Changes in haematological parameters and iron metabolism associated with a 1600 kilometre ultramarathon. (1/3524)

OBJECTIVE: To investigate haematological variations and iron related changes in the serum of participants in a 1600 kilometre ultramarathon run. PARTICIPANTS: Seven male and two female participants in a 1600 km foot race. METHODS: Blood samples were obtained from the participants before, after four and 11 days of running, and at the end of the event. Samples were analysed by standard methods for haemoglobin, packed cell volume, total red cell count, mean red cell volume, mean red cell haemoglobin, total white cell count and differential, platelets, reticulocytes, iron, ferritin, total iron binding capacity, percentage transferrin saturation, haptoglobin, and bilirubin and corrected for changes in plasma volume. RESULTS: The following variables decreased during the event (p < 0.05): haemoglobin, packed cell volume, mean red cell volume, percentage lymphocytes, percentage monocytes, serum iron, total iron binding capacity, and percentage transferrin saturation. Increases (p < 0.05) were found in plasma volume, total red cell count (day 4 only), total white cell count, percentage and absolute numbers of neutrophils and reticulocytes, absolute numbers of lymphocytes and monocytes (day 4 only), absolute numbers of eosinophils (day 11 and race end), absolute numbers of basophils (race end only), platelets, ferritin, haptoglobin, and bilirubin (day 4 only). CONCLUSION: Ultramarathon running is associated with a wide range of changes in haematological parameters, many of which are related to the normal acute phase response to injury. These should not be confused with indicators of disease.  (+info)

Improved methods using the reverse transcriptase polymerase chain reaction to detect tumour cells. (2/3524)

Reverse transcriptase polymerase chain reaction (RT-PCR) is increasingly used to detect small numbers of circulating tumour cells, though the clinical benefit remains controversial. The largest single contributing factor to the controversy of its value is the different approaches to sample processing. The aim of this study was to compare the sensitivity and reproducibility of RT-PCR for the detection of tumour cells after four commonly used different methods of sample processing. Using RT-PCR, one tumour cell spiked in 2 ml of whole blood was detected after analysis of separated mononuclear cell RNA, whole blood total or poly-A+ RNA. No false positives were identified with any method. However, the reproducibility of tumour cell detection was reduced after isolation of the mononuclear cell fraction. Only analysis of poly-A+ RNA had a sensitivity of 100% in all the cell spiking experiments. In patient blood samples, analysis of poly-A+ RNA increased the number of blood samples positive for tyrosine hydroxylase (TH) mRNA compared with those positive after analysis of total RNA. This may reflect high levels of cDNA reducing the efficiency of the PCR. Isolation of poly-A+ RNA increases the sensitivity and reproducibility of tumour cell detection in peripheral blood.  (+info)

Antioxidative activity of 4-oxy- and 4-hydroxy-nitroxides in tissues and erythrocytes from rats. (3/3524)

AIM: To compare the activities of antioxidation of 4-oxy- and 4-hydroxy-nitroxides in tissues and RBC from rats. METHODS: The homogenates of liver, heart, and kidneys of rats were used to determine malondialdehyde (MDA) formation using TBA colorimetric method. H2O2-caused hemolysis was measured spectrometrically. Superoxide anion from zymosan-stimulated neutrophils of rats was assayed by NBT reduction method. RESULTS: Nitroxide free radicals OTMPO and HTMPO inhibited MDA generation caused by .OH generation system (MIC 10.5 and 21 mumol.L-1, respectively), antagonized hemolysis induced by H2O2 (MIC: 338 and 168 mumol.L-1, respectively), but did not affect O2- formation from activated neutrophils. 1-Hydroxyl compounds OTMPOH and HTMPOH possessed similarly potent antilipoperoxidative activities. But nonfree radical OTMP and HTMP had no effect on peroxidation of tissues. CONCLUSION: Nitroxides exert their antilipoperoxidative effect by specifically scavenging .OH free radicals in biological system. Trapping of .OH free radicals by nitroxides is not by reduction of NO. group in nitroxides. Both NO. group and NOH group are essential active groups.  (+info)

Isolation and characterization of Vibrio parahaemolyticus causing infection in Iberian toothcarp Aphanius iberus. (4/3524)

High mortality among laboratory cultured Iberian toothcarp Aphanius iberus occurred in February 1997 in Valencia (Spain). The main signs of the disease were external haemorrhage and tail rot. Bacteria isolated from internal organs of infected fish were biochemically homogeneous and identified as Vibrio parahaemolyticus. The bacteria were haemolytic against erythrocytes from eel Anguilla anguilla, amberjack Seriola dumerili, toothcarp A. iberus and humans, and were Kanagawa-phenomenon-negative. Infectivity tests showed that the virulence for A. iberus was dependent on salinity. Finally, all strains were virulent for amberjack and eel.  (+info)

Hemolysis associated with 25% human albumin diluted with sterile water--United States, 1994-1998. (5/3524)

Since 1994, a shortage of 5% human albumin, a product used off-label during therapeutic plasma exchange (TPE), has existed in the United States. Because of this shortage, hospital pharmacists may prepare 5% solution of human albumin by diluting 25% human albumin with 0.9% NaCl or, when sodium load is a concern, 5% dextrose. However, if sterile water alone is used as the diluent, the osmolarity (tonicity) of the albumin solution is reduced and may cause hemolysis in recipients. This report describes two of 10 episodes of hemolysis (one fatal) among persons who received 25% human albumin diluted with sterile water and emphasizes that sterile water alone should not be used to dilute albumin.  (+info)

Novel techniques for in vivo hemolysis studies in guinea pigs. (6/3524)

The in vivo toxic-hemolytic studies using small experimental animals are complicated by difficulties in preventing hemolysis during repeated collection of blood specimens and in measuring hemoglobin concentration in small amounts of plasma sample. To solve these problems we tried to develope the new techniques for the in vivo hemolysis studies using guinea pigs. The hemolysis accident was minimized to 2.75 mg/dl by collecting the blood directly into heparinized microhematocrit tubes by small longitudinal incision in the auricular artery. The hemoglobin in a small amount of sample (10 microliters) was determined by the new analytical system using a microflow spectrophotometer with a modified cyanmethemoglobin method. The standard curve of the hemoglobin concentration in the system revealed a line of Y = 1.8X + 0.79 (r = 0.999), CV < 1% with a minimum detectable concentration of 1.25 mg/dl. By using the new techniques, it was found that the plasma hemoglobin concentration in normal animals were 7.27 +/- 0.44 mg/dl (mean +/- S.E.). The in vivo hemolytic activity of saponin was observed dose-dependently at doses of 30-50 mg/kg, i.v. in the guinea pigs. It is concluded that the present techniques are useful for in vivo hemolytic studies in small experimental animals such as guinea pigs.  (+info)

The hemolytic activity of bracken extracts in guinea pigs. (7/3524)

This study was conducted to elucidate the hemolytic activity of a new toxic substance in bracken fern. A crude extract (CE) was prepared from the methanol extracts of bracken by the column chromatography. When the CE was injected subcutaneously in guinea pigs, the hemoglobinuria and hemolysis were observed within 6 hr, and 3 days later edema and hemorrhages in the urinary bladder were observed. The CE was then fractionated by high performance liquid chromatography (HPLC), and three (HF, BF and CF) of the fractions showed the toxic activities in guinea pigs. The HF caused the hemolysis, whereas both the BF and the CF caused the hemorrhagic cystitis without any hemolytic activities. The HF was further fractionated by the HPLC, resulting of the 3 fractions (HF-I, II and III). The hemolysis was caused only with the HF-II, and HF-II as well as HF did not cause the hemorrhagic cystitis. HPLC analysis revealed that both BF and CF contains braxin B and braxin C, respectively, and both HF and HF-II do not contain braxin A, B or C. These facts suggest that bracken fern contains a new toxic substance (hemolysin) which induces the acute hemolysis in guinea pigs.  (+info)

The rgg gene of Streptococcus pyogenes NZ131 positively influences extracellular SPE B production. (8/3524)

Streptococcus pyogenes produces several extracellular proteins, including streptococcal erythrogenic toxin B (SPE B), also known as streptococcal pyrogenic exotoxin B and streptococcal proteinase. Several reports suggest that SPE B contributes to the virulence associated with S. pyogenes; however, little is known about its regulation. Nucleotide sequence data revealed the presence, upstream of the speB gene, of a gene, designated rgg, that was predicted to encode a polypeptide similar to previously described positive regulatory factors. The putative Rgg polypeptide of S. pyogenes NZ131 consisted of 280 amino acids and had a predicted molecular weight of 33,246. To assess the potential role of Rgg in the production of SPE B, the rgg gene was insertionally inactivated in S. pyogenes NZ131, which resulted in markedly decreased SPE B production, as determined both by immunoblotting and caseinolytic activity on agar plates. However, the production of other extracellular products, including streptolysin O, streptokinase, and DNase, was not affected. Complementation of the rgg mutant with an intact rgg gene copy in S. pyogenes NZ131 could restore SPE B production and confirmed that the rgg gene product is involved in the production of SPE B.  (+info)