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1.
Eur J Appl Physiol ; 116(8): 1583-93, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27306382

RESUMO

PURPOSE: Compare capillary and venous blood in the analysis of concentration and function of leucocyte sub-populations. This study hypothesised that capillary samples may be used in a site-specific manner as an alternative source of blood samples for assays of leucocyte concentration and neutrophilic phagocytic function and reactive oxygen species (ROS) production, allowing acquisition of multiple samples to better monitor transient but significant post-exercise immune modulation. METHODS: Resting blood samples were simultaneously obtained from vein, finger and earlobe of healthy subjects (n = 10, age: 25.1 ± 3.1 years). Leucocyte concentrations were measured using a five-part differential haematological analyser. Leucocyte sub-populations (CD3, CD4, CD8, CD19, CD56, CD14) and granulocytic functional-related (CD11b, CD18, CD16b, CD66b) surface antigen markers, neutrophil phagocytosis (FITC-labelled Escherichia coli) and stimulated ROS production (DHR) were quantified utilizing flow cytometry. A MANOVA (α < 0.05 significance) analysed the effects of the different sampling sites in the concentrations of leucocyte populations, their surface antigen expression and granulocytic functions. RESULTS: Leucocyte concentration and neutrophilic ROS production yielded non-significant differences between sampling sites. Expression of granulocytic surface antigens was increased in both capillary sites compared to venous site (p = 0.008), particularly for adhesion markers CD11b/CD18. The percentage of neutrophils performing phagocytosis was higher in venous samples compared to finger (p = 0.025). Increased number of E. coli ingested was observed in venous sample compared to finger (p = 0.001) and to earlobe (p = 0.006). CONCLUSION: Whilst attention must be paid for varying neutrophilic surface antigen expression and further studies are needed to establish appropriate reference ranges, this study supports the use of capillary blood samples in a site-specific manner to enhance sampling capabilities field-based research.


Assuntos
Capilares/citologia , Citocinas/imunologia , Contagem de Leucócitos/métodos , Leucócitos/citologia , Leucócitos/imunologia , Veias/citologia , Adulto , Capilares/imunologia , Feminino , Humanos , Leucócitos/classificação , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Veias/imunologia
2.
Sci Total Environ ; 556: 219-30, 2016 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-26974570

RESUMO

This study is an investigation into the roles of wildfire and changing agricultural practices in controlling the inter-decadal scale trends of suspended sediment production from semi-arid mountainous rivers. In the test case, a decreasing trend in suspended sediment concentrations was found in the lower Salinas River, California between 1967 and 2011. Event to decadal scale patterns in sediment production in the Salinas River have been found to be largely controlled by antecedent hydrologic conditions. Decreasing suspended sediment concentrations over the last 15years of the record departed from those expected from climatic/hydrologic forcing. Sediment production from the mountainous headwaters of the central California Coast Ranges is known to be dominated by the interaction of wildfire and large rainfall/runoff events, including the Arroyo Seco, an ~700km(2) subbasin of the Salinas River. However, the decreasing trend in Salinas River suspended sediment concentrations run contrary to increases in the watershed's effective burn area over time. The sediment source area of the Salinas River is an order of magnitude larger than that of the Arroyo Seco, and includes a more complicated mosaic of land cover and land use. The departure from hydrologic forcings on suspended sediment concentration patterns was found to coincide with a rapid conversion of irrigation practices from sprinkler and furrow to subsurface drip irrigation. Changes in agricultural operations appear to have decreased sediment supply to the Salinas River over the late 20th to early 21st centuries, obscuring the influence of wildfire on suspended sediment production.

3.
Gerontology ; 56(2): 175-80, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-19776557

RESUMO

There are limited investigations which have examined the relationship between neutrophil activation and erythrocyte aggregation in older persons. The purpose of the present study was to investigate the relationship between neutrophil activation and erythrocyte aggregation (EA) in an aging population. Twenty-eight male and female subjects were allocated into one of four groups with 7 participants in each group (group 1, 20-29 years; group 2, 30-39 years; group 3, 40-49 years; group 4, 50-59 years). EA was determined using the Myrenne aggregometer. Neutrophil function (respiratory burst and phagocytic activity) was assessed using flow cytometry. EA was found to increase with age. An ANOVA showed a significant (p < 0.05) increase for EA in autologous plasma in group 4 compared to groups 1 and 2. An ANOVA and Pearson's correlation showed that phagocytic activity decreased with age. Furthermore, a positive correlation between stimulated phagocytic activity and erythrocyte aggregability at low shear in 3% dextran-70 solution was observed. The current investigation suggests a decrease in neutrophil phagocytic activity with age and EA was increased with age. Additionally, the current study is novel as it suggests a possible relationship between neutrophil phagocytic activity and erythrocyte aggregability.


Assuntos
Envelhecimento/sangue , Agregação Eritrocítica , Neutrófilos/fisiologia , Adulto , Envelhecimento/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neutrófilos/imunologia , Fagocitose , Explosão Respiratória , Adulto Jovem
4.
Int J Sports Med ; 23(1): 22-7, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11774062

RESUMO

This study investigated the effect of 10 W*min(-1) (Slow ramp, SR), 30 W*min(-1) (Medium ramp, MR) and 50 W*min(-1) (Fast ramp, FR) exercise protocols on assessments of the first (VT1) and second (VT2) ventilation thresholds and peak oxygen uptake (VO(2)peak) in 12 highly-trained male cyclists (mean +/- SD age = 26 +/- 6 yr). Expired gas sampled from a mixing chamber was analyzed on-line and VT1 and VT2 were defined as two break-points in 20-s-average plots of pulmonary ventilation (V(E)), ventilatory equivalents for O(2) (V(E)/VO(2)) and CO(2) (V(E)/VCO(2)), and fractions of expired O(2) (F(E)O(2)) and CO(2) (F(E)CO(2)). Arterialized-venous blood samples were analyzed for blood-gas and acid-base status. VO(2)peak was significantly lower (p < 0.05) for SR (4.65 +/- 0.53 l small middle dot min(-1)) compared to MR (4.89 +/- 0.56 l *min(-1)) and FR (4.88 +/- 0.57 l *min(-1)) protocols. CO(2) output and blood PCO(2) were lower (p < 0.05), and V(E)/VCO(2) was higher (p < 0.05), above VT1 for SR compared to MR and FR protocols. No significant differences were observed among the protocols for VO(2), % VO(2)peak, V(E), plasma lactate ([La(-)]) and blood hydrogen ion concentration ([H(+)]), and heart rate (HR) values at VT1 or VT2. The work rate (WR) measured at VT1, VT2 and VO(2)peak increased (p < 0.05) with steeper ramp slopes. It was concluded that, in highly-trained cyclists, assessments of VT1 and VT2 are independent of ramp rate (10, 30, 50 W*min(-1)) when expressed as VO(2), % VO(2)peak, V(E), plasma [La(-)], blood [H(+)] and HR values, whereas VO(2)peak is lower during 10 W*min(-1) compared to 30 and 50 W*min(-1) ramp protocols. In addition, the WR measured at VT1, VT2 and VO(2)peak varies with the ramp slope and should be utilized cautiously when prescribing training or evaluating performance.


Assuntos
Ciclismo/fisiologia , Teste de Esforço/métodos , Exercício Físico/fisiologia , Consumo de Oxigênio/fisiologia , Ventilação Pulmonar/fisiologia , Adulto , Limiar Anaeróbio/fisiologia , Frequência Cardíaca/fisiologia , Humanos , Ácido Láctico/sangue , Masculino , Volume Plasmático/fisiologia
5.
Br J Haematol ; 98(3): 673-85, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9332326

RESUMO

The pattern and the sequence of tumour necrosis factor-alpha (TNF alpha) induced cell death in the acute T-lymphoblastic leukaemic cell line CCRF-CEM and its vinblastine-resistant subline CEM/VLB100 have been studied. Previously, we found that the CEM/VLB100 cell line was more sensitive to TNF alpha-induced killing than its parental CCRF-CEM cell line. TNF alpha-induced cell death showed an apoptotic pattern, as detected by agarose electrophoresis, flow cytometry and transmission electron microscopy (TEM). TEM images revealed that autophagy and codensed mitochondria occurred earlier than nuclear fragmentation. The specific inhibitor of autophagy, 3-methyladenine (3MA), inhibited the formation of autophagosomes. TNF alpha-induced DNA fragmentation and cytolysis were completely inhibited by 10 mM 3MA. Inhibition of the fusion of lysosomes with autophagosomes by asparagine did not block TNF alpha-induced apoptosis. In addition, amino acid and protein deprivation enhanced TNF alpha-induced autophagy but not apoptosis. We propose that the early stages of autophagy are required for, but do not necessarily result in, TNF alpha-induced apoptosis.


Assuntos
Apoptose/fisiologia , Leucemia-Linfoma de Células T do Adulto/patologia , Fator de Necrose Tumoral alfa/farmacologia , Autofagia/fisiologia , Humanos , Lisossomos/patologia , Microscopia Eletrônica , Mitocôndrias/patologia , Células Tumorais Cultivadas
6.
Am J Physiol ; 270(4 Pt 2): R838-45, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8967414

RESUMO

We investigated how moderate exercise affects neutrophil microbicidal activity and whether exercise-induced responses are associated with changes in growth hormone (GH) secretion. Biological fluctuations were controlled for and GH secretion was manipulated by glucose ingestion. In eight men, 1 h of moderate exercise increased intracellular H2O2 generation in response to phorbol 12-myristate 13-acetate stimulation by threefold (P = 0.025) and complement receptor expression by 20% (P = 0.045). These responses were accompanied by a twofold increase in the plasma concentration of elastase, a marker of neutrophil activation in vivo. The plasma concentration of GH increased 10-fold after exercise, but this was reduced to 3-fold by glucose ingestion (P < 0.001), which also blunted elastase release (P < 0.001). Although the magnitude of H2O2 generation increased in proportion to the increase in plasma GH concentration, it declined progressively once this exceeded 20 ng/ml. The net response of neutrophils to exercise may represent a balance between the individual responses of subpopulations that are unaffected, primed, or fully activated by circulating mediators that respond to exercise and to dietary glucose intake.


Assuntos
Neutrófilos/fisiologia , Esforço Físico , Adulto , Citometria de Fluxo , Hormônio do Crescimento/sangue , Humanos , Elastase de Leucócito/sangue , Luz , Masculino , Elastase Pancreática/sangue , Receptores Imunológicos/metabolismo , Explosão Respiratória , Espalhamento de Radiação
7.
Med Sci Sports Exerc ; 25(11): 1252-8, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8289612

RESUMO

Aerobic exercise has an established role in modulation of peripheral leukocyte concentrations. However, the effects of intense interval exercise, as employed by athletes in a range of sports, has been given little attention. Eight trained male athletes of mean age (SD) = 31.5 (4.5) yr; VO2max = 64.3 (3.8) ml.kg-1.min-1 undertook an intense interval exercise protocol (treadmill running) to exhaustion. Subjects completed an average of 15.6 1-min efforts. The protocol produced a biphasic leukocytosis: an initial (immediately posttest) leukocytosis resulting from mobilization of lymphocytes (CD3+, CD4+, CD8+, CD16+/56+, CD3+HLA/DR+) (all P < 0.01), with the later (6 h) leukocytosis resulting from mobilization of granulocytes and monocytes (both P < 0.01). This protocol modified significantly the peripheral blood concentration of the hormones cortisol (both total and free), norepinephrine, DHPG, and dopamine (all P < 0.01). Modulation of peripheral leukocyte subsets induced by interval exercise correlated with both the number of exercise efforts performed and the concomitant changes in peripheral hormone concentrations. Sustained alterations in plasma catecholamine levels in the posttest period may have important metabolic and immunological implications for athletes undertaking regular interval training.


Assuntos
Catecolaminas/sangue , Exercício Físico/fisiologia , Hidrocortisona/sangue , Leucócitos/fisiologia , Corrida/fisiologia , Adulto , Humanos , Contagem de Leucócitos , Leucocitose/fisiopatologia , Subpopulações de Linfócitos/fisiologia , Masculino
8.
Med Sci Sports Exerc ; 25(7): 778-82, 1993 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8350698

RESUMO

Iron and iron-binding proteins play a critical role in the physiology of many human systems, including the immune system. Intense interval exercise in trained men (mean [SD] age = 31.5 [4.5] yr; VO2max = 64.3 [3.8] ml.kg-1.min-1) is associated with significant modulation of iron status parameters. The concentration of red blood cells, hemoglobin, and transferrin all increased significantly immediately post-test (P < 0.01), increases which can largely be attributed to hemoconcentration. Serum iron was elevated by approximately 25% both immediately and 1 h post-test (P < 0.08). Maximum post-test serum iron values (either immediately or 1 h post-test) were significantly elevated with respect to rest (P < 0.01). Transferrin concentration was also significantly elevated at 24 h post-test (P < 0.05). Transferrin saturation was not significantly altered by this protocol (P > 0.10). Despite a trend toward elevation at 24 h post-test, ferritin concentration was not significantly different from the resting value at any sampling point. Intense interval exercise appears to be associated with significant modulation of iron status, the biological importance of which remains to be determined.


Assuntos
Ferro/sangue , Esforço Físico/fisiologia , Aptidão Física/fisiologia , Adulto , Contagem de Eritrócitos , Teste de Esforço , Ferritinas/sangue , Hematócrito , Hemoglobinas/análise , Humanos , Lactatos/sangue , Masculino , Consumo de Oxigênio/fisiologia , Resistência Física/fisiologia , Transferrina/análise
9.
J Leukoc Biol ; 53(5): 591-7, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-8501397

RESUMO

Activation of granulocytes has been associated with normal immune function, inflammation, and exercise-induced muscle damage. The effect of intense interval running on granulocyte activation was examined by use of flow cytometry, monoclonal antibodies, and spectrophotometric techniques. Eight trained males [maximal oxygen uptake VO2max, mean (SD) = 64.4 (3.6) ml/kg/min; age 30.1 (4.8) years] undertook an intense interval exercise (treadmill running) protocol to exhaustion. Subjects completed an average of 16.5 one-minute runs. Granulocyte expression of CR3 (CD11b), receptor for complement component C3bi (6 and 24 h post-test), and Fc gamma RIII (CD16) (24 h post-test) and the plasma concentration of elastase-inhibitor complex (1 h post-test) increased significantly (all P < .05). Subjects (8 of 8) exhibited a post-test decrease at either 1 or 6 h (P < .01) and a 24-h post-test significant increase (7 of 8; P < .05) in granulocyte 90 degrees light scattering (LS). Plasma lactoferrin (Lf) concentration, although increased by 17% at 6 h post-test, was not significantly different from resting values at any sampling point. Changes in plasma Lf and median channel 90 degrees LS were significantly correlated (r = -.43, P = .04), raising the possibility of monitoring exercise-induced granulocyte activation (degranulation) by flow cytometry. Intense interval exercise appears to induce granulocyte activation, as manifested by release of granule proteins and changes in 90 degrees LS and expression of both Fc and complement receptors.


Assuntos
Granulócitos/citologia , Granulócitos/fisiologia , Corrida/fisiologia , Adulto , Anticorpos Monoclonais , Teste de Esforço , Citometria de Fluxo , Granulócitos/química , Humanos , Lactoferrina/sangue , Antígeno de Macrófago 1/análise , Masculino , Consumo de Oxigênio/fisiologia , Elastase Pancreática/sangue , Espectrofotometria , Fatores de Tempo
10.
Eur J Appl Physiol Occup Physiol ; 66(4): 366-71, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8495701

RESUMO

This investigation provides an insight into the physiological changes produced, and processes operating, during and after a typical interval exercise training regime. The role of interval exercise in the modulation of the plasma concentration of sex hormone binding globulin (SHBG) and the hormones beta-oestradiol, testosterone, prolactin and growth hormone was assessed. Eight trained male athletes [mean maximal oxygen uptake (VO2max) 64.3 (SD 3.8) ml.kg-1 x min-1, mean age 31.5 (SD 4.5) years] undertook an intense interval exercise (treadmill running) protocol to exhaustion. Subjects completed an average of 15.6 x 1-min runs. This interval protocol produced significant increase in the plasma concentration of SHBG and all four hormones (all P < 0.01) in the immediate post-test period. The plasma concentration of the hormones increased as indicated: beta-oestradiol (45%), testosterone (38%), prolactin (230%), growth hormone (2000%). These hormones have an established capacity to interact with components of many physiological systems and, as such, may provide a mechanism for the changes induced by intense exercise in many of these systems.


Assuntos
Estradiol/sangue , Exercício Físico/fisiologia , Globulina de Ligação a Hormônio Sexual/análise , Testosterona/sangue , Adulto , Teste de Esforço , Hormônio do Crescimento/sangue , Humanos , Masculino , Prolactina/sangue , Radioimunoensaio , Fatores de Tempo
11.
Med Sci Sports Exerc ; 24(12): 1332-8, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1470015

RESUMO

There is evidence that the stress of intense athletic competition and training depresses cellular immunity and predisposes athletes to increased infection. This paper reports changes in circulating leukocyte subsets of trained (group I: VO2max = 67.2 +/- 5.4 ml.kg-1min-1; age = 22.0 +/- 6.2 yr) and untrained (group II: VO2max = 55.0 +/- 4.9 ml.kg-1min-1; age = 21.4 +/- 2.0 yr) males following 1 min of bicycle ergometry at maximum effort. Significant post-exercise increases in concentrations of total leukocytes, monocytes, lymphocytes, CD3+, CD4+, CD8+ lymphocytes were observed in both groups (all P < 0.01). The CD4/CD8 ratio decreased significantly (P < 0.01) but the granulocyte concentration was not altered (P > 0.05). Despite groups I and II not differing in either peak power or total work performed during the exercise test (P > 0.05), group II had a significantly greater concentration and percentage of CD8+ lymphocytes immediately after exercise (P < 0.01). All of the early changes were transient, with normalization occurring within 1 h. Only trained subjects showed a significant decrease in the percentage of CD25+ lymphocytes following PHA stimulation of whole blood obtained 6 h post-exercise. Alterations in leukocyte subpopulations found in response to predominantly anaerobic exercise appear to be associated with a significant, but possibly transient, alteration in the mitogenic responsiveness of lymphocytes that is restricted to aerobically trained subjects.


Assuntos
Exercício Físico/fisiologia , Lactatos/sangue , Subpopulações de Linfócitos/imunologia , Receptores de Interleucina-2/metabolismo , Adolescente , Adulto , Complexo CD3/sangue , Antígenos CD4/sangue , Antígenos CD8/sangue , Teste de Esforço , Humanos , Contagem de Leucócitos , Masculino , Aptidão Física/fisiologia , Fatores de Tempo
12.
Muscle Nerve ; 14(3): 219-25, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1710316

RESUMO

Tubular aggregates may be found in a variety of conditions and have been associated with a wide range of chemical and ischemic insults. We report clinical and histological features in a case of myopathy with tubular aggregates. The structure of these tubular aggregates was examined using antibodies to cytoskeletal proteins and heat shock proteins. Epitopes of the 72 kD heat shock protein were expressed in the areas of abnormality in this case and in a case of hypokalemic periodic paralysis with tubular aggregates. Heat shock proteins have a role in the modulation of the tertiary structure of proteins and may be involved in the pathogenesis of tubular aggregates and other microtubular abnormalities in muscle.


Assuntos
Epitopos/análise , Proteínas de Choque Térmico/imunologia , Músculos/química , Doenças Musculares/metabolismo , Adulto , Biópsia , Proteínas de Choque Térmico/análise , Humanos , Técnicas Imunoenzimáticas , Masculino , Microtúbulos/química , Músculos/ultraestrutura , Doenças Musculares/patologia , Paralisias Periódicas Familiares/patologia
13.
J Bone Joint Surg Br ; 73(1): 25-8, 1991 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1991768

RESUMO

Tissues from five patients who underwent revision operations for failed total hip replacements were found to contain large quantities of particulate titanium. In four cases this metal must have come from titanium alloy screws used to fix the acetabular component; in the fifth case it may also have originated from a titanium alloy femoral head. Monoclonal antibody labelling showed abundant macrophages and T-lymphocytes, in the absence of B-lymphocytes, suggesting sensitisation to titanium. Skin patch testing with dilute solutions of titanium salts gave negative results in all five patients. However, two of them had a positive skin test to a titanium-containing ointment.


Assuntos
Prótese de Quadril/efeitos adversos , Hipersensibilidade/etiologia , Titânio/efeitos adversos , Anticorpos Monoclonais , Parafusos Ósseos , Humanos , Macrófagos/ultraestrutura , Microscopia Eletrônica , Falha de Prótese , Reoperação , Testes Cutâneos , Linfócitos T/ultraestrutura
16.
Acta Endocrinol (Copenh) ; 85(2): 249-55, 1977 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-194441

RESUMO

Measurements were made on electron micrographs of six human anterior pituitary glands of the maximal diameters of secretory granules in 130 cells, average 91 granules per cell. This was done in an attempt to classify the various hormone types solely by differences in the mean diameters of the secretory granules. The range of diameters in nanometers could be segregated into six subgroups of the following suggested functions: 135.5 +/- 13.6 TSH, 181.6 +/- 9.3 LH, 226.0 +/- 19.4 FSH, 356.8 +/- 30.5 ACTH/MSH, 452.9 +/- 23.8 GH, 559.9 +/- 38.0 prolactin.


Assuntos
Grânulos Citoplasmáticos/ultraestrutura , Hormônio do Crescimento/metabolismo , Adeno-Hipófise/ultraestrutura , Hipófise/ultraestrutura , Hormônio Adrenocorticotrópico/metabolismo , Hormônio Foliculoestimulante/metabolismo , Humanos , Hormônio Luteinizante/metabolismo , Hormônios Estimuladores de Melanócitos/metabolismo , Adeno-Hipófise/metabolismo , Prolactina/metabolismo , Tireotropina/metabolismo
17.
Acta Endocrinol (Copenh) ; 79(3): 417-20, 1975 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1173499

RESUMO

Diameters of secretory granules in thyrotrophs in gonadotrophs were measured in electron micrographs of operation specimens of 4 pituitary glands and of the secretory granules in operation specimens of 10 clinically non-functioning chromophobe adenomas. The mean diameter of the thyrotroph granules was 137 plus or minus 26 nm, of the gonadotrophs 204 plus or minus 38 nm, of 9 of the adenomas 141 plus or minus 20 nm and of the remaining adenoma 248 plus or minus 67 nm. The significance of the close correlation in granule size in most of the adenomas with that of thyrotrophin granules is discussed briefly.


Assuntos
Adenoma Cromófobo/patologia , Grânulos Citoplasmáticos/ultraestrutura , Neoplasias Hipofisárias/patologia , Tireotropina , Adenoma Cromófobo/metabolismo , Humanos , Neoplasias Hipofisárias/metabolismo , Tireotropina/metabolismo
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