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1.
This investigation examined the effects of NaHCO3 loading on lactate concentration ([La]), acid-base balance, and performance for a 603. 5-m sprint task. Ten greyhounds completed a NaHCO3 (300 mg/kg body weight) and control trial in a crossover design. Results are expressed as means +/- SE. Presprint differences (P < 0.05) were found for NaHCO3 vs. control, respectively, for blood pH (7.47 +/- 0.01 vs. 7.42 +/- 0.01), HCO-3 (28.4 +/- 0.4 vs. 23.5 +/- 0.3 meq/l), and base excess (5.0 +/- 0.3 vs. 0.2 +/- 0.3 meq/l). Peak blood [La] increased (P < 0.05) in NaHCO3 vs. control (20.4 +/- 1.6 vs. 16.9 +/- 1.3 mM, respectively). Relative to control, NaHCO3 produced a greater (P < 0.05) reduction in blood base excess (-18.5 +/- 1.4 vs. -14.1 +/- 0.8 meq/l) and HCO-3 (-17.4 +/- 1.2 vs. -12.8 +/- 0.7 meq/l) from presprint to postexercise. Postexercise peak muscle H+ concentration ([H+]) was higher (P < 0.05) in NaHCO3 vs. control (158.8 +/- 8.8 vs. 137.0 +/- 5.3 nM, respectively). Muscle [H+] recovery half-time (7.2 +/- 1.6 vs. 11.3 +/- 1.6 min) and time to predose values (22.2 +/- 2.4 vs. 32.9 +/- 4.0 min) were reduced (P < 0.05) in NaHCO3 vs. control, respectively. No differences were found in blood [H+] or blood [La] recovery curves or performance times. NaHCO3 increased postexercise blood [La] but did not reduce the muscle or blood acid-base disturbance associated with a 603.5-m sprint or significantly affect performance.  相似文献   

2.
Phagocyte myeloperoxidase (MPO) is believed to be particularly important in defense against candida infection. We reported earlier that monocytes, rich in MPO, killed Candida albicans at a significantly higher rate and extent than did monocyte-derived macrophages, known to lack MPO, and that C. albicans is less resistant to MPO-dependent oxidants than less pathogenic Candida species. We hypothesized, therefore, that the capacity of macrophages to kill C. albicans might be improved in the presence of MPO. In this study, we evaluated the ability of recombinant human MPO (rhMPO) to augment the killing of C. albicans by resident macrophages and macrophages activated by recombinant human granulocyte-macrophage colony-stimulating factor. Addition of rhMPO (concentration range, 0.8 to 6.4 U/ml) to suspensions of resident and activated macrophages and opsonized C. albicans resulted in concentration-dependent and significant increases in candida killing. This enhancement was particularly pronounced with activated macrophages, whether C. albicans was opsonized or unopsonized and ingested through the macrophage mannose receptor. rhMPO did not affect the killing of C. albicans by monocytes, nor did it affect phagocytosis of opsonized or unopsonized C. albicans. These results indicate that exogenous rhMPO can augment the candidacidal capacity of both resident and activated macrophages, with a more profound effect on activated cells. We suggest that rhMPO may be effective in the treatment of invasive candidiasis.  相似文献   

3.
Amenability of emergency service physician for the treatment given without patient consent has been presented in the study. Depending on circumstances it can be penal, civil, disciplinary and professional responsibility. The study has been annotated with current legal and ethical rules, which should be not only commonly known to physicians but also respected to avoid legal consequences.  相似文献   

4.
G-CSF and GM-CSF have been shown in each clinical setting to reduce the duration of neutropenia, with the exception of the scant data available in the unrelated bone marrow transplant setting. These growth factors also have been shown to have no leukemogenic effect during the observation periods of the trials discussed. In MDS, one major randomized trial has demonstrated a reduction in incidence of infection. This has not yet been demonstrated in AML and allogeneic BMT. Data from ongoing and future trials will be helpful in elucidating their effect on treatment-related morbidity and overall survival.  相似文献   

5.
Mutation of the granulocyte-macrophage colony-stimulating factor (GM-CSF) gene by homologous recombination causes progressive pulmonary alveolar proteinosis (PAP) in GM-CSF-deficient mice (GM-/-). The present study tested whether adenovirus-mediated expression of GM-CSF alters the progression of PAP in GM-/- mice. Adult mice were pretreated with an anti-T cell receptor (TCR) antibody to block T cell-mediated immune response, followed by intratracheal instillation of deltaE1-E3 replication-deficient adenovirus expressing mouse GM-CSF (Av1mGM). Mice were killed 1, 3, and 5 weeks after treatment to assess lungs for GM-CSF, surfactant protein B (SP-B), alveolar macrophage maturation, and type II cell proliferation. GM-CSF was detected in BAL fluid from GM-/- mice 1 week after Av1mGM treatment, and GM-CSF mRNA was detected by RT-PCR through 5 weeks. Five weeks after Av1mGM treatment, PAP was improved and SP-B decreased as assessed by ELISA and immunostaining. Increased numbers of alveolar macrophages stained with alpha-naphthyl acetate esterase (alpha-NAE) following treatment with Av1mGM. Local expression of GM-CSF with a recombinant adenovirus ameliorated PAP in the GM-/- mice in association with enhanced maturation of alveolar macrophages.  相似文献   

6.
To explore the role of perfectionism across anxiety disorders, 175 patients with either panic disorder (PD), obsessive compulsive disorder (OCD), social phobia, or specific phobia, as well as 49 nonclinical volunteers, completed two measures [Frost, R. O., Marten, P., Lahart, C., & Rosenblate, R., (1990). The dimensions of perfectionism. Cognitive Therapy and Research, 14, 449-468; Hewitt, P. L., & Flett, G. L., (1991). Perfectionism in the self and social contexts: Conceptualization, assessment and association with psychopathology. Journal of Personality and Social Psychology, 60, 456-470.] that assess a total of nine different dimensions of perfectionism. Relative to the other groups, social phobia was associated with greater concern about mistakes (CM), doubts about actions (DA), and parental criticism (PC) on one measure and more socially prescribed perfectionism (SP) on the other measure. OCD was associated with elevated DA scores relative to the other groups. PD was associated with moderate elevations on the CM and DA subscales. The remaining dimensions of perfectionism failed to differentiate among groups. The clinical implications of these findings are discussed.  相似文献   

7.
Neutral endopeptidase 24.11 (NEP/CALLA/CD10), an enzyme expressed on early lymphoid progenitors, neutrophils, and various other cell types, inactivates many biologically active peptides, including the bacterial chemotactic peptide N-formylmethionyl-leucyl-phenylalanine (fMLP). Inhibition of CD10/NEP on the surface of human neutrophils (PMNs) in vitro inhibits migration toward this chemotaxin, suggesting that enzymatic inactivation by NEP regulates the neutrophil response to fMLP. Because PMNs in inflammatory sites are exposed to various cytokines, we evaluated the effects of selected cytokines on CD10/NEP activity in vitro. Of five cytokines tested--interleukin-1 (IL-1), IL-6, and IL-8, granulocyte colony-stimulating factor, and granulocyte-macrophage colony-stimulating factor (GM-CSF)--GM-CSF provided the most consistent increase in surface NEP activity. Low concentrations (10(-9)-10(-7) M) of GM-CSF increased NEP activity in a time- and concentration-dependent manner to more than 225% that of control (phosphate-buffered saline-treated) cells. Cytofluorometry of cells stained with a fluorescent antibody to CD10 indicated that GM-CSF increased expression of surface CD10/NEP antigen in a similar manner. The effect of GM-CSF on NEP activity was enhanced still further by simultaneous exposure to IL-1, suggesting that combinations of cytokines may direct and regulate the neutrophil response within an inflammatory site. Rapid upregulation of CD10/NEP underscores the importance of this enzyme for control of peptide mediators of inflammation.  相似文献   

8.
Human granulocyte-macrophage colony-stimulating factor (GM-CSF) stimulates the proliferation and maturation of normal myeloid progenitor cells and can also stimulate the growth of acute myelogenous leukemia (AML) blasts. GM-CSF is not normally produced by resting cells but is expressed by a variety of activated cells including T lymphocytes, macrophages, and certain cytokine-stimulated fibroblasts and endothelial cells. Production of GM-CSF by cultured AML cells has been demonstrated, and GM-CSF expression by normal myeloid progenitors has been postulated to play a role in myelopoiesis. We have investigated the regulation of expression of GM-CSF in AML cell lines, and our results demonstrate the presence of a strong constitutive promoter element contained within 53 bp upstream of the cap site. We have also identified a negative regulatory element located immediately upstream of the positive regulatory element (within 69 bp of the cap site) that is active in AML cell lines but not T cells or K562 CML cells. Competition transfection and mobility shift studies demonstrate that this activity correlates with binding of a 45-kDa protein.  相似文献   

9.
10.
Smooth muscle cells (SMC) are the major cell type found in the walls of large blood vessels and appear to participate in local immune and inflammatory reactions, as well as in certain vascular diseases. We tested whether human arterial SMC can produce in vitro the colony stimulating factors (CSFs), granulocyte macrophage-CSF (GM-CSF) and macrophage CSF (M-CSF). Untreated internal mammary artery and aortic SMC produced no detectable GM-CSF but constitutively made M-CSF, measured by ELISA and radioimmunoassay, respectively. Interleukin-1 (IL-1) and, to a lesser extent, tumor necrosis factor alpha (TNF alpha) stimulated GM-CSF formation within 3 h; mRNA levels also increased particularly in the presence of the protein synthesis inhibitor, cycloheximide. IL-1, TNF alpha and, in addition, interferon-gamma (IFN-gamma) raised the M-CSF levels within 6 h; cycloheximide potentiated the effects of IL-1 and TNF alpha on mRNA levels. These results suggest that cytokine-stimulated human arterial SMC may be a source of the M-CSF found in atherosclerotic lesions. Since monocytes/macrophages can be activated by GM-CSF and M-CSF, while GM-CSF can also affect granulocyte function, SMC may participate in inflammatory reactions and vascular diseases by releasing these cytokines.  相似文献   

11.
Clinical outcomes of 95 second-trimester fetuses prospectively considered to have echogenic bowel at ultrasound were compared with a control group of 110 consecutive second-trimester fetuses. Among the 95 fetuses in the study group, 64 (67%) had moderately echogenic (grade 2) or markedly echogenic (grade 3) bowel relative to the liver. Among the 110 fetuses in the control group, only two (1.8%) had moderately echogenic (grade 2) bowel; the rest (98.2%) had isoechoic (grade 0) or midly echogenic (grade 1) bowel relative to the liver. Adverse outcomes occurred in 45 of the 95 fetuses (47%) with echogenic bowel compared with eight of the 110 fetuses (7.27%) in the control group (P < .01; relative risk, 6.5; 95% confidence interval, 3.2, 13.1). Adverse outcomes included chromosomal abnormalities, intrauterine growth retardation, fetal demise, or other fetal anomalies. Within the study group, adverse outcomes occurred in 40 of the 64 fetuses (62%) with grade 2 or 3 bowel echogenicity, compared with five of the 31 fetuses (16%) with grade 1 echogenicity. Echogenic bowel is associated with an increased risk of adverse fetal outcome and this risk is confined primarily to grades 2 and 3 echogenicity.  相似文献   

12.
A comprehensive review of ultrasonography of the knee is presented and includes the choice of equipment and best patient positioning as well as a review of the normal anatomy and major disorders involving the knee, menisci and ligaments.  相似文献   

13.
We tested the influence of in vivo volume resuscitation on intrinsic contractile properties of left ventricular (LV) preparations of endotoxemic guinea pigs. Escherichia coli endotoxin (LPS)-injected animals were divided into nonresuscitated and resuscitated groups. Volume resuscitation improved cardiac output and stroke volume, increased arterial pH and body temperature, and decreased mortality. In isovolumetric LV preparations isolated 4 h after LPS injection, LV systolic pressures (in mmHg) preparations isolated 4 h after LPS injection, LV systolic pressures (in mmHg) of LPS with (42 +/- 3) and without (42 +/- 2) fluid resuscitation were consistently less than control values (70 +/- 3). LV end-diastolic pressure-volume (compliance) decreased in LPS-nonresuscitated hearts, while LV compliance of LPS-resuscitated hearts was similar to control. Thus, intravascular volume expansion selectively improved LV diastolic compliance of LPS hearts without affecting LV systolic function. These findings suggest that LV systolic and diastolic dysfunctions associated with endotoxemia and Gram-negative sepsis may involve separate pathogenic mechanisms.  相似文献   

14.
To clarify the differences of the signaling pathways used by granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF), and tumor necrosis factor- (TNF), we investigated activation of mitogen-activated protein kinase (MAPK) subtype cascades in human neutrophils stimulated by these cytokines. G-CSF exclusively tyrosine-phosphorylated extracellular signal-regulated kinase (ERK). GM-CSF tyrosine-phosphorylated ERK strongly and p38 MAPK weakly, whereas TNF tyrosine-phosphorylated p38 MAPK strongly and ERK weakly. Consistent with these findings, MEK, an upstream kinase of ERK, was phosphorylated by G-CSF, GM-CSF, and TNF, whereas MKK3/MKK6, an upstream kinase of p38 MAPK, was phosphorylated by GM-CSF and TNF, but not by G-CSF. The potency of these cytokines to phosphorylate ERK and MEK was GM-CSF > G-CSF > TNF, whereas that to phosphorylate p38 MAPK and MKK3/MKK6 was TNF > GM-CSF. C-Jun amino-terminal kinase (JNK) was not tyrosine-phosphorylated by any cytokine despite the existence of JNK proteins in human neutrophils, whereas it was tyrosine-phosphorylated by TNF in undifferentiated and all-trans retinoic acid-differentiated HL-60 cells. Increased phosphorylation of ERK or p38 MAPK was detected within 1 to 5 minutes after stimulation with each cytokine and was dependent on the concentrations of cytokines used. MEK inhibitor (PD98059) reduced tyrosine phosphorylation of ERK, but not p38 MAPK, induced by G-CSF, GM-CSF, or TNF. GM-CSF- or TNF-induced superoxide (O2-) release was inhibited by p38 MAPK inhibitor (SB203580) in a dose-dependent manner, suggesting the possible involvement of p38 MAPK in GM-CSF- or TNF-induced O2- release. The results indicate that G-CSF, GM-CSF, and TNF activate the overlapping but distinct MAPK subtype cascades in human neutrophils and suggest that the differential activation of ERK and p38 MAPK cascades may explain the differences of the effects of these cytokines on human neutrophil functions.  相似文献   

15.
16.
Using a clonal assay of bone marrow (BM) cells from transgenic mice (Tg-mice) expressing the human granulocyte-macrophage colony-stimulating factor receptor (hGM-CSFR), we found in earlier studies that hGM-CSF alone supported the development not only of granulocyte-macrophage colonies, but also of erythrocytes, megakaryocytes, mast cells, blast cells, and mixed hematopoietic colonies. In this report, we evaluated the in vivo effects of hGM-CSF on hematopoietic and lymphopoietic responses in the hGM-CSFR Tg-mice. Administration of this factor to Tg-mice resulted in dose-dependent increases in numbers of reticulocytes and white blood cells (WBCs) in the peripheral blood. Morphological analysis of WBCs showed that the numbers of all types of the cell, including neutrophils, eosinophils, monocytes, and lymphocytes increased; the most remarkable being in lymphocytes that contained a number of large granular lymphocytes (LGLs) in addition to mature T and B cells. However, total cellularity of the BM of the Tg-mice decreased in a dose-dependent manner when hGM-CSF was injected. In sharp contrast to the BM, spleens of the Tg-mice were grossly enlarged. Although all types of blood cells and hematopoietic progenitors increased in the spleen, erythroid cells and their progenitors showed the most significant increase. Increased numbers of megakaryocytes and LGLs were also observed in spleen and liver of the treated Tg-mice. Flow cytometric analysis showed that LGLs expanded in Tg-mice expressed Mac-1+ CD3- NK1.1+. The thymus of Tg-mice treated with hGM-CSF exhibited a dose-dependent shrinkage and a remarkable decrease in CD4+ CD8+ cells. Thus, hGM-CSF stimulated not only myelopoiesis but also erythropoiesis and megakaryopoiesis of hGM-CSFR Tg-mice in vivo, in accordance with our reported in vitro findings. In addition, hGM-CSF affected the development of lymphoid cells, including natural killer cells of these Tg-mice.  相似文献   

17.
Three new species of Eimeria are described from iguanid lizards of Central and South America. The oocysts of each species have no micropyles or residua and the sporocysts lack Stieda bodies, but all have a sporocyst residuum. Eimeria sanctaluciae n.sp. was found in the St. Lucia tree lizard, Anolis luciae, collected from the Maria Islands, Lesser Antilles. The oocysts are spherical to subspherical, averaging 17.3 x 16.5 microns, with a single layered colourless wall; about 60% contain polar granules. The sporocysts are ellipsoidal and average 7.7 x 5.5 microns. Eimeria liolaemi n.sp. was recovered from the blue-gold swift, Liolaemus taenius, from Chile. The oocysts are spherical to subspherical, measuring 21 x 20.1 microns with a single-layered colourless wall. The sporocysts are subspherical and average 7.4 x 6.8 microns. Eimeria caesicia n.sp. is described from the Brazilian collared iguanid, Tropidurus torquatus. The oocysts measure 27.4 x 23.7 microns, are spherical to subspherical, with a bilayered wall, the outer surface of which appears pale blue in colour, the thin, inner wall appearing brown, when viewed by direct light under the optical microscope. The sporocysts are subspherical and average 9.4 x 7.2 microns. Unnamed polysporocystid oocysts with dizoic sporocysts are reported from the faeces of the lesser St. Vincent tree lizard, Anolis trinitatis and the possibility of spurious parasitism briefly discussed. In addition, oocysts of an unnamed Isospora sp. with a smooth oocyst wall which closely resembles I. reui were recovered from A. trinitatis.  相似文献   

18.
The hematopoietic cytokine granulocyte-macrophage colony-stimulating factor (GM-CSF) mediates its activity through binding to cell-surface receptors. The high-affinity GM-CSF receptor (GMR) consists of two transmembrane-anchored subunits: a ligand-specific, low-affinity subunit (GMRalpha); and a signal-transducing beta-subunit (GMRbeta). The human GMRalpha subunit also exists in a soluble isoform (SOLalpha) which antagonizes GM-CSF activity in vitro. Previous studies by us have shown that coexpression of SOLalpha and a mutated GMRbeta in BHK cells results in retention of SOLalpha on the cell surface and the formation of an intermediate affinity binding complex (Kd approximately 300 pM). This paper investigates the mechanism of the retention of SOLalpha on the cell surface. The data demonstrate that SOLalpha is anchored by a direct, ligand-independent interaction with GMRbeta which also occurs when SOLalpha is coexpressed with wild-type GMRbeta. However, SOLalpha and wild-type GMRbeta form a complex which binds GM-CSF with high affinity (Kd = 39 pM), indistinguishable from the binding characteristics of the TMalpha/GMRbeta complex. The experiments further reveal that the interaction between SOLalpha and GMRbeta is abrogated by removal of the unique 16 amino acid carboxyl-terminal domain of SOLalpha. Specific mutation of cysteine 323 in this carboxyl-domain to alanine also eliminates the cell-surface retention of SOLalpha identifying this residue as being necessary for the formation of the SOLalpha/GMRbeta complex.  相似文献   

19.
Voriconazole (VCZ) was tested for antifungal activity against Aspergillus fumigatus hyphae alone or in combination with neutrophils or monocytes. Antifungal activity was measured as percent inhibition of hyphal growth in assays using the dye MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] or XTT [2, 3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxa nilide ]. With both assays, VCZ inhibited hyphal growth at concentrations of <1 microgram/ml and was almost as active as amphotericin B. VCZ (0.6 microgram/ml) was sporicidal, as was amphotericin B (0.4 microgram/ml). With both the MTT and XTT assays, neutrophils alone inhibited hyphae; when combined with VCZ, there was additive activity. Both granulocyte colony-stimulating factor- and granulocyte-macrophage colony-stimulating factor (GM-CSF)-treated polymorphonuclear neutrophils (PMN) had enhanced inhibition of hyphal growth. Moreover, such treatment of PMN also enhanced the collaboration of PMN with VCZ. Monocytes inhibited hyphal growth. When VCZ was combined with monocytes or monocytes were treated with GM-CSF, inhibition was significantly increased, to similar levels. However, the combination of VCZ with GM-CSF treatment of monocytes did not significantly increase the high-level inhibition by monocytes with either agent alone.  相似文献   

20.
In vitro pretreatment of human mononuclear blood cells with a combination of interleukin-2 and interleukin-4 decreases corticosteroid receptor affinity and reduces the anti-proliferative effects of corticosteroids. Similar abnormalities have been observed in mononuclear blood cells of steroid-resistant asthmatics. In vitro steroid resistance was induced by 48 h pretreatment of mononuclear blood cells from healthy individuals (n = 10) with interleukin-2 and interleukin-4 (500 Units (U)/ml). The effects of three structurally different corticosteroids (10(-7)-10(-11) M) on lipopolysaccharide-stimulated (10 ng/ml; 20 h) production of granulocyte-macrophage colony-stimulating factor (GM-CSF) were examined. GM-CSF production was efficiently inhibited by all three corticosteroids in the control cultures. Cortivazol was significantly more potent (IC50 = 3 x 10(-11) M) than budesonide and tipredane (IC50 = 2.5 x 10(-10) M and IC50 = 2 x 10(-10) M, respectively). However. interleukin-2 and interleukin-4 pretreatment counteracted the inhibitory effects of all three corticosteroids to a similar degree. The results highlight the importance of interleukin-2 and interleukin-4 in the induction of steroid resistance, since pretreatment of mononuclear blood cells with these cytokines impaired corticosteroid inhibition of GM-CSF production.  相似文献   

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