Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.16.2 (PCP)
 3,761 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Heavy metals and chloro-organic compounds can influence female fertility at every phase of reproduction. They may induce hormonal disorders, preventing ovulations and pregnancies. They can also result in abortions and fetal malformations. For this reason, the urinary excretion of heavy metals was measured after oral load with the chelating agent dimercaptopropanesulfonate (Dimaval) in women with hormonal irregularities. In addition, blood was examined for various polychlorinated compounds (polychlorinated biphenyls - PCB -, hexachlorocyclohexane - HCH -, pentachlorophenole - PCP -, hexachlorobenzol - HCB -, dichlordiphenyltrichloroethane - DDT -, dichlorodiphenylethane - DDE -, tetrachlorodiphenylethane - DDD -). Mercury contaminations were seen most commonly and correlated significantly with the number of amalgam fillings and with the release of mercury while chewing. The latter was demonstrated with the so-called chewing-gum test. Women with hormonal disorders or alopecia had, on the average, the highest mercury excretion during the wash-out test. Cadmium excretion was pronounced for the following groups of women: those with technical professions, those suffering from thyroid dysfunctions, and those with habitual abortions and uterine fibroids. With increasing age, pesticide concentrations of the blood rose significantly. Women with endometriosis and with antihyroidal antibodies had significantly higher PCB values. Despite therapeutic intervention, fewer women with elevated DDT/DDE/DDD values conceived when compared to those with lower values. alpha-HCH concentrations were often elevated in women with uterine fibroids. With increasing PCP levels pregnancies often ended in abortion. Results of this investigation indicate that women with hormonal irregularities or specific fertility disorders should be examined for heavy metal and pesticide contamination prior to hormone treatment.
 ...
PMID:[The limits of hormone substitution in pollutant exposure and fertility disorders]. 128 83

We studied nine patients (56 +/- 7 years) with complete AV-block and permanent dual-chamber pacemaker (DDD) under different pacing modes: ventricle pacing (VVI) 70 bpm, DDD 106 +/- 4 bpm, rate adaptive pacing (VVI-FA) 108 +/- 3 bpm. Exercise was performed supine on the bicycle ergometer at 50 watts for 5 min at each setting. DDD-paced patients showed significantly higher mixed venous oxygen saturation, being 45 +/- 2% after the fourth minute, (VVI 38 +/- 2%, p less than 0.01 and VVI-FA paced patients 40 +/- 1%, p less than 0.01). Pressures were normal under DDD pacing during exercise (RAP 7 +/- 2 mm Hg; PCP 14 +/- 3 mm Hg) and showed further increase to abnormal levels during VVI (RAP 13 +/- 2 mm Hg, p less than 0.01; PCP 21 +/- 3 mm Hg, p less than 0.02) and VVI-FA pacing (RAP 10 +/- 2 mm Hg, p less than 0.05; PCP 20 +/- 3 mm Hg, p less than 0.01). Stroke volume increased from 71 +/- 5 ml to 105 +/- 7 ml during VVI and from 64 +/- 7 ml to 81 +/- 7 ml during DDD pacing. Stroke volume remained unchanged (69 +/- 5 ml) during VVI-FA pacing. The peak levels of ANP during and after exercise were significantly higher under VVI (951 +/- 248 pg/ml) than under DDD pacing (650 +/- 140 pg/ml, p less than 0.01) and were not different between DDD and VVI-FA pacing (677 +/- 97 pg/ml). These results show that VVI pacing effects a more pronounced increase of ANP level than other pacing modes. Under moderate exercise, rate-responsive pacing compared to VVI pacing showed no differences in mixed venous oxygen saturation and in atrial pressures. Only DDD pacing showed higher oxygen saturation and a normalization of atrial pressures when compared to other types of single chamber pacing.
 ...
PMID:[Effect of AV synchronization and rate increase on hemodynamics and on atrial natriuretic peptide in patients with total AV block]. 214 4

A haemodynamic and M mode echocardiographic study of 57 patients hospitalised for chronic, symptomatic 2nd or 2rd degree AV block was carried out after 3 periods of pacing, each lasting 2 hours : 1) sequential AV pacing ( SAV ) with a 200 ms delay, considered as the mode of reference; 2) sequential ventriculo-atrial pacing ( SVA ) with the same sequential delay, recreating equivalent conditions of 1/1 ventriculo-atrial conduction (VAC); 3) ventricular pacing (V) recreating complete AV dissociation ( CAVD ). The pacing rate was the same for each patient (89 +/- 9/min). In comparison with SAV , SVA caused much worse haemodynamic changes than V : large increases in mean atrial pressures (+161% and +64% in RAP and PCP respectively); "canon" atrial A waves which were poorly tolerated (mean amplitude 14 mmHg and 18 mmHg on the RA and PCP waves respectively); in some cases, a large fall in blood pressure was observed due to the failure of systemic resistances to increase and compensate for the constant decrease in pump function (mean reduction of 23% of cardiac index; 29% of LV work index). These changes are much more pronounced in diseased than in healthy hearts, especially in the presence of mitral or tricuspid regurgitation. Echocardiography showed the main cause of these haemodynamic changes to be a reduction in ventricular filling with significant reductions in LV systolic and diastolic dimensions, changes in the mitral valve echos (reduction in the opening and closing velocities, delayed closure), probably related to a decrease in transvalvular blood flow, and decreased regional contractility of the interventricular septum. These observations justify an increase in the indications of modes of pacing maintaining permanent atrio-ventricular sequence (VVI pacing at slow rates; AAI pacing, DVI or DDD pacing in cases of abnormal AV conduction with VAC, especially in cases of sick sinus syndrome with permanent bradycardia). These modes of pacing are particularly beneficial when the electrical abnormality is associated with a decompensated cardiac lesion, or with decreased ventricular compliance or mitral regurgitation.
 ...
PMID:[Hemodynamics and M mode echocardiography of the consequences of ventriculo-atrial conduction in the human]. 642 28

Dual chamber pacing has been proposed as an alternative treatment to patients with cardiac failure refractory to optimal medical therapy. The influence of the site of ventricular pacing was studied in 15 patients with an average age of 68.7 +/- 8.7 years with dilated cardiomyopathies and an average left ventricular ejection fraction of 22.3 +/- 6.8%. Three temporary USCI electrodes were positioned in the right atrium, the right ventricular outflow tract (RVOT) and the right ventricular apex. The average duration of the QRS complexes and the haemodynamic parameters (PAP, PCP and cardiac index) were measured in sinus rhythm and during DDD apical, RVOT and simultaneous apical and RVOT pacing. The RVOT and simultaneous pacing significantly reduced the QRS duration (135 +/- 14 ms and 137 +/- 17 ms, p < 0.0001 respectively) compared with apical pacing (150 +/- 19 ms). The mean PAP and mean PCP remained unchanged in the different modes of pacing but the cardiac index increased significantly during RVOT pacing (2.99 +/- 0.67 l/min/m2) and simultaneous pacing (3 +/- 0.77 l/min/m2) compared with apical pacing (2.66 +/- 0.62 l/min/m2) (p < 0.001 and p < 0.01 respectively) and compared with sinus rhythm (2.62 +/- 0.7 l/min/m2) (p < 0.001 and p < 0.005 respectively). This study suggests that better results may be obtained with RVOT screw in lead than with the traditional right ventricular apical electrode.
 ...
PMID:[Comparison of apical and infundabular pacing in patients with primary dilated or ischemic cardiomyopathy]. 1006 78

A method for the prediction of a suitable solvent for the extraction of pesticides is outlined. The procedure is based on the Hildebrand solubility parameter, delta(t). The solubility parameter is broken down into three individual components, which are calculated by the addition of group contributions. To demonstrate the applicability of the approach pressurized fluid extraction was used to extract 4,4'-DDT [1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane] and its metabolites, 4,4'-DDD [1,1-dichloro-2,2-bis(p-chlorophenyl)ethane] and 4,4'-DDE [1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene], from an historically contaminated soil from the United States and pentachlorophenol from a certified reference material (CRM524) using various solvents. Visual representation of the individual parameters predicted the ideal extraction solvent to be DCM for 4,4'-DDT and its metabolites and a mixture of acetonitrile and dichloromethane (1:1, v/v) for PCP. These findings were confirmed by the experimental results.
 ...
PMID:Extraction solvent selection in environmental analysis. 1179 21

A procedure to assess the bioavailability of persistent organic pollutants (POPs) from soil samples has been developed. The procedure is based on the use of simulated in vitro gastrointestinal extraction to remove POPs from soil matrices. The level of recovery, using this approach, is assessed following liquid-liquid extraction (LLE) and analysis by gas chromatography-mass selective detection (GC-MSD). The remaining soil residue is then extracted using pressurised fluid extraction (PFE) followed by GC-MSD analysis to assess the residual fraction. The residual fraction is monitored to determine the unavailable fraction i.e. not available for absorption in the gastrointestinal tract of humans. The procedure was applied to four soil samples i.e. an aged, spiked soil and three certified reference materials (CRMs) contaminated with POPs. Recoveries of pesticides (lindane, endosulfan I, endrin, DDE, DDD and endosulfan II), phenols (cresol, TCP and PCP), and base neutral compounds (hexachloroethane, acenaphthene, dibenzofuran, fluorene and hexachlorobenzene) from aged, spiked soil following extraction with gastric fluid ranged from 0.8 to 8.3% while following intestinal extraction ranged from 5.5 to 13.5%, irrespective of POP. Recoveries of pesticides (lindane, endosulfan I, endrin, DDE, DDD and endosulfan II) from CRM 805-050 following extraction with gastric fluid were below the limit of detection while following intestinal extraction ranged from 5.3 to 12.8%. Recoveries of phenols (cresol, TCP and PCP) from CRM 401-225 following extraction with gastric fluid ranged from 1.6 to 2.0% while following intestinal extraction ranged from 4.1 to 5.4%. Recoveries of base neutral acid analytes (hexachloroethane, acenaphthene, dibenzofuran, fluorene and hexachlorobenzene) from CRM 107-100 following extraction with gastric fluid ranged from 1.4 to 4.0% while following intestinal extraction ranged from 6.6 to 12.7%. It has been found that the majority of POPs present i.e. >75%, would be excreted if consumed and not be absorbed in the gastrointestinal tract of humans.
 ...
PMID:An assessment of the bioavailability of persistent organic pollutants from contaminated soil. 1598 51