bluuebunny/crossref_metadata_2025 huggingface dataset:
Some neurological and psychiatric complications in the disorders of the hypothalamus and the pituitary gland
Authors: Aszalós Zsuzsa
Published: April 2007

A központi idegrendszer és az endokrin rendszer kapcsolata rendkívül összetett. Az autonóm működéseket a hypothalamus neuronális és hormonális úton integrálja, biztosítja a szervezet homeosztázisát, koordinálja növekedési és szaporodási funkcióit, a stresszreakciókat, az élettani folyamatok ritmicitását, periodicitását és időzítését. Az általa termelt hormonok közül az antidiuretikus hormonnak a jól ismert hatásain túl szerepe van a szociális viselkedésben, mivel a vazopresszin-1A receptoron keresztül fokozza az agressziót. Az oxitocin az anyai viselkedés kialakítása mellett más szociális interakciókban, a párkapcsolati kötődésben, valamint az analgesiában és a fájdalom modulálásában játszik szerepet. A corticotrop-releasing hormon neurotranszmitterként is működik, kitüntetett szerepe van a stresszviselkedésben, szorongásban és depresszióban, erősen gátolja a mély alvást. Az evészavarok kialakulásában a hypothalamus neurotranszmitterei és neuropeptidjei közül a szerotoninnak, noradrenalinnak, GABA-nak, kolecisztokininnek, neuropeptid Y-nak, Agouti-related proteinnek, α-melanocyta-stimuláló hormonnak és ghrelinnek van alapvető jelentősége, a leptin- és galaninszintek határozzák meg, hogy anabolikus vagy katabolikus neurotranszmitterek képződjenek. A hőszabályozásban a centrális termoreceptorok játszanak szerepet, a cirkadián ritmusért a nucleus suprachiasmaticus főként „időzítő géneken” keresztül felelős. A hypothalamicus kórképek leggyakrabban bulimiához vagy anorexiához, hypersomniához, impotenciához, szorongásos attakokhoz vezetnek. Leggyakoribb térszűkítő folyamata a craniopharyngeoma. A vazopresszin-elválasztás hiánya vagy csökkenése diabetes insipidust, míg a túlzott mennyiségben képződő vazopresszin Schwartz–Barter-szindrómát okoz. A Fröhlich-, Kleine–Levin- és a Prader–Willi-szindróma jellegzetes neuropszichiátriai eltérésekkel jár. A hypophysis hipofunkció pszichiátriai képét a demencia-delírium kombináció jellemzi, a hypophysis-adenomák legjellegzetesebb neurológiai tünete a látótérkiesés. A somatotrop adenomák okozta tipikus neurológiai eltérések a carpal tunnel-szindróma, az obstruktív alvási apnoe és a fejfájás.
Telford's masonry bridges on the Carluke Road, Scotland
Authors: Day Tom
Published: April 2007

This paper describes the construction of Thomas Telford's imposing nineteenth century bridge at Cartland Crags in Lanarkshire, Scotland and five smaller masonry bridges on the same stretch of road leading to Carluke. It is based largely on letters written by Telford, his inspectors and the contractor—some in the form of progress reports and others describing incidents during construction. They provide a revealing insight into the interaction between the parties involved, particularly during the tendering process and when things went wrong on site.
Telford's Menai and Conwy suspension bridges, Wales
Authors: Day William
Published: April 2007

Menai and Conwy suspension bridges in Wales, both completed in 1826 to Telford's design, represented a significant advance in engineering science and were the culmination of extensive experiment and theoretical study. Telford established practices and procedures during the design and construction of the 177 m span Menai and 100 m span Conwy bridges for experiment, analysis, test and inspection that are recognised to this day as good practice in engineering. The ideas and methods adopted have had a lasting influence upon the profession.
Thomas Telford: highway engineer ahead of his time
Authors: Davies Hugh
Published: April 2007

Many of Thomas Telford's innovations in highway engineering were way ahead of his time, but are now familiar practice on modern motorways, ranging from using experiments to provide a rational basis for design to constructing massive cuttings, embankments and bridgeworks. The present paper describes the state of Britain's roads in the eighteenth century—when it took 230 h to travel between London and Edinburgh—and then discusses Telford's road-building activities and his novel approach to design. The disagreement with John McAdam is also described, together with an assessment of Telford's contribution to the evolution of modern highway engineering.
Telford's Highland roads—a new way of life for Scotland
Authors: Christopher R.
Published: April 2007

Thomas Telford constructed nearly 1200 km of roads and over 1000 bridges in the Highlands of Scotland for the government in 1803–21. Their purpose was to alleviate the living conditions in the poverty-stricken country by providing immediate work and opening up communications. This paper describes how Telford designed and organised this massive project, including his introduction into Scotland of competitive tendering by private contractors, his standard specification for roads and bridges and the need for immediate maintenance.
Thomas Telford, project manager
Authors: Barnes Martin
Published: April 2007

This paper examines Thomas Telford's achievement as a project manager against modern criteria for that role. It shows that he was undoubtedly one of the best project managers of his time but appears to have confined his innovations to engineering design rather than attempting to change the way major projects were managed. He nevertheless inspired all who worked with him and proved that you do not need modern communications and management tools to be an outstanding project manager.
In vivo assessment of the capacity of androstenedione to masculinize female mosquitofish (Gambusia affinis) exposed through dietary and static renewal methods
Authors: Stanko Jason P. , Angus Robert A.
Published: April 2007

In this study, we investigated the capacity of androstenedione to masculinize female mosquitofish. Previous studies have identified androstenedione in the water and sediment of the Fenholloway River, a Florida, USA, coastal river that receives paper mill effluent and contains masculinized eastern mosquitofish (Gambusia holbrooki). Females of the closely related western mosquitofish, Gambusia affinis, were exposed to androstenedione through both dietary and static renewal treatments. Morphological masculinization of female mosquitofish is characterized by the development of a male secondary sexual trait: an elongated and modified anal fin (gonopodium). Dietary exposure to 0.7, 7, 70, and 700 μg of androstenedione per gram of food failed to induce gonopodial development at any concentration within the six-week exposure period. Static renewal treatments used androstenedione concentrations of 0.14, 1.4, 14, 140, and 350 nM. Significant anal fin ray elongation was observed in all but the lowest exposure group. Fish growth during the static renewal exposure experiment was negatively correlated with androstenedione concentration. No significant effects were observed for gonadosomatic index, vitellogenin expression, or ovarian area in fish exposed to androstenedione via either the dietary or static renewal methods. These results indicate that exposure to androstenedione via water can cause masculinization of adult female mosquitofish in a relatively short period of time and that acute dietary exposure to androstenedione at the concentrations used is not sufficient to induce masculinization.
Biological uptake of polychlorinated biphenyls byMacoma balthicafrom sediment amended with activated carbon
Authors: McLeod Pamela B. , van den Heuvel-Greve Martine J. , Luoma Samuel N. , Luthy Richard G.
Published: April 2007

This work characterizes the efficacy of activated carbon amendment in reducing polychlorinated biphenyl (PCB) bioavailability to clams (Macoma balthica) from field-contaminated sediment (Hunters Point Naval Shipyard, San Francisco Bay, CA, USA). Test methods were developed for the use of clams to investigate the effects of sediment amendment on biological uptake. Sediment was mixed with activated carbon for one month. Bioaccumulation tests (28 d) were employed to assess the relationships between carbon dose and carbon particle size on observed reductions in clam biological uptake of PCBs. Extraction and cleanup protocols were developed for the clam tissue. Efficacy of activated carbon treatment was found to increase with both increasing carbon dose and decreasing carbon particle size. Average reductions in bioaccumulation of 22, 64, and 84% relative to untreated Hunters Point sediment were observed for carbon amendments of 0.34, 1.7, and 3.4%, respectively. Average bioaccumulation reductions of 41, 73, and 89% were observed for amendments (dose = 1.7% dry wt) with carbon particles of 180 to 250, 75 to 180, and 25 to 75 μm, respectively, in diameter, indicating kinetic phenomena in these tests. Additionally, a biodynamic model quantifying clam PCB uptake from water and sediment as well as loss through elimination provided a good fit of experimental data. Model predictions suggest that the sediment ingestion route contributed 80 to 95% of the PCB burdens in the clams.
Biomonitoring of estrogenic exposure and identification of responsible compounds in bream from Dutch surface waters
Authors: Houtman Corine J. , Booij Petra , van der Valk Karin M. , van Bodegom Peter M. , van den Ende Frank , Gerritsen Anton A.M. , Lamoree Marja H. , Legler Juliette , Brouwer Abraham
Published: April 2007

The exposure to and effects of estrogenic compounds in male breams from Dutch freshwater locations were investigated. Ovotestis was observed infrequently (maximum frequency 16%). However, plasma vitellogenin (VTG) concentration was elevated highly at some locations. Estrogenic activities in male bream plasma, liver, and in gastrointestinal content were measured in the estrogen-responsive chemical-activated luciferase gene expression (ER-CALUX®) assay. Plasma concentrations of vitellogenin correlated very well with the estrogenic activities in gastrointestinal content. The ER-CALUX activity in gastrointestinal content thus could provide a biomarker for recent exposure to estrogenic compounds, and the gastrointestinal content was chosen as investigative matrix for the toxicity identification and evaluation ([TIE]; bioassay-directed fractionation) of estrogenic compounds in bream. The approach consisted of a reversed-phase high-performance liquid chromatography fractionation of gastrointestinal content extract, directed by ER-CALUX and followed by gas chromatography analysis. The estrogenic hormones 17β-estradiol and its metabolite estrone were identified as major contributors to the activity at all locations (except the reference location), independent of the presence or absence of a known source of estrogenic activity, such as a sewage treatment plant. Chemical screening showed the presence of other pollutants, such as a lower chlorinated dioxin and the disinfectants clorophene and triclosan. However, these compounds did not have high estrogenic potencies and their concentrations were not high enough to contribute significantly to the observed estrogenic activity.
Biodegradability relationships among propylene glycol substances in the organization for Economic Cooperation and Development ready- and seawater biodegradability tests
Authors: West Robert J. , Davis John W. , Pottenger Lynn H. , Banton Marcy I. , Graham Cynthia
Published: April 2007

Eight propylene glycol substances, ranging from 1,2-propanediol to a poly(propylene glycol) (PPG) having number-average molecular weight (Mn) of 2,700 (i.e., PPG 2700), were evaluated in the Organization for Economic Cooperation and Development (OECD) ready- and seawater biodegradability tests. Uniformity in test parameters, such as inoculum source/density and test substance concentrations, combined with frequent measurements of O2 consumption and CO2 evolution, revealed unexpected biodegradability trends across this family of substances. Biodegradability in both tests decreased with increased number of oxy-propylene repeating units (n = 1, 2, 3, 4) of the oligomeric propylene glycols (PGs). However, this trend was reversed for the PPG polymers, and increased biodegradability was observed with increases of average n to seven, 17, and 34 (Mn = 425, 1,000, and 2,000, respectively). This relationship between molecular weight and biodegradability was reversed again when average n was incremented from 34 (PPG 2000) to 46 (PPG 2700). Six of the tested substances (n = 1, 2, 3, 7, 17, and 34) met the OECD-specified criteria for “ready biodegradability,” whereas the tetrapropylene glycol (n = 4) and PPG 2700 substances failed to meet these criteria. Biodegradation half-lives for these eight substances ranged from 3.8 d (PPG 2000) to 33.2 d (PPG 2700) in the ready test, and from 13.6 (PG) to 410 d (PPG 2700) in seawater. Biodegradation half-lives in seawater were significantly correlated with half-lives determined in the ready test. However, half-lives in both tests were correlated poorly with molecular weight, water solubility, and log KOW. It is speculated that the molecular conformation of these substances, perhaps more so than these other physicochemical properties, has an important role in influencing biodegradability of the propylene glycol substances.
Histidine-rich glycoprotein from the hemolymph of the marine musselMytilus edulisL. binds Class A, Class B, and borderline metals
Authors: Devoid Samantha J. , Etter Ron , Sugumaran Manickam , Wallace Gordon T. , Robinson William E.
Published: April 2007

Few studies have directly addressed the question of how metals (both essential and nonessential) are transported in the circulatory system of bivalve mollusks. One potential metal-transport protein, histidine-rich glycoprotein (HRG), has previously been isolated and characterized from the blood plasma of the marine mussel Mytilus edulis L. The present study was undertaken to investigate the extent to which mussel HRG can bind a variety of essential and nonessential metals in vitro, using immobilized metal-ion affinity chromatography (IMAC) and sodium dodecyl sulfate–polyacrylamide gel electrophoresis. The equilibrium metal speciation model MINTEQA2 was used to compute the amount of metal that bound to the IMAC packing material during the charging and initial wash steps. Results demonstrated that HRG can bind all seven of the metals tested (Ca, Cd, Hg, Mg, Ni, Pd, and Zn) and that HRG is the only metal-binding protein in IMAC eluents. Because HRG-metal binding strengths (log Ka) likely correspond with histidine–metal binding strengths, and because HRG is the predominant mussel plasma protein, the majority of each of the seven metals probably would be present in mussel blood as protein-bound metal rather than as free metal ion. The finding that a single mussel plasma protein may be responsible for binding all these metals raises important questions about how these different metals are subsequently transferred from HRG to different tissues of the mussel, where they may exhibit tissue-specific patterns of utilization, sequestration, elimination, and toxicity.
Adult tree swallow(Tachycineta bicolor)survival on the polychlorinated biphenyl-contaminated Housatonic River, Massachusetts, USA
Authors: Custer Christine M. , Custer Thomas W. , Hines James E. , Nichols James D. , Dummer Paul M.
Published: April 2007

Tree swallows (Tachycineta bicolor) were captured and banded at six sites that differed in polychlorinated biphenyl (PCB) contamination levels in the Housatonic River watershed, western Massachusetts, USA, from 2000 through 2004 to test the prediction that apparent survival rates of females in more contaminated areas were lower than those from less contaminated areas. We also tested whether plumage coloration affected over-winter survival and whether concentrations of PCBs in eggs differed between birds that did and that did not return the following year. Apparent survival rates were calculated using mark—recapture methods and compared using Akaike's Information Criterion. Model-adjusted survival rates ranged from 0.365 to 0.467 for PCB-contaminated females and between 0.404 and 0.476 for reference females. Models with either survival or capture probability modeled as functions of treatment (degree of PCB contamination), year, and age received some support. The model-averaged parameter estimate reflecting a treatment effect for high-PCB birds was negative ( = −0.046, SE() = 0.0939). Fifty-four percent of the total model weights involved models in which survival was a function of PCB treatment. Eggs were collected for contaminant analyses from a random sample of females that did and that did not return the following year. Concentrations of total PCBs were the same or higher in the eggs of females that returned compared to the eggs of those that did not return at both the highly and the moderately contaminated PCB sites. This may have resulted from higher-quality females with higher lipid reserves being more likely than lower-quality females to return the following year. Percentage lipid was positively correlated with total PCBs in eggs. Survival rates were similar among swallows with brown versus blue plumage.
Microcystin accumulation in freshwater bivalves from Lake Taihu, China, and the potential risk to human consumption
Authors: Chen Jun , Xie Ping
Published: April 2007

The potential risk through ingestion of microcystins (MC) in contaminated mollusks has not been well studied. The present paper studied seasonal changes of MC content (determined by liquid chromatography—mass spectrometry) in various organs of three species of bivalves (Cristaria plicata, Hyriopsis cumingii, and Lamprotula leai) in Lake Taihu, China, where toxic cyanobacterial blooms occurred. Coinciding with peaks of seston MC (maximum, 5.7 μg/L) and MC in cyanobacterial blooms (maximum, 0.534 mg/g), most organs showed sharp MC peaks during the summer, indicating both fast uptake and fast depuration by bivalves. Because hepatopancreas and intestine had considerably higher MC content than other organs, they are the most dangerous for human consumption. Both the present and previous studies show that the hepatopancreatic MC and total tissue MC often are correlated in various aquatic invertebrates. During the peak of the cyanobacterial blooms, C. plicata had higher hepatopancreatic MC content than the other bivalves, whereas H. cumingii had higher intestinal MC content than the other bivalves. Estimated daily intakes for humans from the consumption of whole tissues of the three bivalves were 0.48 to 0.94 μg MC-LR equivalent/kg body weight (12- to 23.5-fold the tolerable daily intake value proposed by the World Health Organization), which indicates a high risk for humans consuming these bivalves.
Biokinetics and tolerance development of toxic metals inDaphnia magna
Authors: Tsui Martin Tsz-Ki , Wang Wen-Xiong
Published: April 2007

Daphnia magna is widespread in many freshwater systems of temperate regions and frequently is used to test metal toxicity. Recently, studies have been performed to determine metal biokinetics and development of tolerance in this important zooplankton species. In the present paper, we review the recent progress in these areas and suggest possible directions for future studies. Substantial differences exist in aqueous uptake, dietary assimilation, and elimination of several metals (Cd, Se, Zn, Ag, Hg, and MeHg) by D. magna. The routes of uptake are metal-specific, with Se and MeHg being accumulated predominantly through diet. All metals except Ag can be biomagnified from algae to D. magna, providing that metal concentrations in algae and algal food density are relatively low. Methylmercury is biomagnified in all situations. As a route for metal elimination in D. magna, maternal transfer is especially important for Se, Zn, and MeHg. On the other hand, the effect of single-generation exposure to metals on D. magna is very different from multigeneration exposure, which often results in a significantly higher metal tolerance. Moreover, D. magna easily loses metal tolerance developed through long-term exposure. Recovery from metal stress can temporarily increase the sensitivity of D. magna to metal toxicity. Finally, metallothionein-like protein is responsible for minimizing metal toxicity in D. magna. The results inferred from these studies can be extrapolated to other aquatic invertebrates as well as to other pollutants in the aquatic environment.
Relation of diclofop-methyl toxicity and degradation in algae cultures
Authors: Cai Xiyun , Liu Weiping , Jin Meiqing , Lin Kunde
Published: April 2007

Information on the effects of pesticide degradation on aquatic organisms is needed to properly evaluate the ecotoxicity arising from the use of pesticides and for aquatic risk assessment. This work evaluated the toxicity of diclofop-methyl (DM) and its two major metabolites, diclofop (DC) and 4-(2,4-dichlorophenoxy)-phenol (DP), to three freshwater microalgae, Chlorella pyrenoidosa, Chlorella vulgaris, and Scenedesmus obliquus. The degradation of DM in the algal suspensions was determined. Diclofop-methyl was rapidly absorbed into the cells of the tested algae, in which it was hydrolyzed to DC and further degraded to DP. The half-lives derived from the first-order kinetics indicated that DP (t1/2 = 2.47–5.80/d) degraded faster than DC (t1/2 = 6.24–12.25/d). The 4-(2,4-dichlorophenoxy)-phenol was the strongest inhibitor of algal growth, followed by DM and DC, as indicated by their EC50 values of 0.17 to 0.25, 0.42 to 2.23, and 4.76 to 8.89 mg/L, respectively. The evaluation of overall DM toxicity to tested algae in the aquatic systems thus needs to take into consideration the degradation of DM. A positive relationship appears to exist between the toxicity of DM and DC and their degradability in algal suspensions. Such a relationship, if confirmed using more pesticides and aquatic organisms, would improve the quality and efficiency of the aquatic risk assessment and management associated with pesticide use.
Effects of salinity and hypoxia on cadmium bioaccumulation in the shrimp Palaemon longirostris
Authors: Pierron Fabien , Baudrimont Magalie , Boudou Alain , Massabuau Jean-Charles
Published: April 2007

The aim of the present study was to investigate the role of two key environmental factors of estuarine ecosystems, salinity and hypoxia, on the Cd bioaccumulation by direct exposure in the white shrimp Palaemon longirostris. Two types of experiments were performed in the laboratory. First, we studied Cd accumulation by shrimp after metal exposure at two salinities (0.2 and 10‰) and/or water oxygen levels (21 and 6 kPa). We also investigated the role of hypoxia in more detail and, in particular, its interaction with water Cd concentration by subjecting shrimp at low salinity (0.2‰) to two oxygen levels (21 and 6 kPa) and four concentrations of dissolved Cd metal (0.2, 0.5, 2, and 10 μg/L). Second, we studied the ventilatory and circulatory responses of P. longirostris to changes in oxygen and Cd concentrations to understand some basic aspects of the underlying mechanisms involved in the accumulation process. Our findings allow us to confirm that salinity is the main factor acting on dissolved Cd bioaccumulation processes. However, we demonstrate that hypoxia also must be classified as being of primary importance. Through its physiological effect on the prawn, hypoxia strongly enhances the rate of Cd accumulation in gills and hepatopancreas. Its magnitude is inversely related to the metal concentration, because its influence increases when the metal concentration is low. Our results show that chemical speciation is, indeed, the primary factor that influences metal contamination. On the other hand, at low salinity, under conditions in which metal bioavailability is increased, we show that ventilation modifies metal accumulation in the gills by a factor of two.
Out of the Closet? German Patriotism and Soccer Mania
Authors: Majer-O'Sickey Ingeborg
Published: April 2007

As host of the 2006 soccer World Cup in June and July 2006, Germany was suddenly full of different Germans, waving millions of black-red-gold mini flags and wearing their (and others') national colors with abandon. Was this show of nationalism a new kind of trans/national patriotism? Most certainly, the national enthusiasm exhibited in Germany had nothing whatsoever to do with past demonstrations of patriotism. With the focus on the country as host to world soccer aficionados, the world also learned of a multicultural Germany that has existed for the last fifty years or so. It learned that it is not always successful with its social and economic problems, and that the desire for national unity is sometimes difficult to fulfill. Quite correctly, the national media described Germany as joyous, generous, and open-minded hosts. In the foreign press, too, the old stereotypes were broken down.
Climate, Water, and Crises in the Southwest Asian Bronze Age
Authors: Thompson William R.
Published: April 2007

Evidence on river flow levels and other forms of climate indicators suggest significant variation in climate and water availability within the Bronze Age period. Intermittent deterioration in climate appears to have contributed to periodic crises (toward the ends of the fourth, third, and second millennia, as well as in the middle of the second millennium) manifested throughout the Near East. These periodic crises are associated variably with hinterland pressures on urban centers, governmental collapse, and, to a lesser extent, economic contraction. Climate was probably not the primary driver of these times of troubles, but climatic deterioration systematically made things worse.
Design of a near‐optimal adaptive filter in digital signal processor for active noise control
Authors: Yang S. M. , Lee K. F. , Tsai S. E.
Published: April 2007

Adaptive filter has been applied in adaptive feedback and feedforward control systems, where the filter dimension is often determined by trial‐and‐error. The controller design based on a near‐optimal adaptive filter in digital signal processor (DSP) is developed in this paper for real‐time applications. The design integrates the adaptive filter and the experimental design such that their advantages in stability and robustness can be combined. The near‐optimal set of controller parameters, including the sampling rate, the dimension of system identification model, the dimension (order) of adaptive controller in the form of an FIR filter, and the convergence rate of adaptation is shown to achieve the best possible system performance. In addition, the sensitivity of each design parameter can be determined by analysis of means and analysis of variance. Effectiveness of the adaptive controller on a DSP is validated by an active noise control experiment. Copyright © 2007 John Wiley & Sons, Ltd.
Polyterthiophenes as Donors for Polymer Solar Cells
Authors: Koppe M. , Scharber M. , Brabec C. , Duffy W. , Heeney M. , McCulloch I.
Published: April 2007

Thiophene‐containing polymers blended with fullerenes have recently demonstrated impressively high photovoltaic efficiencies. One drawback of this class of polymers is their relatively low ionization potential, which leads to rather low open‐circuit voltages. Polyterthiophenes belong to a material class that has recently captured a large amount of interest for polymer electronic applications because of its excellent transport properties. Because of the slightly lower ionization potential, this material class appears more attractive for photovoltaic applications than polythiophenes. In this work, the photovoltaic performance of bulk heterojunction solar cells from polyterthiophene/fullerene composites is discussed and compared to the polymer/fullerene blend morphology.
Triphenylphosphine‐Catalyzed Dehydrogenative Coupling Reaction of Carboxylic Acids with Silanes – A Convenient Method for the Preparation of Silyl Esters
Authors: Liu Guo‐Bin , Zhao Hong‐Yun , Thiemann Thies
Published: April 2007

Triphenylphosphine has been found to be an efficient catalyst for the dehydrosilylation of carboxylic acids with silanes. In the presence of 4 mol % of triphenylphosphine (PPh3), dehydrosilylation reactions in DMF afforded the corresponding silyl esters at 120 °C in good yield.
New Highly Effective Phosphite‐Phosphoramidite Ligands for Palladium‐Catalysed Asymmetric Allylic Alkylation Reactions
Authors: Pàmies Oscar , Diéguez Montserrat , Claver Carmen
Published: April 2007

We have designed a new family of readily available highly‐modular phosphite‐phosphoramidite ligands for asymmetric allylic alkylation reactions. The introduction of a phosphoramidite moiety in the ligand design is highly advantageous in the product outcome. Thus, this ligand series affords high reaction rates and enantioselectivities and, at the same time, shows a broad scope for disubstituted hindered and unhindered substrate types.
Lung function and respiratory symptoms in subjects with asbestos‐related disorders: A cross‐sectional study
Authors: Hilt Bjørn , Lien Jan T. , Lund‐Larsen Per G.
Published: April 2007

The prevalence of respiratory symptoms and lung function impairment was studied in a sample of men from a population screening of asbestos‐related disorders. When the rates were adjusted for age and smoking habits, 83 subjects with lung fibrosis had an increased prevalence of respiratory symptoms, in particular, phlegm when coughing and breathlessness grades 1–3. Among 200 subjects under 70 years of age who had pleural plaques only, a statistically significant increase was observed in the prevalence of breathlessness grade 1 compared to an external reference population. Among 98 asbestos‐exposed subjects who had normal chest X‐rays, there was an increase in the prevalence of breathlessness grade 2, cough during the day, and phlegm when coughing. There was a higher proportion of subjects with lung fibrosis who were below 80% of the predicted values for forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV1) than in the other groups. There was also a higher proportion of subjects with pleural plaques only who were below 90% of the predicted value for FVC than in a group of 90 subjects without asbestos exposure. In accordance with previous studies, these results indicate that pleural plaques in asbestos workers may be of greater importance as a clinical feature than has been recognized in the past.
Respiratory dysfunction after potroom asthma
Authors: Wergeland Ebba , Lund Eiliv , Waage Jan E.
Published: April 2007

Thirty‐five men developed bronchial asthma while working in the potrooms in a primary aluminum production plant. Their asthma was diagnosed as work‐related (“potroom asthma”). When examined 1–43 months after cessation of exposure (average follow‐up period 2.5 yr), the group had an increased relative risk of morning cough (RR 1.7 CL95% 0.6–5.1), dyspnea on exertion (RR 2.8 CL95% 0.9–8.4), and wheezing (RR 6.1 CL95% 2.3–16.3) compared to controls from the same plant, in a 1:2 matched analysis. Matching criteria were age, smoking habits, and time of employment in the plant. The group means for FEV1 and MMEF were lower than for the controls, but the differences were not statistically significant. Ten of the 35 reported persisting asthma, dyspnea at night, or dyspnea on exertion. The study indicates an increased risk of respiratory dysfunction after potroom asthma. Medical folllow‐up after cessation of exposure is recommended.
Pilot study on health effects of environmental 2,3,7,8‐tcdd in missouri
Authors: Webb Karen , Evans R. Gregory , Stehr Paul , Ayres Stephen M.
Published: April 2007

Waste oil contaminated with 2,3,7,8‐TCDD was sprayed at various sites in the state of Missouri. Eighty‐two individuals who reported living or working in TCDD‐contaminated areas and 40 individuals with little or no exposure to TCDD were selected for study; 85% elected to participate in the study. Data were obtained from medical histories, general physicals, neurological and dermatological examinations, and laboratory tests. There were no cases of chloracne reported. The only hematologic comparison that was significant was a higher mean platelet count in the exposed group. This study did not produce any firm indication of increased disease prevalence related to environmental TCDD exposures. Since this was a pilot study, it is important that we continue to limit human exposure to dioxin to the lowest levels technologically feasible until definitive answers to the health consequences of exposure are determined.
A respiratory epidemiological survey of workers in a small South African foundry
Authors: Myers J. E. , Garisch D. , Myers H. S. , Cornell J. E.
Published: April 2007

A cross‐sectional study to assess prevalence of respiratory abnormality was conducted among 107 South African foundry workers. The prevalence of pneumoconiosis was 10.3% overall, increasing to 38% for workers with more than 15 years of service. Dyspnea was present in 38% of workers, chronic simple bronchitis in 15.9%, and asthmatic symptoms in 27%. Pneumoconiosis was not associated with higher prevalence rates of other respiratory abnormalities. The high overall prevalence of respiratory symptoms might be explained by exposure to environmental pollutants other than dust.
Delivery outcome among women employed in the plastics industry in Sweden and Norway
Authors: Ahlborg Gunnar , Bjerkedal Tor , Egenaes John
Published: April 2007

In Sweden and Norway separate case‐control studies of pregnancy outcome for the period 1973–1981 among female workers in the plastics industry were carried out with similar design. Employment records were obtained from companies producing and/or processing plastics and these were matched with the national medical birth and malformation registers. Within the cohorts of pregnancies during which the mother held employment in a plastics industry (1.397 in the Swedish and 288 in the Norwegian study), cases of stillbirths or infant deaths, selected malformations, or low birthweight (< 2,000 g) were identified. For each case two controls from the same source were individually matched with regard to date of birth, age of mother, and parity. Exposure data concerning the 44 Swedish and ten Norwegian triplets were obtained from the employers. An increased odds ratio was found for processing of polyvinylchloride (PVC) plastics (95% CI Sweden 1.0–5.1; total material 1.1–4.5). However, processing of cold plastics yielded a higher odds ratio than processing of heated plastics. No increased odds ratio was found for processing of styrene or polyurethane plastics. Since not all of the plastics industries in the two countries participated in the studies and the number of cases was small, the result must be interpreted with caution.
Occupational exposure to benzene in the shoe industry
Authors: Karačić Višnja , Skender Ljiljana , Prpić‐Majić Danica
Published: April 2007

In order to determine the possible actual exposure to benzene in the shoe industry from industrially used solvents, glues, and paints containing benzene as a nondeclared constituent, phenol in urine and benzene in blood, as indices of internal exposure to benzene, were measured in workers (N = 33). Since toluene, in contrast to benzene, is declared as a constituent in several glues, toluene in the blood of workers was also analysed. All analyses were performed using gas chromatography. Urine samples were collected on Monday morning (MI) before work and on Wednesday (WI) before and (WII) after work. Venous blood samples were taken on Wednesday only, 1/2 hour after work. There was no difference in the phenol concentrations of MI and WI, while the phenol concentration of WII was about twice as high as that in WI. In all blood samples, benzene was found, as well as toluene, which was about four times higher in comparison with benzene. A correlation (r = 0.465; p < .01) was found between the difference in preand postshift phenol concentrations (WII — WI) in urine and the benzene concentrations in blood. The results presented show that a trace amount of benzene, which is often not declared as a constitutent in industrially used chemicals, could be a source of marked exposure to benzene. It can also be concluded that changes in phenol in urine (if preshift and postshift samples are taken) might be a sufficiently sensitive parameter to assess exposure to benzene even when other data concerning the presence of benzene in the working atmosphere are not available.
Sister chromatid exchanges and DNA repair capability in sanitary workers exposed to ethylene oxide: Evaluation of the dose‐effect relationship
Authors: Sarto Franco , Clonfero Erminio , Bartolucci Giovanni B. , Franceschi Claudio , Chiricolo Mariella , Levis Angelo G.
Published: April 2007

Determination of ethylene oxide (EtO) in the working environment and induction of sister chromatid exchanges (SCE) and unscheduled DNA synthesis (UDS) in peripheral lymphocytes of 10 exposed sanitary workers and 10 control subjects matched for sex, age, and smoking habits are reported. The relationship between the external dose of EtO and the frequency of SCE was determined in the above group and in a group of 41 sanitary workers previously studied. The 10 newly examined workers were exposed to EtO concentrations (1.84 ppm as time‐weighted average) intermediate between the high (10.7 ppm) and low (0.35 ppm) levels of exposure of the two previously examined groups (19 and 22 workers, respectively). A statistically significant (p < 0.002) increase of SCE frequency was observed between the present control and exposed groups. The inducibility of unscheduled DNA synthesis by gamma rays was lower in the lymphocytes of the exposed workers than in controls, but the difference was not statistically significant. A significant relationship between the frequency of SCE and the level of EtO exposure for the three exposed groups was demonstrated by two different statistical methods. It is suggested that the present Italian threshold limit value for EtO (3 ppm) may not protect the exposed workers against possible genotoxic effects and that even a chronic exposure to 1 ppm may not be devoid of genotoxic risk.
Evaluation of epidemiologic approaches to the study of lung disease related to cotton dust exposures
Authors: Wegman David H.
Published: April 2007

Epidemiologic approaches to improved understanding of the several reactions observed in cotton processors began in 1955 with Schilling's symptom classification of Monday‐morning chest tightness. To date, epidemiologic studies have identified the importance of increasing years of exposure to the development of both specific and nonspecific chronic respiratory symptoms and of acute change in pulmonary function. The few longitudinal studies suggest similar associations with accelerated loss of pulmonary function. Respirable dust level has been associated, cross‐sectionally, with symptoms and with acute function change, but studies have not yet been made with sufficient prospective collection of both exposure and health effects data to estimate accurately the association of continued exposure with accelerated loss of lung function or development of disability. Furthermore, there has been very limited field study comparing exposure to respirable dust distinguished from exposure to endotoxin. With careful attention to features of study design and analytic plans, investigators can take advantage of simple technology to examine the fate of the acute responder, the potential for recovery if exposure is reduced or ceased, and the long‐term dose response relationship between different cumulative measures of exposure and chronic disease.
Methods to assess airborne concentrations of cotton dust
Authors: Corn Morton
Published: April 2007

Assessment of concentrations of airborne cotton dust in the factory is necessary to determine adherence to applicable Permissible Exposure Limits (PELs) on a day‐to‐day basis, as well as for investigatory studies of an epidemiological nature. The latter are required on an ongoing basis to determine the adequacy of PELs to prevent disease in the exposed population. A strategy of sampling includes considerations of the numbers of samples to be obtained for statistical validity and the locations of samples. Current practice is to obtain more “personal samples” of exposure wherever possible, but with regard to cotton dust, instrumentation is not available for such sampling. In the U.S., the vertical elutriator is the instrument of choice for determining the concentrations of cotton dust in air. Results are expressed as milligrams of airborne particulate (cotton dust) per cubic meter.
The role of endotoxin for reactions after exposure to cotton dust
Authors: Rylander Ragnar
Published: April 2007

Gram‐negative bacteria and their endotoxins are present on all parts of the cotton plant and occur in large numbers after rain or frost. Endotoxins activate pulmonary macrophages that in turn recruit neutrophils into the airways. Platelets accumulate in pulmonary capillaries. The presence of these cells allows for the initiation of acute and chronic inflammation. Dose‐response relationships have been demonstrated between endotoxin and fever, chest tightness, and reduction in air flow (bronchoconstriction) in cotton workers. Limited data suggest that after cotton dust exposure, other symptoms, such as airway hyperreactivity and chronic inflammation, are also related to the endotoxin exposure. Tentative thresholds for airborne endotoxins are presented.
Current trends in research on the etiology and pathogenesis of byssinosis
Authors: Holt Patrick G.
Published: April 2007

The features of the cotton dust syndrome which need to be considered when formulating a hypothesis on mechanism(s) are: 1) the presence of fever, 2) the “Monday effect,” 3) the slow onset of forced expiratory volume in 1 second (FEV1) changes, and 4) the presence of bronchitis in chronic sufferers but the absence of emphysema or fibrosis. The main hypotheses concerning the mechanisms are direct release of histamine triggered by cotton dust components, immune reactions (principally antibody mediated) to cotton dust antigens, and inflammatory response(s) triggered by endotoxins released from bacterial contaminants on the dust.

While histamine release and immune reactions may occur as a result of cotton dust inhalation, it is suggested that they are of secondary importance in comparison to inflammation. Evidence is reviewed that implicates bacterial lipopolysaccharide (LPS) present in the dust as the principal etiologic agent in this process. It is postulated that LPS inhalation stimulates a secretory response by lung macrophages, involving the release of effector molecules which trigger coagulation, bronchoconstriction, fever, and mucus production. LPS‐induced macrophage secretory products also promote the local sequestration and activation of both neutrophils and platelets, which serve to amplify the inflammatory response. Evidence is presented implicating both interstitial and alveolar macrophages in this process.

The problems associated with the identification of “high risk” groups of cotton workers will be discussed, from a number of viewpoints; consideration will be given to the role of a variety of environmental factors (including tobacco smoking) in this context, as well as possible genetic factors. Regarding genetic predisposition, preliminary evidence will be presented from ongoing studies on the presence of high and low responders to LPS.
Preliminary approach to the diagnosis of byssinosis
Authors: Dehong Li , Shixuan Lu , Maobo Ding , Cuijuan Zhang
Published: April 2007

The prevalence of byssinois was studied in two cotton mills by a standardized questionnaire and pulmonary function measurements (forced expiratory volume in 1 second; FEV1). In mill A, the dust level was high (57‐159 mg/m3). Among 90 participants, 80 were interviewed twice at an interval of 4 months, and disagreement on actual presence or absence of byssinosis was 7.5 percent. Twenty out of ninety workers had complaints of Monday symptoms and the prevalence was 22.2 percent. In mill B, the dust control (6.8 mg/m3) was relatively good. Among 173 participants from the carding room, two had complaints of Monday symptoms and the prevalence was 1.2 percent. A significant correlation was found between duration of employment and prevalence of byssinosis in mill A. FEV1 was measured in 9 byssinotics, 29 nonbyssinotics, and 30 controls before and after work on Mondays and Wednesdays. A significant decrease of 177 ml on average (7.8%) was found in byssinotics after work on Monday, whereas in nonbyssinotics, the decrease of FEV1 was nonsignificant. In controls, a slight increase in FEV1 after work was observed.
Some opinions on byssinosis in China
Authors: Guo‐chang Xing
Published: April 2007

On the basis of some study results in China and reports from abroad, a conclusion should be drawn that leads to the recognition of a pneumoconiosis‐like lesion of interstitial fibrosis. This disease is called “cotton pneumoconiosis” and we may classify these occupational lesions into four types: 1) byssinosis; 2) chronic obstructive pulmonary disease (COPD); 3) cotton fever; and 4) cotton pneumoconiosis. Byssinosis, COPD, cotton fever and cotton pneumoconiosis may be different types of responses due to the different duration of exposure, the different parts of bronchial tree (upper respiratory tract, small airway, and respiratory part) where deposition occurs, and the different components of cotton dust (broken cotton fibers, bracts, pericarps, bacteria, and fungi). These responses, which include histaminelike reaction, allergy, and stimulation of foreign material, happen in different symptoms of the syndrome among cotton mill workers. But no matter whether responses caused by inhalation of dust are inflammation or allergic reaction, cotton dust is foreign stimulation on deposited sites, causing lung fibrosis after lung stimulation. For the health of cotton workers, we must pay attention not only to the acute effects but also to the chronic lesions. We therefore suggest that these four types of occupational lung disorders caused by inhalation of cotton dust may be called by the joint name, “Byssinosis syndrome”.
A study of byssinosis in Hong Kong and Jakarta: Research methods and objectives
Authors: Lam Tai Hing , Ong Say Gark , Baratawidjaja Karnen Garna
Published: April 2007

Two research projects to study the prevalence of byssinosis in Hong Kong and Jakarta were conducted. Both projects had similar objectives and design. Although the studies were conducted within the agreed upon guidelines, it became obvious that there were differences in the methods of implementation due to the researchers' attempts to overcome local obstacles. Many factors were found to influence the implementation of a research proposal: local culture and customs, business practices, factory management, availability of local information, and the prevalence of the disease being studied. Provided that these factors are understood and taken into account, the comparability of results should not be substantially affected.
Byssinosis and other respiratory problems in the cotton industry of Hong Kong
Authors: Ong Say Gark , Lam Tai Hing , Wong C. M. , Chow W. K. , Ma P. L. , Lam Shi Kai , O'Kelly F. J.
Published: April 2007

Between February 1982 and October 1984, a total of 2,317 workers from all levels of cotton processing—carding, blowing, spinning and weaving—were studied in a citywide cross‐sectional survey. The workers were administered the British MRC Questionnaire in local dialect and their pre‐ and postshift lung functions were assessed by portable spirometers. The prevalence of byssinosis for the whole industry was 2.3%, being much greater in the more dusty processes (blowing and carding, 5.6%; weaving 1.6%). Even more important was the prevalence of chronic obstructive airways disease (COAD) (13.8%) and a combination of nonspecific respiratory symptoms (10.0%), characterized by chest tightness and dyspnea, but not related to any specific day of the week such as those seen in typical byssinosis. The importance of these two large groups of respiratory problems in relation to byssinosis and the pathogenesis of respiratory diseases in people exposed to cotton dust is discussed.