induced cracks) was recorded at the gauge length up to 250% strain. The values of the fitting parameters were nearly identical, supporting the conclusion of the insensitivity of polyurea hyperelastic behavior to ultraviolet radiation.

Cytotoxic Evaluation of Some Fused Pyridazino- and Pyrrolo-quinazolinones Derivatives on Melanoma and Prostate Cell Lines

Background:Quinazolinon as an important class of heterocycles is attractive in medicinal research areas due to their wide range of biological effects. Cytotoxic activities of the quinazolinone derivatives in various cell lines including: HeLa, L1210 (mouse lymphocytic leukemia) and HT29 (human colon adenocarcinoma) were reported.Materials and Methods:In this study, a number of newly made tricycles quinazolinone derivatives such as fused pyridazino-quinazolinones and fused pyrrolo-quinazolinones were evaluated on two cancerous cell lines, melanoma (B16F10) and prostate (PC3) using the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide colorimetric assay.Results:The results of cytotoxicity evaluations indicated that almost all of the compounds at the concentrations of 10 and 100 μM showed significant differences in viability in comparison with negative control at 48 h exposure (P < 0.05). However, during 24 h exposure some of the compounds showed cytotoxicity activity.Conclusion:Results showed that both cell lines were sensitive to synthesized compounds and longer duration of exposure (48 h) had better results compared to that of 24 h screening.

An Own-Age Bias in Recognizing Faces with Horizontal Information.

Horizontal information, as a result of a selective filtering process, is essential in younger adults’ (YA) ability to recognize human faces. Obermeyer et al. (2012) recently reported impaired recognition of faces with horizontal information in older adults (OA) suggesting age-variant processing. Two yet unconsidered factors (stimulus age and exposure duration) that may have influenced previous results, were investigated in this study. Forty-seven YA (18–35 years) and 49 OA (62–83 years) were tested in a 2 × 2 × 2 × 2 mixed design with the between-subjects factors age group (YA vs. OA) and stimulus age (young faces vs. older faces) and the within-subjects factors filter [filtered (HF) faces vs. unfiltered faces (UF)] and exposure duration (0.8 s vs. 8 s). Subjects were presented morph videos between pairs of faces: a starting face gradually merged into either the previously encoded target face or a control face. As expected, results showed an increase in recognition sensitivity (d′) with longer exposure duration in YA with both younger and older HF faces. OA, however, were unable to recognize filtered young faces not even with increased exposure duration. Furthermore, only elderly participants showed more accurate recognition with faces of their own age relative to other-age faces (own-age bias, OAB). For YA no OAB was observed. Filtered face recognition was significantly correlated with unfiltered recognition in YA but not in OA. It is concluded, that processing of horizontal information changes at a higher age. Presenting filtered or unfiltered faces both targets convergent face-specific processing only in YA but not in OA.

Safety of Enalapril in Infants Admitted to the Neonatal Intensive Care Unit.

Enalapril is used to treat hypertension and congestive heart failure in infants. However, enalapril is not labeled for neonates, and safety data in infants are sparse. To evaluate the safety of enalapril in young infants, we conducted a retrospective cohort study of infants who were exposed to enalapril in the first 120days of life and were cared for in 348 neonatal intensive care units from 1997 to 2012. We determined the proportion of exposed infants who developed adverse events, including death, hypotension requiring pressors, hyperkalemia, and elevated serum creatinine. Using multivariable logistic regression, we examined risk factors for adverse events, including postnatal age at first exposure, exposure duration, gestational age group, small for gestational age status, race, sex, 5-min Apgar score, and inborn status. Of a cohort of 887,910 infants, 662 infants (0.07%) were exposed to enalapril. Among exposed infants, 142 infants (21%) suffered an adverse event. The most common adverse event was hyperkalemia (13%), followed by elevated serum creatinine (5%), hypotension (4%), and death (0.5%). Significant risk factors for adverse events included postnatal age <30days at first exposure and longer exposure duration. This study is the largest to date examining the safety of enalapril in young term and preterm infants without significant structural cardiac disease.

Impact of acute and chronic inhalation exposure to CdO nanoparticles on mice.

Cadmium nanoparticles can represent a risk in both industrial and environmental settings, but there is little knowledge on the impacts of their inhalation, especially concerning longer-term exposures. In this study, mice were exposed to cadmium oxide (CdO) nanoparticles in whole body inhalation chambers for 4 to 72h in acute and 1 to 13weeks (24h/day, 7days/week) in chronic exposure to investigate the dynamics of nanoparticle uptake and effects. In the acute experiment, mice were exposed to 2.95×106 particles/cm3 (31.7μg CdO/m3). The same concentration and a lower one (1.18×106 particles/cm3, 12.7μg CdO/m3) were used for the chronic exposure. Transmission electron microscopy documented distribution of nanoparticles into all studied organs. Major portion of nanoparticles was retained in the lung, but longer exposure led to a greater relative redistribution into secondary organs, namely the kidney, and also the liver and spleen. Accumulation of Cd in the lung and liver occurred already after 24h and in the brain, kidney, and spleen after 72h of exposure, and a further increase of Cd levels was observed throughout the chronic exposure. There were significant differences in both Cd accumulation and effects between the two exposure doses. Lung weight in the higher exposure group increased up to 2-fold compared to the control. Histological analyses showed dose-dependent alterations in lung and liver morphology and damage to their tissue. Modulation of oxidative stress parameters including glutathione levels and increased lipid peroxidation occurred mainly after the greater chronic exposure. The results emphasize risk of longer-term inhalation of cadmium nanoparticles, since adverse effects occurring after shorter exposures gradually progressed with a longer exposure duration.

Pilot Study of Accelerated Low-Frequency Right-Sided Transcranial Magnetic Stimulation for Treatment-Resistant Depression.

Repetitive transcranial magnetic stimulation (rTMS) is an effective option for treatment-resistant depression but requires prolonged repeated daily treatments for 4 to 6 weeks. Pilot studies have showed the possibility of accelerating rTMS safely and efficaciously but thus far only investigated high-frequency left-sided rTMS. We sought to investigate the safety and efficacy of accelerated low-frequency right-sided rTMS. Our study was an open label accelerated rTMS pilot in 7 treatment-resistant patients (4 unipolar, 3 BP). Accelerated rTMS was given over the right dorsolateral prefrontal cortex at 120% of resting motor threshold at 1 Hz, and 900 pulses were delivered per session. A single rTMS treatment was administered on the first day to test for tolerability, followed by 5 rTMS sessions a day for 2 days, then 7 days of daily rTMS sessions. The total course consisted of 16,200 pulses across 18 sessions given over 10 consecutive weekdays. The primary outcomes of interest were self- and clinician-rated depression scores (BDI-II and MADRS). All patients successfully and safely completed the accelerated rTMS treatment. MADRS scores decreased significantly by the third day of treatment and BDI II scores by the end of the 10-day treatment. No patients achieved response or remission. Accelerated low-frequency right-sided rTMS was a safe and possibly efficacious treatment for treatment-resistant depression. More research is recommended, including a controlled trial with longer duration of exposure, to establish the efficacy of left- and right-sided accelerated rTMS.

Efficiency and safety of SGLT2 inhibitors

Background According to statistical data of the International Diabetes Federation in 2015 the number of diabetes mellitus (DM) patients was 415 millions. By 2040, projected number of patients will be about 642 millions. Despite the large arsenal of antidiabetic drugs, hypoglycemic means search with maximum efficiency and minimal side effects such as weight gain and hypoglycemia level are continued. Purpose The study of the efficacy and safety of new classes of hypoglycemic drugs due to analysis of publications in medical databases. Results SGLT2 inhibitors are a group of oral hypoglycemic drugs which therapeutic target are kidneys. The mechanism of action is glucose and sodium symport blockage, which ensures reduction of glucose reabsorption and normalize glycaemia. Glucose toxicity reduction at the usage of these drugs is manifested in the recovery of the pancreas beta cells sensitivity, thus increasing insulin synthesis, and sensitization of peripheral tissues to insulin action. The usage of SGLT2 inhibitors not only leads to blood glucose lowering but also to shift the energy balance in a negative way that creates additional benefits in DM patients with obesity. Side effects of SGLT2 inhibitors therapy include urinary tract and genital infections. These drugs also have a diuretic effect, which can lead to the dehydration or hypotension. Some researches highlight the risks for bone fractures. SGLT2 inhibitors increase concentrations of phosphate in serum, probably via increased tubular reabsorption, which has the potential to adversely affect bone. Furthermore, SGLT2 inhibitors increase concentrations of parathyroid hormone, which enhance bone resorption. The question of carcinogenesis is still controversial. Studies have implied that the SGLT receptor may play a role in glucose uptake in many cancers. SGLT2 inhibitors increase the risk for urinary tract infections, which could increase the risk for bladder cancer. Human trials showed excess cases of female breast, male bladder cancer; but they did not reach statistical significance. New data for dapagliflozin suggested that these excess cancers may be due to early diagnosis rather than increased incidence. Canagliflozin rat studies suggested increased risk for renal, adrenal, and Leydig cell tumors, but phase 3 clinical trials do not support increased incidence of these cancers in humans. Evidence for the link between SGLT2 inhibitor use and cancer risk is not conclusive and remains a safety issue. Studies with larger sample size, longer exposure duration, and use of SGLT2 inhibitors in different ethnicities are needed. In May 2015, the FDA issued a warning that SGLT2 inhibitors may lead to ketoacidosis. The decline in circulating insulin levels results in a lowering of the antilipolytic activity of insulin and consequent stimulation of the production of free fatty acids, which are converted to ketone bodies by β-oxidation in the liver. Obviously, not all individuals who take SGLT2 inhibitors are at high-risk for euglycemic ketoacidosis. SGLT2 inhibitors have the potential to reduce cardiovascular risk in DM patients not only through effects on glycemic control, but also via beneficial effects on body weight, blood pressure, lipids. Large studies are underway to elucidate the effects of SGLT2 inhibitors on these outcomes, the results of which are eagerly awaited. Conclusions The resume of the data is ambiguous. On one side, this class of drugs offers new opportunities in the treatment of DM type 2: first of all, a new, insulin independent mechanism of action, absence of negative effect on body weight, favorable pharmacokinetic properties and overall good tolerance. On the other side, mechanism of action of SGLT2 inhibitors is directed to the clinical manifestations of diabetes and not to the cause. Listed, identified and investigated nephroprotective and cardioprotective effects, data on the effects on bone, lack of carcinogenic risk are required confirmation in the long-term. The results of new clinical and epidemiological studies should identify the benefit/risk ratio of a new class of antidiabetic agents in the long-term, and its place in the treatment of patients with DM type 2.

Tyler asbestos workers: A mortality update in a cohort exposed to amosite

ABSTRACTThe Tyler asbestos plant produced pipe insulation from 1954 to 1972 and exclusively used amosite asbestos. There were 1130 former workers of this plant during the period of operation. A death certificate mortality analysis was published regarding this plant in 1998 for the period through 1993. This study represents an update of the mortality analysis with additional certificates collected for deaths occurring through 2011.Searches of the National Death Index database were conducted in 2004 and again in 2013. At the time of the latter search, only deaths occurring through 2011 were available. In total, 265 distinct additional death certificates were secured and added to 304 available from the original study. After the new certificates were coded (ICD-9), data were analyzed using the Centers for Disease Control and Prevention Life Table Analysis System (LTAS) and standard mortality ratios (SMR) generated with 95% confidence limits (CL). LTAS constructs cause-specific mortality rates by age, gender, race, and person-time at risk, and compares observed rates with a referent population in order to derive SMR. A significant excess number of deaths due to nonmalignant respiratory disease (asbestosis) and from select malignant neoplasms were identified. There were in total 23 mesothelioma deaths (4% of deaths), with 16 pleural and 7 peritoneal. The SMR for malignant neoplasms of the trachea, bronchus, and lung was 244 (with 95% CL 196, 300), suggesting that exposed workers from this cohort were nearly 2.5-fold (244 %) more likely to die from this cause as the general referent population. The analysis also showed that exposures of short duration (<6 mo) produced significantly elevated SMR for all respiratory cancers, lung cancer, and pleural mesothelioma. There was a significant difference in median duration of exposure for mesothelioma types, confirming association of peritoneal mesothelioma with longer duration of exposure. Deaths due to intestinal cancer (predominantly colon; not including rectum) were also found in excess. The mortality experience of the Tyler cohort continues to be followed with great interest, given the exclusivity of exposure to amosite. Data confirm the inherent pathogenicity of this fiber type for nonmalignant disease as well as select cancers, particularly relevant given the importance of this amphibole’s use in the United States.

Thin Slice Impressions: How Advertising Evaluation Depends on Exposure Duration

This research demonstrates the importance of thin slices of information in ad and brand evaluation, with important implications for advertising research and management. Three controlled experiments, two in the behavioral lab and one in the field, with exposure durations ranging from very brief (100 msec) to very long (30 sec), demonstrate that advertising evaluation critically depends on the duration of ad exposure and on how ads convey which product and brand they promote, but in surprising ways. The experiments show that upfront ads, which instantly convey what they promote, are evaluated positively after brief but also after longer exposure durations. Mystery ads, which suspend conveying what they promote, are evaluated negatively after brief but positively after longer exposure durations. False front ads, which initially convey another identity than what they promote, are evaluated positively after brief exposures but negatively after longer exposure durations. Bayesian mediation analysis demonstrates that the feeling of knowing what the ad promotes accounts for these ad-type effects on evaluation.

Abstract 606: Similar 3D pharmacodynamic (3D-PD) responses of human tumor spheroids and xenografts to topoisomerase 1 inhibitor-induced DNA damage

Abstract Three-dimensional (3D) cultures have been proposed as higher fidelity models of in vivo tumors than 2D cultures. To determine whether this idea extends to drug pharmacodynamics, we examined whether 3D cultures of the human melanoma line A375 (grown as tumor spheroids) could replicate the timing and magnitude of the nuclear γH2AX response to the topoisomerase 1 inhibitor, topotecan observed in A375 tumor xenografts (Kinders et al, Clin Can Res 2010). The appearance of γH2AX-positive nuclear foci has been used as a biomarker for drug- and radiation-induced double-strand breaks in DNA; we reported previously that treatment of nu/nu mice harboring A375 xenografts with a single-dose of topotecan induced nuclear γH2AX foci in a dose- and time-dependent manner, which peaked 4 hours after drug administration. A375 spheroids were generated by seeding cells into ULA U-bottom plates; 4 hours of exposure to 0.1 μM topotecan elicited a γH2AX signal in these 3D cultures while cell viability and intracellular ATP levels remained unchanged, indicating a DNA damage repair response at the maximally tolerated topotecan concentration for human hematopoietic cells (Erickson-Miller et al, Can Chemo Pharmacol 2009). Extending drug exposure to 24 hours caused substantial loss of viable cells (calcein AM+) and 50% decline in ATP levels but no further increase in γH2AX. In contrast, the HT29 tumor line was refractory to topotecan in vivo, and exposing 3D cultures of HT-29 spheroids to 0.1 μM topotecan for 24 hours elicited a strong nuclear γH2AX biomarker response in only a small fraction of cells at the surface of the spheroids. Longer exposure durations or supra-pharmacological concentrations (1 μM) of topotecan were required to achieve a strong nuclear γH2AX response in HT-29 spheroids. These results support the hypothesis that the 3D pharmacodynamics (PD) of drug response is similar to PD drug response in vivo for the camptothecin class of topoisomerase 1 inhibitors. Funded by NCI Contract No. HHSN261200800001E. Citation Format: David M. Evans, Rene Delosh, Julie Laudeman, Chad Ogle, Russell Reinhart, Michael Selby, Silvers Thomas, Robert Kinders, Tony Navas, Scott Lawrence, Anne Monks, Annamaria Rapisarda, Ralph E. Parchment, James H. Doroshow, Beverly Teicher. Similar 3D pharmacodynamic (3D-PD) responses of human tumor spheroids and xenografts to topoisomerase 1 inhibitor-induced DNA damage. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 606.

Abstract 3428: Domestic livestock exposure and lung cancer risk among non-smoking women in Xuanwei, China

Abstract Background: Lung cancer rates of women in Xuanwei and Fuyuan, rural counties located in the Yunnan Province, are among the highest in China, even though most women there are non-smokers. The unusually high lung cancer rates are mainly attributed to smoky (i.e. bituminous) coal exposures. Many households there and in other rural parts of China have raised animals such as pigs, cows, horses, chickens and ducks in close proximity to their homes. It is hypothesized that contact with animals increases the risk of infection with potentially carcinogenic pathogens. However, findings on the association between livestock and poultry exposures and lung cancer risk, mostly from occupational studies, have been inconsistent. Objective: To investigate the association between livestock and poultry exposures and lung cancer risk in a general population of non-smoking women who lived in close proximity to livestock and poultry in a rural area in China. Methods: A hospital-based case-control study among non-smoking women was conducted in Xuanwei and Fuyuan counties in China between March 2006 and July 2013. A total of 1,074 lung cancer cases and 977 hospital-based cancer-free controls were enrolled. Exposure to livestock and poultry, including the animal type (pigs, cows/horses, chickens, ducks) and total number of years an individual was exposed to each animal type, was obtained by questionnaire. Reference groups for the analysis were either never-exposed, or never-exposed combined with those with less than the median years of exposure, depending on the prevalence of exposure to each animal. Logistic regression was used to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) of the association between livestock and poultry exposures and lung cancer risk with adjustment for potential confounders, such as lifetime amount of smoky coal used and passive smoking. Results: Individuals with above the median number of years of exposure to pigs (OR = 1.61, 95% CI = 1.19-2.17) and chickens (OR = 1.49, 95% CI = 1.12-1.99) had increased lung cancer risk, compared to those who had less than the median years of exposure. Compared to those who were never exposed, the risk of lung cancer increased with longer duration of exposure to cows/horses (&amp;lt;median years of exposure: OR = 1.33, 95% CI = 1.00-1.77; ≥median years of exposure: OR = 1.38, 95% CI = 1.03-1.86). The significant associations for pigs and cows/horses persisted after adjusting for other animal exposures in the same model. Conclusions: Exposure to certain animals was significantly associated with increased lung cancer risk, suggesting that infectious agents may play a role in the etiology of lung cancer among non-smoking women in this region. However, due to the fact that this study was conducted in an area with a high risk of lung cancer due to the use of solid fuels for heating and cooking, we cannot rule out residual confounding. Citation Format: Wei Jie Seow, Wei Hu, Roel Vermeulen, George Downward, Jihua Li, Jun Xu, Jun He, Fusheng Wei, Guoping Wu, Nathaniel Rothman, Robert S. Chapman, Qing Lan. Domestic livestock exposure and lung cancer risk among non-smoking women in Xuanwei, China. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 3428.

Prostate-specific antigen and its derivatives in young adults occupationally exposed to quarry pollutants in southeastern Nigeria

ABSTRACTTo evaluate the level of total prostate-specific antigen (PSA) and effect of duration of exposure to pollutants in quarry workers, 5 mls of blood sample was collected from participants: 72 male quarry workers exposed to quarry pollutants and 72 unexposed controls. PSA estimations were done using the principle of ELISA. Mean total PSA, free PSA, and free-total PSA ratio levels of quarry workers did not differ from those of controls and was below the cutoff for the risk of prostate diseases. Higher mean total PSA and free PSA were observed in workers exposed for > 3 years compared to the unexposed control and workers exposed for ≤ 3 years. Age-adjusted linear regression indicated significant association (R = 0.515; p < .001) between the duration of exposure and total PSA level in quarry workers. This study suggests that longer duration of exposure to the quarry pollutants may elevate PSA level if precautions are not taken to minimize dose of exposure.

Performance evaluation of two N95 filtering-facepiece respirators on decomposition products of sulfur hexafluoride

To assess the filtration efficiency of two N95 filtering-facepiece respirators (FFRs) for the decomposition products of sulfur hexafluoride (SF6). Two types of N95 FFRs (the particulate and the acid-proof respirators) were selected in this study. The decomposition products of SF6, including particles, hydrogen fluoride (HF) and sulfur dioxide (SO2) , were measured under experimental condition by using TSI PortaCount Plus, fluorine ion-selective electrodes and spectrophotometer separately. The filtration efficiency was then calculated and compared. Both two models of N95 respirators had lowest filtration efficiency larger than 95% for particles under airflow ranged from 10 to 95 L/min. When exposed to different concentrations of HF (low: 0.00~1.99 mg/m(3), middle: 2.00~3.99 mg/m(3), high: >4 mg/m(3)) , the acid-proof N95 respirator was more effective than the particulate respirator (P<0.05) with a filtration efficiency of 98.83%, 99.08%, and 99.03% versus 48.44%, 45.71%, and 47.31%. For four SO2 concentration ranges (0.00~2.49 mg/m(3), 2.50~4.99 mg/m(3), 5.00~9.99 mg/m(3), and >10.00 mg/m(3)) , the acid-proof respirator showed a high filtration efficiency within exposure to 1.5 hours: 95.73%, 98.67%, 98.14%, and 97.78%, respectively, when exposure duration extended to 4 hours, the filtration efficiency of the acid-proof respirator decreased to 91.97%, 82.28%, 70.12%, and 58.56%, respectively. Both the particulate and the acid-proof N95 FFRs met national standards on the particulate filtration efficiency. The acid-proof N95 respirator demonstrates to be more effective in filtering HF and SO2 than the particulate respirator. The filtration efficiency could decrease to an unsafe condition under longer exposure duration, timely replacement of respirator is recommended at the workplace.

Propofol depresses cisplatin cytotoxicity via the inhibition of gap junctions.

The general anesthetic, propofol, affects chemotherapeutic activity, however, the mechanism underlying its effects remains to be fully elucidated. Our previous study showed that tramadol and flurbiprofen depressed the cytotoxicity of cisplatin via the inhibition of gap junction (GJ) intercellular communication (GJIC) in connexin (Cx)32 HeLa cells. The present study investigated whether the effects of propofol on the cytotoxicity of cisplatin were mediated by GJ in U87 glioma cells and Cx26‑transfected HeLa cells. Standard colony formation assay was used to determine the cytotoxicity of cisplatin. Parachute dye coupling assay was used to measure GJ function, and western blot analysis was used to determine the expression levels of Cx32. The results revealed that exposure of the U87 glioma cells and the Cx26-transfected HeLa cells to cisplatin for 1h reduced clonogenic survival in low density cultures (without GJs) and high density cultures (with GJs). However, the toxic effect was higher in the high density culture. In addition, pretreatment of the cells with propofol significantly reduced cisplatin‑induced cytotoxicity, but only in the presence of functional GJs. Furthermore, propofol significantly inhibited dye coupling through junctional channels, and a long duration of exposure of the cells to propofol downregulated the expression levels of Cx43 and Cx26. These results demonstrated that the inhibition of GJIC by propofol affected the therapeutic efficacy of chemotherapeutic drugs. The present study provides evidence of a novel mechanism underlying the effects of analgesics in counteracting chemotherapeutic efficiency.

Treating pediatric plaque psoriasis: challenges and solutions.

Psoriasis is a T-lymphocyte-mediated chronic inflammatory disorder involving the skin and joints. Nearly 3.5% of the population has been diagnosed to have psoriasis. In a dermatology department, almost one-third of psoriasis patients are in the pediatric age group. With an annual prevalence of up to 0.71%, childhood psoriasis can now be regarded as a frequently seen chronic inflammatory skin disorder having a significant impact on the quality of life. Based on the age of onset, psoriasis in children can be broadly classified as infantile psoriasis that can be mostly self-limited, psoriasis having an early onset, which needs specific treatment, and psoriasis that is associated with arthritis. Treating a child with psoriasis is a challenge, considering the physical development, body metabolism, rate of cutaneous absorption, and metabolism of drugs, which are quite different from those of the adults. The long duration of sun exposure for the rest of their life makes it more demanding while considering phototherapy in children. Long-term treatment of psoriasis, with phototherapy or drugs, needs critical evaluation in children. Hence, a thorough understanding of the disease in all its aspects will certainly help manage childhood psoriasis better. Timely diagnosis and adequate management not only arrest progression but also minimize the psychological burden caused by the disease, averting disfiguring states and evolution into a metabolic syndrome.

Use of high concentrations of carbon dioxide for stunning rabbits reared for meat production

&lt;p&gt;Abstract: An investigation was performed to determine whether high concentrations of carbon dioxide (CO&lt;sub&gt;2&lt;/sub&gt;) at 70-98% in atmospheric air are a suitable alternative for stunning rabbits compared to conventional approaches such as electronarcosis. Aversion to the gas and efficacy in causing prolonged unconsciousness and death were studied in a total of 480 rabbits by means of behavioural parameters, physiological indicators (presence of rhythmic breathing and corneal reflex) and electroencephalography (EEG, brain function). The use of any of the 4 studied concentrations of the gas caused more nasal discomfort and vocalisations than the use of atmospheric air (P&amp;lt;0.001). EEG activity confirmed that loss of posture is a good indicator of the onset of unconsciousness in rabbits exposed to CO&lt;sub&gt;2&lt;/sub&gt;, occurring earlier (P&amp;lt;0.05) at 90 and 98% than at 70 and 80%. Rabbits showed signs of aversion for 15 s before the onset of unconsciousness, which occurred around 30 s after the beginning of the exposure to the gas, similar to species such as swine in which high concentrations of CO&lt;sub&gt;2&lt;/sub&gt; are also used for stunning. CO&lt;sub&gt;2&lt;/sub&gt; at 80 to 98% is suggested as a reasonable concentration range to induce a long state of unconsciousness and death in rabbits, while 70% CO&lt;sub&gt;2&lt;/sub&gt; is not recommended because it requires too long duration of exposure (more than 360 s) to ensure effectiveness. Despite the advantages in terms of pre-stun handling and irreversibility, CO&lt;sub&gt;2&lt;/sub&gt; is not free of animal welfare concerns. In consequence, a debate is necessary to ascertain if CO&lt;sub&gt;2&lt;/sub&gt; can be considered a suitable alternative to stun rabbits, considering the advantages and drawbacks cited, quantified in the present study as 15 s of aversion (nasal discomfort and vocalisations) before losing posture.&lt;/p&gt;