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PubMed1996

Mu- and delta-opioid receptor antagonists precipitate similar withdrawal phenomena in butorphanol and morphine dependence.

The relative involvement of mu- and delta-opioid receptors in the mediation of butorphanol-, as compared to morphine-, dependence was examined with the use of highly selective antagonists at mu- and delta-opioid receptors. Extracellular fluid levels of glutamate (Glu) and aspartate (Asp) were measured within the pontine locus coeruleus following precipitation of withdrawal from dependence on either butorphanol or morphine in conscious Sprague-Dawley rats. Dependence was induced by intracerebroventricular (i.c.v.) infusion of butorphanol (26 nmol/mu l/h), morphine (26 nmol/mu l/h) or saline vehicle (1 mu l/h) for 3 days by means of an osmotic minipump. Microdialysis probes (2 mm tip) were inserted into the locus coeruleus 24 h before precipitation of withdrawal by i.c.v. injection of either the mu-opioid receptor antagonist, D-Pen-Cys-Tyr-D-Trp-Orn-Thr-Pen-Thr-NH2 (CTOP; 48 nmol/5 mu l or 48 nmol/5 mu l), or the delta-opioid receptor antagonist, naltrindole (17-cyclopropy;methyl-6,7-dehydro-4,5-epoxy-3, 14-dihydroxy-6,7,2'3'-indolmorphinan hydrochloride; 48 nmol/5 mu l or 100 nmol/5 mu l). Baseline levels of Glu ranged from 9.59 + or - 1.27 to 12.84 + or - 3.01 mu M in the various treatment groups. Levels of Asp were similar. Precipitation of withdrawal by CTOP elicited significant increases of Glu and Asp in both morphine- and butorphanol-dependent rats. Maximal increases in Glu of 425% and 258% above baseline levels were elicited in the first 15 min microdialysis sample following i.c.v. injection of CTOP in morphine- and butorphanol-dependent rats, respectively. Behavioral signs of withdrawal were greater in morphine than butorphanol-dependent groups. The i.c.v. treatment with naltrindole elicited increases in Glu and Asp that were similar, although less marked, than those precipitated by CTOP treatment. Administration of naltrindole produced equivalent signs of withdrawal in both morphine- and butorphanol-dependent rats. Withdrawal from dependence on both morphine and butorphanol is characterized by elevations in coerulear levels of excitatory amino acids. Responses elicited following the use of selective mu- and delta-opioid receptor antagonists to precipitate withdrawal suggest that the role played by these receptors in mediation of the signs and symptoms of withdrawal do not differ greatly between butorphanol- and morphine-dependent rats.

Animals↗

PubMed2003

Sediment flux to the sea as influenced by changing human activities and precipitation: example of the Yellow River, China.

Since the 1970s, the sediment flux of the Yellow River to the sea has shown a marked tendency to decrease, which is unfavorable for wetland protection and oil extraction in the Yellow River delta. Thus, an effort has been made to elucidate the relation between the sediment flux to the sea and the drainage basin factors including climate and human activities. The results show that the sediment flux to the sea responds to the changed precipitation in different ways for different runoff and sediment source areas in the drainage basin. If other factors are assumed to be constant, when the annual precipitation in the area between Longmen and Sanmenxia decreases by 10 mm, the sediment flux to the sea will decrease by 27.5 million t/yr; when the precipitation in the area between Hekouzhen and Longmen decreases by 10 mm, the sediment flux to the sea will decrease by 14.3 million t/yr; when the precipitation in the area above Lanzhou decreases by 10 mm, the sediment flux to the sea will decrease by 17.4 million t/yr. A multiple regression equation has been established between the sediment flux to the sea and the influencing factors, such as the area of land terracing and tree and grass planting, the area of the land created by the sediment trapped by check dams, the annual precipitation, and the annual quantity of water diversion by man. The equation may be used to estimate the change in the sediment flux to the sea when the influencing variables are further changed, to provide useful knowledge for the environmental planning of the Yellow River drainage basin and its delta.

Agriculture↗

PubMed1994

Precipitations of thyrotropin receptor-related peptides by immunoglobulin G of patients with Hashimoto's thyroiditis.

In order to study whether specific binding sites for Hashimoto's IgG exist in TSH receptor, we have examined the TSH receptor binding activity of IgG of patients with Hashimoto's thyroiditis using synthetic peptides corresponding to the amino acid sequences in the extracellular domain of human TSH receptor. Eight different peptides were synthesized, radiolabeled and examined by immunoprecipitation assay. Among the peptides studied, peptide (352-378) was significantly precipitated by IgG of patients with Hashimoto's thyroiditis compared with control subjects. Ten out of twenty patients with Hashimoto's thyroiditis showed more precipitations of peptide (352-378) than mean + 2SD of those of control subjects. Peptide (352-378) was precipitated by IgG in a dose dependent manner and the binding of peptide (352-378) to IgG was displaced by the addition of increased amount of cold peptide (352-378). Precipitations of peptide (352-378) positively correlates with both TGHA and MCHA titers. Two out of fourteen patients with Graves' disease, one out of seven patients with subacute thyroiditis and none of eleven patients with thyroid tumor showed more precipitations of peptide (352-378) than mean + 2SD of those of control subjects. These results suggest that one of binding sites for Hashimoto's IgG is present in the amino acid sequence of 352-378 in the extracellular domain of TSH receptor.

Amino Acid Sequence↗

PubMed1995

Distribution of calcium pyroantimonate precipitates in Xenotoca Mauthner cells at normal and increased functional activity.

The pyroantimonate method was used for the ultrastructural localization of calcium ions (Ca2+) in Xenotoca Mauthner cells under normal conditions and after prolonged natural stimulation. In normal state, the highest concentration of these ions was observed as compact electron-dense precipitates inside the synaptic cleft exactly at the synaptic active zones. Some amount of dotted precipitates was revealed in the synaptic boutons. In the extracellular space and in the cytoplasm the precipitates are seen mainly as single membrane-bound dots. After prolonged stimulation significant redistribution of the precipitates was observed. They were entirely absent in the presynaptic areas, became diffuse and discontinuous or disappeared completely at the synaptic active zones. On the contrary, in the cytoplasmic organelles (subsynaptic cisternae, vacuoles, smooth reticulum, mitochondria) the precipitates were aggregated into continuous dense clusters inside the membranous compartments or on their surfaces. Also, large amounts of granules, not associated with membranes, were localized inside the cytoplasm directly at the cytoskeletal elements. It is suggested that membrane subsynaptic organelles are the primary structures which sequestrate, accumulate and retain Ca2+. Thus, these elements, together with deeper elements of smooth cytoplasmic reticulum, may control the cytoplasmic activity of Ca2+ and, as a consequence, control many physiologically significant reactions of the neurons.

Animals↗

PubMed2005

Improved daily precipitation nitrate and ammonium concentration models for the Chesapeake Bay Watershed.

Daily precipitation nitrate and ammonium concentration models were developed for the Chesapeake Bay Watershed (USA) using a linear least-squares regression approach and precipitation chemistry data from 29 National Atmospheric Deposition Program/National Trends Network (NADP/NTN) sites. Only weekly samples that comprised a single precipitation event were used in model development. The most significant variables in both ammonium and nitrate models included: precipitation volume, the number of days since the last event, a measure of seasonality, latitude, and the proportion of land within 8km covered by forest or devoted to industry and transportation. Additional variables included in the nitrate model were the proportion of land within 0.8km covered by water and/or forest. Local and regional ammonia and nitrogen oxide emissions were not as well correlated as land cover. Modeled concentrations compared very well with event chemistry data collected at six NADP/AirMoN sites within the Chesapeake Bay Watershed. Wet deposition estimates were also consistent with observed deposition at selected sites. Accurately describing the spatial distribution of precipitation volume throughout the watershed is important in providing critical estimates of wet-fall deposition of ammonium and nitrate.

Air Pollutants↗

PubMed2006

Comparison between electrocoagulation and chemical precipitation for metals removal from acidic soil leachate.

This paper provides a quantitative comparison between electrocoagulation and chemical precipitation based on heavy metals (Cd, Cr, Cu, Ni, Pb and Zn) removal from acidic soil leachate (ASL) at the laboratory pilot scale. Chemical precipitation was evaluated using either calcium hydroxide or sodium hydroxide, whereas electrocoagulation was evaluated via an electrolytic cell using mild steel electrodes. Chemical precipitation was as effective as electrocoagulation in removing metals from ASL having low contamination levels (30 mg Pbl(-1) and 18 mg Znl(-1)). For ASL enriched with different metals (each concentration of metals was initially adjusted to 100 mg l(-1)), the residual Cr, Cu, Pb and Zn concentrations at the end of the experiments were below the acceptable level recommended for discharge in sewage urban works (more than 99.8% of metal was removed) using either electrocoagulation or chemical precipitation. Cd was more effectively removed by electrochemical treatment, whereas Ni was easily removed by chemical treatment. The cost for energy, chemicals and disposal of metallic residue of electrocoagulation process ranged from USD 8.83 to 13.95 tds(-1), which was up to five times lower than that recorded using chemical precipitation. Highly effective electrocoagulation was observed as the ASL was specifically enriched with high concentration of Pb (250-2000 mg Pbl(-1)). More than 99.5% of Pb was removed regardless of the initial Pb concentration imposed in ASL and, in all cases, the residual Pb concentrations (0.0-1.44 mg l(-1)) were below the limiting value (2.0 mg l(-1)) for effluent discharge in sewage works.

Electrochemistry↗

PubMed2003

Use of co-immunoelectrodiffusion to detect presumed disease-associated precipitating antibodies, and time-course value of specific isotypes in bird-breeder's disease.

BACKGROUND AND OBJECTIVE: The practical value of immunological diagnosis of bird-breeder's disease (BBD) is controversial, because of difficulties in distinguishing active disease patients from simple contact subjects. The aim of this study was to determine the diagnostic and prognostic value of (a) presumed disease-associated antibodies precipitating pigeon antigens (immunoglobulin A (IgAp) and P2 component), (b) characterization of specific isotypes (IgG, IgM, and IgA), and (c) antibody kinetics after antigen eradication. METHODS: 405 subjects (775 sera) in contact with birds were studied [by means of co-immunoelectrodiffusion (Co-IED) and enzyme-linked immunofiltration (ELIFA)] with soluble extracts of pigeon droppings and squab crop milk. These patients were divided into two groups based on the final clinical evaluation of the patients' physicians, which was taken as the gold standard (positive in 90 and negative in 315 cases). RESULTS: On the basis of this gold standard, the detection of presumed disease-associated precipitating antibodies by Co-IED had a specificity of 95.5%, a sensitivity of 98.7%, an accuracy of 98%, and positive and negative predictive values of 95.5% and 98.7%, respectively. Most of the patients with a final positive diagnosis of BBD had specific IgG, IgM, and IgA antibodies by ELIFA. After antigen eradication, anti IgAp and/or P2 antibodies disappeared more rapidly than other precipitating systems. CONCLUSION: Identification by Co-IED of precipitating immune complexes IgAp and/or P2 significantly reinforces the intrinsic credibility of immunological diagnosis of BBD. Compared to these presumed disease-associated precipitating antibodies, detection and time course of specific IgM, IgA antibodies, provided no additional diagnostic value or prognostic arguments to judge disease activity after antigen eradication.

Aged↗

PubMedDate not supplied

Precipitating factors for the chronic fatigue syndrome.

The etiology of the Chronic Fatigue Syndrome (CFS) is unknown but it is usually considered to be postinfectious or postviral. Many infecting agents have been suspected as causative but none has been proven. We investigated precipitating factors in 134 CFS patients through the use of a questionnaire, interview, clinical examination and serology for infecting agents; 35 healthy controls completed a similar questionnaire. CFS started with an apparently infectious illness in 96 (72%) but a definite infection was only found in seven of these 96 (7%). Thirty-eight (28%) had no apparent infectious onset: 15/38 (40%) had noninfectious precipitants (trauma, allergy, surgery). There was no apparent precipitating event in 23/38 (61%). Immunization was not a significant precipitant. Stressful events were very common in the year preceding the onset of CFS (114/134, 85%) but these occurred in only 2/35 (6%) of the controls (p < .0001). The onset of CFS may be associated with preceding stressful events and multiple other precipitants. An infectious illness is not uniformly present at the onset and no single infectious agent has been found; CFS is most likely multifactorial in origin.

Adult↗

PubMed1997

Role of noradrenergic functions in the modification of naloxone-precipitated withdrawal jumping in morphine-dependent mice by diabetes.

The role of noradrenergic functions in the modulation of naloxone-precipitated withdrawal jumping in morphine-dependent mice by diabetes were examined. Both diabetic and non-diabetic mice were chronically treated with morphine (8 - 45 mg/kg, s.c.) for 5 days. During this treatment, neither diabetic nor non-diabetic mice showed any signs of toxicity. After morphine treatment, withdrawal was precipitated by injection of naloxone (0.3 mg/kg, s.c.). The number of naloxone-precipitated withdrawal jumps within 5 min after injection of naloxone was significantly less in morphine-dependent diabetic mice than in morphine-dependent non-diabetic mice. However, there was no significant difference in the number of naloxone-precipitated withdrawal jumps from 5 to 15 min after injection of naloxone between diabetic and non-diabetic mice. The turnover rate of noradrenaline in the frontal cortex in morphine-dependent non-diabetic mice, but not in morphine-dependent diabetic mice, was significantly increased 5 min after administration of naloxone. These results suggest that the functional changes in central noradrenergic systems may be involved in the reduction of naloxone-precipitated jumping in morphine-dependent diabetic mice.

Analgesics, Opioid↗

PubMed2001

Precipitation signal in pollen rain from tropical forests, South India.

We have analyzed the pollen content of 51 surface soil samples collected in tropical evergreen and deciduous forests from the Western Ghats of South India sampled along a west to east gradient of decreasing rainfall (between 11 degrees 30-13 degrees 20'N and 75 degrees 30-76 degrees 30'E). Values of mean annual precipitation (Pann, mm/yr) have been calculated at each of the 51 sampling sites from a great number of meteorological stations in South India, using a method of data interpolation based on artificial neural network. Interpolated values at the pollen sites of Pann range from 1200 to 5555mm/yr, while mean temperature of the coldest month (MTCO) remains >15 degrees C and humidity factor (AET/PET, the actual evapotranspiration to potential evapotranspiration ratio) remains also included between 65 and 72%.Results are presented in the form of percentage pollen diagrams where samples are arranged according to increasing values of annual precipitation. They indicate that the climatic signal of rainfall is clearly evidenced by distinct pollen associations. Numerical analyses show that annual precipitation is an important parameter explaining the modern distribution of pollen taxa in this region. Pollen taxa markers of high rainfall (Pann >2500mm/yr) are Mallotus type, Elaeocarpus, Syzygium type, Olea dioica, Gnetum ula, and Hopea type, associated with Ixora type and Caryota. Pollen taxa markers of low rainfall (Pann <2500mm/yr) are Melastomataceae/Combretaceae, Maytenus type, Lagerstroemia and Grewia. The proportions of evergreen taxa and of arboreal taxa vary according to rainfall values. Indeed, when rainfall is <2500mm/yr, percentage of arboreal pollen (AP) is <50% and proportion of evergreen taxa is <20%. When rainfall exceeds 2500mm/yr, AP values average 70%, and proportion of evergreen taxa increases from 60 to 90%. Moreover, a good correlation between precipitation and proportion of evergreen taxa (0.85) presumes that precipitation can be estimated from pollen data.

Journal Article↗

PubMed2001

Determination of nitroarenes in precipitation collected in Kanazawa, Japan.

Eight nitroarenes, 1,3-, 1,6- and 1,8-dinitropyrenes, 1-, 2- and 4-nitropyrenes, 6-nitrochrysene and 2-nitrofluoranthene, in precipitation collected in Kanazawa were determined. The nitroarenes in the precipitation were concentrated onto solid phase extraction cartridges, and identified with high-performance liquid chromatography with chemiluminescence detection. The nitroarene concentrations in the precipitation were in the range 0.016-15 pmol/L, and the nitroarene composition tended to be the same as that in airborne particulates. 1-Nitropyrene in river water and seawater were also determined. 1-nitropyrene concentrations on the days after rain (19-110 fmol/L) were higher than those on the days before rain (4,11 fmol/L). Moreover, 1-nitropyrene concentrations in the river water were much lower than those in the precipitation, but were higher than those in the seawater. These results suggested that the nitroarenes in the precipitation and the river water came from airborne particulates.

Air Pollutants↗

PubMed2000

Polycyclic aromatic hydrocarbons in the bulk precipitation and surface waters of Northern Greece.

Bulk (wet and dry) precipitation and surface water sampling was undertaken in the main plain of central Macedonia in Northern Greece. Fourteen polycyclic aromatic hydrocarbons (PAHs) included in the US EPA's priority pollutant list were analysed. The concentrations determined in bulk precipitation were in general within the range of values worldwide reported. Concentrations were highest in the cold months. Deposition fluxes of PAHs were of the same order of magnitude as reported data. The greatest values were found when high concentrations of PAHs in precipitation coincided with large precipitation amounts. The concentrations of PAHs in surface waters (main rivers, tributaries, ditches, etc) were in general lower than those in bulk precipitation, and among the lowest reported for European rivers, excepting Np and Ph. Bulk deposition and domestic effluents are suggested as being the main PAH sources into surface waters.

Cold Temperature↗

PubMed2001

Experimental study of precipitating systems; computerised analysis of the optical transmittance and associated noise.

The change of the transmittance in a precipitant system has been measured by using a focused laser beam into a precipitation cell in which the precipitate was generated by an injection technique. We have monitored the evolution of the transmittance on several precipitation processes with different chemicals (PbI2, PbSO4, BaSO4 and BaC2O4) and quantities of precipitated mass (20.0, 17.5, 15.0, 12.5 and 10.0 mg). The noise associated to the transmittance signal has been obtained by a numerical procedure based on computer analysis, finding that it provides information about particle shape features and nucleation kinetics.

Journal Article↗

PubMedDate not supplied

Isolation of a beta 2-glycoprotein from human serum after precipitation with dextran sulfate and manganese chloride.

A new procedure was developed which affords isolation from among the euglobulins of human serum a beta 2-glycoprotein with a high degree of immunological and electrophoretic homogeneity. The isolated protein displays specific binding affinity for the activated form of the C4 component (C4b), and was identified by immunological and physico-chemical criteria as the C4 binding protein. The isolation procedure comprises the following steps: precipitation of euglobulins from serum at pH 5.5 and low ionic strength; precipitation of beta-lipoproteins from the redissolved precipitate with dextran sulfate and CaCl2; precipitation of a fraction of the lipoprotein-free euglobulins with dextran sulfate and MnCl2; redissolution of the precipitate and eventually chromatography on Sepharose 4B. The overall yield was between 15 and 20 per cent. The final product, devoid of immunologically detectable protein contaminants, was a homogeneous proline-rich monomeric beta 2-glycoprotein made up of eight disulfide-bonded polypeptide chains of the same molecular weight 63,000 +/- 3,000. Under non-reducing conditions, the molecular weight of both the native and the SDS-treated protein was 490,000 +/- 25,000. A monospecific antiserum to the isolated protein was raised in rabbits and used for the quantitation of the protein in sera of normal fasting donors; a mean concentration of 25 mg per 100 ml of serum (1 SD: 5) was established.

Chlorides↗

PubMed2001

Nanometer-scale solute segregation at heterophase interfaces and microstructural evolution of molybdenum nitride precipitates.

The interrelationship between coherency and solute segregation at metal/metal-nitride heterophase interfaces is studied on a subnanometer scale by both atom-probe field-ion and electron microscopies for molybdenum nitride precipitates in Fe-2 at% Mo-X, where X = 0.4 at% Sb or 0.5 at% Sn. Internal nitridation at 550 degrees C generates thin platelet-shaped molybdenum nitride precipitates, while nitridation at 600 degrees C produces, in addition to the small-scale structure with precipitates of the thin-platelet type, a much coarser structure of thick plates and spheroidal precipitates. The solute species Sn and Sb segregate at the heterophase interfaces of the coarse precipitates and Gibbsian interfacial excesses of up to 7 x 10(18) M(-2) are measured. The segregation is related to the presence of misfit dislocations at the interfaces of the coarse preciptitates, while the thin plates remain coherent with no detectable segregation.

Journal Article↗

PubMed1999

Kinetic study on thermal denaturation of hen egg-white lysozyme involving precipitation.

A kinetic study on the thermal denaturation accompanying precipitation of hen egg-white lysozyme was performed at temperatures between 50 and 90 degrees C. Visible precipitation occurred at lysozyme concentrations higher than 10(-5)M. Even at the concentration of 10(-6)M where no visible precipitation was observed, irreversible and reversible denaturation could be clearly discriminated. The former involves two different reactions with activation energies of approximately 93 and 50 kJ x mol(-1). On the other hand, enthalpy and entropy changes in the latter are 443 kJ x mol(-1) and 1280 J x K(-1) x mol(-1), respectively, indicating a large conformational change. The contradiction that the denaturation or deactivation reaction fitted first-order reaction kinetics while its rate constant depended on the protein concentration, was resolved by newly proposed schemes. The apparent first-order rate constant obtained experimentally depended on the initial protein concentration being on the order of almost unity. Moreover, it was revealed that the apparent first-order reaction involved a second-order reaction that characterized the aggregation of denatured protein molecules. The theory developed here explained reasonably the thermal denaturation accompanying precipitation that occurs at high protein concentration and at high temperature, and was also successfully applied to the lower concentration range with no accompanying precipitation.

Journal Article↗

PubMed1995

Precipitating and predisposing factors of acute confusional state among emergency department patients.

The aim of this study was to examine predisposing and precipitating factors of acute confusional state (ACS) retrospectively in medical records of patents examined in an acute medical unit (AMU) who had a preliminary diagnosis of confusion/anxiety. The study comprised all 221 patients who were 65 years old and older among the 18,015 patients examined in the AMU during 1 year who, after a preliminary examination in the AMU, received a diagnosis of confusion/anxiety without any other etiologic diagnosis. Fifty-six cases fulfilled the DSM-III-R criteria for ACS. The control group comprised 165 patients, with anxiety, depression, or psychosis the main finding in 135 cases. Among patients further examined in other departments or for whom consultations were made, the medical records showed that the ACS group had on average 2.6 predisposing factors for ACS, with dementia, cerebrovascular disease, and sensory deficits the most common. Three to six predisposing factors were found among 46% of the ACS patients, compared to 4% of the control group. A precipitating factor of ACS was found in 78% of the ACS cases, and the average number of precipitating factors was 1.6. Dementia (32%), metabolic disturbances (30%), and cardiovascular diseases (16%) were the most frequent precipitating factors among the ACS group. The mortality rates 2 years after examination in the AMU were 32% for the ACS group and 20% for the control group (p <.05). The study suggests that the causes of ACS are often multifactorial and that it is important to seek several precipitating factors when treating this potentially reversible condition.

Adult↗

PubMed1999

Strategies for recombinant protein recovery from canolaby precipitation

Transgenic plants may prove to be one of the most economical systems for the large-scale production of proteins and peptides. Our goal is to develop an approach for protein recovery from canola that will be adaptable to a wide variety of recombinant proteins. For recombinant protein recovery, the two downstream processes considered were extraction of target protein and purification of recombinant protein from host proteins and other impurities. In these experiments, T4 lysozyme has been added to the canola extracts as an example protein to simulate recovery of recombinant proteins while evaluating the merits of several candidate precipitation strategies to understand selectivity behavior and how it might be affected by the presence of canola components. The ability of precipitating agents, such as acid and the polyelectrolytes Glass H and poly(acrylic acid) (PAA), was investigated. Approximately 70% of extracted canola proteins were precipitated by acid addition to pH 5, leaving about 90% of T4 lysozyme still in solution. Targeting T4 lysozyme for the precipitate phase by addition of oppositely charged polyelectrolyte was not successful in the presence of canola components. Addition of 2.5 times the PAA dosage required to precipitate pure T4 lysozyme to the spiked canola extract brought down only 40% of the T4 lysozyme. For the comparable result with Glass H, a 9 times higher dosage was required.

Journal Article↗