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Autopsy findings and the results of chemical-toxicological analysis are presented on a case of suicide with a wood preservative containing potassium fluoride. The highest amounts of fluoride were found in kidney and urine; there was no increase of fluorides amount in the brain. The analysis was done by colorimetry after micro-diffusion.
We studied the effects of oral taurine supplementation on bile acids conjugation and duodenal bile salt concentrations in infants. Seventeen infants receiving enteral artificial nutrition were investigated. At the beginning of the study they were 6 to 14 weeks old, in good nutritional state, without malabsorption, protein-losing enteropathy and liver or infectious diseases. After at least 8 days of a stable, taurine-free regimen the infants received oral taurine supplementation (36-45 micromol/kg.24 h) for 8 days. Bile acids were measured before and after each supplementation period in bile samples obtained by duodenal tubing, using enzymatic methods and colorimetry. According to the initial plasma taurine levels before supplementation, the infants were divided into two groups: I) plasma taurine levels less than 60 mumol/l (mean 47 +/-5 mumol/l, n = 8); II) plasma taurine levels greater than 70 mumol/l (mean 77 +/- 2 mumol/l, = 9). After 8 days of taurine supplementation a significant increase of plasma and urinary taurine (P less than 0.01),total duodenal bile salt concentrations (P less than 0.05), total duodenal tauroconjugates (P less than 0.05),taurocholate (P less than 0.01), taurochenodeoxycholate (P less than 0.05), and glycocholate (P less than 0.01), duodenal concentrations, and a significant decrease of the glycoconjugate/tauroconjugate ratio (P less than 0.05), were observed, but only in group I. in group II infants we only noted a significant increase of urinary taurine (P less than 0.01), and of duodenal total tauroconjugates (P less than 0.05). This study shows that the biliary effects of an oral taurine supplementation depends on taurine status and that in taurine-depleted infants intakes of exogenous taurine higher than 45 mumol/kg. 24 h are perhaps necessary for optimal bile salt effects.
The influence of hypoglycemia on pituitary and cortical and medullary adrenal response was studied in Holstein X Friesian male calves by giving an intravenous injection of bovine insulin (0.2 U/kg b.w.). Seventeen (9 treated and 8 control) calves were born spontaneously at term (278 days) and 9 (5 treated and 4 control) were delivered by caesarean section on day 260 of gestation. Insulin injections were given 1, 5, 10 and 30 days after birth. Plasma insulin and ACTH concentrations were measured by radioimmunoassay, cortisol by competitive protein binding assay, catecholamines by radio-enzymology and glucose by colorimetry (glucose oxydase). In calves born spontaneously at term, the insulin injection induced a significant rise in plasma ACTH and cortisol concentrations on day 5 after birth; this rise occurred on days 10 and 30 after birth in calves delivered on day 260 of gestation. The rise in plasma insulin concentration following insulin injection was always more pronounced and sustained in calves delivered before term than in those born spontaneously at term. Following insulin injection, plasma epinephrine concentration increased significantly only on day 30 in calves born spontaneously at term. After treatment, no other change in plasma catecholamine concentrations was observed in any group of calves at any age. These results indicate that the pituitary-adrenal axis responded similarly in 5-day old calves born spontaneously at term and in 10 (or 30)-day old calves delivered by caesarean section 18 days before the expected time of parturition.
It was studied whether the beta-receptor stimulating fenoterol had any influence on endogenous catecholamines in the lung tissue of fetuses. On the 23rd, 27th and 31st days of pregnancy, concentrations of noradrenaline and dopamine in the lung homogenate of mature and immature rabbit fetuses were determined by fluorometry, and the basic surfactant components total phospholipids and lecithin by colorimetry, in a group receiving beta-mimetic treatment and in a control group receiving physiological salt solution. The concentration of noradrenaline decreased with the progression of pregnancy but the concentration of dopamine did not change significantly. Application of fenoterol caused an increase in total phospholipids and lecithin in the lungs of 23 and 27 day old rabbit fetuses and decreased the concentration of catecholamines, especially of noradrenaline. The drug had no such effect in mature (31 day) fetuses.
Colorimetry was used to assay blood copper levels in 13 asbestosis patients (mean age 55.5) selected by excluding all cases with an evident clinical anamnesis of dietary imbalances or other significant pathologies. The results show increased blood copper in 11 out of 13 patients, the mean level in this group being significantly higher than that in a control group (p less than 0.01). The phenomenon, already described in other interstitial lung diseases, may well be attributable to enhanced reabsorption of the metal due to the intensified activity of a copper enzyme lysyl oxidase that is involved in collagen synthesis.
The thiobarbituric acid (TBA) reaction, quantified by colorimetry or fluorimetry, is the method most widely used for studying lipid peroxidation in both laboratory animals and in humans with disorders. However, concerns regarding its analytical specificity have often been expressed, because TBA reacts with a wide variety of chemical species to produce a pink to red color. In this study, we reacted TBA with various saturated and unsaturated aldehydes (both directly and in the presence of sucrose, fructose, and glucose), substituted pyrimidines, 2-deoxyribose, and N-acetylneuraminic acid. We also studied the TBA reaction with bilirubin, biliverdin, icteric serum, and serum containing hemolyzed erythrocytes, comparing the absorption spectra of these reaction products with that for malondialdehyde (MDA). The reaction products were also analyzed for MDA by high-performance liquid chromatography (HPLC). Although the TBA reaction with some of these compounds may not be important in biological studies, others could lead to misinterpretations of increased lipid peroxidation. Use of HPLC to quantify MDA is recommended because of its high analytical sensitivity and specificity, especially in the study of lipid peroxidation in human subjects.
Ten patients with severe palmo-plantar hyperhidrosis have been treated successfully at home with tap water iontophoresis for a period not less than 6 months. The patients were asked to evaluate the treatment subjectively; 8 considered the results to have been good to very good. The same results were obtained in an objective evaluation by gravimetry, hygrometry and colorimetry. The full effects were seen after an average of 15 treatments of 20-30 min each. Through the new possibility of treating patients at home, therapy for palmo-plantar hyperhidrosis, which to date was only possible under medical supervision, has been simplified.
A gas chromatographic (GC) method for determination of supplemental alpha-tocopheryl acetate in high potency vitamin E powders and oils was collaboratively studied as an alternative to the AOAC colorimetric method (43.147-43.151, Emmerie-Engel), which requires saponification, extraction of the saponifiable fraction, and quantitation by colorimetry. The simpler GC procedure requires only extraction and/or enzymatic digestion and dilution before quantitation. Six blind duplicates were distributed to 10 laboratories; all 10 returned results. Repeatability (sr) and reproducibility (sR), % vitamin E/g, for the feed oil concentrates was 1.1 and 1.3, respectively; for the feed adsorbates 1.0 and 1.5; and for the spray-formulated powders 1.4 and 1.3. These results compare favorably with results obtained in a comparison study of the GC and Emmerie-Engel methods conducted by BASF in 1985. The method has been approved interim official first action for determination of alpha-tocopheryl acetate in vitamin E acetate concentrates as an alternative for those products only to AOAC colorimetric method 43.147-43.151.
Six crown and bridge alloys ranging in nobility between 25-63 wt % (18-45 at %) were analyzed by optical microscopy, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and secondary ion mass spectroscopy (SIMS), as well as by L*a*b* colorimetry before and after in vitro tarnishing in artificial saliva with and without additions of 0.00016, 0.016, and 1.6 % Na2S with a rotating wheel apparatus. All alloys except the lowest of 18 at % changed colors to about the same degree after 72 h of tarnishing. All alloys decreased in L*, while increased in both a* and b*, thus appearing darker and with increased redness and yellowness. This was due to localized darkening and to other products. For all alloys except one, saliva without sulfide promoted color changes more severe than for saliva with 0.016 % Na2S. For the most part, analysis by EDS was unable to detect differences between the tarnished films and the as-polished surfaces. SIMS analysis, however, showed changes in the substrate ion (Cu, Ag, Pd, and In) peak intensities. In most cases the intensities decreased and with the decrease greater with the sulfide-free saliva than with sulfide-containing. This indicated that sulfide promoted insoluble deposition of products. Changes in the Ag, Pd, and In peak intensities followed much the same pattern as with Cu. The as-polished surfaces, even though carefully prepared, showed much contamination in the form of organics, namely C, CH, N, NH, O, CHN, CN, as well as from Na, K, Ca, Si, S, Cl, and others. Most tarnished surfaces showed large increases in Na, K, and Ca, and with the sulfide-free saliva being more severe in this regard. The mass spectrum also showed peaks with atomic mass units in the range 55-58 related to only some of the tarnished surfaces.
Sodium, potassium and chloride stool content was studied in 107 children aged 1 to 32 months (11 +/- 8 months) presenting with acute diarrhea related to a rotavirus infection (34 cases), to an invasive pathogen (Salmonella or Shigella 14 cases, E. coli 4 cases), or of non-identified etiology (65 cases). The therapeutic protocol was the same in all cases: rehydration for the first 24 hours, progressive realimentation from the second or third day, no drugs being given. An average of 4 stools were analysed for each child (range 2-14), the fecal samples being collected over 2 to 4 consecutive days. Na+ and K+ (n = 366) were assayed by flame photometry and chloride (n = 88) by continuous colorimetry. In the stool samples taken as a whole, without taking into account etiology or day of sampling, the electrolyte concentration (mean +/- SD) was 42 +/- 20 mmol/l for Na+ (range 4-166), 51 +/- 24 mmol/l for K+ (range 5-195), and 24 +/- 11 mmol/l for Cl- (range 4-93). No significant variation of these values was observed according to etiology, duration, severity of the diarrheal syndrome, oral rehydration or nutrition.
Several studies have been performed to examine the problem of diagnosing gastroduodenal reflux (GDR). No single method is widely accepted. The aim of this work was to evaluate the diagnostic value of gastric pHmetry in this regard. A gastric aspiration probe attached to a combined glass electrode was placed in the stomach of 24 patients, with its distal tip located between 9 and 12 cm below the cardia. One ml samples of gastric juice were taken from 8 of the patients every 30 min for 15 h and as well as, every time a spontaneous alkalinization (SA) (defined by a pH greater than or equal to 4 for at least 1 min) was observed. The pH of each sample was measured by colorimetry whereas the concentration of total biliary acids (CTBA) was evaluated by the fluorimetric method (Kit Sterognost 3 alpha Flu); pH value measured via the intragastric electrode during aspiration was also recorded (protocol A). Continuous gastric aspiration was carried out in the remaining 16 patients for the entire duration of the test (6 h) which was divided into periods of 20 min. Apart from the parameters evaluated during protocol A, the percentage of time during which the stomach had a pH greater than or equal to 4 was recorded, as well as the quantity of total biliary acids collected over the 20 min periods (protocol B). Correlation studies were carried out using the Kendall tau and Spearman tests. Percentages were compared using the chi 2 test.(ABSTRACT TRUNCATED AT 250 WORDS)
The polymorphic behavior of symmetric diacid triacylglycerols (TGs), 1,3-dioleoyl-2-stearoyl (OSO), 2-elaidoyl (OEO), and 2-vaccinoyl (OVO) glycerols were studied by differential scanning colorimetry (DSC) and X-ray diffraction and compared with the corresponding monoacid TGs triolein (OOO), tristearin (SSS), trielaidin (EEE), and trivaccinin (VVV). The monoacid TGs formed a bilayered structure in all the polymorphic forms. On quenching from the melt, the diacid TGs OEO and OVO formed a bilayered (D = 45 A) beta'-phase with the exception of OSO, which formed a hexagonally packed bilayered (D = 52 A) alpha-phase. At -7 degrees C, the alpha-phase of OSO quickly transformed to a bilayered (D = 45 A) beta'-phase. Incubation at the beta'-phase melting temperature transformed OVO, OEO, and OSO into a trilayered (D = 65 A) beta-phase, where the 1,3-dioleoyl chains are segregated from the vaccinoyl, elaidoyl, or stearoyl chains into alternating layers. In summary, when all the acyl chains in a TG are the same (saturated, cis or trans unsaturated), the stable beta-phase packs into a bilayered structure. However, when the 1- and 3-acyl chains are cis unsaturated (bent) and the 2-acyl chain is either saturated or trans-unsaturated (straight), a bilayered beta'-phase can form, but transforms to a stable trilayered beta-phase, where the 2-acyl chains form a layer between two different layers of 1,3-oleoyl chains.
A procedure is developed, involving electrophoresis and TCA-ethanol treatment of electrophoregramms, which enabled to estimate quantitatively the modified derivatives of albumin just in blood serum without the protein isolation. The method is based on ability of native albumin to maintain its solubility after TCA-ethanol treatment. At the same time, modified albumin with conformational alterations was fixed on a carrier and might be estimated using colorimetry or densitometry. The procedure developed might be used in chemical industry for evaluation of toxic effects of some substances.
A total of 194 clinically healthy children 11 +/- 1.5 years of age were studied during different seasons. Systolic and diastolic blood pressure were determined by auscultatory endpoints, and blood and urine were collected at 4-hr intervals over a 24-hr span. Urinary norepinephrine, epinephrine, and dopamine were determined by HPLC, plasma aldosterone by RIA, serum sodium and potassium by ion-specific electrode, and calcium and magnesium by colorimetry. The circadian means showed statistically significant circannual variations in all variables except epinephrine. The highest circadian means of systolic and diastolic blood pressure and of urinary norepinephrine occurred during winter; the highest values of plasma aldosterone, serum potassium, and urinary dopamine were found in fall, those of serum calcium and magnesium during the summer, and that of serum sodium in spring. Circannual rhythms characterize functions related to blood pressure regulation in children. The circannual elevation of blood pressure (within the usual range) and of norepinephrine were both found to occur in winter. This time relation may have a functional significance, although a causal relationship is not proven by the temporal coincidence of two rhythms.
The determination of the vitamin A concentration in fortified milk was compared using Carr-Price analysis and liquid chromatography (LC). Carr-Price analysis required saponification of the sample with alcoholic potassium hydroxide, extraction with ether, and colorimetry with antimony trichloride in chloroform. LC analysis required hexane extraction of a 71% alcohol-sample solution and centrifugation at 2000 rpm. A 100 microL aliquot of the extract was analyzed on a LiChrosorb Si-60, 5 micron column, using an ethyl ether-hexane (2 + 98) mobile phase and detection at 313 nm. Each method was statistically evaluated for precision and sample-to-sample reproducibility. The LC extraction procedure was examined for efficiency. Each LC value was divided by the Carr-Price value obtained for the same sample; an average value of 0.975 with a coefficient of variation of 6.90% was obtained. It was concluded that the procedures were statistically equivalent.
Of two sensitive complexometric reagents for the colorimetry of serum zinc that we investigated, one, 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol (Br-PADAP), was found to be a potentially useful compound for trace-metal determinations. It has a high molar absorptivity (120 000 L mol-1 cm-1) but is not convenient to use because it is not very soluble in water. The other reagent, a related pyridylazo compound, is 2-(5-bromo-2-pyridylazo)-5-(N-n-propyl-N-3-sulfopropylamino)phenol (5-BR-PAPS). It seems better suited for use in routine zinc determinations because, besides being water soluble, it has a higher molar absorptivity, 130 000 L mol-1 cm-1. Results by the proposed method developed with 5-Br-PAPS correlated well with those by atomic absorption spectrophotometry. The between-run CV for control sera was less than 5%; the within-run CV (same controls) was less than 4%.
In this study plasma levels of vitamin A, carotenoids, retinol binding protein (RBP), prealbumin (PA), HDL-and total cholesterol were determined in 19 female subjects with cervical dysplasia and compared to those of the healthy female subjects described in our previous research. Plasma levels of vitamin A and carotene were determined by a spectrophotometric method using trifluoroacetic acid, plasma RBP and PA by single radial immunodiffusion and HDL- and total cholesterol by enzymatic colorimetry. Plasma mean values of vitamin A and HDL-cholesterol were lower (P less than 0.05 and P less than 0.01, respectively) than in the control group. On the contrary total cholesterol was higher (P less than 0.01) in the patients than in the control group. Vitamin A plasma levels were significantly related (P less than 0.01) to RBP and PA. No significant statistical correlation was found between the severity of the dysplasia and vitamin A plasma levels.
In this study plasma levels of vitamin A, carotenoids, retinol binding protein (RBP), prealbumin (PA), HDL-and total cholesterol of 40 subjects with carcinoma of cervix uteri were determined and compared to those of the healthy female subjects described in our previous research. Plasma levels of vitamin A and carotene were determined by a spectrophotometric method using trifluoroacetic acid, plasma RBP and PA by single radial immunodiffusion, and HDL-and total cholesterol by enzymatic colorimetry. Plasma mean values of carotene, vitamin A, RBP and HDL-cholesterol were lower (P less than 0.01) than in the control group, and the same applies to the PA mean plasma level (P less than 0.05). On the contrary, total cholesterol mean value of the patients resulted to be higher (P less than 0.01) than in the control group. Vitamin A plasma levels were significantly related (P less than 0.01) to RBP and PA. No significant statistical correlation was found between the clinical stage and the histological grading and vitamin A plasma levels.