Effect of low-dose prednisone in vivo on the ability of complement receptor to mediate an oxidative burst in rat neutrophils

2000 ◽  
Vol 49 (3) ◽  
pp. 247-254 ◽  
Author(s):  
Cleni M Marzocchi-Machado ◽  
Elisa Maria S Russo ◽  
Celene Maria O.S Alves ◽  
Ana Cristina M Polizello ◽  
Ana Elisa C.S Azzolini ◽  
...  
Keyword(s):  
Oxidative Burst ◽  
Low Dose ◽  
Complement Receptor ◽  
Dose Prednisone

Investigation of the Interaction of Blood Platelets with the Coagulation System at the Site of Plug Formation In Vivo in Man - Effect of Low-Dose Aspirin

1987 ◽  
Vol 57 (01) ◽  
pp. 062-066 ◽  
Author(s):  
P A Kyrle ◽  
J Westwick ◽  
M F Scully ◽  
V V Kakkar ◽  
G P Lewis
Keyword(s):  
Platelet Activation ◽  
Thrombin Generation ◽  
Low Dose ◽  
Bleeding Time ◽  
Blood Platelets ◽  
Dose Aspirin ◽  
Low Dose Aspirin ◽  
Plug Formation ◽  
Granule Release

SummaryIn 7 healthy volunteers, formation of thrombin (represented by fibrinopeptide A (FPA) generation, α-granule release (represented by β-thromboglobulin [βTG] release) and the generation of thromboxane B2 (TxB2) were measured in vivo in blood emerging from a template bleeding time incision. At the site of plug formation, considerable platelet activation and thrombin generation were seen within the first minute, as indicated by a 110-fold, 50-fold and 30-fold increase of FPA, TxB2 and PTG over the corresponding plasma values. After a further increase of the markers in the subsequent 3 minutes, they reached a plateau during the fourth and fifth minute. A low-dose aspirin regimen (0.42 mg.kg-1.day-1 for 7 days) caused >90% inhibition of TxB2formation in both bleeding time blood and clotted blood. At the site of plug formation, a-granule release was substantially reduced within the first three minutes and thrombin generation was similarly inhibited. We conclude that (a) marked platelet activation and considerable thrombin generation occur in the early stages.of haemostasis, (b) α-granule release in vivo is partially dependent upon cyclo-oxygenase-controlled mechanisms and (c) thrombin generation at the site of plug formation is promoted by the activation of platelets.

Increased Thromboxane Biosynthesis in Essential Thrombocythemia

1995 ◽  
Vol 74 (05) ◽  
pp. 1225-1230 ◽  
Author(s):  
Bianca Rocca ◽  
Giovanni Ciabattoni ◽  
Raffaele Tartaglione ◽  
Sergio Cortelazzo ◽  
Tiziano Barbui ◽  
...  
Keyword(s):  
Platelet Count ◽  
Platelet Activation ◽  
Essential Thrombocythemia ◽  
Therapeutic Strategy ◽  
Low Dose ◽  
Thrombotic Risk ◽  
Dose Aspirin ◽  
Gender And Age ◽  
Low Dose Aspirin

SummaryIn order to investigate the in vivo thromboxane (TX) biosynthesis in essential thromboeythemia (ET), we measured the urinary exeretion of the major enzymatic metabolites of TXB2, 11-dehydro-TXB2 and 2,3-dinor-TXB2 in 40 ET patients as well as in 26 gender- and age-matched controls. Urinary 11-dehydro-TXB2 was significantly higher (p <0.001) in thrombocythemic patients (4,063 ± 3,408 pg/mg creatinine; mean ± SD) than in controls (504 ± 267 pg/mg creatinine), with 34 patients (85%) having 11-dehydro-TXB2 >2 SD above the control mean. Patients with platelet number <1,000 × 109/1 (n = 25) had significantly higher (p <0.05) 11 -dehydro-TXB2 excretion than patients with higher platelet count (4,765 ± 3,870 pg/mg creatinine, n = 25, versus 2,279 ± 1,874 pg/mg creatinine, n = 15). Average excretion values of patients aging >55 was significantly higher than in the younger group (4,784 ± 3,948 pg/mg creatinine, n = 24, versus 2,405 ± 1,885 pg/mg creatinine, n = 16, p <0.05). Low-dose aspirin (50 mg/d for 7 days) largely suppressed 11-dehydro-TXB2 excretion in 7 thrombocythemic patients, thus suggesting that platelets were the main source of enhanced TXA2 biosynthesis. The platelet count-corrected 11-dehydro-TXB2 excretion was positively correlated with age (r = 0.325, n = 40, p <0.05) and inversely correlated with platelet count (r = -0.381, n = 40, p <0.05). In addition 11 out of 13 (85%) patients having increased count-corrected 11-dehydro-TXB2 excretion, belonged to the subgroup with age >55 and platelet count <1,000 × 1099/1. We conclude that in essential thrombocythemia: 1) enhanced 11-dehydro-TXB2 excretion largely reflects platelet activation in vivo;2) age as well as platelet count appear to influence the determinants of platelet activation in this setting, and can help in assessing the thrombotic risk and therapeutic strategy in individual patients.

Ciamexon in low-dose streptozotocin induced diabetes mellitus. In vivo and in vitro studies

1986 ◽  
Vol 113 (1_Suppl) ◽  
pp. S120-S121
Author(s):  
TH. LINN ◽  
H. GERMANN ◽  
B. HERING ◽  
R. BRETZEL ◽  
K. FEDERLIN
Keyword(s):  
Diabetes Mellitus ◽  
Low Dose ◽  
In Vitro Studies ◽  
Streptozotocin Induced Diabetes

Increased Circulatory Extrarenal 1α,25-Dihydroxyvitamin D3 in Bilaterally Nephrectomized Rats

2020 ◽  
Vol 20 (9) ◽  
pp. 1523-1530
Author(s):  
Murat Dabak ◽  
Durrin O. Dabak ◽  
Tuncay Kuloglu ◽  
Ersoy Baydar ◽  
Hakan Bulut ◽  
...  
Keyword(s):  
Immune Cells ◽  
Low Dose ◽  
Systemic Circulation ◽  
Bilateral Nephrectomy ◽  
Dihydroxyvitamin D3 ◽  
Hydroxyvitamin D ◽  
Inflammatory Conditions ◽  
Calcium Phosphorus ◽  
25 Hydroxyvitamin D

Background: Extrarenal 1α,25-dihydroxyvitamin D3 (1,25-D) locally produced by immune cells plays crucial roles in the regulation of the immune system. However, in vivo status of extrarenal 1,25-D and 25-hydroxyvitamin D (25-D) in acute inflammatory conditions are unknown. Objective: The aim of this study was to determine the extrarenal 1,25-D level in circulation in bilaterally nephrectomized rats, induced by low-dose lipopolysaccharide (LPS). Methods: Renal 1,25-D synthesis was terminated through bilateral nephrectomy in rats. The rats received intraperitoneal LPS (50 μg/kg BW) three times and the experiment was ended 24 hours after nephrectomy. Serum 1,25-D, 25-D, calcium, phosphorus, intact parathyroid hormone, and calcitonin levels were measured and immunohistochemistry was applied to detect the sources of extrarenal 1,25- D synthesis. Results: Circulatory 1,25-D concentration remarkably increased in both LPS-treated and non-treated bilaterally nephrectomized rats. Elevated circulatory 1,25-D did not have hypercalcemic endocrinal effects. The increased 1,25-D level also resulted in a concurrent rapid and dramatic depletion of circulatory 25-D. Conclusions: Extrarenal 1,25-D could enter into the systemic circulation and, therefore, might have systemic effects besides its autocrine and paracrine functions.

Rapid in vivo induction of leukocyte tissue factor mRNA and protein synthesis following low dose endotoxin administration to rabbits

2001 ◽  
Vol 2 (3) ◽  
pp. 188-195 ◽  
Author(s):  
Tara C Brutzki ◽  
Myron J Kulczycky ◽  
Leslie Bardossy ◽  
Bryan J Clarke ◽  
Morris A Blajchman
Keyword(s):  
Protein Synthesis ◽  
Tissue Factor ◽  
Low Dose ◽  
Endotoxin Administration ◽  
In Vivo Induction

scholarly journals Spatio-temporal biodistribution of 89Zr-oxine labeled huLym-1-A-BB3z-CAR T-cells by PET imaging in a preclinical tumor model

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Naomi S. Sta Maria ◽  
Leslie A. Khawli ◽  
Vyshnavi Pachipulusu ◽  
Sharon W. Lin ◽  
Long Zheng ◽  
...  
Keyword(s):  
T Cells ◽  
Real Time ◽  
Pet Imaging ◽  
Dose Group ◽  
Low Dose ◽  
High Dose ◽  
Car T Cells ◽  
Nsg Mice ◽  
Car T

AbstractQuantitative in vivo monitoring of cell biodistribution offers assessment of treatment efficacy in real-time and can provide guidance for further optimization of chimeric antigen receptor (CAR) modified cell therapy. We evaluated the utility of a non-invasive, serial 89Zr-oxine PET imaging to assess optimal dosing for huLym-1-A-BB3z-CAR T-cell directed to Lym-1-positive Raji lymphoma xenograft in NOD Scid-IL2Rgammanull (NSG) mice. In vitro experiments showed no detrimental effects in cell health and function following 89Zr-oxine labeling. In vivo experiments employed simultaneous PET/MRI of Raji-bearing NSG mice on day 0 (3 h), 1, 2, and 5 after intravenous administration of low (1.87 ± 0.04 × 106 cells), middle (7.14 ± 0.45 × 106 cells), or high (16.83 ± 0.41 × 106 cells) cell dose. Biodistribution (%ID/g) in regions of interests defined over T1-weighted MRI, such as blood, bone, brain, liver, lungs, spleen, and tumor, were analyzed from PET images. Escalating doses of CAR T-cells resulted in dose-dependent %ID/g biodistributions in all regions. Middle and High dose groups showed significantly higher tumor %ID/g compared to Low dose group on day 2. Tumor-to-blood ratios showed the enhanced extravascular tumor uptake by day 2 in the Low dose group, while the Middle dose showed significant tumor accumulation starting on day 1 up to day 5. From these data obtained over time, it is apparent that intravenously administered CAR T-cells become trapped in the lung for 3–5 h and then migrate to the liver and spleen for up to 2–3 days. This surprising biodistribution data may be responsible for the inactivation of these cells before targeting solid tumors. Ex vivo biodistributions confirmed in vivo PET-derived biodistributions. According to these studies, we conclude that in vivo serial PET imaging with 89Zr-oxine labeled CAR T-cells provides real-time monitoring of biodistributions crucial for interpreting efficacy and guiding treatment in patient care.

Nonprotein sulfhydryl compounds in canine gastric mucosa: effects of PGE2 and ethanol

1985 ◽  
Vol 249 (1) ◽  
pp. G137-G144 ◽  
Author(s):  
T. A. Miller ◽  
D. Li ◽  
Y. J. Kuo ◽  
K. L. Schmidt ◽  
L. L. Shanbour
Keyword(s):  
Gastric Mucosa ◽  
Low Dose ◽  
Mucosal Damage ◽  
Gastric Mucosal Damage ◽  
High Dose ◽  
Mucosal Protection ◽  
Gastric Mucosal Protection ◽  
Sulfhydryl Compounds ◽  
Mild Irritants

By use of an in vivo canine chambered stomach preparation in which the gastric mucosa was partitioned into two equal halves, the effect of topical 16,16-dimethyl PGE2 (DMPGE2) (1 microgram/ml of perfusate) and 8% and 40% ethanol on tissue levels of nonprotein sulfhydryl compounds was assessed. Both DMPGE2 and 8% ethanol significantly increased (P less than 0.005) mucosal levels of nonprotein sulfhydryls when compared with corresponding mucosa bathed with saline alone. In contrast, mucosa bathed with 40% ethanol showed significantly decreased levels. If mucosa was bathed with DMPGE2 or 8% ethanol prior to exposing the stomach to 40% ethanol, this depletion in sulfhydryl compounds was not observed. Since other experimental observations have shown that exogenously administered prostaglandins and mild irritants (such as low-dose alcohol) can prevent gastric mucosal damage by necrotizing agents (such as high-dose alcohol), our findings are consistent with the hypothesis that nonprotein sulfhydryls may play a role in mediating gastric mucosal protection.

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