The potential adult adverse health outcomes that result from exposures during early life are recognized. However, only limited attention has been paid to the effect(s) of environmentally relevant toxicant exposures during critical periods of development and even fewer studies have examined whether early life inhalation exposures leads to adult disease. Our research is investigating whether inhalation exposures to real world dust during development can lead to changes in lung function and structure in adults. If so, what are the critical times of exposure that lead to those changes? Using metal-containing real world dusts collected from an abandoned mine tailings site, we have exposed male and female mice only in utero, only post-natally or continuously (in utero and postnatal inhalation exposures). We have found that significant changes in lung function and structure are only seen in adult male mice following continuous exposures. In addition, alterations in protein expression of airway cells ...
The behavioral effects induced by methyl-n-amyl ketone (110430) (MAK) exposure were studied. Rats received from one to eight intraperitoneal injections (group I) of 18, 37, 74, or 175 milligrams per kilogram (mg/kg) MAK, or were exposed to MAK aerosols (Group II) of 800 to 1,900 parts per million (ppm) daily for 6 or 8 hours. Following inhalation exposures, the rats were given injections of 37, 74
TY - CONF. T1 - Gas phase synthesis of TiO2-nanoparticles for inhalation exposure studies. AU - Miettinen, Mirella. AU - Tapper, Unto. AU - Backman, Ulrika. AU - Joutsensaari, Jorma. AU - Auvinen, Ari. AU - Jokiniemi, Jorma. PY - 2008. Y1 - 2008. M3 - Conference article. T2 - European Aerosol Conference 2008, EAC 2008. Y2 - 25 August 2008 through 29 August 2008. ER - ...
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Adverse health effects by inhaled and deposited particles are of great concern. In addition, therapeutic aerosols become increasingly important for the treatment of lung and other diseases. The interaction of particles with the inner surface of the lungs is fundamental for their biological effectiveness in the organism, though poorly understood and precluded from being studied in humans. A large number of animals are used to test the effects of aerosol particles on a living system by whole-body or nose-only exposures. Such experiments are time consuming and they are stressful for the animals. Furthermore, the increase of knowledge in the use of animal models is hampered for various reasons, such as the long time lapse between aerosol application and lung fixation, the lack of methods for direct studies, or artefacts produced by chemical lung fixation. Cell cultures which are in common use today are deficient in important structural components of the inner lung surface, such as macrophages, ...
The general population is exposed to CDFs by inhalation, ingestion of drinking water, consumption of food, and through the use of certain consumer products. Since the concentrations of CDFs in ambient air and drinking water are low (see Section 5.4), the intake of CDFs by inhalation and ingestion of drinking water would be low. It has been shown that inhalation exposure was not a major pathway of human exposure to CDFs (Travis and Hattermer-Frey 1989). The estimate that inhalation exposure.... ...
In case of a radioactive release, it is important to have good preparedness with the right actions to contribute the best protection for the vulnerable section of the population. Immediately after a release theexposure through inhalation will be the biggest problem, since particles and gases have not beendeposited on land, clouds and so on. Buildings contribute to protection against inhalation. The reason forthis is that the air outside and inside the dwelling is changed relatively slowly. How much of the pollutionthat enter the indoor air and how long time it takes is important information to determine if thepopulation is sufficiently protected inside buildings or if evacuation is needed. In this work knowledgefrom existing literature and modelling has been used to describe general conditions with which apollutant moves in and out of a building. Differential equations with main processes and parameters havebeen studied to give a estimation as to the protection a building can provide against ...
Felix, Human infection with hanta-virus occurs through inhalation of infected material, so as long as you werent breathing, or picking your nose when you were around the moose droopings, youll be OK, other-wise, head for the nearest epidemiologist. ,Al ...
... RIFM Innovative Model Calculates Inhalation Exposure To Fragrance Materials [03-May-2012] - RIFM 2-Box Indoor Air Dispersion Model Is An Alternative Method To Calculate Inhalation Exposure To Fragrance WOODCLIFF LAKE, New Jersey, May 3, 2012 /PRNewswire/ --The Research Institute for Fragrance Materials, Inc. (RIFM) is beta testing its innovative 2-Box Indoor Air Dispersion Model software, an alternative method for assessing inhalation exposure to fragrance materials. RIFM Database subscribers can download the model for individual use by selecting Tools and Models from the RIFM Database home page and then selecting the model for download.
Double-blind, sham- and placebo-controlled randomized study of effects of freshly-generated diluted diesel exhaust inhalation on vascular function. To examine role of adrenergic system a trial of alpha-blocker terazosin is also used. Each participant completes four study sessions, separated by at least three weeks: 1) Diesel exhaust inhalation (DE, controlled at 300 micrograms/cubic meter for two hours) and terazosin (2 mg prior to inhalation exposure); 2) DE plus placebo (matched for terazosin); 3) filtered air plus terazosin; and 4) filter air plus placebo. The investigators assess outcomes of blood pressure, forearm brachial artery ultrasound, and plasma measures of endothelial activation. The investigators hypothesize that DE exposure will be associated with increased blood pressure, decreased brachial artery diameter, and increased circulating endothelins, and that these effects will be attenuated by terazosin administration ...
Double-blind, sham- and placebo-controlled randomized study of effects of freshly-generated diluted diesel exhaust inhalation on vascular function. To examine role of adrenergic system a trial of alpha-blocker terazosin is also used. Each participant completes four study sessions, separated by at least three weeks: 1) Diesel exhaust inhalation (DE, controlled at 300 micrograms/cubic meter for two hours) and terazosin (2 mg prior to inhalation exposure); 2) DE plus placebo (matched for terazosin); 3) filtered air plus terazosin; and 4) filter air plus placebo. The investigators assess outcomes of blood pressure, forearm brachial artery ultrasound, and plasma measures of endothelial activation. The investigators hypothesize that DE exposure will be associated with increased blood pressure, decreased brachial artery diameter, and increased circulating endothelins, and that these effects will be attenuated by terazosin administration ...
Environ Health Perspect: 11/22/13. Background: Diesel engine exhaust (DEE) has recently been classified as a known human carcinogen.. Objective: To derive a meta-exposure-response curve (ERC) for DEE and lung cancer mortality and estimate lifetime excess risks (ELRs) of lung cancer mortality based on assumed occupational and environmental exposure scenarios.. Methods: We conducted a meta-regression of lung cancer mortality and cumulative exposure to elemental carbon (EC), a proxy measure of DEE, based on relative risk (RR) estimates reported by three large occupational cohort studies (including two studies of workers in the trucking industry and one study of miners). Based on the derived risk function, we calculated ELRs for several lifetime occupational and environmental exposure scenarios, and also calculated the fractions of annual lung cancer deaths attributable to DEE. Read more. ...
Background: Epidemiological evidence demonstrates that exposure to traffic-derived pollution worsens respiratory symptoms in asthmatics, but controlled human exposure studies have failed to provide a mechanism for this effect. Here we investigated whether diesel exhaust (DE) would induce apoptosis or proliferation in the bronchial epithelium in vivo and thus contribute to respiratory symptoms.. Methods: Moderate (n = 16) and mild (n = 16) asthmatics, atopic non-asthmatic controls (rhinitics) (n = 13) and healthy controls (n = 21) were exposed to filtered air or DE (100 μg/m 3 ) for 2 h, on two separate occasions. Bronchial biopsies were taken 18 h post-exposure and immunohistochemically analysed for pro-apoptotic and anti-apoptotic proteins (Bad, Bak, p85 PARP, Fas, Bcl-2) and a marker of proliferation (Ki67). Positive staining was assessed within the epithelium using computerized image analysis.. Results: No evidence of epithelial apoptosis or proliferation was observed in healthy, allergic or ...
The Organisation for Economic Cooperation and Development (OECD) announced the release of 17 new, updated, corrected or deleted Test Guidelines. The Test Guidelines include three that are specifically developed for nanomaterials.. A full list of publications in the Series on the Safety of Manufactured Nanomaterials is available on the OECD WPMN website via http://www.oecd.org/env/ehs/nanosafety/publications-series-safety-manufactured-nanomaterials.htm. (1) Test No. 318: Dispersion Stability of Nanomaterials in Simulated Environmental Media (PDF, 1.5 MB). This document offers guidelines on a test procedure to gain information on dispersion stability of manufactured nanomaterials in simulated environmental media. It allows the users to understand the nanomaterials fate in natural waters and their potential behaviour in test media.. (2) Test No. 412: 28 days (Subacute) Inhalation Toxicity Study (PDF, 354 KB). (3) Test No. 413: Subchronic Inhalation Toxicity: 90-day Study (PDF, 354 KB). Both ...
Video articles in JoVE about inhalation exposure include Whole-Body Nanoparticle Aerosol Inhalation Exposures, Dry Powder and Nebulized Aerosol Inhalation of Pharmaceuticals Delivered to Mice Using a Nose-only Exposure System, A Robust Pneumonia Model in Immunocompetent Rodents to Evaluate Antibacterial Efficacy against S. pneumoniae, H. influenzae, K. pneumoniae, P. aeruginosa or A. baumannii, Identification of Metal Oxide Nanoparticles in Histological Samples by Enhanced Darkfield Microscopy and Hyperspectral Mapping, The Lambda Select cII Mutation Detection System, An Experimental Model to Study Tuberculosis-Malaria Coinfection upon Natural Transmission of Mycobacterium tuberculosis and Plasmodium berghei, Non-surgical Intratracheal Instillation of Mice with Analysis of Lungs and Lung Draining Lymph Nodes by Flow Cytometry, Direct Tracheal Instillation of Solutes into Mouse Lung, Capsular Serotyping of Streptococcus pneumoniae by Latex Agglutination.
A colorless gas with a sharp, pungent odor. Fumes strongly in moist air. Nonflammable. Corrosive to metals and tissues and irritating to the eyes and respiratory system. Heavier than air. Long-term inhalation of low concentrations or short-term inhalation of high concentrations has adverse health effects. Prolonged exposure to fire or intense heat may result in the violent rupture and rocketing of the container. Used in the manufacture of rubber, pharmaceuticals, chemicals, and in gasoline refining and metals processing.. Rate of onset: Immediate. Persistence: Minutes to hours. Odor threshold: 0.77 ppm. Source/use/other hazard: Ore, other metal refining/cleaning; food/pickling; petroleum; corrosive liq.. ...
The information was provided to the workers from the year of introduction of diesel equipment at each facility , a surrogate for diesel exhaust exposure, from a variety of sources, including a 1998-2001 survey of diesel exhaust exposure at each facility, data from the U.S. Mine Safety and Health Administration Mine Information data Analysis system compliance database, data on diesel equipment usage over time and historical data at each facility mine ventilation... Its really no secret to deal with the sleep deprivation with a new baby with a new baby after Reynolds practicing Nurture try a healthy diet, and not on any additional take on tasks outside the home - you won t have time for them and nap when stay stay. Calm with a dramatic change in the life and routine, it can be difficult to stay cool and collected, but thats the key your baby your baby on an even keel. Even if something is wrong, reflects your mood and response to[ their] disposition. Are are freaking out, they do not ...
The breathing system comprises a canister carrying layered filtering material, including activated carbon granules, a dessicant, a catalyst for the catalyzation of carbon monoxide to carbon dioxide, optionally lithium peroxide, for conversion of CO2 to O2, and electrostatically charged filters between the layers of filtering material. A mouthpiece carrying a noseclip, and inhalation and exhalation check valves and a whistle is disposed within a flexible, substantially completely transparent hear-through hood, both the mouthpiece and hood being disposed in the canister between the filtering material and a cover for the canister. In use, the cover is removed, air inlet apertures are uncovered, and the hood is drawn about an individuals head and substantially sealed about the neck. With the mouthpiece in the individuals mouth, and noseclip closing off the users nose, inhalation causes air to flow through the filtering material and the inhalation check valve and past the exhalation check valves. When
1. Locate a current SDS for one of the fixatives described in todays lab. Identify the properties and hazards associated with that chemical. Methanol that is used in Precipitation fixation Dangerous Good Class: 3 (Flammable liquid) Subsidiary Risk(s): 6.1 (Toxic) Risk: - Highly flammable. - Toxic by inhalation, in contact with skin and if swallowed. - Toxic: danger of very serious irreversible effects through inhalation, in contact with skin and if swallowed. Safety Phrases: - Keep container tightly closed. - Keep away from sources of ignition - No smoking. - Avoid contact with skin. - Wear suitable protective clothing and gloves. - In case of accident or if you feel unwell seek medical advice immediately (show the label where possible). ...
1. The activities or operations where the workers are exposed to the chemical agents shall be considered unhealthy when the tolerance limits in Table 1 of this Annex are exceeded.. 2. All values given in Table 1 (Table of Tolerance Limits) are only for the absorption through inhalation.. 3. All values given in Table 1 as "simple asphyxiant" determine that, in the presence of these substances in the work environment, the minimum concentration of oxygen must be 18% by volume. The activities and operations in which the oxygen concentration is below, this value shall be considered as an imminent and serious risk.. 4. The chemical agents whose tolerance limits cannot be exceeded at any time during the working day are marked in the "Ceiling Limit" column.. 5. The chemical agents that can be absorbed through the skin and therefore requiring the use of gloves while handling, in addition to necessary PPE for protection of other body parts, are shown in the "Absorption through skin" column.. 6. The ...
Darkened lips can result from months and years of smoking. Nicotine and tar transfer to the lips through inhalation of the cigarette smoke, causing...
سلامت کار ایران Iran Occupational Health (IOH) seeks to publish Original Research Papers and Case Reports, Review Articles and Technical Reports related to the fields of Public Health and Occupational Health particularly. IOH is an official publication of Iran University of Medical Sciences, Faculty of Public Health and is published quarterly. The following guidelines refer to the Journal requirements for receiving your manuscripts for possible publication. Complying with guidelines will expedite the process of evaluation and publication of the submitted manuscripts. IOH regrets to reject those contributions that deviate from the Journal style.
Question by Amit Varma. In the book "The World of _____" by Bennett Alan Weinberg and Bonnie K Bealer, there is a photograph of a label from a jar of pharmaceutical-grade crystals. It reads:. "WARNING: MAY BE HARMFUL IF INHALED OR SWALLOWED. HAS CAUSED MUTAGENIC AND REPRODUCTIVE EFFECTS IN LABORATORY ANIMALS. INHALATION CAUSES RAPID HEART RATE, EXCITEMENT, DIZZINESS, PAIN, COLLAPSE, HYPOTENSION, FEVER, SHORTNESS OF BREATH. MAY CAUSE HEADACHE, INSOMNIA, VOMITING, STOMACH PAIN, COLLAPSE AND CONVULSIONS.". Fill in the blank.. ...
A new long-term study by the National Cancer Institute and the National Institute for Occupational Safety and Health found that miners exposed to diesel engine exhaust are three times more likely to contract fatal lung cancer, and that commuters on busy highways in smoggy, urban areas might face a similar risk ...
Brands: STELLAR Telemetry sets new standards in wireless animal physiology monitoring where the animal can move anytime, anywhere and still record your data gap-free and loss-less using the latest technology. TSE DACO is a comprehensive software solution for inhalation exposure studies. The Daco software package allows unparalleled flexibility in experimental design and data recording. The flexibility is reflected in the control of the experimental setup, allowing a mix of different exposure systems, all the way through the analysis parameters and even offers an advanced software version with implementation of specific GLP checkpoints and audit trails termed Daco-GLP.. ...
Researchers are now adding additional data to the obesity puzzle, citing that diesel exhaust exposure while in utero could also be to blame for the rise in
HSE has highlighted the importance of managing health risks effectively after a Gateshead company admitted exposing its workers to hazardous soldering fumes. View press release
Human, Manganese, Rat, Rats, Cells, Cell, Concentrations, Tissue, Tissues, Adult, Sexual Development, Testes, Inhalation, Fetus, Testosterone, Risks, Brain, Diet, Inhalation Exposures, Liver
This presentation will address some of the obstacles with studies in juvenile animals related to specialty endpoints or routes of delivery as well as approaches to overcome them. Discussion topics include cardiovascular assessment, immunophenotyping, and T-cell dependent antibody response (TDAR) evaluation in juvenile dogs, and approaches to inhalation exposure of neonatal/juvenile rodents, and dogs.. ...
Find patient medical information for Asmanex Twisthaler Inhalation on WebMD including its uses, side effects and safety, interactions, pictures, warnings and user ratings.
Many studies have been carried out, using several animal species, to evaluate the potential carcinogenicity of exposure to whole exhaust and to components of exhaust from diesel- and gasoline-fuelled internal combustion engines. The studies are considered within six subgroupings: (i) whole diesel engine exhaust; (ii) gas-phase diesel engine exhaust (with particles removed); (iii) diesel engine exhaust particles or extracts of diesel engine exhaust particles; (iv) whole gasoline engine exhaust; (v) condensates/extracts of gasoline engine exhaust; and (vi) engine exhausts in combination with known carcinogens. Whole diesel engine exhaust Mice, rats, Syrian hamsters and monkeys (Macaca fascicularis) were exposed by inhalation to a range of concentrations of whole diesel engine exhaust, with observations in some studies extending to the lifespan of the animals. Five studies conducted using two different strains of rats showed an increased incidence of benign and malignant lung tumours that was ...
TY - JOUR. T1 - Autoradiographic analyses of Guinea pig airway tissues following inhalation exposure to C-labeled methyl isocyanate. AU - Kennedy, Amy L.. AU - Singh, Gurmukh. AU - Alarie, Yves. AU - Brown, William E.. PY - 1993/1/1. Y1 - 1993/1/1. N2 - Through the use of radioactively labeled methyl isocyanate (MIC), the deposition, penetration, and clearance of this highly reactive compound in the airway at the tissue and cellular levels have been directly examined. Guinea pigs were exposed to 14C-MIC vapors at concentrations ranging from 0.38 to 15.2 ppm for periods of 1-6 hr. Solubilization of tissues from these animals showed the airway tissues to have the highest level of radioactivity. In the nasal region, 14C deposition, as monitored by histoautoradiography, was limited to the epithelial layer, was related to dose, and was dependent on the specific epithelial cell type. The squamous epithelium was minimally labeled on the surface and the label did not penetrate the cell layer. However, ...
TY - JOUR. T1 - Occupational exposure to diesel engine exhaust and alterations in lymphocyte subsets. AU - Lan, Qing. AU - Vermeulen, Roel. AU - Dai, Yufei. AU - Ren, Dianzhi. AU - Hu, Wei. AU - Duan, Huawei. AU - Niu, Yong. AU - Xu, Jun. AU - Fu, Wei. AU - Meliefste, Kees. AU - Zhou, Baosen. AU - Yang, Jufang. AU - Ye, Meng. AU - Jia, Xiaowei. AU - Meng, Tao. AU - Bin, Ping. AU - Kim, Christopher. AU - Bassig, Bryan A.. AU - Hosgood, H. Dean. AU - Silverman, Debra. AU - Zheng, Yuxin. AU - Rothman, Nathaniel. PY - 2015/5/1. Y1 - 2015/5/1. N2 - Background: The International Agency for Research on Cancer recently classified diesel engine exhaust (DEE) as a Group I carcinogen based largely on its association with lung cancer. However, the exposure-response relationship is still a subject of debate and the underlying mechanism by which DEE causes lung cancer in humans is not well understood. Methods: We conducted a cross-sectional molecular epidemiology study in a diesel engine truck testing ...
A Working Group of the International Agency for Research on Cancer (IARC) convened in Lyon, France, June 5-12 to scrutinise the available knowledge base on the carcinogenicity of diesel engine exhaust, gasoline engine exhaust and some nitroarenes.1 Diesel and gasoline engine exhaust and nitroarenes were previously evaluated by IARC in 1989.2 For gasoline engine exhaust the classification remained Group 2B (possibly carcinogenic to humans) as well as for seven of the nitroarenes. The newly evaluated nitroarene 3-nitrobenzanthrone was also added to this group. 6-Nitrochrysene and 1-nitropyrene were classified as 2A Probably carcinogenic to humans. 6-Nitrochrysene and 1-nitropyrene are important exposure markers for diesel exhaust since metabolites of these substances have been found in workers exposed to diesel exhaust.3-5 The most prominent outcome of the IARC evaluation meeting was the upgrade of the classification of diesel exhaust, now in Group 1 Carcinogenic to humans with sufficient ...
Inhalation of hexavalent chromium [Cr(VI)] is associated with increased lung cancer risk among workers in several industries, most notably chromate production workers exposed to high concentrations of Cr(VI) (≥100 μg/m(3)), for which clear exposure-response relationships and respiratory irritation and tissue damage have been reported. Data from this industry are used to assess lung cancerrisk associated with environmental and current occupational exposures, occurring at concentrations that are significantly lower. There is considerable uncertainty in the low dose extrapolation of historical occupational epidemiology data to assess risk at current exposures because no published or well recognized mode of action (MOA) for Cr(VI)-induced lung tumors exists. We conducted a MOA analysis for Cr(VI)-induced lung cancer evaluating toxicokinetic and toxicological data in humans and rodents and mechanistic data to assess plausibility, dose-response, and temporal concordance for potential MOAs. ...
2-Chloronitrobenzene and 4-chloronitrobenzene are oily yellow solids that are used primarily as chemical intermediates in the production of dyes, lumber preservatives, drugs, and photographic chemicals. Although these chemicals are solids at room temperature, the vapor pressures of these chemicals are sufficiently high to result in significant inhalation exposure. Toxicity studies of 2-chloronitrobenzene and 4-chloronitrobenzene were performed by exposing male and female F344/N rats and B6C3F1 mice to the chemicals by whole-body inhalation 6 hours per day, 5 days per week, for 2 weeks or 13 weeks. Animals were evaluated for histopathology, clinical chemistry (rats), hematology (rats), and reproductive system effects. In separate studies, the dermal absorption ofthe chemicals was compared, and the absorption, distribution, metabolism, and excretion were partially characterized following oral administration to male F344/N rats. 2-Chloronitrobenzene and 4-chloronitrobenzene were also administered ...
A new report published by the National Academies Press (NAP) focuses on EPAs controlled human inhalation exposure (CHIE) studies, which are also referred to as human clinical studies or human challenge studies. These studies involve individuals who volunteer to be exposed to air pollutants intentionally in controlled laboratory settings. According to the report, CHIE studies allow measurements to be made of "biomarker or physiologic responses to those exposures that can indicate pathways of toxicity and mechanisms of air-pollution responses." The results of this research are used to help inform policy decisions and establish or revise standards intended to protect public health and improve air quality. The report provides guidance on the conduct of CHIE studies, assesses the utility of these studies to inform and reduce uncertainties in setting air-pollution standards, assesses whether the continuation of CHIE studies is warranted, and evaluates the potential health risks to test subjects who ...
A blood agent is a toxic chemical agent that affects the body by being absorbed into the blood. Blood agents are fast-acting, potentially lethal poisons that typically manifest at room temperature as volatile colorless gases with a faint odor. They are either cyanide- or arsenic-based. Blood agents work through inhalation or ingestion. As chemical weapons, blood agents are typically disseminated as aerosols and take effect through inhalation. Due to their volatility, they are more toxic in confined areas than in open areas. Cyanide compounds occur in small amounts in the natural environment and in cigarette smoke. They are also used in several industrial processes and as pesticides. Cyanides are released when synthetic fabrics or polyurethane burn, and may thus contribute to fire-related deaths. Arsine gas, formed when arsenic encounters an acid, is used as a pesticide and in the semiconductor industry; most exposures to it occur accidentally in the workplace. The symptoms of blood agent ...
Acrylonitrile is a monomer used extensively as a raw material in the manufacturing of acrylic fibers, plastics, synthetic rubbers, and acrylamide. It has been classified as a probable human carcinogen according to the results of numerous chronic rat bioassays. The present report summarizes the toxicity data on acrylonitrile and reviews available data concerning the mechanism (genetic versus epigenetic) by which acrylonitrile is carcinogenic in rats. From the evaluation of the relevant toxicity data, it can be concluded that acrylonitrile is indeed carcinogenic to rats after either oral or inhalational exposure. However, information on other mammalian species is lacking, and, moreover, the exact mechanism of the carcinogenic process is unclear. Therefore, it is recommended to conduct an additional long-term inhalation carcinogenicity study with acrylonitrile in mice, as well as studies into the mechanism by which acrylonitrile induces (brain) tumors in rats (genetic versus epigenetic).. ...
There are consistent temporal associations between exposure to air pollutants and HF hospitalizations and mortality (10,11). To our knowledge, this trial is the first randomized study to show that a simple filter intervention could reduce endothelial dysfunction and BNP increases associated with short-term exposure to DE in patients with HF. Our findings suggest that PM2.5 is the most important cause of endothelial dysfunction associated with air pollution exposure. Surprisingly, we also found a reduction in arterial stiffness during DE, which was unaffected by the filter.. Our findings on endothelial dysfunction during DE are consistent with experimental HF mouse models (26) and similar to reports in healthy volunteers (27,28) and patients with diabetes (29). Two pathways have been proposed to explain these effects: first, a pulmonary acute phase response could release inflammatory mediators into the circulation and be a causal link between particle inhalation and cardiovascular disease (30); ...
Hypersensitivity pneumonitis (HP), also referred to as extrinsic allergic alveolitis, is a pulmonary disease that occurs due to inhalational exposure to a variety of antigens leading to an inflammatory response of the alveoli and small airways. Systemic manifestations such as fever and fatigue can accompany respiratory symptoms. Although sensitization to an inhaled antigen as manifested by specific circulating IgG antibodies is necessary for the development of HP, sensitization alone is not sufficient as a defining characteristic, because many sensitized individuals do not develop HP. The incidence and prevalence of HP are variable, depending on geography, occupation, avocation, and environment of the cohort being studied. As yet unexplained is the decreased risk of developing HP in smokers. ...
Maintenance of lipid metabolism is crucial for cellular function in all tissues, and perturbations in lipid homeostasis occur in a range of human diseases. Pulmonary surfactant, which maintains alveolar surface tension, is approximately 90% lipid (18). There is a growing body of evidence indicating that pulmonary surfactant and associated lipid metabolism has broader roles in maintenance of pulmonary immune homeostasis and host defense. Thus, any exposure that interferes with these critical processes may be expected to have profound effects on the lung microenvironment.. In this issue, Madison et al. employed a mouse model of chronic inhalational exposure to study the in vivo effects of ENDS-associated vehicle solvents PG and VG in comparison to conventional tobacco smoke exposure (19). In contrast with tobacco smoke, the authors observed no emphysematous changes nor increased airway inflammation following 4 months of exposure to ENDS (with or without nicotine). Despite not showing any ...
Looking for a great looking Football Resuable Fabric Masks? Then look no further. This masks work for any and all occasions. * Washable * Re-Usable * One size fits all * Raw edges * Two ear holes accommodate diverse face shapes and sizes * Contoured design to cover the wearers nose and mouth * Moisture wicking fabric * 100% Poly filament *Disclaimer: The face cover should not be used (1) in any surgical setting or where significant exposure to liquid, bodily or other hazardous fluids, may be expected; (2) in a clinical setting where the infection risk level through inhalation exposure is high; or (3) in the presence of a high-intensity heat source or flammable gas*
ABSTRACT Particle deposition on indoor surfaces has lately received great attention due to increasing concern about the effects of particle exposure on human health. In this study, we developed an easy and low-cost method of measuring the deposition amounts of different-sized particles and evaluated it through particle concentration measurement and theory calculation. First, a clean charge-coupled device (CCD) chip was exposed to air in order to receive the deposition of airborne particles. After sedimentation, images generated by the CCD of the deposited particles were analyzed, and the quantity of particles in each size range (> 2 µm) was identified based on the unique pixel sizes. Using a particle counter and a dust monitor, we also measured the concentrations of airborne particles with different sizes near the chip during sedimentation and compared them with the numbers of settled particles. The results show that the particle deposition can be quantified with this method and that a positive
Healthcare personnel handling cytostatic antineoplastic agents may be exposed to these drugs. Exposure may occur through inhalation, skin contact, skin absorption, ingestion, or injection during preparation, administration, and disposal. Since the late 70s, occupational exposure to these drugs has been recognized as a potential health hazard.. Since then, several countries have published guidelines and recommendations with the objective to improve operating procedures and safety workplace, and keep exposure levels as low as possible. As a consequence, operating procedures have been improved,biological and environmental monitoring have been used to assess contamination and exposure levels, and a lot of analytical methods have been developed and validated.. In general, the strategy used to prevent or minimize occupational exposure applies a combination of interventions, such as engineering controls, administrative and work practice controls, and personal protective equipment.. In Italy, the ...
Results: The sampling and analytic methodology used in the study presents the potential to characterize nanoparticle exposure for a variety of operational processes. We found the highest mass exposure occurred at bagging job whereas the highest number and surface area concentration was found at modification. Modification is suspected to be the primary emission source. It is discovered nanoparticles in the size range of 20-300nm dominate in this workplace, which consists of 90-98% of particle counts in the respirable fraction. Based on the sampling results from 2012, there was a strong relationship between number concentration in 5-25um range and the respirable mass concentration (r= 0.908); however, no such correlation was found between number concentration in nanoscale and respirable mass (r= 0.018). The deposited surface area in TB (r=0.66) and alveolar region (r=0.46) was modestly correlated with number concentration of particles in the nanoscale ...
This study explores the relationship between inhalation amplitude and turn management in four approximately 20 minute long spontaneous multiparty conversations in Estonian. The main focus of interest is whether inhalation amplitude is greater before turn onset than in the following inhalations within the same speaking turn. The results show that inhalations directly before turn onset are greater in amplitude than those later in the turn. The difference seems to be realized by ending the inhalation at a greater lung volume value, whereas the initial lung volume before inhalation onset remains roughly the same across a single turn. The findings suggest that the increased inhalation amplitude could function as a cue for claiming the conversational floor.. ...
The biological effects of airborne particulate matter (PM) in humans stimulated many research activities in recent years. One type of particles …
Upon analysis, an inhalable elemental carbon mass concentration arithmetic mean of 10.6 μg/m3 (geometric mean 4.21 μg/m3) was found among workers exposed to MWCNT. The concentration equates to a deposited dose of approximately 4.07 μg/d in a human, equivalent to 2 ng/d in the mouse. For MWCNT inhalation, mice were exposed for 19 d with daily depositions of 1970 ng (equivalent to 1000 d of a human exposure; cumulative 76 yr), 197 ng (100 d; 7.6 yr), and 19.7 ng (10 d; 0.76 yr) and harvested at 0, 3, 28, and 84 d post-exposure to assess pulmonary toxicity. The high dose showed cytotoxicity and inflammation that persisted through 84 d after exposure. The middle dose had no polymorphonuclear cell influx with transient cytotoxicity. The low dose was associated with a low grade inflammatory response measured by changes in mRNA expression. Increased inflammatory proteins were present in the lavage fluid at the high and middle dose through 28 d post-exposure. Pathology, including epithelial ...
RUTGERS (US) - Delivering chemotherapy through inhalation significantly improves the rate of successfully treating cancer tumors in the lungs, new animal studies show.. Lung cancer kills about 1.5 million men and women around the world-more than the number of people who die from breast, colon, pancreatic, and prostate cancers combined.. Researchers say this happens, in part, because many patients with lung cancer are not diagnosed until they are in the advanced or metastatic stage of the disease and treatment options are limited mainly to surgery and conventional intravenous chemotherapy.. [sources]. The new research indicates that inhalation therapy reduces systemic damage done to healthy lung cells and other organs while improving the treatment of lung tumors.. "The development of additional more effective and safe approaches to treatment of this disease is vitally important," says Tamara Minko, professor and chair of the department of pharmaceutics at Rutgers.. "Up until now, limited clinical ...
By Xu, Cheng-Xiong Jere, Dhananjay; Jin, Hua; Chang, Seung-Hee; Chung, Youn-Sun; Shin, Ji-Young; Kim, Ji-Eun; Park, Sung-Jin; Lee, Yong- Hoon; Chae, Chan-Hee; Lee, Kee Ho; Beck, George R Jr; Cho, Chong- Su; Cho, Myung-Haing Rationale: The low efficiency of conventional therapies in achieving long-term survival of patients with lung cancer calls for the development of novel therapeutic options. Recent advances in aerosol-mediated gene delivery have provided the possibility of an alternative for the safe and effective treatment of lung cancer. Objectives: To demonstrate the feasibility and emphasize the importance of noninvasive aerosol delivery of Akt1 small interfering RNA (siRNA) as an effective and selective option for lung cancer treatment. Methods: Nanosized poly(ester amine) polymer was synthesized and used as a gene carrier. An aerosol of poly(ester amine)/Akt1 siRNA complex was delivered into K-ras^sup LA1^ and urethane-induced lung cancer models through a nose-only inhalation system. The ...
BACKGROUND: Vermeulen et al. 2014 published a meta-regression analysis of three relevant epidemiological US studies (Steenland et al. 1998, Garshick et al. 2012, Silverman et al. 2012) that estimated the association between occupational diesel engine exhaust (DEE) exposure and lung cancer mortality. The DEE exposure was measured as cumulative exposure to estimated respirable elemental carbon in μg/m(3)-years. Vermeulen et al. 2014 found a statistically significant dose-response association and described elevated lung cancer risks even at very low exposures. METHODS: We performed an extended re-analysis using different modelling approaches (fixed and random effects regression analyses, Greenland/Longnecker method) and explored the impact of varying input data (modified coefficients of Garshick et al. 2012, results from Crump et al. 2015 replacing Silverman et al. 2012, modified analysis of Moehner et al. 2013). RESULTS: We reproduced the individual and main meta-analytical results of Vermeulen ...
Histoplasmosis is caused by H.capsulatum, which is found in the stool of birds and bats and in soil contaminated by their stool, such as that near roosts, chicken coops, barns, caves, and underneath bridges. Transmission occurs through inhalation of H. capsulatumor H. capsulatum var.duboisii spores or through the invasion of spores after minor skin trauma.…. Details ...
Do you know essential oils can be used topically, through inhalation, cooking and even on pets? Explore the full uses of essential oils here!
Increased level of DNA damage, but not FPG sensitive sites, in lung cells by the alkaline comet assay in guinea pigs after intratracheal instillation of diesel engine exhaust particles. / Pedersen, L.M.; Møller, Per; Danesvar, B.; Wallin, H.; Autrup, H.; Loft, S.; Dragsted, L.O.. In: Neoplasma, Vol. 46, No. Suppl. S, 1999, p. 85-85.. Publication: Research - peer-review › Conference abstract in journal - Annual report year: 1999 ...
Article Use of an exposure chamber to maintain aqueous‐phase nanoparticle dispersions for improved toxicity testing in fish. A novel chamber for maintaining aqueous phase dispersions of nanoparticles (NPs) to enable improved toxicity testing in larva...
Lynch, D.W., Lewis, R.T., Moorman, W.J., Burge, J.R., Lal, J.B., Setzer, J.V., Groth, D.H., Gulati, D.K., Zavos, P.M., Sabharwal, P.S., Ackerman, L.J., Cockrell, B.Y., and Sprinz, H.: Effects on monkeys and rats of long-term inhalation exposure to ethylene oxide: Major findings of the NIOSH study. In: Hospital Ethylene Oxide Sterilization, Current Issues in EO Toxicity and Occupational Exposure. 8:7-10, 1984 ...
TSI aerosol monitors enable real-time, direct-reading aerosol monitoring & analysis. Call today for more information on our products!
TSI aerosol monitors enable real-time, direct-reading aerosol monitoring & analysis. Call today for more information on our products!
IITRI now has expanded animal biosafety level 3 (ABSL-3) capacity to conduct pathogen challenge studies for vaccines or therapeutics in non-human primates (NHPs). Our ABSL-3 laboratories include head-only aerosol infection by inhalation exposure and plethysmography capabilities for cynomolgus or rhesus monkeys, African green monkeys, and marmosets.
With only one high-performance industrial camera, the ANALYSETTE 28 ImageSizer covers an extremely wide measuring range and ensures thanks to its 5 megapixels, highest resolution of even smallest particles. Your advantage: In one image, large and small particles can be directly captured, displayed, edited and deleted. And a direct USB connection to the computer ensures the fastest possible data transmission for evaluation of the results. And the duration of the measurement can be varied depending on the desired number of images (up to 75 images/sec.) or on the number of measured particles. Highest shape precision due to telecentric lenses ...
Features: ValvTect Diesel Guard™ Supreme Plus High Performance Diesel Additive is specially formulated for heavy duty marine diesel engines
Objective: A DPI should be used with an IM that is as deep and as fast as possible from the start of inhalation (Laube BL et al Eur Respir J 2011;37:1308-1331). We have determined the effect of enhanced training using the In-Check Dial (IC) while subjects inhaled through a S and a T DPI.. Method: Child (CA: 6-17y) and adult (AA:18-45y) patients with asthma (mean FEV1 57 and 69% pred), COPD (52 % pred) and HA were randomised in an open-label design to receive IC with a S and a T. Two separate inhalations were measured using an inhalation profile recorder. The profile with the highest peak inhalation flow (PIF, L/min) was used for data analysis.. Results: Figures 1 and 2 show the % improvement in the maximum pressure change (MPC, kPa) and the acceleration of the flow (ACC, kPa/sec) inside each DPI during an inhalation after IC. ...
As local emissions regulations and programs continue to evolve to address the emissions of diesel powered construction equipment, more of the compliance burden is being placed on equipment owners.
Condition: New Size:. 89mm / 15P Drive: 1/2 DR Application: Isuzu, Mazda, Daihatsu Diesel Please Note: Vehicle model only for reference, Buyer sh
No part of this web site may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying or ...
EPL has expertise in the evaluation of respiratory tract tissues in animals exposed to chemicals and compounds via inhalation & other routes of exposure.
Discover an inhalation drug-delivery approach based on proven particle engineering through spray-drying technology and specialized encapsulation technology.
Webs largest site for Poisonous Materials Tagboard Placards. Buy Class 6 Inhalation Hazard Placard. Printed flexographically with light fast inks. Ships fast!
Detailed drug Information for Proventil Inhalation. Includes common brand names, drug descriptions, warnings, side effects and dosing information.
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The TD-300 device simplifies the dosing process for your patients, using a series of features designed to help with proper inhalation and administration of TYVASO®.
Inhalation humide Puressentiel respiratoire aide à humidifier et dégager le nez, respirer plus librement et facilite le bien-être respiratoire.
Define exhaust: to consume entirely : use up; to tire extremely or completely; to deprive of a valuable quality or constituent - exhaust in a sentence
PLEASE NOTE The word dust will frequently be used as a generic descriptor in lieu of aerosol or particulate mass. Dont be confused by this. References are provided on some of the slides. Complete reference articles are available upon request for most citations.
Are both DIESEL TEST 2010 and DIESEL TEST Hardcore both going to be regular products? Did I see somewhere a new version of DTH due out soon too? Any
Exhaust leak - I have a 92 Nissan King Cab 4 wheel drive four cylinder it has an exhaust leak I found out three bolts are sheared off can I just J-B ...
Luxusní oblečení Diesel. Originální, pohodlné a vždy stylové kousky z nových kolekcí známé módní značky Diesel za skvělé ceny!
Læderremmen er glat og brun, og urkassen er markant, spændende og sort på dette meget brede og høje supermoderne Deadeye herreur fra Diesel. Uret er vandtæt ne
TSI Incorporated DustTrak Aerosol Monitors. Advance aerosol monitoring from TSI Inc that simultaneously measures mass and size fraction.
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vanadium pentoxide v2o5 Manufacturers & vanadium pentoxide v2o5 Suppliers Directory - choose vanadium pentoxide v2o5 from 121 vanadium pentoxide v2o5 Super Suppliers of China.
Occupational exposure to nickel occurs mainly through inhalation of dust particles and fumes or through skin contact. Acute exposure to high levels of nickel by inhalation can cause severe damage to the lungs and kidneys. Prolonged exposure to nickel refinery dust among nickel refinery workers leads to an increased risk of lung and nasal cancers. Nickel refinery dust is a mixture including many nickel compounds as well as other inorganic substances. Nickel subsulfide is the major constituent in refinery dust from the smelting of sulfidic ores. Chronic dermal exposure to nickel can lead to dermatitis with complaints such as dry, irritated or itchy skin. Chronic inhalation exposure to metallic nickel and water-insoluble nickel compounds can result in respiratory effects, including decreased lung function and bronchitis. Chronic exposure to soluble nickel compounds by inhalation can also result in asthma cases.. Latency period between exposure and nickel related cancer varies from 13 to 24 ...
A mobile whole-body exposure system was developed for exposing mice to concentrated ambient particulate matter smaller than 2.5 microm in mass median aerodynamic diameter (MMAD). Each 20-L exposure cage was designed to hold 9 mice within individual compartments. This allowed for transport and subsequent exposure. Airflow mixing and the potential for stagnant areas within the compartments were modeled using computational fluid dynamic modeling (CFD). CFD analysis showed no stagnant areas and good mixing throughout the exposure cage. The actual performance of the exposure system was determined for 0.5 to 2.0 microm diameter aerosols by measuring (1) uniformity of aerosol distribution and (2) particle deposition in the tracheobronchial and pulmonary regions of mice exposed in the system. A 0.6-microm MMAD (GSD=2.0) cigarette smoke aerosol was used to experimentally measure the uniformity of aerosol distribution to the nine individual compartments. The average data from three runs showed no statistically
Few studies have explicitly explored the impacts of the extensive adjustment (with a lag period of more than one week) of temperature and humidity on the association between ambient fine particulate matter (PM2.5) and cardiovascular mortality. In a time stratified case-crossover study, we used a distributed lag nonlinear model to assess the impacts of extensive adjustments of temperature and humidity for longer lag periods (for 7, 14, 21, 28 and 40 days) on effects of PM2.5 on total cardiovascular mortality and mortality of cerebrovascular and ischemic heart disease and corresponding exposure-response relationships in Beijing, China, between 2008 and 2011. Compared with results only controlled for temperature and humidity for 2 days, the estimated effects of PM2.5 were smaller and magnitudes of exposure-response curves were decreased when longer lag periods of temperature and relative humidity were included for adjustments, but these changes varied across subpopulation, with marked decreases occurring
The pharmacokinetics of trichloroethylene (TCE) was characterized during and following inhalation exposures of male Sprague-Dawley rats. The blood and exhaled breath TCE time-course data were used to formulate and assess the accuracy of predictions of a physiologically based pharmacokinetic (PB-PK) model for TCE inhalation. Fifty or 500 ppm TCE was inhaled by unanesthetized rates of 325-375g for 2 hrs through a miniaturized one-way breathing valve. Repetitive samples of the inhaled and exhaled breath streams, as well as arterial blood, were collected concurrently during and for 3 hrs following the exposures and analyzed fo TCE by headspace gas chromatography. Respiratory rates and volumes were continuously monitored and used in conjunction with the pharmacokinetic data to delineate uptake and elimination profiles. Levels of TCE in the exhaled breath attained near steady-state soon after the beginning of exposures, and were then directly proportional to the inhaled concentration. Exhaled breath ...
A new IITRI poster presented at the recent ASM Biodefense and Emerging Diseases 2016 meeting is now available. In this poster, Winston Lin and colleagues describe the development of an aerosol model of infection for _B anthracis_ in rabbits using a modified 64-port inhalation nose-only exposure chamber with nebulizers. This platform produced consistent spray factors across concentrations. And, with capability for up to 8 rabbits, the platform potentially reduces variability in aerosol concentration delivery and minimizes the number of runs needed for a therapeutic or vaccine study.
Asbestos related disease, in particular affecting the lung, comprise of a broad spectrum of entities related to the inhalational exposure to asbestos fibers. They can be divided into benign and malignant changes 1-3. Benign pleural and parenchym...
If patients could recognise themselves, or anyone else could recognise a patient from your description, please obtain the patients written consent to publication and send them to the editorial office before submitting your response [Patient consent forms] ...
Epidemiological studies have demonstrated an association between different levels of air pollution and various health outcomes including mortality, exacerbation of asthma, chronic bronchitis, respiratory tract infections, ischaemic heart disease and stroke. Of the motor vehicle generated air pollutants, diesel exhaust particles account for a highly significant percentage of the particles emitted in many towns and cities. This review is therefore focused on the health effects of diesel exhaust, and especially the particular matter components. Acute effects of diesel exhaust exposure include irritation of the nose and eyes, lung function changes, respiratory changes, headache, fatigue and nausea. Chronic exposures are associated with cough, sputum production and lung function decrements. In addition to symptoms, exposure studies in healthy humans have documented a number of profound inflammatory changes in the airways, notably, before changes in pulmonary function can be detected. It is likely ...
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This paper presents the results of a study on the effect of using a continuously variable length intake runner (intake manifold) on Turbocharged multi-cylinder diesel engines. While there is a large amount of data available for naturally aspirated engines, no reliable source was found for the effect of varying the length of intake runner for Turbocharged engines. This study was done for relatively low-speed off-highway diesel engines.The study is based on the results of one-dimensional engine models simulated in AVL BOOSTTM engine simulation software. A simplified engine model has been used for the single cylinder naturally aspirated engine, to demonstrate the effects of varying intake runner effective length. The multi cylinder study is based on validated model of a 12 cylinder 1000hp turbocharged diesel engine. It has been found that multi-cylinder turbocharged diesel engines are more responsive to intake runner length variations than naturally aspirated engines ...
contact process. Vanadium pentoxide melts at 690 C and decomposes at 1750 C. V3+ is a strong reducing agent, which sets hydrogen free with water. This shows that Vanadium pentoxide may only rarely be applicable as sole oxidizing agent. Of interest are its abilities to form polyoxides. In the following process the oxidation number of the vanadium remains constant for example, but the polarization of the peroxide group increases:. ...
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A scanning mobility particle sizer (SMPS) is an analytical instrument that measures the size and number concentration of aerosol particles with diameters from 2.5 nm to 1000 nm. They employ a continuous, fast-scanning technique to provide high-resolution measurements. The particles that are investigated can be of biological or chemical nature. The instrument can be used for air quality measurement indoors, vehicle exhaust, research in bioaerosols, atmospheric studies, and toxicology testing. Lev Solomonovich Ruzer; Naomi H. Harley (2013). Aerosols Handbook: Measurement, Dosimetry, and Health Effects (Second ed.). CRC Press. pp. 234-. ISBN 978-1-4398-5519-5. Retrieved 28 April 2013. Burtscher, H. (2005). "Physical characterization of particulate emissions from diesel engines: a review". Journal of Aerosol Science. 36 (7): 896-932. doi:10.1016/j.jaerosci.2004.12.001. ISSN 0021-8502 ...
This topic contains 6 study abstracts on Diesel Exhaust Particle Toxicity indicating that the following substances may be helpful: Catechin, Rosemary, and Onion
Raghunathan: Exposure to airborne particulate matter has been linked to cardiovascular events. Whether this finding reflects an effect of particulate matter exposu...
In an effort to improve air quality and decrease dependence on petroleum, alternative fuels such as methanol have been considered to substitute for gasoline or diesel fuel. Methanol is also a candidate to provide the hydrogen for fuel cells. Before people are exposed to increased concentrations of methanol, the potential health effects of such exposures require study. Dr. Burbacher and colleagues of the University of Washington studied the effects of long-term exposure to methanol vapors on metabolism and reproduction in adult female monkeys (Macaca fascicularis) and developmental effects in their offspring, who were exposed prenatally to methanol.
Based on experimental studies results, the inhaled barium hexaferrite powder can be retained in the lungs for a long time period. Inside the lungs, the substance can cause adverse local effects as fiber deposition and subsequently pneumoconiosis. Therefore, a specific DNEL is established in order to characterize the risk for the long-term inhalation exposure. Experimental data show that inhaled barium hexaferrite powder may induce pneumoconiosis (identified as critical effect) following repeated exposure at concentration higher than 30 mg/m3 (NOAEC). Starting from this value, a DNEL of 0,15 mg/m3 was derived using an assessment factor of 200 calculated as follows: - 10 for intraspecies variability - 10 for interspecies variability - 2 for accounting of differences in daily duration of exposure (4 h/day in animals, 8 h/day workers). Whilst the substance is acutely hazardous by inhalation (it is classified as STOT SE 2), a reliable D(M)NEL cannot be identified from the available data. The ...
NOTE: Update in Progress. Epidemiology. Organisms of the Mycobacterium avium complex (MAC) are ubiquitous in the environment.1-3 M. avium is the etiologic agent in ,95% of patients with AIDS who acquire disseminated MAC disease.1,4-9 An estimated 7% to 12% of adults have been previously infected with MAC, although rates of disease vary in different geographic locations.1,5,8,9 Although epidemiologic associations have been identified, no environmental exposure or behavior has been consistently linked to subsequent risk of developing MAC disease.. The mode of transmission is thought to be through inhalation, ingestion, or inoculation via the respiratory or gastrointestinal tract. Household or close contacts of those with MAC disease do not appear to be at increased risk of disease, and person-to-person transmission is unlikely.. MAC disease typically occurs in patients with CD4 T lymphocyte (CD4) cell counts ,50 cells/mm3. The incidence of disseminated MAC disease is 20% to 40% in patients with ...