Neutralization of human serum beta-lysin by sodium polyanetholsulfonate and sodium amylosulfate.

Normal fresh and heat-inactivated (56 degrees C, 30 min) human sera (80 vol%, i.e., 80% [vol/vol] of a 2-ml assay volume) killed Bacillus subtilis ATCC 6633 cell inocula of 1.5 x 10(4) colony-forming units per ml within 1 to 2 h after exposure. The B. subtilis assay strain proved slightly and reversibly susceptible to 5 mug of egg white lysozyme per ml. Seitz filtration of fresh human serum completely removed beta-lysin activity; significant amounts of serum lysozyme were removed as well, as determined with the bioassay strain Micrococcus lysodeikticus ATCC 4698. However, bactericidal activity of human serum via classical or alternative complement pathway activation remained intact. Addition of 0.01 M dithiothreitol to fresh human serum abolished beta-lysin activity, but not that of serum lysozyme. Chelation of fresh and heat-inactivated human serum with 0.01 M MgCl(2) + 0.01 M ethylene glycol tetraacetic acid, but not with 0.01 M ethylenediaminetetraacetic acid, markedly retarded beta-lysin activity; however, lysozyme activity remained unaffected. Chelation of serum with 0.01 M MgCl(2) + 0.01 M ethylene glycol tetraacetic acid + 0.01 M CaCl(2) completely abrogated beta-lysin activity, but not that of lysozyme. Absorption of human serum with 10 mg of bentonite per ml (10 min, 37 degrees C) completely removed beta-lysin and lysozyme activity, but failed to affect serum bactericidal activity against Escherichia coli control strain C. Reconstitution of 50 vol% of bentonite-absorbed serum with 40 vol% of heat-inactivated human serum restored both beta-lysin and lysozyme activity. Addition of either 63 to 500 mug of sodium polyanetholsulfonate per ml or 63 to 500 mug of sodium amylosulfate per ml to 80 vol% of fresh human serum completely neutralized beta-lysin activity for the entire observation period of 22 h.     

Generation of Heat-Labile Chemotactic Activity in Blood after Inhalation Challenge and its Relationship to Neutrophil and Monocyte/Macrophage Turnover and Activity

The chemotactic activity of serum has been monitored in eight patients with bronchial asthma after inhalation of an allergen. Lactoferrin and lysozyme were measured in serum simultaneously as markers of neutrophil and monocyte/macrophage activity and turnover. The heat-labile chemotactic activity of serum showed a two-phase response with an initial reduction in activity (median = 37.5 min after challenge) ( P < 0.05) followed by an increased activity (median = 60 min after challenge) ( P < 0.01). The consistency of this pattern was highly significant ( P < 0.0005). Heat-stable chemotactic activity was significantly increased ( P < 0.01) 15 min after challenge.
The initial reduction in heat-labile chemotactic activity was observed only in those patients who developed a late asthmatic response and could suggest the involvement of immune complex-mediated reactions since a similar reduction in heat-labile chemotactic activity is produced by in vitro activation of serum with aggregated IgG.
The increased heat-labile chemotactic activity showed a close relationship ( P < 0.01) to the extent of the immediate reduction in PEF-rate. No relationship was discernible between the chemotactic activity and the eventually occurring rise in PMN blood count. In contrast the activity and turnover of PMNs after challenge as reflected by serum-lactoferrin levels were significantly reduced ( P < 0.01). A close correlation ( P < 0.001) was found between the heat-labile chemotactic activity in serum and the serum-levels of lysozyme, suggesting the involvement of macrophages/monocytes in the asthmatic reaction and in the generation of the heat-labile chemotactic activity found in serum after inhalation challenge.     

肝移植围术期血浆一氧化氮和一氧化氮合酶活性的变化及意义

目的：动态观察肝移植围术期血浆一氧化氮（NO）水平和一氧化氮合酶（NOS）活性的变化，并探讨其意义。 方法： 30例终末期肝病患者接受原位肝移植术。用放免法、比色法分别测定肝移植围术期5个时点血浆NO2-/NO3-水平和NOS活性，观察其动态变化。同步抽取桡动脉和肺动脉血做血气分析，记录不同时期的PO2、PCO2、SO2、Hb，根据肺内分流标准模型公式计算(Qs/Qt)。并监测围术期心输出量（CO）、心率（HR）、中心静脉压（CVP）、平均动脉压（MABP）、体循环阻力（SVR）。 结果： (1) 无肝前10 min NO2-/NO3-水平明显高于麻醉后术前。无肝期30 min NO2-/NO3-显著低于无肝前10 min。新肝期30 min NO2-/NO3-显著高于麻醉后术前、无肝期30 min。（2）TNOS活性各时点无显著差异。无肝前10 min、新肝30 min时iNOS活性明显高于麻醉后术前。与无肝30 min值比较，新肝期30 min iNOS活性显著升高。（3）MABP在开放下腔静脉后1 min明显下降，CO和CVP在无肝期下降，新肝期增高。SVR在无肝期增高，新肝期明显下降。（4）Qs/Qt在无肝期下降，新肝期30 min升高。 结论： 在肝移植围术期各个时段，NO水平及iNOS活性各不相同。高NO水平可能是新肝期低阻力、肺内分流增加的原因。     

Characterization of macrophage functions in mice infected with Brucella abortus.

Macrophage spreading, surface receptor density/avidity, phagocytosis, random migration, chemotactic responsiveness, and serum lysozyme were examined during the course of infection (up to 60 days) of mice with Brucella abortus strain 19. Markedly enhanced in vitro spreading activity was observed throughout the period of study. The density/avidity of cell surface immunoglobulin G Fc receptors was increased for up to 60 days postinfection. Internalization of sheep erythrocytes via C3 receptors was significantly enhanced. Random locomotion and chemotactic responsiveness to lymphocyte-derived chemotactic factor and N-formyl-L-methionyl-L-leucyl-L-phenylalanine were markedly stimulated. Serum lysozyme was also elevated in infected animals. These changes indicated significant and prolonged enhancement of macrophage activity during Brucella infection. These findings are discussed in relation to previous reports describing macrophage activation by Brucella.     

Hyperglycemic and Hyperosmolar Responses to Graded Hemorrhage

Changes of the arterial plasma osmolality and of the glucose concentration were followed during a 30 min period of graded hemorrhagic hypotension (80, 50, and 30 mmHg) in the cat. Bleeding evoked a significant plasma hyperosmolality at all three hypotension levels and the responses were quantitatively related to the degree of hypotension. An approximate steady state increase in the arterial plasma osmolality was reached about 20 min after the start of the bleeding and it then averaged 8, 20, and 25 mOsm/kg H₂O at 80, 50, and 30 mmHg, respectively. Bleeding also evoked an increase in the plasma glucose concentration, which almost entirely accounted for the observed hyperosmolality, especially at 80 and 50 mmHg. In late stages of hypotension at 30 mmHg, elevated plasma lactate and potassium concentrations contributed to the overall hyperosmolality. — Previous hemorrhagic hypotension experiments at 50 mmHg (Järhult 1975 b) have shown that hyperosmolality serves as an important regulator of the plasma and extracellular fluid volumes during bleeding. The present results indicate that such an osmolar compensatory mechanism is operating over wide ranges of hemorrhagic hypotension.     

Role of lysozyme in the microbicidal activity of rat alveolar macrophages

Lysozyme release from alveolar macrophages is stimulated by exposure to particles, such as latex and zymosan, and to bacteria. Rat alveolar marcophages contain 10-fold-greater intracellualr concentrations of lysozyme and release more lysozyme after stimulation than rat blood neutrophils. During 30 min of incubation in vitro, alveolar macrophages kill more than 99% of Micrococcus lysodeikticus in the incubation mixture, whereas neutrophils kill approximately 50% of the bacteria. The bactericidal capacity of alveolar macrophages for M. lysodeikticus exceeds that of neutrophils at all bacteria-to-cell ratios tested. This bacterial killing by alveolar macrophages is inhibited when specific rabbit antirat lysozyme serum is added to the incubation mixture. Electron microscopy studies indicate that bacterial killing occurs extracellularly. Initial degradation of bacteria occurs within 5 min, and lysis is complete by 25 to 30 min. Phagocytosis of lysed bacteria is maximum after 25 to 30 min. The greater quantities of lysozyme, both intracellularly and released into the extracellular environment by alveolar macrophages, suggest that this factor may be a mechanism by which alveolar macrophages contribute to pulmonary defense.     

Xamoterol, a new selective beta-1-adrenoceptor partial agonist, in the treatment of postural hypotension

Three patients severely disabled from postural hypotension were treated with xamoterol, a selective beta-1-adrenoceptor antagonist with a high degree of partial agonist activity. Oral treatment (200 mg b.i.d.) was chosen on the basis of the effects of acute intravenous administration of xamoterol and pindolol, a non-selective beta-adrenoceptor antagonist with partial agonist activity. In these patients pindolol had a predominantly antagonist effect, whereas xamoterol had a predominantly agonist effect after intravenous administration. Oral treatment was carried out with placebo control in a single-blind fashion. The patients reported gradual improvement during the first days of treatment. After 1 month of oral treatment, heart rate had increased by 15 beats/min, systolic blood pressure from 131 to 170 mmHg, diastolic blood pressure from 77 to 91 mmHg and mean blood pressure by 22 mmHg (mean values, supine). During the placebo period (2 weeks) heart rate decreased to pretreatment levels and mean blood pressure was reduced by only 14 mmHg. The patients reported substantial improvement in their condition during active medication. Xamoterol seems to be a useful alternative in the treatment of postural hypotension.     

Lysozyme in the serum, urine and peripheral blood leukocytes in patients with immunocytoma.

Lysozyme activity was determined in the serum, urine and leukocytes of 53 patients with immunocytoma and 24 patients with lymphoproliferative syndromes without associated monoclonal gammapathy. In patients with multiple myeloma the frequency of low serum lysozyme activity and high leukocyte lysozyme activity was higher. In the cases with renal failure, lysozyme activity was raised in serum and urine, and the 24-hour urinary lysozyme excretion was increased. In 7 patients with increased urinary lysozyme excretion no clinical or laboratory evidence of renal complications was found. Relative monocytosis in peripheral blood was observed in half of the cases of multiple myeloma, and in these patients also in about half of the cases the lysozyme activity was raised in the leukocytes and urine, and the 24-hour urinary lysozyme excretion was increased. In patients with Hodgkin's disease, lymphosarcoma and chronic lymphatic leukemia the frequency of low serum lysozyme activity was increased.     

Cellular immunity in patients with psoriasis

The angiotensin converting enzyme activity was determined in a dog's plasma in the course of an irreversible hemorrhagic shock development. A statistically significant increase of the angiotensin converting enzyme activity in the plasma was found after one hour and two hours' duration of posthemorrhagic hypotension. After one hour and two hours' duration of posthemorrhagic hypotension the plasma angiotensin converting activity was higher by 29% and 33%, respectively, compared with the control levels determined in the normotensive period. After three hours' duration of posthemorrhagic hypotension the plasma activity of the angiotension converting activity was even more evident. In these conditions the plasma enzyme activity was increased by 71% compared to the control levels. The results obtained indicate the possibility that certain changes occur at the endothelial level of pulmonary blood vessels during the hemorrhagic shock development. These changes suggest an intense angiotensin converting enzyme release into the systemic circulation. The results of this investigation are a contribution to a better understanding of the renin-angiotensin system in shock conditions.     

Role of rabbit lysozyme in in vitro serum and plasma serum bactericidal reactions against Bacillus subtilis.

The antibacterial activity of purified rabbit lysozyme was kinetically investigated at concentrations comparable to those in normal rabbit serum and plasma serum. The bactericidal capability, lysozyme content, and electrophoretic composition of "purified beta-lysin," fractionated from normal rabbit serum, were also examined. In contrast to the extensive antibacterial activity of dilute normal rabbit serum observed in vitro, rabbit lysozyme was only weakly bactericidal for Bacillus subtilis. Inhibition of lysozyme enzymatic and bactericidal activities in normal rabbit serum by antilysozyme immunoglobulin G slightly reduced the initial rate of killing. The addition of neutralizing antibody or histamine (another lysozyme inhibitor) to partially purified bactericidal serum fractions had no effect on killing kinetics. Increasing the ionic strength of reaction mixtures containing normal serum or partially purified bactericidal fractions to levels which completely inhibited lysozyme activity resulted in stimulation of their respective killing kinetics. The addition of inhibitors to normal rabbit plasma serum completely eliminated its bactericidal activity. With regard to the killing of B. subtilis by rabbit and human blood fractions, these analyses clearly demonstrated that (i) although lysozyme is not a significant antibacterial component of normal rabbit serum, it represents the principal factor in normal rabbit plasma serum; (ii) different primary bactericidal mechanisms which are not detectable by singlepoint analyses operate in the sera of different species; and (iii) purified beta-lysin isolated from normal rabbit serum by the classical procedure is a heterogenous mixture of components.     

Sympathetic responses to Valsalva's manoeuvre following bed rest.

The purpose of this study was to examine whether 14 days of head-down tilt bed rest (HDBR) alters autonomic regulation during Valsalva's manoeuvre (VM) and if this would predict blood pressure control during a 60 degrees head-up tilt (HUT) test. To examine autonomic control of blood pressure, we measured the changes in systolic (delta SBP) and diastolic (delta DBP) blood pressure between baseline and the early straining (Phase IIE) period of VM (20 sec straining to 40 mmHg; N = 7) in conjunction with changes in muscle sympathetic nerve activity (MSNA; microneurography) burst frequency (B/min) and total activity (% delta) from baseline over the 20-sec straining period. MSNA data were successfully recorded from 6 of the 7 individuals. The averaged responses from three repeated VMs performed in the supine position were compared between the pre- and post-HDBR tests. Compared with the pre-HDBR test, a greater reduction in SBP, DBP, and MAP was observed during Phase IIE following HDBR, p < 0.05. The increase in MSNA burst frequency during straining was augmented in the post- compared with the pre-HDBR test, p < 0.0001, as was the Phase IV blood pressure overshoot, p < 0.05. Although all subjects completed the 20-min pre-HDBR tilt test without evidence of hypotension or orthostatic intolerance, the post-HDBR test was stopped early in 5 of the 7 subjects due to systolic hypotension. The responses during the VM suggest that acute autonomic adjustments to rapid blood pressure changes are preserved after bed rest. Furthermore, MSNA and blood pressure responses during VM did not predict blood pressure control during orthostasis following HDBR.     

Reflex Inhibition of Sympathetic Nerve Activity by Phenoxybenzamine

The effects on baroreceptor and sympathetic nerve activity of the a-adrenergic blocking agent phenoxybemamirie have been investigated in 13 anesthetized rabbits. Nerve activities were recorded at various blood pressure levels, obtained by stepwise changes of blood volume. With phenoxybenzamine, aortic nerve activity at 80 and 90 mm Hg exceeded control values by 66 and 62 %. At the same pressures, renal nerve activity was reduced by 30 and 55 %. Although blood pressure started to fall shortly after injecting the drug, about 20 min elapsed before development of maximum effects on the nerves. When studied during stepwise changes of blood pressure after a similar period of hypotension—but without the drug-sympathetic nerve activity had increased. Phenoxybenzamine had accordingly effected a suppression of sympathetic activity, suggesting that the hypotensive response to phenoxybenzamine is aided by increased reflex inhibition of sympathetic nerve activity.     

Dynamics of bactericidal properties of human saliva and blood serum during adaptation to arctic conditions

The dynamics of the bactericidal activity of the blood serum and of the lysozyme activity of the blood and saliva was studied in persons living beyond the Arctic circle (Noril'sk). During adaptation to Arctic conditions significant changes take place in the bactericidal activity of the serum and the lysozyme titer of the serum and saliva. Together with changes in the absolute values of these parameters, their circadian rhythms are disturbed. A period of 2 years is not long enough to restore the normal bactericidal activity of the serum or the lysozyme titer.Department of Microbiology, Tomsk Medical Institute. Institute of Clinical and Experimental Medicine, Siberian Branch, Academy of Medical Sciences of the USSR, Novosibirsk. (Presented by Academician of the Academy of Medical Sciences of the USSR D. D. Yablokov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 78, No. 10, pp. 72–74, October, 1974.     

Neutralization of human serum lysozyme by sodium polyanethol sulfonate but not by sodium amylosulfate.

Sodium polyanethol sulfonate (SPS) at 500 microgram/ml, but not sodium amylosulfate (SAS) at 500 microgram/ml, precipitated egg white lysozyme (1 mg and 50 microgram of lysozyme per ml) as determined with the assay strain Micrococcus lysodeikticus ATCC 4698. Fresh and heat-inactivated (56 degrees C, 30 min) human serum (80%, vol/vol) killed M. lysodeikticus (10(4) bacteria per ml at zero time) within 1 to 2 h after exposure. Addition of 250 to 500 microgram of SPS per ml to fresh human serum protected M. lysodeikticus for 22 h as effectively as absorption of either fresh or heat-inactivated human serum with bentonite (10 mg/ml of serum, 10 min, 37 degrees C); the latter procedure is known to remove serum lysozyme. In contrast, SAS at 250 and 500 microgram/ml of serum retarded killing of the assay bacteria for periods of 4 h; after overnight (22 h) incubation, however, the number of M. lysodeikticus survivors had decreased significantly. The finding that SPS, but not SAS, at 250 to 500 microgram/ml effectively neutralized serum lysozyme-mediated killing of a lysozyme-sensitive assay strain may be of relevance with respect to laboratory processing of human blood culture specimens.     

Lysozyme: primary bactericidin in human plasma serum active against Bacillus subtilis.

The in vitro bactericidal reaction of human plasma serum against Bacillus subtilis was investigated. Human lysozyme was purified to homogeneity, and antiserum was prepared against the enzyme. The anti-lysozyme immunoglobulin G was used as a specific inhibitor in bactericidal and bacteriolytic reactions. It was found that at low serum concentrations lysozyme was the primary bactericide active against B. subtilis. At appreciably higher serum concentrations, a lysozyme-independent bactericidal activity was also demonstrated.     

Serum and tissue lysozyme in leprosy.

Mean serum lysozyme values were found to be elevated in untreated leprosy patients. Statistically significant elevations were present in each of the three major categories of leprosy, tuberculoid, borderline, and lepromatous. Values were particularly high in patients with severe reversal reactions or Lucio's phenomenon. Prolonged sulfone therapy was associated with a fall in serum lysozyme values. With an immunoperoxidase method to localize lysozyme in leprous tissues, two distinct staining patterns were found, granular and saccular. The grandular pattern of lysozymal staining was found in epithelioid cells and in giant cells, and the intensity of staining showed a positive correlation with serum lysozyme levels. Conversely, a saccular pattern of lysozymal staining was found in lepromatous histiocytes, buth the intensity of staining was unrelated to serum lysozyme levels; the saccular structures contained dense aggregates of Mycobacterium leprae. These two patterns of staining probably represent different functional responses of monocyte-derived granuloma cells, whereas the serum levels reflect, to a varying degree, both the absolute number of such cells and the rate of secretory activity of this cell population as a whole.     

Naloxone and haemorrhagic hypotension in rats. Evidence against sympathetic nervous system as the primary mediator of improved cardiovascular haemodynamics

Release of endogenous opiate-like substances seem to occur in different forms of stress. Earlier studies have shown that the opiate antagonist, naloxone, has a positive effect on cardiac performance and blood pressure in animals with haemorrhagic shock. In the present study, we have examined the involvement of the sympathetic nervous system in this response. Two groups of anaesthetized normotensive Wistar-Kyoto rats were studied. Both groups were bled rapidly (about 5 min) down to an arterial pressure of 50 mmHg and were kept at that level for 30 min. At the end of the 30-min bleeding period, naloxone 1, 2, or 5 mg kg-1 was injected i.v. in a small volume of saline. In the first group of rats (n = 6), the aortic pressure was kept constant at 50 mmHg by further bleedings after naloxone. In the other group (n = 7), the arterial pressure was allowed to rise after naloxone. As reported earlier, haemorrhagic hypotension caused a pronounced inhibition of renal sympathetic nerve activity. Naloxone injected after 30 min of hypotension caused an immediate rise in blood pressure, followed 1-2 min later by a rise in sympathetic nerve activity (SNA). In animals in which pressure was held constant by further bleeding after naloxone, only small and insignificant changes in SNA were observed. The conclusions are the following: injection of naloxone increases blood pressure in rats exposed to severe haemorrhage (Faden & Holiday 1979). The rise in aortic pressure is followed 1-2 min later by a rise in SNA.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effects of Oliviera decumbens and Satureja khuzestanica extract on some immunological and haematological parameters of Cyprinus carpio

Immunity stimulants are applied to improve the immune system of aquatic organisms. In this study, the effect of oral administration of Marze (Satureja khuzestanica) and mountainous Lael (Oliviera decumbens) extracts on haematological parameters and lysozyme activity stimulation in Common carp was investigated during a 5-week period. At the end of this period, blood samples were taken for haematological and immunological assays (lysozyme activity). The result showed that white blood cell count (p?>?0.05) and the ratio of white blood cells (p?>?0.05) were not significantly affected by plant extract administration. There were significant differences between the serum lysozyme activities in different treatments (p?<?0.05). Generally, it can be concluded that Marze extract, as an immune stimulant, has a positive effect on the immune system and increased the resistance of Common carp. The combination of Marze and Mountainous Lael extracts was also an effective immune stimulant, but Mountainous Lael extract on its own did not stimulate the immune system of Common carp.     

Post-exercise recovery of autonomic cardiovascular control: a study by spectrum and cross-spectrum analysis in humans

The recovery of the baseline autonomic control of cardiovascular activity after exercise has not been extensively studied. In 12 healthy subjects, we assessed the time-course of recovery by autoregressive spectrum and cross-spectrum analysis of heart period and systolic blood pressure during the 3 h after the end of 20 min of steady-state exercise at 50% (light workload, LW) and 80% (moderate workload, MW) of the individual's anaerobic threshold. The electrocardiogram and non-invasive blood pressure were simultaneously recorded during 10 min periods in the sitting position, at rest before exercise, and at 15, 60 and 180 min of recovery after exercise. At 15 min we observed a persistent tachycardia and relative hypotension; after MW, at 60 min heart rate was still slightly higher. Spectrum and cross-spectrum analysis showed, at 15 min, an increase in the low frequency component of systolic blood pressure, a reduction in the high frequency component of heart rate (larger in MW), and a decrease in baroreceptor sensitivity. After 60 and 180 min none of these parameters was significantly different from those at rest, although, in MW, some subjects still displayed signs of sympathetic activation after 1 h. We concluded that, after 15 min of recovery, the cardiovascular reflexes were blunted, that sympathetic nerve activity was still enhanced, and that the tone in the vagus had not fully recovered. Only the persistent vagal restraint seemed to be exercise intensity-dependent. For complete restoration of autonomic control after LW 1 h of rest was sufficient, and just enough after MW. Accepted: 2 November 2000     

Killing of an encapsulated strain of Escherichia coli by human serum.

Changes in cell viability and in factors affecting metabolic integrity were examined after exposure of Escherichia coli LP1092 to human serum. Antibody-dependent classical pathway activity accounted for the rapid killing of strain LP1092 by complement. Removal of serum lysozyme by bentonite absorption or by neutralization with anti-human lysozyme immunoglobulin G resulted in a reduction in the rate of killing; optimal activity could be restored by the addition of physiological amounts of egg-white lysozyme. The pattern of 86Rb+ and alkaline phosphatase release obtained after serum treatment did not support the view that complement simultaneously disrupts cytoplasmic and outer membrane integrity. Macromolecular synthesis was affected late in the reaction sequence; complete inhibition of precursor incorporation into RNA, DNA, and protein occurred only after almost total loss of bacterial colony-forming ability. Addition of chloramphenicol, an inhibitor of protein synthesis, to the bactericidal system resulted in a marked reduction in the rate of serum killing. Killing was completely inhibited by an inhibitor (KCN) and an uncoupler (2,4-dinitrophenol) of oxidative phosphorylation. Exposure of LP1092 cells to serum was followed by a rapid and large increase in intracellular ATP levels; ATP synthesis did not occur when bacteria were exposed to dialyzed serum, which killed LP1092 cells at a much reduced rate. Addition of glucose or serum ultrafiltrate to dialyzed serum restored optimal bactericidal activity. We suggest that optimal killing of gram-negative bacteria is an energy-dependent process requiring an input of bacterially generated ATP.