Chemical composition of smoke produced by high-frequency electrosurgery.

BACKGROUND: Exposure to surgical smoke during electrosurgery may be harmful to theatre personnel. This study quantified toxic compounds present and we were particularly interested in isolating toluene, ethylbenzene and xylene due to their putative carcinogenic effects. METHODS: A variety of surgical procedures were studied. Smoke samples emitted during electrosurgery were collected in charcoal tubes and analysed by gas chromatography coupled with mass spectrometry. RESULTS: Surgery involving mainly thermal decomposition of adipose tissue produced greater quantities of aldehydes and lower concentrations of toluene. In contrast, smoke generated during epidermal tissue ablation produced higher levels of toluene, ethyl benzene and xylene. CONCLUSION: This study demonstrated the presence of irritant, carcinogenic and neurotoxic compounds in electrosurgical smoke. This may have considerable implications for the health and safety of all involved in surgical practice, as exposure to these compounds pose potential risks to health.

Characterization of certain inflammatory variables in the peripheral blood of clinically healthy dogs.

Many laboratory techniques have been developed to study and quantify the inflammatory response, including the release of acid hydrolase enzymes, leukotriene B(4) (LTB(4)) production, reactive oxygen species (ROS) production and complement conversion studies. Although extensively studied in human health and disease, the relevance of such tests in the dog is largely unknown. After isolation of the peripheral blood mononuclear cell (PBMC) and polymorphonuclear cell (PMN) fractions from the peripheral blood of 38 clinically healthy dogs, values for ROS production were similar for both cell fractions when measured by luminol-enhanced chemiluminescence (17,853+/-9,695 U/10(6) cells versus 19,138+/-14,569 U/10(6) cells for the PBMC (n=38) and PMN (n=18) fractions, respectively). However, the mean time taken to reach maximum chemiluminescence was noticeably shorter in the PBMC fraction (5.1+/-3.3 versus 10.7+/-2.5 min for PBMCs (n=36) and PMNs (n=18), respectively). Intracellular concentrations of beta-glucuronidase, beta-galactosidase and N-acetyl-beta-glucosaminidase were assayed by spectrofluorometry. Mean values for all three enzymes were higher in PBMCs (n=31-35) than in PMNs (n=10-14). Both cell fractions released 20% of the intracellular enzyme concentration when stimulated with opsonized zymosan. Following incubation with A23187 (1 microM), mean LTB(4) production was higher in PBMCs (4.45+/-2.92 ng/10(6) cells; n=27) than in PMNs (0.96+/-2.22 ng/10(6) cells; n=13) using a validated high performance liquid chromatography (HPLC) assay. Immunoprecipitation studies revealed that the mean percentage conversion of C3 to C3b following stimulation with opsonized zymosan was 57.3+/-13.4% (n=36). The results provide normal values for clinically healthy dogs that may subsequently be used in future studies investigating dogs with various inflammatory disorders.

Increased leukotriene B(4) production, complement C3 conversion and acid hydrolase enzyme concentrations in different leucocyte sub-populations of dogs with atopic dermatitis.

Various markers of the inflammatory response were measured in peripheral blood mononuclear cells (PBMCs) and polymorphonuclear neutrophils (PMNs) from 31 dogs with atopic dermatitis (AD). The variables assayed included chemiluminescence, acid hydrolase enzyme concentrations, leukotriene B(4) (LTB(4)) production and complement C3 conversion. The results were compared to those derived from a population of clinically healthy dogs. Dogs with AD exhibited a significant increase in median LTB(4) production in PMNs compared to controls (0.94 versus 0.00 ng/10(6) cells; P<0.01). Significant increases in the median concentrations of intracellular beta-galactosidase (PBMC fraction - 0.42 versus 0.25 mU/10(6) cells; P<0.05) (PMN fraction - 0.47 versus 0.12 mU/10(6) cells; P<0.01) and beta-glucuronidase (PBMC fraction - 0.52 versus 0.27 mU/10(6) cells; P<0.05) were also evident in the AD group. Although median maximum chemiluminescence values for both leucocyte sub-populations were higher in controls, the differences recorded were not significant (P>0.05). However, the median time taken to reach maximum chemiluminescence was significantly shorter in the PMN fraction of dogs with AD (7.00 versus 10.00 min; P<0.01). Atopic dogs had a significant increase in the median percentage conversion of complement C3 to C3b (66.0 versus 57.3%; P<0.01). The results of this study indicate a priming of the inflammatory response in dogs with AD. The role of LTB(4) in the pathogenesis of canine AD and the potential efficacy of leukotriene antagonists in the treatment of this disorder warrant further investigation.

Prevalence and public health significance of blemishes in cuts of Irish beef.

Between February 1999 and February 2000 more than 45,000 quarters of Irish beef cattle were examined for the presence of blemishes as they were cut into primal and subprimal cuts. A total of 2,379 blemishes, either scars or cysts, were found. Eight of the scars and one cyst tested positive for residues of inhibiting substances.

Neutrophil taurine in psoriasis.

Neutrophil taurine was measured in 30 subjects presenting with chronic stable plaque-type psoriasis. The taurine concentration expressed per 5 x 10(6) cells was significantly lower (p < 0.002) in these subjects compared to neutrophil taurine measured in 20 control subjects. In view of increasing evidence proposing possible roles for taurine in maintaining normal neutrophil function coupled with previously observed anti-inflammatory effects of taurine in vitro, an assessment of possible roles of taurine in the aetiology of psoriasis is discussed.

Determination of cimetidine in human plasma by high-performance liquid chromatography following liquid-liquid extraction.

A new method is described for the determination of cimetidine in human plasma. The drug and internal standard (ranitidine) were separated on a Nucleosil C18 5 microns (25 x 4.6 mm I.D.) column using a mobile phase of acetonitrile-phosphate buffer, pH 6.2 (25:75, v/v) containing 2.5 g/l heptane sulphonic acid. The mobile phase was delivered at a flow-rate of 0.9 ml/min, detection was by ultraviolet absorption at 228 nm and concentrations were calculated on the basis of peak areas. The drugs were extracted from alkaline plasma into ethyl acetate using a salting out procedure which involved the addition of 100 ml of a saturated solution of K2CO3 to each 250-microliters plasma aliquot. The method was validated over the concentration ranges 50-3000 ng/ml and 100-7000 ng/ml for two separate studies. Mean coefficients of variation were less than 6% for both intra- and inter-assay in both studies and recoveries varied between 71 and 81%. The method was successfully applied to the determination of cimetidine in plasma for a pharmacokinetic study.

Effects of in-vivo administration of taurine and HEPES on the inflammatory response in rats.

The effect of in-vivo administration of N-2-hydroxyethylpiperazine-N'-2- ethane sulphonic acid (HEPES) and taurine on rat paw oedema and reactive oxidant production was examined. Carrageenan-induced paw oedema was attenuated following intraperitoneal injection of HEPES. Chemiluminescence production by isolated peripheral blood mononuclear cells (PBMC) was reduced in HEPES-treated rats. Taurine-treated rats did not exhibit attenuation of paw oedema using subcutaneous or intraperitoneal administration but intracerebroventricular administration produced a significant reduction at a dosage of 4.0 mumol. No reduction in chemiluminescence production was observed by PBMC using subcutaneous or intraperitoneal administration of taurine, but intracerebroventricular administration produced a significant reduction at a dosage of both 0.4 and 4.0 mumol. Intravenous injection of [14C]HEPES or [3H]taurine demonstrated rapid clearance with a significantly longer half-life of HEPES compared with taurine. These results support previous reports of anti-inflammatory activity of taurine when administered centrally. The lack of anti-inflammatory effect when taurine was administered subcutaneously or intraperitoneally may be a consequence of rapid distribution or clearance. The greater anti-inflammatory effects of HEPES compared with taurine may be due to its slower distribution or clearance in-vivo.

Enhanced secretion of prostaglandin E2 by tissue-fixed macrophages in colonic carcinoma.

Prostaglandin E2 (PGE2) secretion by peripheral blood and tissue-fixed macrophages from patients with colorectal carcinoma was assessed. There was no significant difference between PGE2 production by peripheral blood mononuclear cells between patients with colorectal carcinoma and normal controls. However, secretion of PGE2 by tissue-fixed macrophages from within the colorectal carcinomata in response to opsonised zymosan was significantly higher than in the uninvolved colonic tissue. PGE2 production by tissue-fixed macrophages from within colonic polyps was found to be normal. These results could not be explained on the basis of increased availability of substrate arachidonic acid since addition of excess arachidonic acid resulted in similar findings. The enhanced production of PGE2 correlated with Dukes staging but not the level of differentiation. The production of PGE2 from epithelial cells in response to ionophore A23187 was not significantly enhanced. Leukotriene B4 secretion by intestinal macrophages in response to opsonised zymosan was not significantly elevated in the colonic tumour tissue. Modulation of levels of prostaglandin production within colonic tumours may play a role in the rate of growth and vascularity of these tumours and in the regulation of the local immune response to malignancy.

Enhanced chemiluminescence production by phagocytosing neutrophils in psoriasis.

Using serum-coated zymosan, the generation of reactive oxidants by measurement of chemiluminescence was shown to be significantly enhanced in isolated peripheral psoriatic neutrophils compared to normal controls. This response was observed irrespective of whether zymosan was opsonized with fresh autologous or normal AB serum. However, this increased activity was reduced with zymosan was opsonized with serum that was preheated at 56 degrees C for 30 min. There was no statistical correlation of chemiluminescence activity with degranulation of beta-glucuronidase in either normal or psoriatic subjects. In addition, chemiluminescence produced by normal cells was significantly increased when zymosan was opsonized with psoriatic serum. The plasma membrane-bound enzyme, NAD(P)H oxidase, which produces superoxide in response to phagocytic stimulation, was significantly increased in psoriatic neutrophils compared to normal controls. These data add further evidence for activated neutrophils in psoriasis.

Chronic granulomatous disease presenting as an oculomucocutaneous syndrome mimicking Behçet's syndrome.

A female patient who presented for the first time at the age of 19 with oculomucocutaneous syndrome was found to have an absolute deficiency of neutrophil peroxide production. Neutrophil peroxide production as measured by chemiluminescence was zero on stimulation with opsonized zymosan. Direct membrane stimulation with FMLP and calcium ionophore also failed to elicit peroxide production. The diagnosis of chronic granulomatous disease should be considered in young patients with oculomucocutaneous syndrome.

Effect of lithium therapy on inflammatory response.

Chemiluminescence produced by normal cells was reduced in response to zymosan which was opsonized with serum from patients on prophylactic lithium therapy, compared to control serum from normal subjects (68 +/- 3.1 vs. 93 +/- 3.4 mV/5 X 10(5) cells). Preincubation of normal cells with serum from patients also resulted in reduced chemiluminescence activity when the cells were stimulated with autologous serum-coated zymosan (47 +/- 4.5 vs. 64 +/- 6.3 mV/5 X 10(5) cells). Spontaneous complement conversion was increased in the serum of patients on lithium therapy (46.3 +/- 3.8 vs. 25.3 +/- 2.5% conversion). These studies demonstrated that lithium, at safe therapeutic levels (0.4-0.9 mmol/liter), significantly altered complement conversion and had a marked affect on chemiluminescence activity by normal cells.

Enhanced release of inflammatory mediators from lithium-stimulated neutrophils in psoriasis.

We have used lithium salts to stimulate degranulation in order to assess neutrophil activity in psoriasis. Evidence is presented for significant enhancement of degranulation of beta-glucuronidase (primary granules) and vitamin B12-binding protein (secondary granules) from lithium-stimulated neutrophils in psoriatic whole blood. Basal levels of granule markers showed no significant difference between normal and psoriatic neutrophils. On the other hand, enzymes associated with neutrophil function (myeloperoxidase and catalase) were found to be markedly increased in resting psoriatic neutrophils.

Influence of lithium and fluoride on degranulation from human neutrophils in vitro.

We have demonstrated that degranulation from normal human neutrophils in whole blood was stimulated by low concentrations of lithium salts and was produced by noncytolytic means. Significant amounts of beta-glucuronidase could be released from the primary granules, in addition to vitamin B12- binding protein from the secondary granules, by 10 mM lithium. Release was almost totally inhibited by 1 mM fluoride, under the same conditions. There was no release of lactate dehydrogenase and no loss of viability of cells incubated in either lithium or fluoride at the concentrations used. Lithium was also observed to have no effect on reactive oxygen production by phagocytic stimulation of isolated neutrophils. In addition, lithium and fluoride were shown to manipulate the intracellular levels of cAMP. The results demonstrated a direct effect of lithium on release of inflammatory mediators from neutrophils in vitro. The methods used also provide a simple and effective test to study an important function of neutrophil activity and can be used to evaluate degranulation in a number of clinical conditions.

Localization by immunofluorescence and by light- and electron-microscopic immunoperoxidase techniques of Tamm-Horsfall glycoprotein in adult hamster kidney.

1. Tamm-Horsfall glycoprotein was isolated from hamster urine and antiserum against it was produced in rabbits. Immunoglobulin G was isolated from the antiserum. 2. Indirect methods of immunofluorescence staining were applied to kidney sections previously fixed by both perfusion and immersion methods. Tamm-Horsfall glycoprotein was identified associated with only the cells of the ascending limb of the loop of Henle and the distal convoluted tubule. Maculae densae were free of the glycoprotein. 3. Indirect immunoperoxidase procedures with light microscopy were applied to kidney sections. The results extended those found by immunofluorescence by showing that the glycoprotein is largely associated with the plasma membrane of the cells. Macula densa cells were shown to be free of the glycoprotein, although the luminal surface of the remaining cells in the transverse section of the nephron at that region was shown to contain it. 4. A variety of immuno-electron-microscopic techniques were applied to sections previously fixed in a number of ways. Providing periodate/lysine/paraformaldehyde was used as the fixative, the glycoprotein was often seen to be present not only on the luminal surface of the cells of the thick ascending limb of the loop of Henle and of the distal convoluted tubule, but also on the basal plasma membrane, including the infoldings. 5. It is generally accepted that the hyperosmolarity in the medulla of the kidney results from passage of Cl(-) ions with their accompanying Na(+) ions across the single cell layer of the lumen of the thick ascending limb of the loop of Henle, a region of the nephron with relatively high impermeability to water. We suggest that Tamm-Horsfall glycoprotein operates as a barrier to decrease the passage of water molecules by trapping the latter at the membrane of the cells. Our hypothesis requires the glycoprotein on the basal plasma membrane also.

Analytical subcellular fractionation of guinea-pig myocardium.

1. Homogenates of guinea-pig left ventricle were fractionated by differential pelleting and by centrifugation on continuous sucrose density gradients. 2. The principal subcellular organelles of myocardium, characterized by their marker enzyme content, were resolved by density gradient centrifugation in a small-volume zonal rotor. The equilibrium densities (p) of the principal organelles are (with marker enzymes in parentheses): sarcolemma, 1-12 (5'-nucleotidase); lysosomes, 1-16 (N-acetyl-beta-glucosaminidase); mitochondria, 1-17 (cytochrome oxidase); peroxisomes, 1-18 (catalase); cytosol (lactate dehydrogenase). 3. The subcellular distribution of various adenosine triphosphatase activities and previously unassigned enzymes was determined. Leucyl-beta-naphthylamidase and gamma-glutamyl transpeptidase showed both cytosol and sarcolemma components. Ca2+-dependent adenosine triphosphatase showed dual localization to the mitochondria and to the sarcolemma.

Some factors affecting the production, by cultured baby-hamster kidney cells, of BHK glycoprotein I which cross-reacts immunologically with Tamm-Horsfall glycoprotein.

Cultured baby-hamster kidney cells (BHK-21/C13), which are adapted to grow in suspension (strain 2P), roduce a glycoprotein, termed BHK glycoprotein I, which cross-reacts immunologically with hamster urinary (Tamm-Horsfall glycoprotein. BHK glycoprotein I was isolated in an electrophoretically (sodium dodecyl sulphate/polyacrylamide gel) homogeneous form by application of affinity chromatography to the medium in which cells had been cultured. Insolubilized anti-(Tamm-Horsfall glycoprotein immunoglobulin G) was used as the adsorbent. The amount of BHK glycoprotein I associated with the cultured cells was found by both radioimmunoassay and immunofluorescence to be related to the amount of Ca2+ in the medium and to the particular stage of the cell cycle. 5'-Nucleotidase was also shed by the cells into the culture medium in amounts related to the stage of the cell cycle. The turnover of hamster Tamm-Horsfall glycoprotein in vivo appeared to be considerably more rapid than can be accounted for by cell turnover. Hamster Tamm-Horsfall glycoprotein was shown to be ineffective in inhibiting agglutination of chicken erythrocytes caused by influenza virus.

Studies on derivation of transcobalamin 3 from granulocytes. Enhancement by lithium and elimination by fluoride of in vitro increments in vitamin B12-binding capacity.

Unsaturated vitamin B(12)-binding capacity (UBBC) of human serum is not reproducibly measurable because it increases variably in vitro in relation to time, temperature, and, in the case of plasma, anticoagulant present before removal of cells. This variable increase proved to be due to variable release in vitro of transcobalamin III (TC III) from granulocytes. UBBC increase was greatest (up to fourfold normal levels) in the presence of lithium, which is the heparin salt used in many laboratories doing UBBC studies. In vitro increase was least when blood was collected in EDTA at 0 degrees C and immediately centrifuges at 0 degrees C (T(0) sample); results equivalent to T(0) were obtained at room temperature even after several hours delay when 47 mM fluoride was present; either cold temperature or 47 mM fluoride appeared to prevent TC III release from granulocytes. The measured levels of the three transcobalamins with T(0) methods of collection, which presumably reflect most closely the in vivo circulating levels, suggest that TC I and TC III in normal plasms are of the same order of magnitude and together normally comprise less than 10% of the UBBC. Approximately 90% of the UBBC content of sonicates of peripheral blood granulocytes and of bone marrow aspirates of normal individuals appears to be TC III, with the rest being TC I. Thus, normal myelocytes, like normal granulocytes, appear to contain mainly TC III. No TC II was present in any of the sonicates. The general practice in most laboratories has been to determine serum UBBC. Because in vitro increments of up to 119% were found to occur in serum, this practice should be replaced by collection using methods that prevent such increments. Blood collected in EDTA-47 mM NaF had a stable, reproducible UBBC with no significant in vitro increment with time.EDTA-NaF UBBC was 640+/-168 (range 380-921 pg B(12) bound/ml plasma) for 12 normal adult men and 809+/-232 (range 505-1208) for normal adult women. It presumably approximates circulating UBBC and is substantially below the serum UBBC mean of 935+/-262 (range 611-1506 for the same 12 men) and 1273+/-355 (range 811-2306 for the same 10 women).