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1.
Eat Behav ; 9(1): 91-101, 2008 Jan.
Article in English | MEDLINE | ID: mdl-18167327

ABSTRACT

OBJECTIVE: The current study explored family and individual variables associated with dieting and binge eating. METHOD: 581 college females completed questionnaires exploring the amount of criticism and preoccupation with weight and food they experienced in their families, their current levels of depression, external attributions, and body esteem, and their degree of focus on dieting and binge eating. RESULTS: A structural equation model incorporating previous research and theoretical considerations was evaluated. The data were consistent with a model in which family variables were mediated by individual variables of depression, external attributions, and negative body esteem to predict dieting and bingeing. Dieting was influenced by all three individual variables, and in turn, dieting and depression were associated with binge eating. DISCUSSION: These results are consistent with an internalization model of family issues. Family dysfunction and values lead to depressive symptoms, external attributions, and negative body esteem. Dieting may be a "solution" that leads to additional eating problems such as binge eating when depression is present.


Subject(s)
Bulimia Nervosa/genetics , Feeding Behavior , Students/psychology , Students/statistics & numerical data , Universities , Adolescent , Adult , Affect , Attitude , Bulimia Nervosa/epidemiology , Bulimia Nervosa/psychology , Depressive Disorder/diagnosis , Depressive Disorder/epidemiology , Depressive Disorder/psychology , Family , Female , Food Preferences , Humans , Prospective Studies , Self Concept , Surveys and Questionnaires
2.
Chemosphere ; 62(6): 961-7, 2006 Feb.
Article in English | MEDLINE | ID: mdl-16081131

ABSTRACT

This study describes an investigation using tropical water lilies (Nymphaea spontanea) to remove hexavalent chromium from aqueous solutions and electroplating waste. The results show that water lilies are capable of accumulating substantial amount of Cr(VI), up to 2.119 mg g(-1) from a 10 mg l(-1) solution. The roots of the plant accumulated the highest amount of Cr(VI) followed by leaves and petioles, indicating that roots play an important role in the bioremediation process. The maturity of the plant exerts a great effect on the removal and accumulation of Cr(VI). Plants of 9 weeks old accumulated the most Cr(VI) followed by those of 6 and 3 weeks old. The results also show that removal of Cr(VI) by water lilies is more efficient when the metal is present singly than in the presence of Cu(II) or in waste solution. This may be largely associated with more pronounced phytotoxicity effect on the biochemical changes in the plants and saturation of binding sites. Significant toxicity effect on the plant was evident as shown in the reduction of chlorophyll, protein and sugar contents in plants exposed to Cr(VI) in this investigation.


Subject(s)
Chromium/metabolism , Nymphaea/metabolism , Water Pollutants, Chemical/metabolism , Biodegradation, Environmental , Carbohydrate Metabolism , Chlorophyll/metabolism , Chromium/isolation & purification , Chromium/toxicity , Copper , Electroplating , Industrial Waste , Nymphaea/drug effects , Plant Leaves/drug effects , Plant Leaves/metabolism , Plant Roots/drug effects , Plant Roots/metabolism , Proteins/metabolism , Waste Disposal, Fluid , Water Pollutants, Chemical/isolation & purification , Water Pollutants, Chemical/toxicity
3.
Psychol Bull ; 131(5): 713-737, 2005 Sep.
Article in English | MEDLINE | ID: mdl-16187855

ABSTRACT

The present meta-analysis examined the stability of vocational interests from early adolescence (age 12) to middle adulthood (age 40). Stability was represented by rank-order and profile correlations. Interest stability remained unchanged during much of adolescence and increased dramatically during the college years (age 18-21.9), where it remained for the next 2 decades. Analyses of potential moderators showed that retest time interval was negatively related to interest stability and that rank-order stability was less stable than profile stability. Although cohort standings did not moderate stability, interests of the 1940s birth cohort were less stable than those of other cohorts. Furthermore, interests reflecting hands-on physical activities and self-expressive/artistic activities were more stable than scientific, social, enterprising, and clerical interests. Vocational interests showed substantial continuity over time, as evidenced by their higher longitudinal stability when compared with rank-order stability of personality traits. The findings are discussed in the context of psychosocial development.


Subject(s)
Career Choice , Motivation , Occupations , Adolescent , Adult , Child , Humans , Longitudinal Studies , Middle Aged
4.
Environ Technol ; 24(10): 1243-51, 2003 Oct.
Article in English | MEDLINE | ID: mdl-14669804

ABSTRACT

The sorption characteristics of Cr(VI) and Cu(II) by ethylenediamine modified rice hull from single and binary metal ion solutions were evaluated under various experimental conditions. Optimal Cr(VI) and Cu(II) removal from single metal ion solutions occurred at pH 2.0 and 5.5, respectively. Simultaneous removal of Cr(VI) and Cu(II) occurred at pH greater than 3.0. The sorption kinetics of Cr(VI) and Cu(II) from single and binary metal ion solutions were studied with reference to metal concentration, agitation rate and particle size. Sorption of Cr(VI) was more rapid than Cu(II). The kinetics of metal ion sorption fitted a pseudo-second order expression. The variation in the initial uptake rates was very small at an agitation rate beyond 150 rpm and sorption was generally independent of particle size. Equilibrium sorption data could be fitted into the Langmuir isotherm equation. Maximum sorption capacities of ethylenediamine modified rice hull for Cr(VI) at pH 2 and Cu(II) at pH 4 in single metal solutions were 0.45 and 0.06 mmol g(-1), respectively. This corresponds to an enhancement factor of 2.6 and 3 fold for Cr(VI) and Cu(II), respectively, compared to natural rice hull. A synergistic effect was observed for sorption of these ions in binary metal solutions.


Subject(s)
Carcinogens, Environmental/chemistry , Carcinogens, Environmental/isolation & purification , Chromium/chemistry , Chromium/isolation & purification , Copper/chemistry , Copper/isolation & purification , Ethylenediamines/chemistry , Water Pollutants/isolation & purification , Adsorption , Biodegradation, Environmental , Oryza , Particle Size
5.
J Forensic Odontostomatol ; 21(1): 17-22, 2003 Jun.
Article in English | MEDLINE | ID: mdl-12793127

ABSTRACT

Denture marking is accepted as a means of identifying dentures and persons in geriatric institutions, or post-mortem during war, crimes, civil unrest, natural and mass disasters. Labelling on the acrylic resin component of the denture can easily be damaged or destroyed by fire but on cobalt-chromium components it would be more resistant. A copper vapour laser (CVL) can be used to label the cobalt-chromium components of dentures and metal restorations easily, and legibly, and miniaturised for the incorporation of more personal particulars necessary for the identification of the deceased person. The CVL beam is focussed by its optics and delivered to the material surface by the two-axis scanner mounted with mirrors. A personal computer controls the movement of the scanner and the firing of the CVL. The high peak power of the pulsed CVL is focussed to very high energy density producing plasma ablation of the alloy surface. Very fine markings of a few microns width can be produced enabling the storage of detailed information of the deceased person on a metal surface for the purpose of rapid identification.


Subject(s)
Dental Alloys , Dental Restoration, Permanent , Denture Identification Marking/methods , Dentures , Lasers , Chromium Alloys/chemistry , Copper/chemistry , Dental Alloys/chemistry , Denture Identification Marking/instrumentation , Forensic Dentistry , Humans , Miniaturization , Volatilization
6.
Environ Technol ; 24(2): 197-204, 2003 Feb.
Article in English | MEDLINE | ID: mdl-12675017

ABSTRACT

Spent bleaching earth, an industrial waste produced after the bleaching of crude palm oil, was investigated for its potential in removing Cr(VI) from aqueous solution. The earth was treated with different amounts of sulfuric acid and under different activation temperatures. Results show that the optimum treatment process involved 10% sulfuric acid at 350 degrees C. The effects of contact time, pH, initial concentration, sorbent dosage, temperature, sorption isotherms and the presence of other anions on its sorption capacity were studied. Isotherm data could be fitted into a modified Langmuir isotherm model implying monolayer coverage of Cr(VI) on acid activated spent bleaching earth. The maximum sorption capacity derived from the Langmuir isotherm was 21.2 mg g(-1). This value was compared with those of some other low cost sorbents. Studies of anion effect on the uptake of Cr(VI) on acid activated spent bleaching earth provided the following order of suppression: EDTA >PO4(3-)>SO4(2-)>NO3(-)>Cl(-).


Subject(s)
Carcinogens, Environmental/chemistry , Chromium/chemistry , Industrial Waste , Plant Oils , Adsorption , Environmental Pollution/prevention & control , Hydrogen-Ion Concentration , Palm Oil , Solubility , Sulfuric Acids , Temperature
7.
Chemosphere ; 50(1): 23-8, 2003 Jan.
Article in English | MEDLINE | ID: mdl-12656225

ABSTRACT

A study on the modification of rice husk by various carboxylic acids showed that tartaric acid modified rice husk (TARH) had the highest binding capacities for Cu and Pb. The carboxyl groups on the surface of the modified rice husk were primarily responsible for the sorption of metal ions. A series of batch experiments using TARH as the sorbent for the removal of Cu and Pb showed that the sorption process was pH dependent, rapid and exothermic. The sorption process conformed to the Langmuir isotherm with maximum sorption capacities of 29 and 108 mg/g at 27 +/- 2 degrees C for Cu and Pb, respectively. The uptake increased with agitation rate. Decrease in sorbent particle size led to an increase in the sorption of metal ions and this could be explained by an increase in surface area and hence binding sites. Metal uptake was reduced in the presence of competitive cations and chelators. The affinity of TARH for Pb is greater than Cu.


Subject(s)
Copper/chemistry , Lead/chemistry , Oryza , Tartrates/chemistry , Waste Disposal, Fluid/methods , Water Pollutants, Chemical/analysis , Adsorption , Hydrogen-Ion Concentration , Kinetics , Particle Size , Solutions , Surface Properties/drug effects
8.
J Pharm Sci ; 90(12): 2023-31, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11745761

ABSTRACT

All-trans-retinoyl-beta-D-glucuronide (RAG) is an endogenous active metabolite of all-trans-retinoic acid (ATRA). In the present study, the pharmacokinetics of RAG was examined after the administration of a single intravenous does (5, 10, or 15 micromol/kg) and of multiple daily intravenous doses (5 micromol/kg) to rats for 8 days. The plasma concentrations of RAG and ATRA were measured by a reverse-phase HPLC method. A rapid distribution phase of approximately 1 h was observed in all of the rats after single or multiple doses. Thereafter, RAG was eliminated through a first-order process, in accord with a typical two-compartment first order pharmacokinetic profile. After single intravenous doses, the AUC of RAG increased proportionally with the dose and the clearance remained unchanged within the tested doses. There was no statistical significant difference in distribution rate constants from central compartment to peripheral compartment (K(12)) and from peripheral compartment to central compartment (K(21)) between different doses. However, as the dose increased from 5 micromol/kg to 10 micromol/kg, the volume of distribution at the steady state (V(ss)) and the volume of peripheral compartment (V(p)) decreased significantly (p < 0.05) from 1.290 +/- 0.269, 0.928 +/- 0.232. L/kg to 0.961 +/- 0.149, 0.647 +/- 0.107 L/kg, respectively. V(ss) and V(p) at a dose of 15 micromol/kg (0.924 +/- 0.187, 0.698 +/- 0.165 L/kg) were not significantly different from that at 10 micromol/kg. Thus, RAG might saturate the tissue-binding sites at higher doses. ATRA was detected as a metabolite of RAG at low levels (usually < 0.05 microM) only in the first 2 h after intravenous administration. RAG clearly was not extensively hydrolyzed to ATRA in our study. After multiple daily intravenous administration of RAG, the clearance (Cl) and the elimination rate constant (K(10)) remained unchanged (p > 0.05), indicating that long-term daily administration of RAG did not induce its accelerated metabolism. However, K(12), V(p), and V(ss) declined significantly (p < 0.05) from 1.67 +/- 0.54 h(-1), 0.928 +/- 0.232 L/kg, and 1.290 +/- 0.269 L/kg to 0.96 +/- 0.48 h(-1), 0.494 +/- 0.147 L/kg, and 0.818 +/- 0.187 L/kg, respectively. Therefore, long-term daily dosing of RAG seemed to decrease its distribution profile. Although the AUC of RAG did not change significantly after multiple dosing, the AUC of ATRA after RAG dosing significantly declined (p < 0.05) from 0.032 +/- 0.019 microM x h to 0.010 +/- 0.006 microM x h. The decline in the AUC of ATRA might reflect an increase in its uptake by tissue and/or in its metabolism. Because enhanced clearance is not associated with RAG after multiple administrations, RAG could be considered as an alternate to ATRA in appropriate clinical applications.


Subject(s)
Tretinoin/analogs & derivatives , Tretinoin/administration & dosage , Tretinoin/pharmacokinetics , Animals , Drug Administration Schedule , Injections, Intravenous , Male , Rats , Rats, Sprague-Dawley , Tretinoin/blood , Vitamin A/administration & dosage , Vitamin A/blood , Vitamin A/pharmacokinetics
9.
Appl Biochem Biotechnol ; 90(1): 75-87, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11257809

ABSTRACT

The potential of quaternized wood (QW) chips in removing hexavalent chromium from synthetic solution and chrome waste under both batch and continuous-flow conditions was investigated. Sorption was found to be dependent on pH, metal concentration, and temperature. QW chips provide higher sorption capacity and wider pH range compared with untreated wood chips. The equilibrium data could be fitted into the Langmuir isotherm model, and maximum sorption capacities were calculated to be 27.03 and 25.77 mg/g in synthetic chromate solution and chrome waste, respectively. The presence of sulfate in high concentration appeared to suppress the uptake of chromium by QW chips. Column studies showed that bed depth influenced the breakthrough time greatly whereas flow rate of influent had little effect on its sorption on the column.


Subject(s)
Chromium/metabolism , Hazardous Waste , Industrial Waste , Wood , Adsorption , Anions/metabolism , Carcinogens, Environmental/metabolism , Chromatography , Costs and Cost Analysis , Hydrogen-Ion Concentration , Temperature , Thermodynamics , Time Factors
10.
Appl Biochem Biotechnol ; 87(3): 233-45, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10982232

ABSTRACT

Various species of local wood modified with N-(3-chloro-2-hydroxypropyl)-trimethylammonium chloride showed sorption enhancement for hydrolyzed Reactive Blue 2 (HRB) compared to the untreated samples. The enthalpy of sorption of HRB on Simpoh (Dillenia suffruticosa) was found to be endothermic. Maximum sorption capacity calculated from the Langmuir isotherm was 250.0 mg/g. Under continuous flow conditions HRB could be successfully removed. Dye removal was a function of bed depth and flow rate. However, the bed depth service time model of Bohart and Adams was not applicable in the HRB-quaternized wood system. The modified wood was applied to a sample of industrial textile effluent, and it was found to be able to remove the color successfully under batch conditions.


Subject(s)
Adsorption , Coloring Agents/chemistry , Wood , Chromatography , Kinetics , Quaternary Ammonium Compounds/chemistry , Spectrophotometry , Temperature , Time Factors , Triazines/chemistry , Water Pollution, Chemical/prevention & control
11.
J Pharm Sci ; 89(2): 260-7, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10688755

ABSTRACT

all-trans-Retinoic acid (ATRA, vitamin A acid, or tretinoin) is a potent chemotherapeutic agent for the treatment of acute promyelocytic leukemia (APL). Its poor aqueous solubility not only affects its oral absorption but also prevents it from forming an aqueous parenteral formulation. Recently, we developed a water-soluble formulation of ATRA with 2-hydroxypropyl-beta-cyclodextrin (HPbetaCD). In present study, this formulation was tested in Sprague-Dawley rats. Kinetic study of ATRA was carried out after oral or intravenous administration. Though there were no statistical differences in any of the estimated pharmacokinetic parameters between ATRA sodium salt and HPbetaCD-based ATRA after intravenous administration, inclusion of ATRA into HPbetaCD was found to greatly improve the oral absorption of ATRA.


Subject(s)
Antineoplastic Agents/pharmacokinetics , Cyclodextrins/pharmacokinetics , Tretinoin/pharmacokinetics , beta-Cyclodextrins , 2-Hydroxypropyl-beta-cyclodextrin , Administration, Oral , Animals , Antineoplastic Agents/administration & dosage , Biological Availability , Body Fluid Compartments , Cyclodextrins/administration & dosage , Injections, Intravenous , Intestinal Absorption , Male , Rats , Rats, Sprague-Dawley , Solubility , Tretinoin/administration & dosage , Water/chemistry
12.
Acta Crystallogr C ; 56(Pt 3): E113-4, 2000 Mar 15.
Article in English | MEDLINE | ID: mdl-15263222

ABSTRACT

Bis(N,N-dimethylthiocarbamoylthio)acetic acid, [(CH(3))(2)NC(=S)S](2)CHC(=O)OH or C(8)H(14)N(2)O(2)S(4), exists as a centrosymmetric hydrogen-bonded dimer [O.O 2.661 (3) A].

14.
Immunohematology ; 14(2): 68-71, 1998.
Article in English | MEDLINE | ID: mdl-15377200

ABSTRACT

A comparative study of 164 serum samples was carried out to determine the specificity and sensitivity of the indirect antiglobulin test (IAGT) in three different formulations: physiologic saline, low-ionic solution (RAM), and RAM supplemented with polyethylene glycol (PEG). Serum samples containing mostly weak antibodies (anti-D, -C, -E, -c, -Jka, -Fya, -K, -S, -Lea, -Lua, -M, -Cob, -P1, -I, and -Kna) were used in a 10-minute IAGT in which PEG-IAGTs were compared with saline- IAGTs and RAM-IAGTs. With the exception of anti-P1, anti-I, and an anti-Lea, PEG-IAGTs detected all the antibodies tested compared with 72.3% and 77.4% for saline-IAGTs and RAM-IAGTs, respectively. The end-point titers of at least 82% of antibodies detected by PEG-IAGTs were 1-3 dilutions higher than those by saline- and RAM-IAGTs. When specificity of PEG-IAGTs was tested using 268 randomly selected, fresh (< 1 day old) blood samples, PEG-IAGT detected 11 out of 268 samples as positive compared with 7 out of 268 by both saline-IAGTs and RAM-IAGTs. The four antibodies that were not detected were identified as anti-D, anti-E, anti-Bga, and an autoantibody known previously to be only reactive with papain-pretreated red cells. No nonspecific reactions were detected by PEG-IAGTs and no hemolysis was evident in any of the IAGTs. PEG-IAGTs were more sensitive than saline- and RAM-IAGTs. PEG-IAGTs detected all weak, clinically significant antibodies as well as four antibodies that were otherwise undetected by saline-IAGT or RAM-IAGT. The overall sensitivity of the PEGIAGT was 96.3% compared with 84.1% and 73.2% for the RAM- and saline-IAGT, respectively.

18.
Toxicon ; 32(5): 573-81, 1994 May.
Article in English | MEDLINE | ID: mdl-8079369

ABSTRACT

Stonustoxin (8-50 micrograms/ml) produced a rapid and concentration-dependent rise in tension (contracture) of the electrically stimulated mouse hemidiaphragm followed by a gradual waning of tension from the peak to the baseline; the nerve-evoked and the directly (muscle)-evoked twitches of the hemidiaphragm were also progressively and irreversibly blocked in a time- and concentration-dependent manner. Stonustoxin (22 and 44 micrograms/ml) produced a similar rapid rise in tension of the chick biventer cervicis muscle as well as irreversible and concentration-dependent blockade of nerve-evoked twitches and contractures produced by acetylcholine (200 microM), carbachol (8 microM) and KCl (40 mM). The muscle contracture produced by stonustoxin was blocked by dantrolene sodium (6 microM) but not by tubocurarine (15 microM). Moreover, stonustoxin (40 micrograms/ml) did not inhibit nerve conduction in the toad sciatic nerve and stonustoxin (60 micrograms/ml) did not exhibit any anticholinesterase activity. The inhibition of neuromuscular function by stonustoxin in the mouse hemidiaphragm and chick biventer cervicis muscle can therefore be attributed to some irreversible myotoxic action(s) of the toxin, whereas the stonustoxin-induced muscle contractures could have been mediated via depolarization of muscle fibres.


Subject(s)
Diaphragm/physiology , Fish Venoms/pharmacology , Muscle Contraction/drug effects , Neuromuscular Blocking Agents/pharmacology , Animals , Bufonidae , Chickens , Diaphragm/drug effects , Evoked Potentials/drug effects , Male , Mice , Neuromuscular Junction/drug effects , Rats , Rats, Sprague-Dawley , Sciatic Nerve/drug effects , Sciatic Nerve/physiology
19.
Pharmacol Ther ; 64(3): 509-28, 1994.
Article in English | MEDLINE | ID: mdl-7724660

ABSTRACT

Venoms from stonefish (genus Synanceja) have marked effects on the cardiovascular and neuromuscular systems and on vascular permeability; the venoms also exhibit haemolytic and hyaluronidase activity. Recently, a toxic protein, stonustoxin (SNTX), was purified from the venom of S. horrida: the primary lethal action of SNTX has been attributed to its potent endothelium-dependent vasorelaxant activity causing a rapid, marked and irreversible hypotension; the other actions of SNTX resemble those of the stonefish crude venoms.


Subject(s)
Fish Venoms , Fishes/physiology , Marine Toxins , Amino Acid Sequence , Animals , Fish Venoms/chemistry , Fish Venoms/metabolism , Fish Venoms/toxicity , Fishes/anatomy & histology , Humans , Marine Toxins/chemistry , Marine Toxins/metabolism , Marine Toxins/toxicity , Molecular Sequence Data
20.
Toxicon ; 31(11): 1471-8, 1993 Nov.
Article in English | MEDLINE | ID: mdl-8310447

ABSTRACT

Stonefish venom has been documented to cause marked hypotension and respiratory difficulties in envenomed animals. Stonustoxin, a lethal protein recently isolated from the venom of the stonefish Synanceja horrida produced hypotension and, at concentrations above 20 micrograms/kg, death in anaesthetized rats, with no observable effects on nerve-evoked twitches of the tibialis and diaphragm muscles. Stonustoxin (20-160 ng/ml) induced endothelium-dependent relaxations of rat thoracic aortae precontracted with noradrenaline. Higher concentrations induced relaxations followed by contractions. Methylene blue, haemoglobin and the specific NO-synthase inhibitor L-NG-nitro arginine methyl ester inhibited stonustoxin-induced relaxations, while the cyclooxygenase inhibitor indomethacin was without effect. The results of the present study show that stonustoxin causes marked vasorelaxation of the rat isolated aorta, which appears to be due to the release of endothelium-derived relaxing factor (probably nitric oxide or nitric oxide-yielding substances) from the vascular endothelium, and this may be responsible for the in vivo hypotensive and lethal actions of stonustoxin and of stonefish venom.


Subject(s)
Endothelium, Vascular/physiology , Fish Venoms/pharmacology , Vasodilator Agents/pharmacology , Animals , Aorta, Thoracic/drug effects , Blood Pressure/drug effects , Endothelium, Vascular/drug effects , In Vitro Techniques , Male , Muscles/drug effects , Nitric Oxide/physiology , Rats , Rats, Sprague-Dawley
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