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1.
N. Cody Schaal Raushan A. Salaam Michael Stevens Alex Stubner 《Journal of occupational and environmental hygiene》2019,16(5):329-335
The purpose of this investigation was to characterize noise levels in spaces designated as “effective quiet” areas on a U.S. Navy aircraft carrier. Noise dosimetry samples were collected in 15 designated spaces, representing 15 noise measurements, while at-sea during airwing carrier qualifications. Equivalent sound level (Leq) measurements were collected during flight operations (Leq (flt ops)), non-flight operations (Leq (non-flt ops)), and over 24-hr periods (Leq (24-hr)). These data were compared to the 70 dBA American Conference of Governmental Industrial Hygienists (ACGIH®) Threshold Limit Value (TLV®) for “effective quiet” areas intended for temporary threshold shift recovery when personnel live and work in a potentially noise hazardous environment for periods greater than 24?hr. The monitored areas were selected based on personnel occupancy/use during off-duty time periods. Areas were classified by either (1) leisure areas that included mess (eating areas), gyms, lounges, an internet cafe, and the fantail social area or (2) berthing (sleeping) areas. The Leq measurements in decibels “A” weighted (dBA) were compared to determine significant differences between Leq (flt ops), Leq (non-flt ops), and Leq (24-hr) and were compared between leisure area and berthing area. Measured noise levels according to time period ranged as follows: (1) Leq (24-hr): 70.8–105.4 dBA; (2) Leq (flt ops): 70–101.2 dBA; and (3) Leq (non-flt ops): 39.4–104.6 dBA. All area measurements over the 24-hr period and during flight operations and 46.7% of the areas during the non-flight operation time period exceeded the “effective quiet” 70 dBA ACGIH TLV. Mean Leqs were 15 dBA higher during flight operations compared to non-flight operations in “effective quiet” areas (p?=?0.001). The Leqs in leisure areas were significantly higher than berthing areas by approximately 21 dBA during non-flight operation periods (p?=?0.001). Results suggest noise levels in “effective quiet” areas frequented by aircraft carrier personnel during off-duty hours when at-sea may inhibit auditory recovery from occupational noise exposures that occur on-duty. 相似文献
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Heat stress (HS) is a notable risk factor for female reproductive performance. In particular, impaired oocyte maturation was thought to contribute largely to the HS-induced reproductive dysfunctions. In this study, we confirmed that oocytes undergoing GVBD were much susceptible to HS, and thus compromising subsequent embryonic development. Using N-acetyl-l-cysteine (NAC), we found supplementation of a relatively high dose NAC during in vitro maturation, can protect oocytes from HS-induced complications, and thus rescuing impaired embryonic development. Further analysis indicated that mechanisms responsible for protecting GVBD oocytes from HS by NAC may include: (1) reversing disorganized spindle assembly and inhibited extracellular signal–regulated kinase (ERK) signaling; (2) correcting erroneous H3K27me3 modification and dysregulated expression of imprinted genes; (3) alleviating increased intraoocyte reactive oxygen species accumulation and apoptosis initiation. Our study, focusing on the oocyte meiotic maturation, may provide a safe and promising strategy for protecting reproductive sows under environmental hyperthermal conditions. 相似文献
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Maaike van Gerwen MD Naomi Alpert MS Raja Flores MD Emanuela Taioli MD PhD 《American journal of industrial medicine》2020,63(2):115-120
The association between asbestos exposure, mainly in occupational settings, and malignant mesothelioma has been well established; this has prompted several countries to establish mesothelioma epidemiologic surveillance programs often at the request of national agencies. This review compares currently existing mesothelioma registries worldwide to develop a concept model for a US real-time case capture mesothelioma registry. Five countries were identified with a mesothelioma specific registry, including Italy, France, UK, Australia, and South Korea. All, except the UK, used interviews to collect exposure data. Linkage with the national death index was available or was in future plans for all registries. The registries have limited information on treatment, quality of life, and other patient-centered outcomes such as symptoms and pain management. To thoroughly collect exposure data, “real-time” enrollment is preferable; to maximize the capture of mesothelioma cases, optimal coverage, and a simplified consent process are needed. 相似文献
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BackgroundPrior reports demonstrate the expression of estrogen and progesterone receptors in high-grade gliomas (HGGs), but the relationship between hormone receptor-positive disease and risk of HHGs in patients with breast cancer (BC) remains uncharacterized.MethodsUsing the SEER 18 registries (2000–2017), we examined the temporal trend of the incidence of HGGs and BC. The standardized incidence ratio was calculated to assess the risk of subsequent HGG in BC patients.ResultsDuring the study period, the incidence of BC and HGGs remained comparable for men and women. Among 976,134 patients with BC, we found a decreased incidence of HGGs in females, but not in males. Female BC patients with hormone receptor-positive disease were at a lower risk of developing glioblastoma and anaplastic astrocytoma.ConclusionOur study findings allude to the protective role of hormone exposure in the development of HGGs, which may lead to the development of therapies targeting hormonal pathways. 相似文献
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《Gastroenterologia y hepatologia》2019,42(10):604-613
IntroductionSunlight exposure is the main source of vitamin D. Our aim was to describe both sun exposure and sun protection behaviour in a series of patients with inflammatory bowel disease (IBD), and to study their potential association with vitamin D concentration.Patients and methodsA cross sectional, observational study. The clinical-demographic variables were obtained via clinical interviews and medical history review. The sunlight exposure assessment was carried out using the Sun Exposure Questionnaire and the concentration of 25-hydroxy vitamin D (25OHD) was measured by an electro-chemiluminescence immunoassay. Questionnaires were conducted on quality of life, physical activity, weekly vitamin D intake and sun protection behaviour.Results149 patients were included. In 69% of patients, deficient or insufficient 25OHD values were recorded. 67% showed low sun exposure. A modest significant correlation was observed between the total score of the solar exposure questionnaire and the 25OHD concentration in the complete series (r = 0.226, P = .006) and in the summer (r = 0.274, P = .01). The sun protection behaviour questionnaire score did not influence the 25OHD concentration. In the multivariate analysis, only the presence of clinical activity was associated with low sun exposure (OR = 3.23).DiscussionSun exposure according to the questionnaire used was low, was associated with the presence of clinical activity and was weakly correlated with serum 25OHD concentration. More studies are needed to explore the use of individual questionnaires for sun exposure and its relationship with vitamin D in patients with IBD. 相似文献
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The presence of pesticides in the Israeli food supply is well documented but little is known about the risks posed by children's diets for potential exposures. We investigated potential exposures to food-borne pesticides in a sample of 301 urban Israeli children (2008–10). Data from a food frequency questionnaire, 24 hour food recall, and Israel's national pesticide monitoring program were used to estimate uptake factors for 26 compounds in 27 fruits and vegetables. A pilot risk assessment was performed and the findings were compared with the Israel Ministry of Health's 2012 pesticide risk assessment for the general population. The surveyed children had higher potential exposures than the general population for over one third of the compounds, and uptake factors exceeded the Acceptable Daily Intake in ten compounds. Methamidophos, exceeded the ADI at the 25th percentile and fenamiphos, iprodione, and oxydemethon methyl, exceeded the ADI at the 50 percentile. ADIs for several compounds were exceeded even though the residues detected were below the statutory limit. Improved monitoring, enforcement, and revision of the Maximum Residue Limit for certain food/pesticide pairs are indicated as is the need to incorporate data on children's actual food consumption in national risk assessments. 相似文献