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At least 1,423 records · Page 79Linked to original sources
PubMed1998

[Detection of 17-ketosteroid and 17-hydroxycorticosteroid in urine after separation and collection by foam rubber].

Using foam rubber 17-ketosteroid (17-KS) and 17-hydroxycorticosteroid (17-OHCS) were separated and collected in urine. 17-KS and 17-OHCS were eluted down from the foam rubber with alcohol, colour reaction can be respectively produced by m-dinitrobenzene and phenyhydrazine hydrocholoride, then both of them were detected by spectro-photometry. The standard deviation of this method was +/- 0.032, and its minimum detectable concentration was 0.01 microgram.ml-1. The recovery rate of 17-KS and 17-OHCS estimation was from 99.0% to 101.0%, with co-efficients of variation less than 6.23%.

17-Hydroxycorticosteroids↗
PubMed1998

[A study of immobilized enzyme-assisted semisynthesis of human insulin].

In this paper, a study on preparation of human insulin by immobilized enzyme-assisted semisynthesis is reported for the first time in our country. Porcine insulin with Thr(Bu(t)OB(t) catalyzed by immobilized trypsin has been converted into human insulin via a two-step transpeptidation. With the systematic technique of optimization, the rate of transpeptidation is 66%-70%. PAGE photometry is used to determine the conversion rate of semisynthesis. PAGE and C-terminal analysis of protein are adopted to identify the semisynthesis human insulin.

Enzymes, Immobilized↗
PubMed1999

[Bone marrow involvement in ovarian cancer by immunohistochemical assessment].

In the study below we introduced certain conclusions from bone marrow analysis in patient with ovarian cancer in the presence of epithelial cells. The study included cytological bone marrow slides taken from 31 patients. We analyzed the cellular antigen expression using immuno-histological chemistry technic with NCL-CA 125, NCL-EMA and NCL-C11 antibodies. In the material drived from 3 patients with advanced neoplastic changes, we detected the presence of cells that were stained positively. In order to define the actual frequency of cell presence with tested antigen expression in bone marrow as well as to signify the diagnostic and prognostic value of their detection requires a larger study group as well as using other examination technics such as PCR or transluscent photometry.

Adult↗
PubMed1999

Insulin resistance and urinary excretion of sodium in hypertensive patients with non-insulin dependent diabetes mellitus.

BACKGROUND: Hyperinsulinemia has been implicated in the pathogenesis of hypertension both in non-diabetic and diabetic patients. A causal relationship between renal sodium retention and hyperinsulinemia is speculated to play role in the development of hypertension in diabetes mellitus. MATERIAL AND METHODS: Twenty patients (12 males; 8 females) with hypertension and non-insulin dependent diabetes mellitus (NIDDM) and twenty normotensive patients (11 males, 9 females) with NIDDM were included in the present study. Blood samples for glucose and immunoreactive insulin (IRI) assay were collected at 0, 30, 60 and 120 minutes after 75 g of glucose per oral. Urinary sodium excretion in 24 hrs was estimated by flame photometry. Insulin response to glucose and correlation between basal insulin secretion and urinary sodium excretion were evaluated. RESULTS: Mean fasting plasma glucose value was significantly raised in hypertensive group in comparison with normotensive group of diabetic patients. Patients with diabetes and hypertension and significantly higher level of serum IRI than normotensive patients with diabetes mellitus. Urinary sodium excretion was significantly lower in diabetic patients with hypertension than in diabetic patients without hypertension. A negative correlation between basal insulin level and urinary Na+ excretion was observed in hypertensive patients with NIDDM. CONCLUSION: A negative correlation between hyperinsulinemia and 24 hrs urinary Na+ excretion was observed in patients with diabetes and hypertension. The study highlights that patients with diabetes mellitus have tendency to retain sodium under the influence of insulin but this needs further evaluation.

Blood Glucose↗
PubMed2000

Methods of calculating lung delivery and deposition of aerosol particles.

Lung deposition of aerosol is measured by a variety of methods. Total lung deposition can be measured by monitoring inhaled and exhaled aerosols in situ by laser photometry or by collecting the aerosols on filters. The measurements can be performed accurately for stable monodisperse aerosols. However, for polydisperse and/or unstable hygroscopic aerosols, measurement methods are limited and often unreliable. Regional deposition is assessed primarily by gamma scintigraphy. The scintigraphic method is useful for a general description of deposition patterns, but may not be adequate for quantitative regional dose estimation. New emerging three-dimensional lung imaging methods such as SPECT and PET, and innovative bolus aerosol delivery methods, have great potential for measuring detailed regional deposition. An accurate assessment of regional lung dose is difficult to achieve by the current methods. A multi-prong approach may be needed, with various methods and techniques, both in theory and experiment, to measure site-specific deposition dose.

Aerosols↗
PubMed2000

[Role of red blood cell changes in chronic occlusion of low limb arteries].

To study morphofunctional status of red blood cells, peripheral blood was investigated in 49 patients with chronic occlusions of low limb arteries (COLLA) and 23 healthy donors matched by gender and age. Circulation in the limbs was assessed by infrared thermography. Photometry provided data on microrheological properties of blood by reversible red cell aggregation. Scanning electron microscopy examined superficial red cell architectonics. The findings evidence that red cell aggregation in COLLA patients enhances irrespective of the ischemia degree while dysaggregation declines, polymorphism of red cell polymorphism grows with an increase of the number of transformed cells varying by degeneration stage. The above changes in red cell microrheology contribute to impairment of microcirculatory perfusion and tissue hypoxia in COLLA patients.

Aged↗
PubMed2000

Low dose gossypol for male contraception.

AIM: To ascertain whether the side effects of gossypol, hypokalemia and irreversibility, could be avoided on dose reduction. METHODS: Seventy-seven male volunteers were divided into 3 groups: control (22 cases), 10 mg gossypol (29 cases) and 12.5 mg (26 cases). Serum levels of testosterone, FSH and LH were measured by RIA and potassium by flame photometry. Sperm counts and motility were examined before and regularly after treatment for the evaluation of contraceptive efficacy. RESULTS: The average sperm density and motility started to decrease significantly by the end of month 2 of medication and gradually reached the infertility levels (< 4 million/mL) in both treated groups. After that the 10 mg group was asked to take the same dose every other day for up to a total observation period of 16-18 months for the maintenance of infertility. Subjects in the 12.5 mg group did not take gossypol any more so as to observe the length of the loading dose required, but in a few, a maintenance dose of 12.5 mg every other day was instituted for a few more months. In both treated groups, none of the spouses was pregnant during the maintenance dose period. Serum levels of potassium, FSH, LH and testosterone were not significantly changed and not a single volunteer complained of myoasthenia. After cessation of drug administration, the semen data returned to pretreatment levels. CONCLUSION: A regimen with 10 or 12.5 mg of gossypol as the daily loading dose and 35 or 43.75 mg as the weekly maintenance dose could induce infertility in male volunteers without developing hypokalemia or irreversibility.

Contraceptive Agents, Male↗
PubMed2000

Inductively coupled plasma emission spectroscopic and flame photometric analysis of goat epididymal fluid.

AIM: The elemental composition of the epididymal luminal fluid (ELF) in adult goat (Capra indica) was investigated. METHODS: ELF was collected by micropuncture from twelve sites along the epididymal duct. The elemental contents was analyzed with inductively coupled plasma (ICP) emission spectroscopy, a microanalytical technique that can simultaneously measure many elements in minute volumes of sample. The Na and K concentrations were determined by flame photometry. RESULTS: ICP spectroscopy showed the presence of copper, calcium, nickel, iron, magnesium, chromium, titanium and zinc in ELF, with fluctuating levels at different sites along the length of the epididymis. Cadmium, cobalt, lead and manganese were not found. The Na+/K+ ratio was seen to be higher at the initial segments of the epididymis and lower at the distal. CONCLUSION: It is proposed that the observed characteristic distribution of elements in ELF may have far reaching implications in sperm maturation and storage known to occur in the epididymis.

Animals↗
PubMed1989

[Alternative methods to animal experimentation lead to the discovery of a novel inflammation factor]

Simple testing models have been developed for the evaluation of chemical or biological compounds that influence the activity of leukocytes. Human blood neutrophil leukocytes are used. They are stimulated in various ways, and the effects of test compounds on the release of enzymes, the generation of oxygen radicals and cell damage are quantified. All assays are performed in microtiter plates and the responses are evaluated by multi-well photometry or fluorimetry. The models are apt to detect compounds acting on leukocytes as stimuli, inhibitors, and response modifiers. The use of these methods led to the discovery of a novel inflammatory peptide, NAP-1, which activates neutrophil leukocytes. NAP-1 consists of 72 amino acids and is generated by a variety of tissue cells.

Journal Article↗
PubMedDate not supplied

Influence of dehydroepiandrosterone on platelet aggregation, superoxide dismutase activity and serum lipid peroxide concentrations in rabbits with induced hypercholesterolemia.

UNLABELLED: Special interest in the role of DHEA dates back to the finding of a correlation between low serum DHEA concentrations and a higher morbidity and mortality rate due to coronary diseases in humans. Animal studies with experimental atherosclerosis confirmed the anti-sclerotic effect of DHEA. The mechanism of DHEA action remains unclear. We determined the influence of dehydroepiandrosterone (DHEA) administration, a potential anti-atherogenic agent, on platelet aggregation, platelet superoxide dismutase (SOD) activity and serum lipid peroxide (LPO) levels in male rabbits fed on a normal and atherogenic diet. 44 adult male New Zealand white rabbits were divided into 4 groups: 1--control group fed on standard rabbit food, 2--fed on an atherogenic diet, 3--fed on an atherogenic diet with DHEA, 4--fed on standard food with DHEA. We detected blood platelet aggregation following (ADP) and collagen activation by means of photometry. Platelet SOD activity was detected by means of fluorometry determining the inhibition of adrenaline auto-oxidation. The serum LPO concentration was measured by means of the colorimetric method. The serum DHEA-S concentration was measured by means of RIA methods, and serum lipid levels were measured by means of Biomérieux manufactured kits. Results demonstrate that (1) elevated LPO concentrations in rabbits with hyperlipidemia did not decrease following DHEA administration. (2) In rabbits fed on a normal diet, DHEA caused a decrease of LPO, which emphasizes the positive influence of this steroid on the oxidative stress in healthy animals. Such a result was not seen in the group with severe hyperlipidemia. (3) Rabbits with hyperlipidemia demonstrated a significantly decreased SOD activity. (4) In healthy animals as well as in those with hyperlipidemia, DHEA administration caused an increase of platelet SOD activity, the main enzyme of the antioxidant defence system, which protects the organism against free radical damage (5) (DHEA had no influence on platelets aggregation in both tested groups). IN CONCLUSION: DHEA administration improves platelet SOD activity, which protects cells against oxidative damage. The hypothesis that DHEA administration leads to an increase in antioxidant potency requires further investigations.

Adenosine Diphosphate↗
PubMed2000

Dynamics of potassium and nitrate ions release from polycarboxylate cement with 5% KNO3.

Release of potassium and nitrate ions from polycarboxylate-cement blocks containing 5% KNO3, with different exposure in extragent aqua redestillata was studied. Using flame photometry we found increased concentration of eliminated potassium ions into the extragent after the 24th hour (0.90 +/- 0.03 mg/cm3) while the maximum quantity of released potassium ions was measured after the 14th day (336 h)--1.50 +/- 0.02 mg/cm3 (t = 60, P < 0.001). The concentration of the released nitrate ions was determined by spectrophotometry at l = 410 nm. The degree of extraction of nitrate ions from the model cement blocks progressively increased with time, but their concentration in the cement decreased after the 14th day too, demonstrating a statistically significant difference: from 4.50 mg on the 20th minute to 2.60 mg on the 14th day (t = 115, P < 0.001).

Humans↗
PubMed2001

[Measurement of lead in high-salt food with sulfuric-nitric acid to treat food ash].

Lead in high-salt food was measured by treating the ash with sulfuric-nitric acid, and diluting lead standard with sodium sulfate to eliminate the disturbance of chloride in detecting lead with atomic absorption spectrophotometry. The minimum detection limit was 0.10 mg/kg. The relative standard deviation is 1.72%, 5.00% and 7.14% while the amount of lead was 8.70, 2.40 and 1.40 micrograms respectively. The recovery varied between 90.0%-109.0%. There was no significant difference (P > 0.05) of the lead content between the mentioned method and extraction flame photometry. The amount of lead is higher obviously than that of other two methods by eliminating the disturbance of chloride. The method was simple, precise and accurate, and suitable for hygienic examination.

Food Contamination↗
PubMed2001

Thermal diversities of two Na+/H+ exchanges in guinea pig red cells.

OBJECTIVE: To test the effect of hypothermia on Na+/H+ exchange, activated by shrinkage and cytoplasmic acidosis. METHOD: Amiloride-sensitive Na+ influx in guinea pig red cells was traced with isotope 22Na and intracellular Na+ concentration was measured by emission flame photometry. RESULT: Amiloride-sensitive Na+ influx decreased linearly as a function of temperatures (about 37 degrees C) in shrunken cells, but increased in acidified cells. The up-regulation of acid-induced Na+/H+ exchange by elevated temperature was enhanced by hypo-osmolarity. Less sensitivity of intracellular H+ site at 41 degrees C may be the mechanism for the inhibition of shrinkage-induced Na+/H+ exchange by elevated temperature. Heating-mediated explosive increase in the activity of acid-induced Na+/H+ exchange may be due to enhanced extracellular Na+ sensitivity and lower intracellular pH caused by acidic metabolites. Acid-induced Na+/H+ exchange contributes to cytoplasmic Na+ accumulation. CONCLUSION: These two modes of Na+/H+ exchange with different response to elevated temperature may play different roles in the cellular pathogenesis of heatstroke.

Animals↗
PubMed1975

A review of bromine determination in foods.

Organic compounds containing bromine, including methyl bromide, ethylene dibromide, and 1,2-dibromo-3-chloropropane, have been used extensively for the fumigation of foods, or soils in which foods grow, making it necessary to determine residues of bromine and bromine-containing organic compounds. A large number of methods for the determination of bromine in foods, as organic, inorganic, and combined total bromide, have been developed. In methods for organic bromide, the bromine is converted to the inorganic form for measurement by titration, photometry, or other means. In recent years, instrumental methods have been developed in which the total bromine in the sample is determined, regardless of the state in which it exists. X-ray fluorescence and neutron activation analysis are the 2 instrumental methods used most widely. Residue data are presented for some typical bromine-containing samples.

Activation Analysis↗
PubMedDate not supplied

[Distribution of organophosphate pesticides in two artificial plasmas: FSB-FSP].

Here is an attempt to establish that a close relation exists between the chemical formulae of organophosphates and their affinities for lipids, proteins and water. We carried out this study on two systems similar to human plasma. First, each component was sorted, then the organophosphates were detected and titrated by gas chromatography with flame photometry detector. Thiophosphates had a greater affinity for lipids than phosphates. Fixation of proteins was only observed on three hydrophilous organophosphates: phosphamidon, dichlorvos, ciodrin.

Chemical Phenomena↗
PubMed1999

[Changes of transmembrane ion transport in essential hypertensives with familial histories].

OBJECTIVE: To investigate the effects of heredity on transmembrane ion transport in essential hypertension (EH). METHODS: 52 essential hypertensives were divided into two groups, 23 with positive family history (FH(+)) and 29 with negative family history (FH(-)). The rate constant of ouabain-sensitive sodium efflux ((o)K(os)) was measured as the half of the increase in erythrocyte Na(+) concentration during incubation with ouabain for 2 hours, (o)K(os) was calculated by an equation and the maximal rate (Vmax) of red cells Na(+)/H(+) exchange was determined as the Na(+) influx promoted by an outward H(+) gradient. Intracellular Na(+) concentration was measured with flame photometry and (45)Ca(2+) influx in ATP-depleted red cells with liquid scintillation counting. RESULTS: The red cell Na(+)/H(+) exchange and (45)Ca(2+) in-flux were significantly higher but the (o)K(os) lower in both the FH(+) and FH(-) groups than in the controls. FH(+) group demonstrated a significantly higher (o)K(os) and lower Ca(2+) influx as compared with those in FH(-) group. In FH(+) group, systolic blood pressure was positively correlated with age, while diastolic blood pressure positively correlated with (45)Ca(2+) influx. CONCLUSION: Our data show a genetic contribution to abnormal membrane transport in hypertension. There is a defect in membrane permeability to Ca(2+) and a greater exchangeable pool of cytosolic free Ca(2+) in FH(+) group that participate in the pathogenesis of inherited hypertension.

Aged↗
PubMedDate not supplied

Metabolic effects of alcoholism and its relationship with alcoholic liver disease.

BACKGROUND: Chronic and excessive ethanol consumption is associated with cellular proliferation, fibrosis, cirrhosis and cancer of liver. It was planned to study the effect of alcohol on different biochemical parameters as distribution of these parameters may lead to several complications in gastrointestinal tract, liver, kidney, brain etc. METHODS: 50 alcoholic males and 20 normal subject (with no history of alcohol) with an age ranges 30-45 years were included in the study. Biochemical parameters related to liver were estimated by standard kit. Besides, ions and electrolytes were also determined by standard kit and flame photometry. RESULTS: It was observed that level of alkaline phosphatase, alanine transferase, protein and globulin were significantly increased as compared to normal subjects. Besides, ions like calcium and phosphate were significantly decreased. On the other hand the level of potassium and magnesium was significantly decreased as compared to normal subjects. Electrophoresis shows a protein of 100 Kda is present in the patients sample as compared to control subjects. CONCLUSION: It is therefore concluded that abnormal biochemical function of liver in alcoholism can lead to several complications, hence further research is needed to reach a definite conclusion.

Adult↗