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Marine aerosols play a critical role in impacting our climate by seeding clouds over the oceans. Despite decades of research, key questions remain regarding how ocean biological activity changes the composition and cloud-forming ability of marine aerosols. This uncertainty largely stems from an inability to independently determine the cloud-forming potential of primary versus secondary marine aerosols in complex marine environments. Here, we present results from a unique 6-day mesocosm experiment where we isolated and studied the cloud-forming potential of primary and secondary marine aerosols over the course of a phytoplankton bloom. The results from this controlled laboratory approach can finally explain the long-observed changes in the hygroscopic properties of marine aerosols observed in previous field studies. We find that secondary marine aerosols, consisting of sulfate, ammonium, and organic species, correlate with phytoplankton biomass (i.e., chlorophyll-a concentrations), whereas primary sea spray aerosol does not. Importantly, the measured CCN activity (κapp = 0.59 ± 0.04) of the resulting secondary marine aerosol matches the values observed in previous field studies, suggesting secondary marine aerosols play the dominant role in affecting marine cloud properties. Given these findings, future studies must address the physical, chemical, and biological factors controlling the emissions of volatile organic compounds that form secondary marine aerosol, with the goal of improving model predictions of ocean biology on atmospheric chemistry, clouds, and climate., Biological activity in the oceans produces volatile gases that undergo atmospheric oxidation to form secondary marine aerosol. These particles have profound impacts on cloud formation and climate.

Sea spray aerosols (SSAs) affect the Earth’s climate directly by scattering solar radiation and indirectly by acting as ice and cloud condensation nuclei. The relative magnitude of these effects remains uncertain, in part, from substantial compositional and morphological variability between individual particles. Here, the evolving heterogeneity within populations of primary SSAs produced from wave breaking of natural seawater within a wave flume is investigated. Over the course of the study, two successive phytoplankton blooms were induced in the seawater. The morphology, organic volume fraction, hygroscopicity, phase state, and surface tension of individual SSAs collected via deposition on a substrate were characterized using atomic force microscopy. Particles between ca. 0.3 and 1 μm in volume equivalent diameter displayed a distinctive morphology revealing an inorganic core coated with an organic shell. The inferred organic volume fraction was the largest at the peak of the first bloom. The corresponding shell thicknesses ranged from 21 to 40 nm at 20% relative humidity (RH). The organic shell phase state of the majority of the particles during both blooms was semisolid at 20% and 60% RH. At 20% RH, a minor fraction of the organic shells behaved as a solid, while at 60% RH some behaved as liquids during the first bloom. Similar results were evident at 20% RH for the second bloom but with no observed liquid particles at 60% RH. The thick, semisolid organic coatings could potentially reduce atmospheric water and gas uptake efficiencies onto SSAs at lower RH, along with the potential for ice nucleating activity. However, at 80% RH, the SSAs deliquesced and exhibited liquid-like behavior with surface tension values measured over individual particles of 41–87 mN m–1, demonstrating high particle-to-particle variability. The suppressed surface tension at 80% RH relative to pure water is attributed to the high concentrations of surface-active organic compounds, potentially further limiting the diffusion rate of gas molecules through the interface.

Mutations in Fused in Sarcoma (FUS) are present in familial and sporadic cases of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). FUS is localised in the nucleus where it has important functions in DNA repair. However, in ALS/FTD, mutant FUS mislocalises from the nucleus to the cytoplasm where it forms inclusions, a key pathological hallmark of neurodegeneration. Mutant FUS also inhibits protein import into the nucleus, resulting in defects in nucleocytoplasmic transport. Fragmentation of the neuronal Golgi apparatus, induction of endoplasmic reticulum (ER) stress, and inhibition of ER-Golgi trafficking are also associated with mutant FUS misfolding in ALS. Protein disulphide isomerase (PDI) is an ER chaperone previously shown to be protective against misfolding associated with mutant superoxide dismutase 1 (SOD1) and TAR DNA-binding protein-43 (TDP-43) in cellular and zebrafish models. However, a protective role against mutant FUS in ALS has not been previously described. In this study, we demonstrate that PDI is protective against mutant FUS. In neuronal cell line and primary cultures, PDI restores defects in nuclear import, prevents the formation of mutant FUS inclusions, inhibits Golgi fragmentation, ER stress, ER-Golgi transport defects, and apoptosis. These findings imply that PDI is a new therapeutic target in FUS-associated ALS.

Sea spray aerosol (SSA) can have complex carbon speciation that is affected by biological conditions in the seawater from which it originates. Biologically derived molecules can also interact with other longer-lived organic and inorganic carbon species in the sea surface microlayer and in the process of bubble bursting. An isolated wave channel facility was used to generate sea spray aerosol during a 1 month mesocosm study. Two consecutive phytoplankton blooms occurred, and sea spray aerosol was sampled throughout. Scanning transmission X-ray microscopy coupled with near-edge X-ray absorption fine structure spectroscopy (STXM-NEXAFS) was used to determine spatially resolved carbon speciation within individual particles from 0.18 to 3.2 μm. During phytoplankton blooms, coarse-mode particles exhibited an increased abundance of carboxylic acid-rich needlelike structures. The extent of organic enrichment in fine-mode particles correlates with the occurrence of aliphatic-rich organic species, as detected by an...

Ocean-derived microbes in sea spray aersosol (SSA) have the potential to influence climate and weather by acting as ice nucleating particles in clouds. Single particle mass spectrometers (SPMSs), which generate in situ single particle composition data, are excellent tools for characterizing aerosols under changing environmental conditions as they can provide high temporal resolution and require no sample preparation. While SPMSs have proven capable of detecting microbes, these instruments have never been utilized to definitively identify aerosolized microbes in ambient sea spray aersosol. In this study, an aerosol time-of-flight mass spectrometer was used to analyze laboratory generated SSA produced from natural seawater in a marine aerosol reference tank. We present the first description of a population of biological SSA mass spectra (BioSS), which closely match the ion signatures observed in previous terrestrial microbe studies. The fraction of BioSS dramatically increased in the largest supermicron particles, consistent with field and laboratory measurements of microbes ejected by bubble bursting, further supporting the assignment of BioSS mass spectra as microbes. Finally, as supported by analysis of inorganic ion signals, we propose that dry BioSS particles have heterogeneous structures, with microbes adhered to sodium chloride nodules surrounded by magnesium-enriched coatings. Consistent with this structure, chlorine-containing ion markers were ubiquitous in BioSS spectra and identified as possible tracers for distinguishing recently aerosolized marine from terrestrial microbes.

Knowledge of the surface composition of sea spray aerosols (SSA) is critical for understanding and predicting climate-relevant impacts. Offline microscopy and spectroscopy studies have shown that dry supermicron SSA tend to be spatially heterogeneous particles with sodium- and chloride-rich cores surrounded by organic enriched surface layers containing minor inorganic seawater components such as magnesium and calcium. At the same time, single-particle mass spectrometry reveals several different mass spectral ion patterns, suggesting that there may be a number of chemically distinct particle types. This study investigates factors controlling single particle mass spectra of nascent supermicron SSA. Depth profiling experiments conducted on SSA generated by a fritted bubbler and total ion intensity analysis of SSA generated by a marine aerosol reference tank were compared with observations of ambient SSA observed at two coastal locations. Analysis of SSA produced by utilizing controlled laboratory methods reveals that single-particle mass spectra with weak sodium ion signals can be produced by the desorption of the surface of typical dry SSA particles composed of salt cores and organic-rich coatings. Thus, this lab-based study for the first time unifies findings from offline and online measurements as well as lab and field studies of the SSA particle-mixing state.

The present research work emphasis on immobilization of lipase on PVA-alginate beads, which are used for biodiesel production via transesterification. The optimization of temperature, pH, and reusability of was performed on PVA-Alginate beads. The highest enzyme activity was found at a temperature of 40°C and pH 4.00. After six consecutive cycles of using the immobilized enzyme, the residual activity was 60% of the initial activity. The immobilized beads were stored at 4°C without buffer after 6 weeks, the immobilized enzyme retained 76.62% of initial activity.. The second-order mathematical model was developed using RSM. Transesterification process parameters were optimized by using ‘Full Factorial Design’ (FFD) with free lipase and immobilized lipase. The different factors considered for optimization were methanol/oil (M/O) ratio, reaction time, the weight of the catalyst with constant temperature and agitation speed. FFD was performed for free lipase, obtained the highest yield with optimum conditions; M/O ratio 9:1, reaction time 90 minutes, and weight of the catalyst was 0.3gm. Similarly, FFD was performed with immobilized lipase with the highest yield at 6:1 M/O ratio, 3 hours reaction time, the weight of the catalyst 3gm. FTIR was performed for the PVA-Alginate beads and lipase immobilized PVA-Alginate beads From FTIR spectra, the peaks shift from 1746 cm -1 to 1742 cm -1 signified the formation of biodiesel.

The experiment was conducted at the Seed Laboratory, Department of Agronomy, Bangladesh Agricultural University, Mymensingh during the period from September to October, 2011 to study the effect of chemical priming of seed on germination and growth of rice seedling cv. BRRI dhan 29. Seeds were soaked in 3% and 5% solutions of CaCl2, ZnSO4 and KCl for 24, 30, 36, 42, 48, 54, 60 hours, respectively. A control was maintained where seeds were subjected to no priming treatment. The experiment was laid out in a Completely Randomized Design with three replications. Primed seeds were tested for germination and vigour on sandy soil media (60:40) in petridish under field capacity. Seed quality tests included mean germination time, shoot length, shoot dry mass, root length and root dry mass. The results revealed that priming treatments had significant influence on germination and all the growth parameters of rice seedlings. Priming with 3% ZnSO4 for 30 hours showed the highest germination percentage and the lowest mean germinaion time. Priming with 5% KCl for 54 hours showed the highest root length while 5% of the same solution for 24 hours showed the highest root dry mass. On the contrary, seeds having no priming treatment showed the lowest values for germination, vigour index, shoot length,shoot dry mass, root length and root dry mass and the highest mean germination time. The present study concludes that rice seed cv. BRRI dhan29 could be primed with 3% ZnSO4 solution for 30 hours for improving germination and seedling growth.Bangladesh J. Agril. Res. 41(3): 451-460, September 2016

The extent to which water uptake influences the light scattering ability of marine sea spray aerosol (SSA) particles depends critically on SSA chemical composition. The organic fraction of SSA can increase during phytoplankton blooms, decreasing the salt content and therefore the hygroscopicity of the particles. In this study, subsaturated hygroscopic growth factors at 85 % relative humidity (GF(85 %)) of predominately submicron SSA particles were quantified during two induced phytoplankton blooms in marine aerosol reference tanks (MARTs). One MART was illuminated with fluorescent lights and the other was illuminated with sunlight, referred to as the "indoor" and "outdoor" MARTs, respectively. Optically weighted GF(85 %) values for SSA particles were derived from measurements of light scattering and particle size distributions. The mean optically weighted SSA diameters were 530 and 570 nm for the indoor and outdoor MARTs, respectively. The GF(85 %) measurements were made concurrently with online particle composition measurements, including bulk composition (using an Aerodyne high-resolution aerosol mass spectrometer) and single particle (using an aerosol time-of-flight mass spectrometer) measurement, and a variety of water-composition measurements. During both microcosm experiments, the observed optically weighted GF(85 %) values were depressed substantially relative to pure inorganic sea salt by 5 to 15 %. There was also a time lag between GF(85 %) depression and the peak chlorophyll a (Chl a) concentrations by either 1 (indoor MART) or 3-to-6 (outdoor MART) days. The fraction of organic matter in the SSA particles generally increased after the Chl a peaked, also with a time lag, and ranged from about 0.25 to 0.5 by volume. The observed depression in the GF(85 %) values (relative to pure sea salt) is consistent with the large observed volume fractions of non-refractory organic matter (NR-OM) comprising the SSA. The GF(85 %) values exhibited a reasonable negative correlation with the SSA NR-OM volume fractions after the peak of the blooms (i.e., Chl a maxima); i.e., the GF(85 %) values generally decreased when the NR-OM volume fractions increased. The GF(85 %) vs. NR-OM volume fraction relationship was interpreted using the Zdanovskii–Stokes–Robinson (ZSR) mixing rule and used to estimate the GF(85 %) of the organic matter in the nascent SSA. The estimated pure NR-OM GF(85 %) values were 1.16 ± 0.09 and 1.23 ± 0.10 for the indoor and outdoor MARTS, respectively. These measurements demonstrate a clear relationship between SSA particle composition and the sensitivity of light scattering to variations in relative humidity. The implications of these observations to the direct climate effects of SSA particles are discussed.

The experiments were conducted at the Soil Science Field Laboratory of Bangladesh Agricultural University, Mymensingh during boro season of 2013 to evaluate the effect of deep placement of nitrogen (N) fertilizers on rice yield and N use efficiency under two different water regimes [continuous flooding (CF) and alternate wetting and drying (AWD)]. After deep placement of USG and NPK briquettes and each split application of PU, the water samples were collected for five consecutive days and analyzed for ammonium-Nitrogen (NH 4 -N) concentration. In both water regimes the floodwater NH 4 -N concentration gave highest value at the second day of PU application followed by gradual decrease with time and in continuous flooding condition the release of NH 4 -N was higher compared to AWD condition. Deep placement of N fertilizers also increased grain yield under AWD compared to CF condition and the maximum value was obtained in treatment T 5 [USG 78 kg N ha -1 + PM 3 t ha -1 ] statistically similar to T 3 [USG, 156 kg N ha -1 ]. Due to application USG and NPK briquettes, the N uptake and N use efficiency also gave higher values in AWD compared to CF condition. The results revealed that the deep placement of USG with poultry manure performed better in terms yield, N uptake and N use efficiency by BRRI dhan29 under AWD condition. So, the deep placement of USG under AWD condition could be recommended for higher production of boro rice. SAARC J. Agri., 13(2): 161-172 (2015)

The authors introduced waste plastic pyrolysis oil (WPPO) as an alternative fuel characterized in detail and compared with conventional diesel. High density polyethylene, HDPE, was pyrolyzed in a self-designed stainless steel laboratory reactor to produce useful fuel products. HDPE waste was completely pyrolyzed at 330–490°C for 2-3 hours to obtain solid residue, liquid fuel oil, and flammable gaseous hydrocarbon products. Comparison of the fuel properties to the petrodiesel fuel standards ASTM D 975 and EN 590 revealed that the synthetic product was within all specifications. Notably, the fuel properties included a kinematic viscosity (40°C) of 1.98 cSt, density of 0.75 gm/cc, sulphur content of 0.25 (wt%), and carbon residue of 0.5 (wt%), and high calorific value represented significant enhancements over those of conventional petroleum diesel fuel.

Sea spray aerosol (SSA) particles represent one of the most abundant surfaces available for heterogeneous reactions to occur upon and thus profoundly alter the composition of the troposphere. In an effort to better understand tropospheric heterogeneous reaction processes, fundamental laboratory studies must be able to accurately reproduce the chemical complexity of SSA. Here we describe a new approach that uses microbial processes to control the composition of seawater and SSA particle composition. By inducing a phytoplankton bloom, we are able to create dynamic ecosystem interactions between marine microorganisms, which serve to alter the organic mixtures present in seawater. Using this controlled approach, changes in seawater composition become reflected in the chemical composition of SSA particles 4 to 10 d after the peak in chlorophyll-a. This approach for producing and varying the chemical complexity of a dominant tropospheric aerosol provides the foundation for further investigations of the physical and chemical properties of realistic SSA particles under controlled conditions.

The oceans represent a significant global source of atmospheric aerosols. Sea spray aerosol (SSA) particles comprise sea salts and organic species in varying proportions. In addition to size, the overall composition of SSA particles determines how effectively they can form cloud droplets and ice crystals. Thus, understanding the factors controlling SSA composition is critical to predicting aerosol impacts on clouds and climate. It is often assumed that submicrometer SSAs are mainly formed by film drops produced from bursting bubble-cap films, which become enriched with hydrophobic organic species contained within the sea surface microlayer. In contrast, jet drops formed from the base of bursting bubbles are postulated to mainly produce larger supermicrometer particles from bulk seawater, which comprises largely salts and water-soluble organic species. However, here we demonstrate that jet drops produce up to 43% of total submicrometer SSA number concentrations, and that the fraction of SSA produced by jet drops can be modulated by marine biological activity. We show that the chemical composition, organic volume fraction, and ice nucleating ability of submicrometer particles from jet drops differ from those formed from film drops. Thus, the chemical composition of a substantial fraction of submicrometer particles will not be controlled by the composition of the sea surface microlayer, a major assumption in previous studies. This finding has significant ramifications for understanding the factors controlling the mixing state of submicrometer SSA particles and must be taken into consideration when predicting SSA impacts on clouds and climate.

© 2017 Elsevier Inc. The impact of sea spray aerosol (SSA) on climate depends on the size and chemical composition of individual particles that make up the total SSA ensemble. There remains a lack of understanding as to the composition of individual particles within the SSA ensemble and how it changes in response to dynamic ocean biology. Here, we characterize the classes of organic compounds as well as specific molecules within individual SSA particles. The diversity of molecules within the organic fraction was observed to vary between submicrometer- and supermicrometer-sized particles and included contributions from fatty acids, monosaccharides, polysaccharides, and siliceous material. Significant changes in this molecular diversity were observed to coincide with the rise and fall of phytoplankton and heterotrophic bacteria populations within the seawater. Furthermore, the water uptake of individual particles was affected, as learned from studying the hygroscopicity of model systems composed of representative mixtures of salts and organic compounds.

Introduction: Pneumonia is a frequent and serious human illness. In Bangladesh, Acute Lower Respiratory Infection (ALRI) is a major cause of death among young children. Childhood mortality can be reduced by 50% with detection and early treatment of illness with antibiotics and immunization. Zinc plays an important role in the optimal function of the immune system by reducing the risk, severity and duration of infectious diseases. Zinc supplementation improves health and cell mediated immunity. Objectives: This study is aimed at documenting effect of zinc supplementation in preschool children on reducing ALRI. Methods: This was a double blind random control trial interventional study among180 child, conducted at Comilla CMH, from January 2010 to December 2011. The children aged 6-60 months were selected randomly for comparison of effect of Zinc and Vitamin B-Complex on ALRI. Results: In the study population, male to female ratio was 1.05:1. Baseline average age was 32 months and weight for height was 92% Of NCHS mean. It was found that 89% children completed immunization as per EPI schedule, the rest 11% were partially immunized. Twenty nine percent children had family history of Atopy. This study showed 15 episodes of ALRI in Zinc group in the control B-Complex group (1.09episodes/child/year) during the six months follow-up. There was no association of ALRI with sex. The male female ratio in this respect was 1.07:1. In this study there was statistically significant and clinically important (67%) reduction of episodes of ALRI in oral Zinc supplement group. Conclusion: This finding strongly suggests that oral supplement of Zinc reduces episodes of ALRI in children. DOI: http://dx.doi.org/10.3329/jafmc.v9i1.18736 Journal of Armed Forces Medical College Bangladesh Vol.9(1) 2013: 84-89

Four highly cellulolytic actinomycetous isolates namely SG 1 , SG 2 , SG 3 and SS1 were isolated from soil samples and provisionally identified as Streptomyces almquistii, S. caeruleus , S. hirsutus and S. endus, respectively. All the isolates showed heavy growth and liquefaction at 50˚C and pH 6.5 in Winstead’s medium having 1.2% of CMC. The isolates were allowed to grow in Winstead’s medium having Asparagine as a nitrogen source with different carbon sources for the maximum production of cellulases. The extracellular protein of the culture supernatant ranged from 1.14 μg /ml (SG 1 ) to 879.39 μg /ml (SG 3 ). The reducing sugar level of the culture supernatant ranged from 0.76 μg /ml (SG 2 ) to 558.33 μg /ml (SG 1 ). The highest CMC-ase activity (1431.81U/ml) was found with the crude enzyme of the strain SG 3 . The highest FP-ase activity (1087.11 U/ml) and Avicelase activity (1287.87U/ml) were found with the crude enzyme of SS 1 . To detrermine the optimum nitrogen sources, the isolates were allowed to grow in Winstead’s medium having saw dust for SG 1 and SG 3 , dry leaf for SS 1 and SG 2 as a carbon source with different nitrogen sources for the maximum production of cellulases. The extracellular protein of the culture supernatant ranged from 35.50 μg /ml (SG 1 ) to 328.62 μg /ml (SS 1 ) and the reducing sugar level of the culture supernatant ranged from 3.79 μg /ml (SG 1 ) to 114.39 μg /ml (SG 3 ). However the highest CMC-ase activity (1353.78 U/ml), and FP-ase activity (215.90 U/ml) were found with the crude enzyme of the strain SG 2 and Avicelase activity (356.06U/ml) was found with the crude enzyme of the isolate SS1 DOI: http://dx.doi.org/10.3329/cujbs.v6i1-2.17241 The Chittagong Univ. J. B. Sci.,Vol. 6(1&2):159-173, 2011

The inclusion of organic compounds in freshly emitted sea spray aerosol (SSA) has been shown to be size-dependent, with an increasing organic fraction in smaller particles. Here we have used electrospray ionization-high resolution mass spectrometry in negative ion mode to identify organic compounds in nascent sea spray collected throughout a 25 day mesocosm experiment. Over 280 organic compounds from ten major homologous series were tentatively identified, including saturated (C8-C24) and unsaturated (C12-C22) fatty acids, fatty acid derivatives (including saturated oxo-fatty acids (C5-C18) and saturated hydroxy-fatty acids (C5-C18), organosulfates (C2-C7, C12-C17) and sulfonates (C16-C22). During the mesocosm, the distributions of molecules within some homologous series responded to variations among the levels of phytoplankton and bacteria in the seawater. The average molecular weight and carbon preference index of saturated fatty acids significantly decreased within fine SSA during the progression of the mesocosm, which was not observed in coarse SSA, sea-surface microlayer or in fresh seawater. This study helps to define the molecular composition of nascent SSA and biological processes in the ocean relate to SSA composition.

Sea spray aerosol (SSA) is a globally important source of particulate matter. A mesocosm study was performed to determine the relative enrichment of saccharides and inorganic ions in nascent fine (PM2.5) and coarse (PM10-2.5) SSA and the sea surface microlayer (SSML) relative to bulk seawater. Saccharides comprise a significant fraction of organic matter in fine and coarse SSA (11 and 27%, respectively). Relative to sodium, individual saccharides were enriched 14-1314-fold in fine SSA, 3-138-fold in coarse SSA, but only up to 1.0-16.2-fold in SSML. Enrichments in SSML were attributed to rising bubbles that scavenge surface-active species from seawater, while further enrichment in fine SSA likely derives from bubble films. Mean enrichment factors for major ions demonstrated significant enrichment in fine SSA for potassium (1.3), magnesium (1.4), and calcium (1.7), likely because of their interactions with organic matter. Consequently, fine SSA develops a salt profile significantly different from that of seawater. Maximal enrichments of saccharides and ions coincided with the second of two phytoplankton blooms, signifying the influence of ocean biology on selective mass transfer across the ocean-air interface.

The composition and surface properties of atmospheric aerosol particles largely control their impact on climate by affecting their ability to uptake water, react heterogeneously, and nucleate ice in clouds. However, in the vacuum of a conventional electron microscope, the native surface and internal structure often undergo physicochemical rearrangement resulting in surfaces that are quite different from their atmospheric configurations. Herein, we report the development of cryogenic transmission electron microscopy where laboratory generated sea spray aerosol particles are flash frozen in their native state with iterative and controlled thermal and/or pressure exposures and then probed by electron microscopy. This unique approach allows for the detection of not only mixed salts, but also soft materials including whole hydrated bacteria, diatoms, virus particles, marine vesicles, as well as gel networks within hydrated salt droplets—all of which will have distinct biological, chemical, and physical processes. We anticipate this method will open up a new avenue of analysis for aerosol particles, not only for ocean-derived aerosols, but for those produced from other sources where there is interest in the transfer of organic or biological species from the biosphere to the atmosphere., Trapping sea spray aerosols by vitrification and imaging by cryogenic transmission electron microscopy reveals their nascent structure and allows for the identification of a variety of complex biological particles.

Aerosol particles influence global climate by determining cloud droplet number concentrations, brightness, and lifetime. Primary aerosol particles, such as those produced from breaking waves in the ocean, display large particle–particle variability in chemical composition, morphology, and physical phase state, all of which affect the ability of individual particles to accommodate water and grow into cloud droplets. Despite such diversity in molecular composition, there is a paucity of methods available to assess how particle–particle variability in chemistry translates to corresponding differences in aerosol hygroscopicity. Here, an approach has been developed that allows for characterization of the distribution of aerosol hygroscopicity within a chemically complex population of atmospheric particles. This methodology, when applied to the interpretation of nascent sea spray aerosol, provides a quantitative framework for connecting results obtained using molecular mimics generated in the laboratory with chemically complex ambient aerosol. We show that nascent sea spray aerosol, generated in situ in the Atlantic Ocean, displays a broad distribution of particle hygroscopicities, indicative of a correspondingly broad distribution of particle chemical compositions. Molecular mimics of sea spray aerosol organic material were used in the laboratory to assess the volume fractions and molecular functionality required to suppress sea spray aerosol hygroscopicity to the extent indicated by field observations. We show that proper accounting for the distribution and diversity in particle hygroscopicity and composition are important to the assessment of particle impacts on clouds and global climate., Measurements of the distribution of aerosol particle hygroscopicity, under conditions relevant to cloud formation, reveal that sea spray particles exhibit wide chemical diversity at the single particle level with consequent effects on cloud formation.

Naltrindole (1) (NTI) is a highly potent and selective delta-opioid receptor antagonist. In an effort to understand the origin of the high potency, affinity, and selectivity of NTI, we have examined the conformational role of its indolic benzene moiety through the synthesis of related naltrexone derivatives 3-8, which contain the benzene moiety in different orientations and at different attachments in the molecule. One of these naltrexone derivatives, 5, whose 7-indanyl benzene moiety is orthogonal to ring C of the morphinan system, is a potent delta-opioid receptor antagonist in vitro and in vivo. Computer-assisted molecular overlay studies of the minimized structures (2-8) revealed the importance of the position of the benzene moiety for effective interaction with delta-opioid receptors. In compounds 2, 4, and 5, the aromatic ring falls in the same region of space as that of the indolic benzene moiety of NTI, and all of these ligands possessed significant activity at delta-opioid receptors. Analogues (3 and 6-8) which were shown to have relatively weak delta-opioid receptor antagonist potency have their aromatic groups located in a space that is different from that of the more potent analogues.

The interaction of [D-Pen2,D-Pen5]enkephalin (DPDPE) and [D-Ala2,Glu4]deltorphin with delta-opioid receptor subtypes was investigated. Pretreatment of mice with the delta 1-opioid receptor antagonist, [D-Ala2,Leu5,Cys6]enkephalin (DALCE), produced a virtually complete antagonism of the antinociceptive actions of DPDPE, but had no effect on those of [D-Ala2,Glu4]deltorphin. In DALCE pretreated mice (i.e., delta 1-opioid receptors blocked), DPDPE was able to significantly antagonize the antinociceptive effects of [D-Ala2,Glu4]deltorphin. Pretreatment of mice with the delta 2-opioid receptor antagonist, naltrindole-5'-isothiocyanate (5'-NTII) produced a virtually complete antagonism of the antinociceptive effects of [D-Ala2,Glu4]deltorphin, but had no effect on the antinociception produced by DPDPE. In 5'-NTII pretreated mice (i.e., delta 2-opioid receptors blocked), [D-Ala2,Glu4]deltorphin had no effect on the antinociception produced by DPDPE. These data suggest that [D-Ala2,Glu4]deltorphin is highly selective for the delta 2-opioid receptor in vivo, and that neither agonist nor antagonist actions can be demonstrated at delta 1-opioid receptors for this peptide. In contrast, under appropriate conditions, DPDPE can be shown to interact with both delta 1- and delta 2-opioid receptor subtypes; DPDPE may have limited efficacy (i.e., is a partial agonist) at the delta 2-opioid receptor.

Highly selective nonpeptide ligands with potent delta opioid receptor antagonist activity have been developed using the message-address concept. This approach envisaged the delta opioid receptor to contain two major recognition subsites; a message subsite which recognizes the pharmacophore, and an address subsite that is unique for the delta receptor type and confers selectivity. The message and address components of the delta-selective enkephalins were postulated to be Tyr1 and Phe4, respectively, with Gly2-Gly3 functioning as a spacer. The message component of the target compounds in this study was derived from naltrexone and related structures. An indole system was fused to the C ring of naltrexone as a mimic of the address component. The benzene moiety of indole was viewed as the delta address component, mimicking the phenyl group of Phe4, and the pyrrole portion was used as a rigid spacer. Members of the series (1-23) were evaluated for opioid antagonist activity on the guinea pig ileum (GPI) and mouse vas deferens (MVD) preparations. Naltrindole (NTI, 1) was the most potent member of the series, with Ke values of approximately 0.1 nM at delta receptors. The antagonism by NTI was approximately 220- and 350-fold greater at delta than at mu and kappa opioid receptors. The binding of NTI and selected members of the series to guinea pig brain membranes was qualitatively consistent with their pharmacologic antagonist activity profiles in the MVD and GPI, but the Ki values were not in the same rank order. The selectivity of NTI arises mainly as a consequence of increased affinity at delta receptors. Thus, the Ke and Ki values of NTI were 1/530 and 1/90 that of the delta antagonist enkephalin analogue, ICI 174864. In contrast to NTI, ICI174864 derives its selectivity through greatly decreased recognition at mu and kappa receptors. The implications of the high affinity and selectivity of NTI as a consequence of its conformational rigidity are discussed. It is suggested that any attempt to model a receptor-bound conformation of an opioid peptide should consider affinity and potency at multiple receptor sites rather than selectivity alone.

The enantioselective synthesis of drugs is of fundamental importance in the pharmaceutical industry. In this experiment, students synthesize either enantiomer of warfarin, a widely used anticoagulant, in a single step from inexpensive starting materials. Stereoselectivity is induced by a commercial organocatalyst, (R,R)- or (S,S)-1,2-diphenylethylenediamine. The environmentally friendly microscale reaction is performed at ambient temperature, and the product can be purified by recrystallization or column chromatography. Product characterization includes thin-layer chromatography, NMR spectroscopy, and polarimetry.

A series of amino acid conjugates (2-6) of naltrindole (1) were synthesized from 7'-carboxynaltrindole (7) in order to obtain delta antagonists that would have minimal access to the central nervous system (CNS) upon peripheral administration. All of the ligands (2-7) were tested in smooth muscle preparations and found to be potent and selective delta opioid antagonists. Receptor binding showed 2-7 to be highly delta-selective, with Ki ratios (mu/delta, kappa/delta) ranging from 127 to 38,000. Two of the more selective conjugates, the glycinate 2 and aspartate 3, were evaluated by the iv and icv routes in mice, and they afforded very high iv/icv dose ratios (112,766 and 46,667, respectively) consistent with poor CNS penetration. The in vivo testing revealed that 2 and 3 are delta 1-selective antagonists, in contrast to naltriben and related ligands which are delta 2-selective. The fact that the binding data are not consistent with the in vivo data suggests that the origin of the selectivity of naltrindole congeners may be related to selective access to tissue compartments in the CNS rather than to binding affinity differences between delta opioid receptor subtypes.

Naltrindole-5'-isothiocyanate (5'-NTII), a nonequilibrium delta opioid receptor antagonist, has been shown to antagonize differentially the antinociception induced by DSLET without affecting that induced by DPDPE. In the present study, we investigated whether or not 5'-NTII can differentially affect DSLET and DPDPE binding to receptor sites in striatal slices of mouse brain. We found that 5'-NTII only changed the binding characteristics of [3H]DSLET and not that of [3H]DPDPE. Saturation binding studies revealed that 5'-NTII treatment in vitro inhibited [3H]DSLET binding by decreasing the affinity but not the number of binding sites. This finding was supported by saturation studies with [3H]DSLET in striatal slices from mice that were pretreated with 5'-NTII (10 nmol, i.c.v. or 10 mg/kg, s.c.). Thus, the results suggest that 5'-NTII can antagonize differentially the binding to striatal slices of mice of [3H]DSLET but not that of [3H]DPDPE. The binding parameters also suggest that 5'-NTII may not antagonize [3H]DSLET binding by alkylating at the receptor recognition site because the number of binding sites did not decrease. 5'-NTII may bind to some other part of the membrane to indirectly desensitize the receptor to a low affinity form. Lastly, the differential alteration of binding sites between [3H]DSLET and [3H]DPDPE by 5'-NTII strongly support the postulated existence of delta opioid receptor subtypes.

A series of naltrindole-related ligands (4-10) with an N-methyl,N-phenethyl,N-cinnamyl, or an unsubstituted basic nitrogen were synthesized and tested for opioid agonist and antagonist activity in smooth muscle preparations and in mice. The nor compounds (4 and 6) and the phenethyl derivatives (5 and 8) displayed full agonist activity (IC50 = 85-179 nM) in the mouse vas deferens preparation (MVD) while the other members of the series exhibited partial agonist or weak antagonist activity. In the guinea pig ileum preparation (GPI), all compounds except 8 were partial agonists. The ligands that were evaluated in mice were found to produce antinociception that was not selectively mediated via delta opioid receptors. However, two of these ligands (4 and 5) appeared to be delta-selective opioid receptor antagonists at subthreshold doses for antinociception. The finding that all of the compounds bind selectively to delta opioid receptors in guinea pig brain membranes together with the in vitro pharmacology and in vivo antagonist studies suggests that the lack of delta agonist selectivity in vivo may be due to a number of factors, including a basic difference between the delta receptor system in the MVD and in the mouse brain. Further, it is suggested that the constellation of message and address components in the morphindole nucleus may tend to stabilize delta receptors in the brain in antagonist state.

The isothiocyanate group was attached to the 4'-, 5'-, 6'-, or 7'-position of naltrindole in an effort to determine the importance of the position of this electrophilic group on the selectivity for subtypes of delta opioid receptors. All of the ligands were delta-selective when tested against standard agonists in smooth muscle preparations. However, the rank-order delta antagonism of antinociception in mice did not parallel the in vitro pharmacologic data. The 5'-isothiocyanate 2 was the most potent and selective antagonist in vivo, causing a 52-fold increase of the ED50 for [D-Ser2,D-Leu5]enkephalin-Thr6 (DSLET) and no increase for [D-Pen2,D-Pen5]enkephalin (DPDPE). The effect of each of the ligands on the binding of [3H]DSLET and [3H]DPDPE to guinea pig brain membranes clearly differentiated between the binding sites that recognize these radioligands. These studies provide additional evidence for the presence of two subtypes of delta opioid receptors.

In guinea pig brain membranes 7-benzylidenenaltrexone (BNTX) possesses 100-fold greater affinity (Ki = 0.1 nM) for [3H]DPDPE [3H][D-Pen2,D-Pen5]enkephalin) binding sites (delta 1) relative to those of [3H]DSLET ([3H][D-Ser2,Leu5]enkephalin-Thr6) (delta 2). The ED50 dose ratio (tail flick) in mice for the antagonism of DPDPE-induced antinociception of BNTX (6.3 pmol i.c.v.) was 7.2, whereas for DSLET, morphine and U69593 it was not significantly different from unity. The fact that there was no correlation of the binding or in vivo data for BNTX with antagonist potency in smooth muscle preparations suggests that the in vitro pharmacologic activity is mediated by delta-opioid subtypes that are different from those in the brain.

The pharmacological profile of naltrindole (NTI) and three of its analogues, N-methyl-NTI (N-Me-NTI), oxymorphindole (OMI) and naltriben (NTB) were studied in antinociceptive assays. The compounds were found to have agonist activities that appear to be mediated mainly by kappa opioid receptors because norbinaltorphimine (nor-BNI), the selective kappa opioid receptor antagonist inhibited their effects significantly. All of the compounds, behaved as antagonists at doses that were lower than those that produced agonist effects and they possessed a profile that was very selective for inhibiting the antinociceptive activities of delta opioid receptor agonists. Differential antagonism by NTB of the activities of DSLET and DPDPE was demonstrated.

Here we report on the design and synthesis of the first nonpeptide, nonequilibrium δ opioid receptor antagonist, naltrindole 5'-isothiocyanate (1, NTII), that exhibits high pharmacologic selectivity both in vitro and in vivo

The study was aimed at standardization of cryopreservation protocol for the common carp, ( Cyprinus carpio ) spermatozoa for using in the artificial propagation. Three extenders (Alsever’s solution, egg-yolk citrate and 0.9% NaCl) were combined with three cryoprotectants (ethanol, methanol and DMSO). Two-step freezing protocol (5°C to -4°C at a rate of 4°C per minute then -4°C to -80°C at a rate of 10°C per minute and finally held for 10 min) was carried out in a computer-controlled freezer where 0.25 ml straws containing spermatozoa were stored in a liquid nitrogen container at -196°C. Alsever’s solution with ethanol, Alsever’s solution with methanol and egg yolk citrate with DMSO gave better motility (%) in both pre-freeze (93.33±1.05, 90±1.83 and 88.33±2.11, respectively) and post-thaw (80±4.28, 74.17±3.96 and 76.67±4.59, respectively) periods whereas, 10% cryoprotectant gave the best motility during post-thaw period. Considering both pre-freeze and post-thaw motilities of the common carp spermatozoa, 1:9 was the best ratio for the milt and cryodiluents. The egg yolk citrate with DMSO yielded the best fertilization (37.67±1.76%) and hatching (28.67±1.85%) compared to other combinations under study. Key words: Cyprinus carpio ; spermatozoa; cryopreservation; cryoprotectant; cryodiluent; fertility. DOI: 10.3329/ujzru.v28i0.5287 Univ. j. zool. Rajshahi Univ. Vol. 28, 2010 pp. 51-55