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There are inherent challenges in scaling stomatal conductance (g s) from leaf to canopy particularly over seasonal time scales when species distribution and canopy structure evolve. We address this gap using carbonyl sulfide (OCS) and CO 2 fluxes from a predominantly C3 prairie and C4 maize field in the midwestern United States. The g s derived from OCS fluxes captured a transition in the stomatal limitation on gross primary productivity (GPP) through the growing season as well as seasonally persistent g s dynamics such as temperature optimum and a positive response of nighttime g s to vapor pressure deficit. Near the termination of the prairie growing season, we observed a decrease in the relative OCS to CO 2 flux that we hypothesize emerged from a rising contribution of C4 plants to productivity. The results show how plot‐scale OCS and CO 2 fluxes can be used as a trace gas diagnostic for transitions in the limiting factors for community GPP. Key Points: Canopy stomatal conductance was derived from carbonyl sulfide (OCS) fluxes at maize and prairie sites in the midwestern United StatesSeasonal changes in the ratio of canopy stomatal conductance to GPP elucidated phenological transitions in community photosynthesisDaytime and nighttime OCS and CO 2 fluxes can be used for diagnostic trace gas signatures associated with C3 and C4 productivity [ABSTRACT FROM AUTHOR]

Phototrophic communities forming in the bottom of the Berikei highly mineralized mesothermal sulfide springs (Kayakent region, Dagestan, Russia) were investigated. The Berikei springs are an interesting example of combined effect of such factors as temperature, salinity, pH, and sulfide of occurrence and structure of phototrophic microbial communities. The water was of the sodium chloride type with salinity of 48‒97 g/L, near-neutral brine pH, and sulfide concentration of ~1 mM. The temperature at the stream bottom was as high as 60°C. Elevated temperature and high salinity limited the development of phototrophic communities. Formation of cyanobacterial mats occurred at temperatures below 54°C. Phormidium-like cyanobacteria and unicellular Synechocystis sp. predominated in the mats. The number of cyanobacterial species increased at desalination to 48‒57 g/L with emergence of the species morphologically resembling Spirulina sp., Leptolyngbya sp., and Oscillatoria sp. Among anoxygenic phototrophic bacteria, halophilic purple bacteria Ectothiorhodospira sp., Marichromatium sp., and Rhodovulum sp., green sulfur bacteria Prosthecochloris sp., and unidentified Chloroflexi were present. Oxygenic photosynthesis in the mats was not inhibited by sulfide. Production of cyanobacterial mats was up to 4.7‒53.8 µg/(cm2 h). The contribution of anoxygenic phototrophic bacteria to photosynthetic production varied from 0 to 100%. The composition of this microbial community was compared to those of the phototrophic microbial communities of the mesothermal springs of the Dead Sea coast (Israel), the Washington warm lake (United States), and the Paoha Island hot springs (Mono Lake, United States. [ABSTRACT FROM AUTHOR]

Breast cancer is the second leading cause of cancer deaths in women in the United States. Diethylstilbestrol (DES) is a synthetic estrogen that has been shown to cause cancer in animals and humans, altering cell viability as well as inducing DNA damage. Diallyl sulfide (DAS) is a garlic organosulfide that has been shown to inhibit both the initiation and promotion phases of cancer in vivo and in vitro , as well as reduce the risk of cancer in epidemiological studies. MCF-10A cells, regarded as a normal breast epithelial cell line, were treated with varying concentrations of DES, DAS or various dose combinations of DES and DAS concomitantly, and assessed for cell viability, DNA strand breaks, and lipid peroxidation. DES (10 μM) in combination with 1, 10, or 100 μM DAS resulted in a 31%, 34%, or 36% respective increase in cell viability compared to the DES treatment alone, after 24 h. At the same time point, 1, 10, and 100 μM DAS were all effective in significantly reducing DES (100 μM)-induced strand breaks to near that of the vehicle control. Additionally, 1 μM DAS was effective in significantly reducing DES (100 μM)-induced lipid peroxidation after 3 h. The results of this research suggest that DAS is effective in recovering cell viability, attenuating DNA strand breaks, and decreasing lipid peroxidation in MCF-10A cells. [ABSTRACT FROM AUTHOR]

Methane mitigation from the oil and gas (O&G) sector represents a key near-term global climate action opportunity. Recent legislation in the United States requires updating current methane reporting programs for oil and gas facilities with empirical data. While technological advances have led to improvements in methane emissions measurements and monitoring, the overall effectiveness of mitigation strategies rests on quantifying spatially and temporally varying methane emissions more accurately than the current approaches. In this work, we demonstrate a quantification, monitoring, reporting, and verification framework that pairs snapshot measurements with continuous emissions monitoring systems (CEMS) to reconcile measurements with inventory estimates and account for intermittent emission events. We find that site-level emissions exhibit significant intraday and daily emission variations. Snapshot measurements of methane can span over 3 orders of magnitude and may have limited application in developing annualized inventory estimates at the site level. Consequently, while official inventories underestimate methane emissions on average, emissions at individual facilities can be higher or lower than inventory estimates. Using CEMS, we characterize distributions of frequency and duration of intermittent emission events. Technologies that allow high sampling frequency such as CEMS, paired with a mechanistic understanding of facility-level events, are key to an accurate accounting of short-duration, episodic, and high-volume events that are often missed in snapshot surveys and to scale snapshot measurements to annualized emissions estimates.

In the United States, the Bald and Golden Eagle Protection Act prohibits take of golden eagles (Aquila chrysaetos) unless authorized by permit, and stipulates that all permitted take must be sustainable. Golden eagles are unintentionally killed in conjunction with many lawful activities (e.g., electrocution on power poles, collision with wind turbines). Managers who issue permits for incidental take of golden eagles must determine allowable take levels and manage permitted take accordingly. To aid managers in making these decisions in the western United States, we used an integrated population model to obtain estimates of golden eagle vital rates and population size, and then used those estimates in a prescribed take level (PTL) model to estimate the allowable take level. Estimated mean annual survival rates for golden eagles ranged from 0.70 (95% credible interval = 0.66-0.74) for first-year birds to 0.90 (0.88-0.91) for adults. Models suggested a high proportion of adult female golden eagles attempted to breed and breeding pairs fledged a mean of 0.53 (0.39-0.72) young annually. Population size in the coterminous western United States has averaged ~31,800 individuals for several decades, with λ = 1.0 (0.96-1.05). The PTL model estimated a median allowable take limit of ~2227 (708-4182) individuals annually given a management objective of maintaining a stable population. We estimate that take averaged 2572 out of 4373 (59%) deaths annually, based on a representative sample of transmitter-tagged golden eagles. For the subset of golden eagles that were recovered and a cause of death determined, anthropogenic mortality accounted for an average of 74% of deaths after their first year; leading forms of take over all age classes were shooting (~670 per year), collisions (~611), electrocutions (~506), and poisoning (~427). Although observed take overlapped the credible interval of our allowable take estimate and the population overall has been stable, our findings indicate that additional take, unless mitigated for, may not be sustainable. Our analysis demonstrates the utility of the joint application of integrated population and prescribed take level models to management of incidental take of a protected species., (© 2022 The Authors. Ecological Applications published by Wiley Periodicals LLC on behalf of The Ecological Society of America. This article has been contributed to by US Government employees and their work is in the public domain in the USA.)

- We present NanoSIMS four-isotope S analyses of 24 comet Wild 2 dust impact residues in craters on aluminum foil C2037N returned by NASA's Stardust mission. Except for one sample, all impact residues have normal S isotopic compositions within 2σ uncertainties of at least two S isotope ratios. This implies that most S-rich Wild 2 dust impactors formed in the solar system. Instrumental isotope fractionation due to sample topography is the main contribution to our analytical uncertainty. One impact crater residue shows small anomalies of δ33S = −57 ± 17‰, and δ34S = −41 ± 17‰ (1σ uncertainties). Although this could be simply a statistical outlier or the fingerprint of a chemical isotope fractionation it is also possible that the observed anomaly results from the mixture of a cometary FeS particle with a small (150 nm diam.) presolar FeS supernova grain. This would translate into a presolar sulfide abundance of approximately 200 ppm. [ABSTRACT FROM AUTHOR]

Abstract: The discovery of natural 210Po enrichment at levels exceeding 500mBq/L in numerous domestic wells in northern Nevada, USA, led to a geochemical investigation of the processes responsible for its mobilization. 210Po activities in 63 domestic and public-supply wells ranged from below 1mBq/L to 6590±590mBq/L, among the highest reported levels in the USA. There is little spatial or depth variability in 210Pb activity in study-area sediments and mobilization of a few percent of the 210Po in the sediments would account for all of the 210Po in water. Stable-isotope measurements indicate SO4 reduction has occurred in all 210Po contaminated wells. Sulfide species are not accumulating in the groundwater in much of Lahontan Valley, probably because of S cycling involving microbial SO4 reduction, abiotic oxidation of H2S to S0 by Mn(IV), followed by microbial disproportionation of S0 to H2S and SO4. The high pH, Ca depletion, MnCO3 saturation, and presence of S0 in Lahontan Valley groundwater may be consequences of the anaerobic S cycling. Consistent with data from naturally-enriched wells in Florida, 210Po activities begin to decrease when aqueous sulfide species begin to accumulate. This may be due to formation and precipitation of PoS, however, Eh–pH diagrams suggest PoS would not be stable in study-area groundwater. An alternative explanation for the study area is that H2S accumulation begins when anaerobic S cycling stops because Mn oxides are depleted and their reduction is no longer releasing 210Po. Common features of 210Po-enriched groundwater were identified by comparing the radiological and geochemical data from Nevada with data from naturally-enriched wells in Finland, and Florida and Maryland in the USA. Values of pH ranged from <5 in Florida wells to >9 in Nevada wells, indicating that pH is not critical in determining whether 210Po is present. Where U is present in the sediments, the data suggest 210Po levels may be elevated in aquifers with (1) SO4-reducing waters with low H2S concentrations, or (2) anoxic or oxic waters with extremely high Rn activities, particularly if the water is turbid. [Copyright &y& Elsevier]

Abstract: Detailed iron, sulfur and carbon chemistry through the >742million year old Chuar Group reveals a marine basin dominated by anoxic and ferrous iron-rich (ferruginous) bottom waters punctuated, late in the basin''s development, by an intrusion of sulfide-rich (euxinic) conditions. The observation that anoxia occurred frequently in even the shallowest of Chuar environments (10s of meters or less) suggests that global atmospheric oxygen levels were significantly lower than today. In contrast, the transition from ferruginous to euxinic subsurface water is interpreted to reflect basinal control—specifically, increased export of organic carbon from surface waters. Low fluxes of organic carbon into subsurface water masses should have been insufficient to deplete oxygen via aerobic respiration, resulting in an oxic oxygen minimum zone (OMZ). Where iron was available, larger organic carbon fluxes should have depleted oxygen and facilitated anaerobic respiration using ferric iron as the oxidant, with iron carbonate as the expected mineralogical signature in basinal shale. Even higher organic fluxes would, in turn, have depleted ferric iron and up-regulated anaerobic respiration by sulfate reduction, reflected in high pyrite abundances. Observations from the Chuar Group are consistent with these hypotheses, and gain further support from pyrite and sulfate sulfur isotope abundances. In general, Chuar data support the hypothesis that ferruginous subsurface waters returned to the oceans, replacing euxinia, well before the Ediacaran emergence of persistently oxygenated conditions, and even predating the Sturtian glaciation. Moreover, our data suggest that the reprise of ferruginous water masses may relate to widespread rifting during the break-up of Rodinia. This environmental transition, in turn, correlates with both microfossil and biomarker evidence for an expanding eukaryotic presence in the oceans, suggesting a physiologically mediated link among tectonics, environmental chemistry and life in the dynamic Neoproterozoic Earth system. [Copyright &y& Elsevier]

Abstract: Coastal areas in the southeastern USA are prone to hurricanes and strong storms that may cause salt-water influx to freshwater aquatic sediments. These changes in environmental conditions may impact sediment processes including nitrogen (N) cycling. The relative abilities of sediment microbial communities from two freshwater golf course retention ponds that drain into the adjacent wetlands, and two proximal saline wetland ponds, to remove nitrate (NO3 −) were compared to assess whether low concentrations of sulfide changed N-transformation processes. Microcosms were incubated with NO3-N (300 μg g dw−1) alone, and with NO3-N and sulfide (H2S) (100 and 200 μg g dw−1). Nitrous oxide (N2O), nitrite (NO2 −), NO3 −, ammonium (NH4 +), SO4 2− and acid volatile sulfides were analyzed over time. The acetylene block technique was used to measure denitrification in sediment microcosms with no added H2S. Denitrification was measured without acetylene (C2H2) addition in microcosms with added H2S. With no added H2S, denitrification was greater in the freshwater retention ponds than in the wetland ponds. Although low H2S concentrations generally increased NO3-N removal rates at all sites, lag periods were increased and denitrification was inhibited by low sulfide in the freshwater sediments, as evidenced by the greater concentrations of N2O that accumulated compared to those in the wetland sediments. In addition to the inability of the freshwater sediments to convert N2O to N2 in the absence of C2H2, anomalously high transient NO2-N concentrations accumulated in the retention pond samples. NH4-N formation generally decreased due to H2S addition at the freshwater sites; NH4-N formation increased initially at the wetland sites, but was greater when no H2S was added. Storm events that allow influx of SO4 2−-containing seawater into freshwater systems may change the dominant N species produced from nitrate reduction. Even low concentrations of sulfide produced incomplete denitrification and decreased formation of NH4 + in these coastal freshwater sediments. [Copyright &y& Elsevier]

Discusses the sources of realgar arsenic sulfide. Description of realgar; Conditions where the mineral occurs; Pegmatite localities where realgar is found.

The Figueroa sulfide deposit located in Franciscan Complex rocks in the San Rafael Mountains, California, contains the only known Jurassic hydrothermal vent community. Based on radiolarian biostratigraphy it is Pliensbachian (early Jurassic) in age. The Figueroa fossil organisms lived at a deepwater, high temperature vent site located on a mid-ocean ridge or seamount at an equatorial latitude. The vent site was then translated northeastward by the motion of the Farallon Plate and was subsequently accreted to its present location. The vent fossils are preserved as molds of pyrite and there is no remaining shell or tube material. The fossil assemblage is specimen rich, but of low diversity, and comprises, in order of decreasing abundance, vestimentiferan worm tubes, rhynchonellide brachiopods (Anarhynchia cf. gabbi), and trochoidean gastropods (Francisciconcha maslennikovi new genus and species). These fossils represent only primary consuming organisms, some of which may have had chemosynthetic microbial endosymbionts, like many modern dominant vent animals. The Figueroa vent assemblage shares vestimentiferan tube worms and gastropods with other fossil and modern vent communities, but is unique in having rhynchonellide brachiopods. It shares this feature with contemporary Mesozoic cold seep communities. Many other taxonomic groups found at modern vent sites are missing from the Figueroa assemblage. The presence of vestimentiferan tube worm fossils in the Figueroa deposit is at odds with the supposed time of origin of the modern vestimentiferans (∼100 Ma), based on molecular data. [ABSTRACT FROM AUTHOR]

Focuses on zinc sulfide scale found in oil fields along the Gulf Coast of the U.S. and North Sea Basin. Potential sources of lead and zinc sulfide; Common mineral scales encountered in oil field operations; Scale inhibitors tested in the study for effectiveness against zinc sulfide.

Presents a study which investigated the characteristics of native gold found in fresh basanite glass from the early submarine phase of Kilaue in Hawaii. Discovery and occurrence of gold in the area; Composition of native gold; Discussion on sulfide stability and gold transport.

A simple and reliable technique has been developed and used to detect odorous gases, i.e. propionic and butyric acids, carbon disulfide, dimethyl sulfide, dimethyl disulfide, and trimethylamine, emitted from various materials generated by the wastewater treatment process. The method detection limits are in the low ppb range and comparable to the odor threshold for human detection. In this study solid phase microextraction (SPME) was employed to characterize and quantify odorous compounds in the headspace over samples collected from various unit processes at the District of Columbia Wastewater Treatment Plant, Washington DC, USA. The patterns of odorous chemicals released from wastewater influent, thickened sludge, dewatered sludge and biosolids were evaluated. Volatile reduced sulfurs were more prevalent in samples collected from downstream processes and corresponded with decreased oxidation-reduction potential (ORP) conditions. Volatile fatty acids were consistently identified in the primary gravity thickeners, while trimethylamine could only be detected from biosolids after the post-liming process. [ABSTRACT FROM AUTHOR]

New Re-Os molybdenite dates from two lode gold deposits of the Tintina Gold Belt, Alaska, provide direct timing constraints for sulfide and gold mineralization. At Fort Knox, the Re-Os molybdeulte date is identical to the U-Pb zircon age for the host intrusion, supporting an intrusive-related origin for the deposit. However, [sup 40]Ar/[sup 39]Ar dates from hydrothermal and igneous mica are considerably younger. At the Pogo deposit, Re-Os molybdenite dates are also much older than [sup 40]Ar/[sup 39]Ar dates from hydrothermal mica, but dissimilar to the age of local granites. These age relationships indicate that the Re-Os molybdenite method records the timing of sulfide and gold mineralization, whereas much younger [sup 40]Ar/[sup 39]Ar dates are affected by post-ore thermal events, slow cooling, and/or systemic analytical effects. The results of this study complement a growing body of evideuce to indicate that the Re-Os chronometer in molybdenite can be an accurate and robust tool for establishing timing relations in ore systems. [ABSTRACT FROM AUTHOR]

The U.S. Food and Drug Administration (FDA) became aware of postmarketing reports of neuropsychiatric adverse events with Singulair (montelukast) use in 2007. Over the years, the FDA has conducted reviews of the clinical trial safety data, focused analyses of postmarketing reports, and reviews of the published literature. These activities have resulted in successive labeling updates and public communications. However, there has been continued concern among stakeholders about the risk of neuropsychiatric events and the lack of awareness among prescribers and patients/caregivers. On the basis of these concerns, the FDA embarked on another comprehensive review and also conducted a new observational study using claims data in the Sentinel Distributed Database. In September 2019, the FDA held a public Advisory Committee meeting to discuss its review and solicit recommendations from the panel regarding labeling and communication strategies. After careful consideration of the available data and feedback received during the FDA Advisory Committee meeting, the FDA required a boxed warning and a revision specifically for the allergic rhinitis indication to reserve use of montelukast to patients who have an inadequate response or intolerance to alternative therapies. Based on benefit-risk considerations, the asthma indication was not changed. To provide insight into the process and rationale for the required labeling changes, we provide an overview of the decision-making framework we used., (Copyright © 2021 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.)

The article reports on the significance of hydrogen sulfide (H2), the rotten egg gas, to the medical industry in the U.S. It is characterized as a foul-smelling, corrosive, flammable and deadly chemical wherein a single breath of it can kill a person. Scientists are undertaking research to discover its medical value. Despite its distinctive smell and toxicity, scientists discovered that it starves ones cells by disabling an enzyme necessary for the extraction of energy from food and proves to be an influential physiological signal that can affect everything ranging from the blood flow to hormone secretion. Because of such discovery, they are eager to exploit the chemical to tame the side effects of common painkillers and curb heart attack damage.

Background: Daratumumab is a human CD38-directed monoclonal antibody indicated for the treatment of relapsed and refractory multiple myeloma (MM)., Methods: A multicenter, open-label treatment protocol provided early access to daratumumab for patients who had progressive MM after they received ≥3 prior lines of therapy that included a proteasome inhibitor and an immunomodulatory agent or if they were refractory to both a proteasome inhibitor and an immunomodulatory agent. Patients received daratumumab 16 mg/kg weekly for 8 weeks, every other week for 16 weeks, and monthly until they developed disease progression, unacceptable toxicity, or 60 days after the drug gained US approval. Treatment-emergent grade ≥3 adverse events (AEs), serious AEs, and AEs of special interest were collected., Results: Three hundred forty-eight patients were enrolled at 39 US sites between June and December 2015. Patients received study therapy for a median of 1.9 months (range, 0.03-6.0 months). Fifty-two percent of patients transitioned to commercially-available daratumumab and 37% discontinued because of progressive disease. Grade ≥3 AEs occurred in 50% of patients, including thrombocytopenia (15%) and anemia (14%). Serious AEs occurred in 35% of patients (12% were drug-related), including infections (11%). Infusion reactions occurred in 56%, 2%, and 2% of patients during the first, second, and all subsequent infusions, respectively; respiratory symptoms (cough, dyspnea, throat irritation, nasal congestion) were common. The infusion reaction rate for the first infusion was 38% in 50 patients at 2 sites who received montelukast as premedication for their first infusion and 59% in patients who did not receive montelukast., Conclusions: The current findings are consistent with previously reported trials and confirm the safety profile of daratumumab in heavily pretreated US patients who have relapsed or refractory MM. Cancer 2018;124:000-000., (© 2018 The Authors. Cancer published by Wiley Periodicals, Inc. on behalf of American Cancer Society.)

Rationale: The natural history of lung function in patients with bronchiolitis obliterans syndrome (BOS) after allogeneic hematopoietic cell transplant is poorly characterized. Understanding the trajectory of lung function is necessary for prompt clinical recognition and treatment and also for the rational design of prospective studies., Objectives: To describe the longitudinal trajectory of lung function parameters, including FEV 1 , in patients with BOS after hematopoietic cell transplant., Methods: Subjects with BOS defined by National Institutes of Health consensus guidelines criteria from a recent multicenter prospective trial of combination treatment with fluticasone, azithromycin and montelukast and a retrospective cohort from Fred Hutchinson Cancer Research Center were included. Longitudinal change in FEV 1 for each patient was calculated on the basis of available pulmonary function tests in three periods: pre-BOS, from BOS diagnosis to 6 months, and 6-18 months after diagnosis. The effect of treatment on FEV 1 trajectory was analyzed by univariate and multivariate linear regression. The Kaplan-Meier method was used to estimate survival., Measurements and Main Results: The FEV 1 percent predicted value at diagnosis was 46% (interquartile range, 35-57%) for trial participants and 53% (interquartile range, 41-64%) for the retrospective cohort. There was a concomitant mild reduction in FVC, as well as a marked reduction in forced expiratory flow, midexpiratory phase, at diagnosis. While there was individual heterogeneity, the overall FEV 1 trajectory was characterized by a marked decline within 6 months prior to BOS diagnosis, followed by stability of FEV 1 early after diagnosis and a slow rate of decline beyond 6 months. The effect of the trial medications on FEV 1 trajectory after BOS diagnosis was a mean rate of change of 0.92% predicted per month (95% confidence interval, -0.53 to 2.37) compared with the retrospective cohort, but this was not statistically significant. Two-year overall survival rates were 76% and 72% for the study participants and the retrospective cohort patients, respectively. Earlier time to diagnosis after hematopoietic cell transplant and severity of FVC at diagnosis were significantly associated with reduced survival., Conclusions: The FEV 1 trajectory in patients with BOS after hematopoietic cell transplant in a contemporary era of management follows a predominant pattern of rapid FEV 1 decline in the 6 months prior to diagnosis, followed by FEV 1 stabilization after diagnosis.

Background: In 2013, the Agency for Healthcare Research and Quality (AHRQ) recommended that allergic rhinitis (AR) studies calculate a minimal clinically important difference (MCID) based on an estimated threshold equal to 30% of the maximum total nasal symptom score. Applying this threshold, their data showed no differences between well-established treatments, and a subsequent analysis using prescribing information found no differences between active treatments and placebo controls., Objective: The objective of this study was to demonstrate the application of an evidence-based model to determine MCIDs for AR studies, with an absolute value for an anchor-based threshold and validated methods for calculating distribution-based thresholds., Methods: Using the same studies as the AHRQ report, anchor- and distribution-based MCID thresholds were determined for 3 clinical comparisons identified by the AHRQ: (1) oral antihistamine+intranasal corticosteroid (INCS) versus INCS, (2) montelukast versus INCS, and (3) intranasal antihistamine+INCS in a single device versus the monotherapies. The outcomes were compared with those reported using the AHRQ threshold., Results: No treatment comparison met the AHRQ-defined MCID threshold; all treatments were determined to be equivalent for all 3 queries. In contrast, the evidence-based model revealed some differences between treatments: INCS > montelukast; intranasal antihistamine+INCS > either monotherapy. No clinically relevant benefit was observed for adding an oral antihistamine to INCS, but some studies were not optimal choices for quantitative determination of MCIDs. Updating the literature search revealed no additional studies that met the AHRQ inclusion criteria., Conclusions: The evidence-based threshold for MCID determination for AR studies should supersede the threshold recommended in the AHRQ report., (Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.)

The article reports on scientists from National Aeronautics and Space Administration (NASA) testing theories about the composition and formation of the early solar system. The success of NASA's Stardust mission, which returned material from comet Wild-2, is helping these scientists for their investigation. So far, scientists have identified glassy and crystalline compounds, including iron sulfides. Although sulfides were not unexpected, there had been no spectral evidence that comets contain sulfur. Mission scientists have also found hints of organic matter and so-called glass embedded with metal and sulfides. Comets originated at the periphery of the rotating cloud of gas and dust that formed the solar system and likely retain pristine material from that time.

Purpose: The purpose of the study was to survey program directors of postdoctoral prosthodontic programs in the United States regarding their programs' complete denture impression techniques. The key objectives of the survey were to identify the current trends in complete denture impression making and to determine which techniques and materials are taught in US postdoctoral prosthodontic programs., Materials and Methods: An online survey was sent to all program directors of US postdoctoral prosthodontic programs. The survey comprised two sections: preliminary impressions and final impressions. The survey contained 22 questions that would take approximately 5 minutes to complete. All responses remained anonymous throughout the survey., Results: The response rate for the survey was 87%. A majority of the programs did not separately border mold the tray prior to making the preliminary impressions (82%). The impression material of choice for the preliminary impression was irreversible hydrocolloid (88%). Selective pressure was the predominantly used impression philosophy (80%). All programs border molded the custom tray, and 95% recorded the borders in sections. The material of choice for border molding the custom tray was modeling plastic impression compound (71%). The most commonly used impression material for the final impressions was polyvinylsiloxane (PVS) (42%), and the second most commonly used impression material was polysulphide (32%). The most common technique for locating the posterior palatal seal was marking intraorally and transferring onto the final impression (65%). Most programs routinely advised their patients not to wear their existing dentures for at least 24 hours before the final impressions were made (83%)., Conclusions: Based on the results of this study, the following conclusions can be drawn: (1) The most commonly used material for the preliminary impression was irreversible hydrocolloid and for the final impression was PVS. (2) Modeling plastic impression compound was used by most programs to border mold the custom trays. (3) Selective pressure was the predominantly used impression philosophy. (4) A majority of the programs made a special consideration for excessive movable (flabby) tissue. (5) Most programs routinely advised their patients to not wear their existing dentures for at least 24 hours before the final impressions were made., (© 2013 by the American College of Prosthodontists.)

Background: Public policymakers often struggle with increased membership and limited budgets. Restrictions, commonly in the form of prior authorizations, are often placed on more costly pharmaceuticals, especially when lower cost or more effective products are available. Restrictions placed on products for difficult-to-manage disease states must be reviewed in order to ensure that unintended clinical consequences do not occur., Objective: To assess the impact of a prior authorization policy for montelukast on clinical outcomes for asthma and allergic rhinitis among children and adolescent members of Oklahoma Medicaid (MOK) from 2007 through 2010., Methods: Monthly individual-level utilization data were collected from MOK paid pharmacy and medical claims from January 1, 2007, through December 31, 2010, for members with asthma and/or allergic rhinitis. Members who were continuously eligible for the entire 48-month review period were included. The effect of a prior authorization policy for montelukast on emergency room (ER) utilization, disease-related physician office visits (DRV), and antibiotic prescription utilization (ABX) was analyzed using segmented logistic regression., Results: For all 3 outcomes, decreases in mean number of claims per member per month were detected when comparing the pre-implementation and post-implementation prior authorization periods for all 3 disease states of asthma, allergic rhinitis, or both. Odds of having an ER event at the point of prior authorization implementation were 0.71 (P  less than  0.001) and were 1.29 (P  less than  0.001) and 1.26 (P  less than  0.001) for DRV and ABX, respectively. Overall trend in odds was 1.02 (P  less than  0.001), 0.93 (P  less than  0.001), and 0.95 (P  less than  0.001) for ER, DRV, and ABX, but during the post-implementation period, the odds were 0.92 (P  less than  0.001) for ER and 1.03 (P  less than  0.001) for both DRV and ABX. The final result was an increasing trend prior to implementation for ER, a decrease at implementation, and a continued decrease in odds of an event in the post-implementation period. However, for DRV and ABX, there was an overall decrease in trend regardless of period, with a small increase in odds at the point of implementation., Conclusions: While there was a point increase at implementation for DRV and ABX, the overall trend remained negative, indicating that no unexpected adverse clinical outcomes occurred. Additionally, no signal was found in ER use after implementation to indicate that unintended consequences occurred, particularly for those patients with asthma.

The US FDA has issued safety alerts and required manufacturers of leukotriene-modifying agents (LTMAs), including montelukast, zafirlukast and zileuton, to include suicide and neuropsychiatric events as a precaution in the drug label. This paper reviews the existing evidence on the potential association between the LTMAs and suicidal behaviour. We conducted a literature search of MEDLINE, EMBASE and International Pharmaceutical Abstracts from 1995 to 2010 (inclusive) to identify pertinent studies and reports. We also examined data obtained from the FDA adverse event reporting system. To date, there are no well conducted, comparative, observational studies of this association, and the safety alerts are based primarily on case reports. While the FDA safety alerts apply to all three LTMAs, montelukast (known by its trade name Singulair®) is by far the most widely used of these drugs and most of the reports to date regarding suicide pertain to montelukast. From 1998 to 2009 there were 838 suicide-related adverse events associated with leukotrienes reported to the FDA, of which all but five involved montelukast. Nearly all cases were reported in 2008 and 2009 (96.1%) after the FDA warnings. LTMAs are approved for use in asthma and allergic rhinitis, and are effective drugs. Both of these diseases are also associated with suicide, making confirmation of the association more difficult. Given the lack of good evidence, we recommend that a large observational cohort or case-control study be conducted to quantify the association between LTMAs and suicide. Until then, when prescribing LTMAs, clinicians should consider the potential for suicide and monitor patients who may be at elevated risk carefully for suicidal ideation or psychiatric symptoms associated with suicidal behaviour.

Background: The efficacy of oral montelukast in chronic asthma is well established. Montelukast is also an effective adjunctive therapy to inhaled corticosteroids (ICS) in asthma uncontrolled on ICS alone. Inhaled montelukast was recently shown to provide significant bronchodilation compared with placebo in patients with chronic asthma. The purpose of this study was to evaluate the efficacy of inhaled montelukast added to inhaled mometasone., Methods: This was an 8-week, multicenter, randomized, double-blind, placebo-controlled study comparing once-daily inhaled montelukast 1 mg plus inhaled mometasone 220 μg (delivered by separate dry powder inhalers) with placebo plus inhaled mometasone 220 μg. Men and women aged 15-85 years with chronic asthma, forced expiratory volume in 1 second (FEV(1)) 50-80% of the predicted value, and β-agonist reversibility ≥12% were eligible. Patients were required to meet a minimum symptom threshold while receiving open-label inhaled mometasone during a 3-week prestudy/run-in period. Patients received blinded (montelukast vs. placebo) treatment for 2 weeks, entered a 1-week washout period, then crossed over to the other treatment for 2 weeks. The primary endpoint was the average change from baseline in FEV(1) over the 2-week treatment period. Secondary endpoints included daytime and nighttime symptom scores. Other endpoints included short-acting β-agonist (SABA) use, asthma exacerbations, asthma control, peak expiratory flow (PEF), and blood eosinophil count., Results: A total of 134 patients were randomized. For the primary endpoint, change from baseline in FEV(1), inhaled montelukast plus inhaled mometasone was significantly more effective than placebo plus inhaled mometasone (least squares mean 0.22 L vs. 0.17 L; p = .033 [two-sided at α = 0.05]). Inhaled montelukast plus inhaled mometasone was also significantly more effective than placebo plus inhaled mometasone in improving daytime asthma symptom scores (p = .005) and nighttime asthma symptom scores (p = .015), increasing the percentage of days with asthma control (p = .004), decreasing the percentage of days with asthma exacerbations (p ≤ .001), and decreasing the blood eosinophil count (p = .013). Differences were not significant on AM or PM PEF or SABA use, although the latter approached significance (p = .073). Both treatments were well tolerated., Conclusion: Inhaled montelukast plus inhaled mometasone was significantly more effective than placebo plus inhaled mometasone in improving FEV(1), symptoms, asthma control, and blood eosinophil count.

Objective: The objective of this study was to analyse inter-and intra-country quantitative and qualitative differences in anti-asthmatic prescriptions to children and adolescents., Methods: A literature search was performed in EMBASE and MEDLINE to identify pharmaco-epidemiological studies published from January 1, 2000 to December 31, 2008 in which anti-asthmatic prescription prevalence in out-hospital children was measured. A meta-analytic weighted average and 95% confidence intervals of prescription prevalences were calculated using a random-effect(s) model. Inter- and intra-country quantitative and, where possible, qualitative prescribing patterns were compared and assessed., Results: Twelve studies were identified (ten from Europe, one from Canada and one from the USA), but epidemiological indicators varied widely, and only eight were suitable for meta-analysis. The data from these studies revealed inter-country quantitative differences in prescription prevalences in the overall population

This study evaluates the costs and utilization burden associated with oral, branded second-generation antihistamines (BSGAs) compared with montelukast (MTLK) as first-choice treatment in newly diagnosed allergic rhinitis (AR) patients without asthma. We compared annual medical costs of illness and utilization changes from 1 year before index AR diagnosis to 1 year after for continuously enrolled AR patients initiating therapy with BSGA or MTLK. Multivariate regressions for each outcome variable adjusted for confounders including age, sex, geographic region, Charlson Comorbidity Index, RxRisk Score, 18 comorbidity groups, and payer type. Treatment selection bias was evaluated by propensity score with all covariates plus instrumental variables including physician type and likelihood of prescribing MTLK versus BSGA. Insurance claims data for the years 2003-2007 included AR patients in all regions of the United States. The final sample included 13,703 AR patients taking BSGAs (84%) or MTLK (16%). After confounder adjustment, MTLK patients experienced higher total medical costs ($1,542 versus $989), drug costs ($714 versus $477), AR drug costs ($474 versus $298), and outpatient visit costs ($480 versus $277) than BSGA patients (all values of p < 0.025). MTLK patients experienced higher total visits (0.96), AR outpatient visits (0.71), and comorbidity visits (0.12) than BSGA patients (all values of p < 0.01). MTLK patients were more likely to add additional AR therapy medications (MTLK, 43.2%; BSGA, 31.6%; p < 0.01). New AR patients prescribed MTLK as first-line medication therapy have higher medical costs and resource utilization than those prescribed first-line oral BSGAs. These differences persisted after adjustment for patient fixed effects, available confounders, and treatment propensity scores.

Recurrent wheezing is common in preschool-aged children, with 1 in 3 children experiencing at least 1 acute wheezing illness before the age of 3 years. These children represent a diverse group, with some going on to present with asthma at school age and others experiencing complete resolution of symptoms. The primary care physician is faced with a dilemma of when to recommend daily therapy. He or she must also answer parents' concerns, often expressed as, "Does my child have asthma?" and "Will my child have to take medication the rest of his or her life?" This article presents recent studies and recommendations that can guide the physician in approaching the child and the parent with rational management. The emphasis is on viewing recurrent wheezing as a continuum requiring a plan of monitoring that starts with the very first episode. Using background information from the parents and a history of the child's allergic disposition, one can discuss with parents the risks of developing asthma and, together with planned monitoring, prescribe appropriate management. The primary care physician can plan management by using the Asthma Predictive Index and employing specific questions for features present during the intervals between acute episodes. Together with close monitoring, the physician will have a compass that effectively directs rational management.

Historically, rhinitis has been perceived by many clinicians in respiratory medicine as an unimportant condition. The purpose of this study was to evaluate physicians' perceptions of the impact of allergic rhinitis and chronic or nonallergic rhinitis on patients' health. This cross-sectional survey involved U.S. physicians identified from a claims database as treating patients with allergic rhinitis or chronic rhinitis during a 13-month period. Responses were stratified by physicians' overall assessment of their patients' rhinitis severity, presence or absence of an allergy specialist at the practice, and agreement or disagreement that allergic rhinitis and nonallergic rhinitis should be managed similarly. Of 2614 physicians invited to participate, 766 responded. Physicians who perceived the majority of their patients as having moderate-to-severe symptoms were more likely to be prescribed more than one class of medication and physicians whose patients had mostly mild symptoms were more likely to recommend nonprescription products. Physicians whose practice included an allergy specialist compared with physicians without an allergy specialist at their practice were more likely to report that higher percentages of their patients were prescribed more than one class of medication, more likely to rate patients' descriptions of symptom severity and quality-of-life-related issues as extremely important in treatment decisions, and less likely to believe that allergic rhinitis and nonallergic rhinitis have the same symptoms. Physicians who did not agree that allergic rhinitis and nonallergic rhinitis should be managed similarly were more likely to prescribe more than one class of medication and to rate patients' descriptions of symptom severity and quality-of-life impact as extremely important in their treatment decisions. This physician survey provides insight into perceptions of the impact of allergic rhinitis and nonallergic rhinitis on patients' quality of life and symptom severity.

In a study comparing low-dose theophylline to montelukast in poorly controlled asthmatics, 285 subjects consented to be screened for alpha-1 antitrypsin deficiency. Of the 284 for which complete data was available, 10.5% carried a deficiency gene and 2.4% were mildly deficient with an alpha-1 antitrypsin serum level of less than 20 mu M. In the non-African-American cohort, an abnormal phenotype occurred in 12% and 2.9% were mildly deficient. Baseline pulmonary function and asthma scores were not significantly different between those with normal and abnormal AAT phenotype. However those with the deficiency tended to show a greater bronchodilator response.

Purpose: The purpose of this study was to survey members of The American College of Prosthodontists (ACP) to evaluate current materials and methods for final impressions for complete denture prosthodontics in the United States. In addition, those methods were compared with methods and materials taught in U.S. dental schools via a second survey sent to the chairpersons of prosthodontic/restorative departments., Materials and Methods: An anonymous questionnaire was mailed to all 1762 active ACP members in the United States in 2003. A slightly modified questionnaire was also distributed to chairpersons of prosthodontic/restorative departments in the 54 U.S. dental schools. Data analysis was performed via frequency distribution and chi-square statistics., Results: Nine hundred and forty-five questionnaires were returned by members of the ACP (54% return rate) and 42 questionnaires were returned by the U.S. dental schools (78% return rate). The majority of the reporting prosthodontists (88%) and dental schools (98%) use a border-molded custom tray for final impressions for complete denture prosthodontics. The most popular material for border molding was plastic modeling compound (67% of reporting ACP members, and 95% of the responding dental schools). Variability of the materials used for final impressions was observed, with the most popular materials being polyvinylsiloxane for the ACP members (36%) and polysulfide for the dental schools (64%). Statistically significant differences were found in the materials used for border molding by prosthodontists based on the time elapsed since completion of prosthodontic training. No differences were found in the materials used for impression of edentulous arches based on years of experience. Geographic location did not influence the materials and methods used by prosthodontists for complete denture final impressions., Conclusions: There was variability of the materials and techniques used for final impressions by ACP members and dental schools; however, overall there was an agreement on the materials and techniques used by prosthodontists and dental schools. Distinct trends for increasing use of polyvinylsiloxane and polyether for border molding procedures and impressions of edentulous arches were observed both in members of the ACP and in the U.S. dental schools.

This review summarizes the highlights in the study of adult and pediatric asthma from October 2002 through October 2003. It is easiest to categorize this year's advances into physiologic, epidemiologic, therapeutic, and primarily pediatric developments. In physiology the identification of the ADAM33 gene as an asthma susceptibility gene has led to a new hypothesis concerning the pathogenesis of asthma. Understanding the integration of the upper and lower airways is likely to have important implications for patient management. Epidemiologic studies continue to show that asthma is a significant and costly disease, with medications comprising the most significant direct costs. Early intervention and improved management can significantly reduce the burden of illness. Research presented indicates there is an opportunity for allergist-immunologists to improve diagnostic and therapeutic approaches to asthma management. Our community has a strong commitment to health care quality, education, and delivery. The Journal will reflect this commitment with a new section devoted to these issues.

The authors conducted a retrospective database study of patients with asthma (age range, 6-55 yr) who initiated fluticasone propionate or montelukast sodium treatment between an index period of July 1998 and June 1999. All patients were observed for 12 months before and after the index period. Changes in asthma-related hospitalizations, emergency department visits, oral corticosteroid use, and short-acting beta-agonist use were analyzed. The odds of postindex asthma-related events were estimated. In multivariate analysis, use of a short-acting beta agonist (SABA) was significantly associated with fluticasone treatment (odds ratio [OR], 1.65; 95% confidence interval [CI], 1.21-2.26) and preindex use of SABAs (OR, 1.84; 95% CI, 1.34-2.53). In this managed care population, fluticasone and montelukast provided similar effectiveness.

Objective: To assess asthma control and patient satisfaction among pediatric users of montelukast in a clinical practice setting., Study Design: A prospective study of 175 children with persistent asthma, 6 to 14 years of age, who initiated treatment with montelukast between Feb-1998 and Aug-1998, in primary care and pediatric offices across the United States. Data on asthma control and satisfaction with treatment was collected in physicians' offices after enrollment and by survey to the patients' homes at 1 month of treatment., Results: Across the study population, improvements in mean scores for asthma control and parent satisfaction were observed at the 1-month follow-up compared with baseline. At 1 month, 57.7% of patients had none offour issues indicative of poor asthma control, compared with 19.4% at baseline. Similarly, after 1 month of treatment with montelukast, 2.7 times as many parents reported being very satisfied with asthma therapy (using montelukast) compared with the previous controller therapy regimen at baseline. During the 1-month follow-up period, montelukast was used as the only controller medication by 18.3% of patients, and in combination with another controller medication by 81.7%., Conclusions: Observations from this study over one month suggest that a significant percentage of pediatric patients successfully managed their asthma with montelukast and their parents were satisfied with their medication, compared to baseline.

Study Objective: To compare asthma-related health care expenditures among patients newly prescribed fluticasone propionate 44 or 110 microg, montelukast 5 or 10 mg, or zafirlukast 20 mg., Design: Retrospective cohort analysis of medical and pharmacy claims., Setting: University-affiliated health outcomes research center., Patients: Seven hundred eighty-one patients (aged > or = 4 yrs) with asthma treated with controller therapy for 9 months (postindex period), with no claim for an inhaled corticosteroid or leukotriene modifier in the previous 9 months (preindex period)., Intervention: Asthma-related medical and pharmacy data from insurance claims of four managed care plans (two Northeastern, one Midwestern, and one Western) were tabulated over the pre- and postindex periods., Measurements and Main Results: Numbers of patients identified were 284 beginning fluticasone propionate; 302, montelukast; and 195, zafirlukast. Fluticasone propionate treatment was associated with significantly (p<0.001) lower risk-adjusted asthma-related charges compared with montelukast and zafirlukast treatment: $528, $967, and $1359, respectively In this cohort, fluticasone propionate also was associated with fewer hospitalizations, less need for additional controller agents, and longer maintenance on the index drug compared with montelukast and zafirlukast., Conclusions: Based on these real-world data, as well as established national and international asthma guidelines, consideration should be given to inhaled corticosteroid therapy, particularly fluticasone propionate, for first-line, long-term effective management of asthma.

Objective: To review the literature examining the clinical use of leukotriene receptor antagonists in the treatment of allergic rhinitis., Data Sources: Biomedical literature accessed through MEDLINE (1990-November 2000) and Current Contents (week 35 of 1999 to week 48 of 2000). Key terms included leukotriene antagonists, montelukast, zafirlukast, and rhinitis (allergic)., Data Synthesis: Preliminary evidence on the clinical use of either montelukast or zafirlukast as monotherapy is equivocal, with one study noting benefit and another noting lack of benefit in symptom amelioration. A third study suggests that these agents may have a role in further modifying allergic rhinitis symptoms when used in combination with standard treatments., Conclusions: Future large-scale studies should assess the efficacy of these agents in the treatment of allergic rhinitis, in particular, to identify subsets of patients likely to derive the most benefit. Available data suggest it is reasonable and safe to add these agents to standard therapy if symptomatology remains unresolved.