Biomedical subjects

C Barriga

Publications and source records attributed to C Barriga.

At least 55 records · Page 3Linked to original sources

PubMed1995

Effect of high summer temperatures upon granulocyte phagocytic function of the tench (Tinca tinca, L.).

Phagocytic activity and NBT reduction by blood granulocytes was evaluated in tench during the summer, when water temperature was high (30 degrees C). In vitro assays were performed at two temperatures, 30 degrees C, the temperature of the natural habitat in summer, and 22 degrees C, a commonly used temperature within the optimum range of warm-water fish. The results indicate that blood granulocytes from tench possess a lower capacity to ingest inert particles at 30 degrees C than at 22 degrees C, particularly during long periods of incubation (60 min). The lower capacity for ingesting inert particles at 30 degrees C is due to a decreased effectiveness of phagocytosis at this temperature, but not to a lower number of granulocytes with phagocytic capacity. The decline in inert particle ingestion capacity does not correspond to a lower production of superoxide anion at 30 degrees C, which is similar at both temperatures during phagocytosis, thus indicating a similar capacity for destruction of the antigen at 30 and 22 degrees C.

Animals↗

PubMed1995

Intracellular activity of both teicoplanin and vancomycin against Staphylococcus aureus in human neutrophils.

The effects in vitro of both teicoplanin and vancomycin of blood peripheral human neutrophils have been studied by assays of antibiotic uptake and intracellular killing of previously phagocytosed Staphylococcus aureus. The effects of vancomycin and teicoplanin (a novel glycopeptide antibiotic), at the therapeutic concentrations reached in plasma (10, 25, 50, 75 and 100 mg/l) and at different times of incubation (5, 15, 30 and 60 min) were studied. The results indicate that: (1) the bactericidal effect of neutrophils increases with incubation time, (2) in the presence of both teicoplanin and vancomycin, the number of CFU/ml of intraphagocytic S. aureus declines with both increasing incubation time and exposure dose of the antibiotics and (3) at 100 mg/l of teicoplanin there is a significant increase in the percentage inhibition of S. aureus growth at all the times studied.

Colony Count, Microbial↗

PubMed1995

Serum hemolytic and bactericidal activity in breast and formula-fed infants.

Whether formula or breast feeding influences the functional activity of the complement system from birth to three months of age has been studied. The classical pathway was evaluated by assessing hemolytic activity, based on the capacity of the intact complement system to lyse sheep erythrocytes when coated with specific antibodies. The bactericidal activity of the serum against Staphylococcus aureus and Escherichia coli was used to evaluate the alternative complement pathway. Sera were obtained from neonates (40 +/- 2 weeks of gestation), and one-month or three-month old infants, fed either breast or formula. Control serum was obtained from healthy adults between 22 and 30 years of age. The hemolytic capacity of serum from breast-fed infants of one month and three months of age was significantly greater than that of the serum from infants which had been fed formula milk.

Breast Feeding↗

PubMed1994

Increased phagocytic activity of polymorphonuclear leukocytes during pregnancy.

Many immunological parameters are depressed during pregnancy. For this reason, an evaluation was made of the phagocytic activity, representing non-specific immunity, of polymorphonuclear leukocytes from pregnant women. The cells were isolated from heparinized venous human blood of pregnant women of 10 or more weeks' gestation and non-pregnant women (controls), 20-30 years old. The results indicate that the phagocytosis of inert particles (latex beads) does not significantly change in pregnancy. However, the attachment, ingestion and digestion of Candida albicans significantly increased in pregnancy, with the greatest difference from controls being in the second trimester. These findings suggest that the phagocytic activity in pregnant women is enhanced and that this increased non-specific immunity may compensate in part for weakened specific immunity of the maternal host.

Adult↗

PubMed1994

Effect of age on adherence and chemotaxis capacities of peritoneal macrophages. Influence of physical activity stress.

The aim of the present research was to study the effects of age on the adherence and chemotaxis capacities of macrophages. Macrophages were obtained from the peritoneum of young and old mice (young, 12 +/- 4 weeks; old, 68 +/- 6 weeks) and young and mature guinea pigs (young, 12 +/- 1 weeks; mature, 108 +/- 2 weeks). Adherence of macrophages was evaluated with a plastic adherence technique, and chemotaxis in a Boyden chamber. The macrophages from old animals showed a higher adherence capacity (studied at 10, 40 and 60 min of incubation), and lower chemotaxis capacity in both mice and guinea pigs. The effect of physical activity stress (swimming until exhaustion) was also studied, both with and without a previous training program, on the adherence and chemotaxis of macrophages from young and old mice. While the physical activity stress (detected by the increase of the serum corticosterone concentration) did not induce changes in adherence or chemotaxis of peritoneal macrophages from young mice, in the old mice, there was a decrease in adherence and an increase in chemotaxis.

Aging↗

PubMed1994

Decline in the phagocytic function of alveolar macrophages from mice exposed to cigarette smoke.

An investigation was made of the effects of a short and acute exposure to cigarette smoke on the capacity of alveolar macrophages from mice to carry out all stages of the phagocytic process. Cigarettes were commercial 80 mm filter cigarettes that contained 17 mg of tar and 1.1 mg of nicotine per cigarette. The acute exposure of each animal was with one cigarette for 15 min (until the complete consumption of the cigarette) in a box-shaped plastic chamber, 7732 cm3 vol and 450 cm2 floor surface, with a 3 cm dia airhole. Animals were sacrificed immediately after the exposure to the smoke. The results showed no differences either in the adherence or in the chemotaxis capacities between alveolar macrophages from control mice and from mice exposed to cigarette smoke. However, there was a significant decline both in attachment capacity and in ingestion capacity for Candida albicans. The reason for this was a decline in the number of macrophages with phagocytic capacity (percent of phagocytosis) and in the number of C. albicans phagocytized per cell (phagocytic efficiency). The conclusion is that a short, acute exposure to a smoke-filled atmosphere induced a decrease in the phagocytic function of alveolar macrophages.

Animals↗

PubMed1994

[Effect of a diet supplemented with soybean oil or fish oil on the reversibility of docosahexaenoic acid deficiency (22:6w3) in the brain and erythrocytes of rats].

This study was undertaken, to evaluate the effects of dietary supplements containing either soybean oil (19:3w3; ALA), or fish oil (22:6w3; DHA), added to the lactating rat dam diet, on the levels of DHA in brain and erythrocytes of DHA deficient pups. Pregnant rats fed omega 3 deficient diets were divided at parturition into three groups. One group was kept on the same diet fed during pregnancy. The two remaining groups received the above mentioned omega 3 supplements. These feeding regimens were maintained during 18 days. Supplementation of diet with 114 mg DHA/100g diet, increased significantly the concentration of DHA in brain and erythrocytes of the suckling rats. In contrast, the effects of the supplementation with ALA (700 mg/100g diet), were limited to the increase of DHA content in the brain. This increase however, was partial, reaching only 50% of the normal. Results suggest that newborn rat has a limited capacity to convert DHA from ALA, becoming dependent of preformed DHA supply to cover DHA requirements at the cellular level.

Analysis of Variance↗

PubMed1994

Effect of cefepime (BMY-28142) on the hemolytic and bactericidal activity of serum in vivo and in vitro.

The present study was undertaken to determine whether cefepime (BMY-28142) could influence the hemolytic and bactericidal activity of serum both in vivo and in vitro. For the in vivo studies, mice (Swiss aged 15 +/- 2 weeks) were studied before and 1, 2, 4, 8, and 12 h after an intramuscular injection of 200 mg/kg of cefepime. Likewise, another group of mice were injected for 7 days with a daily injection of the same dose as before, and sacrificed one hour after the last injection. For the in vitro studies, samples were incubated in the presence and absence of cefepime (1/2, 1/4 and 1/8 MIC against Staphylococcus aureus) (2.5, 1.25 and 0.625 mg/l respectively). The results indicate that cefepime at sublethal concentrations increases the bactericidal activity of serum both in vivo and in vitro against S. aureus, but does not significantly modify the hemolytic activity of the complement.

Animals↗

PubMed1994

Influence of age and stress from physical activity on the redistribution of lymphocytes.

The influence of age and stress on the redistribution of lymphocytes between the intra- and extra-vascular spaces has been studied. Young (12 +/- 4 weeks) and old (68 +/- 6 weeks) mice were made to swim until exhaustion, with and without a previous period of training. Lymphocyte concentration in the blood and in the peritoneal cavity, was evaluated as well as the weight of spleen and thymus in these animals. In parallel, and as an indicator of the level of stress, quantification was made of the serum corticosterone levels and weight as well as the protein, DNA, and RNA content of the adrenal glands. Results indicate that, after being subjected to stress, the young mice present no changes in lymphocyte number in blood or peritoneal cavity. Old mice, however, after acute physical activity, present a greater lymphocyte content in the intravascular compartment, as well as a fall in the peritoneal lymphocyte concentration and spleen weight. The data could indicate that age modifies the response to stress, with an augmentation of lymphocytes in the intravascular compartment at the expense of the extravascular one.

Adrenal Glands↗

PubMed1993

Effect of age and of swimming-induced stress on the phagocytic capacity of peritoneal macrophages from mice.

The effect of age and physical activity stress (swimming until exhaustion) on the phagocytic capacity of the peritoneal macrophages was studied in young (12 +/- 4-week-old) and old (68 +/- 6-week-old) BALB/c mice. The attachment and ingestion of opsonized Candida albicans as well as the ingestion of inert particles (latex beads) by these cells was compared between young and old animals at rest. The results show that phagocytosis of peritoneal macrophages is not impaired in old mice. With respect to the effect of physical activity stress, we evaluated the phagocytic capacity both of C. albicans and of latex beads before and immediately after swimming until exhaustion, and in the absence or presence of a previous period (1 month) of training. The results indicate that the phagocytic capacity of peritoneal macrophages is increased after swimming until exhaustion, both with and without previous adaptation or training, and in both young and old mice.

Adaptation, Physiological↗

PubMed1993

Study of the phagocytic process in neutrophils from elite sportswomen.

All the stages of the phagocytic process of blood neutrophils were compared in sedentary young women (no formal exercise during the previous 24 months) and elite sportswomen (basketball players from the "Siglo XXI Spain Selection", in the middle of their competitive season) at rest. The sportswomen had performed no exercise since the day before taking the blood samples. Adherence of neutrophils to nylon fibre, which is similar to endothelium adherence, was not different between the two groups [62 (SD 14) and 58 (SD 18) in control and sport groups respectively]. Chemotaxis (studied in a Boyden chamber using a filter with 3 microns pore diameter) was found to be stimulated (P < 0.001) in the sportswomen [105 (SD 30)] with respect to the controls [39 (SD 9)]. Attachment, ingestion and killing by neutrophils was measured by incubation of the neutrophils with serum and a suspension of Candida albicans. While no statistical differences were found in attachment of C. albicans after 15 min incubation [71 (SD 8) in the control group, and 74 (SD 20) in the sport group], the sportswomen showed a higher (P < 0.001) ingestion capacity for C. albicans at both 15 min [53 (SD 13) and 111 (SD 32) in control and sportswomen respectively] and 60 min [control 90 (SD 10), and sport group 224 (SD 21)] incubation. The greater phagocytic capacity in sportswomen was correlated with a higher plasma cortisol concentration (P < 0.05) and a lower plasma ACTH concentration (P < 0.001) in this group.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenocorticotropic Hormone↗

PubMed1993

Stimulation of the phagocytic function of neutrophils in sedentary men after acute moderate exercise.

All the different stages of phagocytic function in blood polymorphonuclear neutrophils of sedentary (untrained) young men before, immediately after, and 15 min after being subjected to submaximal acute moderate exercise (50% maximal oxygen uptake) on a cycle ergometer were studied. No statistically significant differences were found in adherence or microbicide capacity against Candida albicans immediately after physical exercise. However, spontaneous mobility, chemotaxis and attachment and phagocytosis of Candida albicans at 15 min of incubation were significantly stimulated. Fifteen minutes after exercise spontaneous mobility, chemotaxis, and attachment of Candida albicans had returned to basal values, while phagocytosis of Candida albicans remained higher than basal values. One can, therefore, conclude that acute moderate exercise stimulates the phagocytic capacity of neutrophils in sedentary young men. In addition, no differences were found in the plasma adrenocorticotropic hormone concentration after exercise. However, immediately after exercise there was a decrease in the serum cortisol concentration, which had returned to basal 15 min later.

Adrenocorticotropic Hormone↗

PubMed1993

In vitro effect of cefoxitin on phagocytic function and antibody-dependent cellular cytotoxicity in human neutrophils.

The effects in vitro of Cefoxitin, a beta-lactam antibiotic, at a concentration of 50 micrograms/ml (similar to a therapeutic level in plasma) on each step of the phagocytic process, in addition to antibody-dependent cellular cytotoxicity (ADCC) of blood peripheral human neutrophils have been studied. The antibiotic produced a significant stimulation of adherence capacity, chemotaxis, attachment of Candida albicans to neutrophils and phagocytosis of Candida albicans (with serum, decomplemented serum or without serum), ingestion of inert particles (latex beads), microbicidal activity, and digestion capacity of the ingested material [measured by nitroblue tetrazolium (NBT) reduction]. Moreover, cefoxitin (50 micrograms/ml) demonstrated chemoattractant activity for neutrophils. ADCC was also increased by this antimicrobial agent. These results therefore suggest that a therapeutic concentration of cefoxitin may enhance microbicidal and cytotoxic functions of a pivotal human phagocytic cell: the neutrophil.

Antibody-Dependent Cell Cytotoxicity↗

PubMed1993

Stimulation of phagocytosis against Staphylococcus aureus by teicoplanin and vancomycin.

The constructive interference of teicoplanin with phagocytosis of Staphylococcus aureus by murine macrophages and human neutrophils, studied in vivo and in vitro respectively, was compared with that of vancomycin. Both teicoplanin and vancomycin increased the phagocytosis by macrophages. All the concentrations of teicoplanin increased the phagocytosis by neutrophils, but only the highest concentrations of vancomycin (50 mg/l and 100 mg/l) had this effect, greater values being found with teicoplanin in all cases.

Animals↗

PubMed1993

[Uptake and intraphagocytic activity of teicoplanin in human neutrophils].

The incorporation of antibiotics in phagocytes is necessary for their activity against intracellular microorganisms. The ability of Teicoplanin to enter in human polymorphonuclear leukocytes (PMNs) after infection with Candida albicans was investigated using an in vitro model previously described. Human PMNs were preincubated with Candida albicans for 30 min, after which antibiotic (100 mg/l) was added to cell suspension during 1, 5, 15, 30 and 60 min. The results were expressed as the ratio of the cellular concentration of antibiotic to the extracellular concentration (C/E). Teicoplanin bound rapidly to phagocytes (with a C/E = 2.12 after 1 min of incubation), being the cell-associated drug approximately similar during the entire incubation period. At the same time, Teicoplanin increases the percentage of mortality of Candida albicans previously ingested, which was dependent of the incubation period in its presence.

Adult↗

PubMed1993

Effect of submaximal physical exercise performed by sedentary men and women on some parameters of the immune system.

Submaximal physical exercise by sedentary men and women on a bicycle ergometer for 60 min at 58% (men) and 55% (women) of VO2 max. was evaluated for its effect on the number of total leukocytes (WBC), lymphocytes, monocytes and neutrophils and the percentages of CD3+, CD4+, CD8+ and CD19+ lymphocyte subpopulations, as well as on IgA, IgG and IgM serum immunoglobulin levels as one measure of B-lymphocyte function. Blood samples were collected before, immediately after, and 15 minutes after physical exercise. Exercise did not significantly change the total number of WBC, lymphocytes, monocytes or neutrophils, or the percentages of CD3+, CD4+, CD8+ and CD19+ positive cells and the IgA and Ig M immunoglobulins. However the serum level of IgG immunoglobulins immediately after exercise was significantly lower than both before (p < 0.001) and 15 min later (p < 0.05). No differences in the results between men and women were detected.

Adult↗

PubMed1992

Stimulation of the phagocytic function in guinea pig peritoneal macrophages by physical activity stress.

A study was made of all the different stages of the phagocytic function in peritoneal macrophages from male guinea pigs [3 (SD 1) months old] before, immediately after, and 24 h after being subjected to stress from physical activity (swimming until exhaustion). The early (10 min) and late (40 min) adherence to tissue substrates, chemotaxis, attachment and phagocytosis of Candida albicans, ingestion of inert particles (latex beads), and basal oxidative metabolism [measured by nitroblue tetrazolium (NBT) reduction] were significantly stimulated by the physical activity. After 24 h, late adherence, attachment capacities, and basal oxidative metabolism returned to basal values, whereas early adherence, chemotaxis, phagocytosis of cells and inert particles, and microbicidal capacity (production of superoxide anion measured by NBT reduction in presence of ingested material) remained significantly increased. The stress produced by physical activity, reflected in increased serum corticosterone values, led to a global stimulation of the phagocytic function.

Animals↗

PubMed1992

Effect of physical activity stress on the phagocytic process of peritoneal macrophages from old guinea pigs.

The different stages of the phagocytic function in peritoneal macrophages from old guinea pigs (27 +/- 3-months-old) were studied before, immediately after and 24 h after being subjected to physical activity stress (swimming until exhaustion) which raised the blood levels of corticosterone. The phagocytosis of opsonized Candida albicans was stimulated immediately after physical activity. No modifications in adherence, chemotaxis, ingestion of inert particles, or microbicide capacity, measured by nitroblue tetrazolium (NBT) reduction, were found. At 24 h, when no stress could be shown by corticosterone analysis, the phagocytosis of opsonized C. albicans remained stimulated and chemotaxis was increased while ingestion of inert particles and microbicide capacity remained unchanged. The adherence, however, was at a smaller level. No correlations were found between the corticosterone levels and the status of the phagocytic process of peritoneal macrophages.

Aging↗