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Publication
Journal: Journal of Urology
April/20/1997
Abstract
OBJECTIVE
We tested the hypothesis that certain patients with hormone refractory prostate cancer retain hormonal sensitivity even after progression following antiandrogen withdrawal. The efficacy of ketoconazole and hydrocortisone in this patient population was evaluated.
METHODS
A total of 50 consecutive patients with advanced prostate cancer received ketoconazole and hydrocortisone at progression after antiandrogen withdrawal. Prostate specific antigen (PSA) response was defined as greater than a 50% decrease in PSA from baseline that was maintained for at least 8 weeks.
RESULTS
Overall, of 48 evaluable patients 30 (62.5%, 95% confidence interval 47.3 to 76.1%) had greater than a 50% decrease in PSA, while 23 (48%) had greater than an 80% decrease. The median duration of response was 3.5 months but 23 of 48 patients continue to exhibit a response, ranging from 3.25 to 12.75 or more months. The ketoconazole response rate in patients with no response to prior antiandrogen withdrawal was not different from that in patients with such a response (65 versus 40%, p = 0.35). Toxicity was mild. Grade 1 or 2 nausea, fatigue, edema, hepatotoxicity and rash occurred in 10.4 (5 of 48), 6.25, 6.25, 4.2 and 4.2% of patients, respectively, and anorexia occurred in 2%.
CONCLUSIONS
Failure to respond to antiandrogen withdrawal does not identify patients with truly hormone refractory disease. Ketoconazole retains significant activity in this setting and is extremely well tolerated.
Publication
Journal: British Journal of Pharmacology
July/6/1992
Abstract
Incubation of vascular endothelial cells with S.typhosa endotoxin and interferon-gamma caused a time- and concentration-dependent reduction in the viability of the cells. The cytotoxic effect was inhibited in a concentration-dependent manner by NG-monomethyl-L-arginine, an inhibitor of nitric oxide (NO) synthesis, and by the glucocorticoids dexamethasone and hydrocortisone, two inhibitors of the induction of NO synthase. These findings indicate that in these cells the cytotoxic effect of endotoxin is mediated by the NO synthesized by an inducible NO synthase. This induction of NO synthase in vascular endothelial cells may represent a mechanism of local endothelial damage during endotoxin shock and other immunologically based conditions.
Publication
Journal: Journal of Experimental Medicine
July/17/1975
Abstract
A new and sensitive assay for the effect of intracutanous administration of immunocompentent lymphocytes into the skin of irradiated unimmunized mice is described. The assay, which we have termed lymphocyte-induced angiogenesis (LIA) involves enumeration of new vascular branches induced by the action of these competent cells. As is the case for the previously described normal lymphocyte transfer reaction, LIA is a manifestation of the graft-vs.-host reaction, as shown by experiments utilizing appropaiate genetic combinations. The reaction is dose-dependent, and within the dose range of 2 times 10 minus 5 -4 times 10-6 cells the mumber of vessels induced correlates with the mumber of immunocompetent cells injected. At these dose levels spleen, lumph node, and hydrocortisone-resistant thymocytes are effective; bone marrow and thymus cells are not. Spleen cells from nude mice are incapable of inducing LIA, while mitomycin-C and irradiated lymphocytes can initiate but not maintain the reaction. The relationship between lymphocyte-induced angiogenesis has been discussed as have the implications of these findings to delayed hypersensitivity, inflammation, and vascular pathology.
Publication
Journal: Intensive Care Medicine
January/7/2010
Abstract
BACKGROUND
Use of etomidate in the critically ill is controversial due to its links with an inadequate response to corticotropin and potential for excess mortality. In a septic shock population, we tested the hypotheses that etomidate administration induces more non-responders to corticotropin and increases mortality and that hydrocortisone treatment decreases mortality in patients receiving etomidate.
METHODS
An a-priori sub-study of the CORTICUS multi-centre, randomised, double-blind, placebo-controlled trial of hydrocortisone in septic shock. Use and timing of etomidate administration were collected. Endpoints were corticotropin response and all-cause 28-day mortality in patients receiving etomidate.
RESULTS
Five hundred patients were recruited, of whom 499 were analysable; 96 (19.2%) were administered etomidate within the 72 h prior to inclusion. The proportion of non-responders to corticotropin was significantly higher in patients who were given etomidate in the 72 h before trial inclusion than in other patients (61.0 vs. 44.6%, P = 0.004). Etomidate therapy was associated with a higher 28-day mortality in univariate analysis (P = 0.02) and after correction for severity of illness (42.7 vs. 30.5%; P = 0.06 and P = 0.03) in our two multi-variant models. Hydrocortisone administration did not change the mortality of patients receiving etomidate (45 vs. 40%).
CONCLUSIONS
The use of bolus dose etomidate in the 72 h before study inclusion is associated with an increased incidence of inadequate response to corticotropin, but is also likely to be associated with an increase in mortality. We recommend clinicians demonstrate extreme caution in the use of etomidate in critically ill patients with septic shock.
Publication
Journal: Hepatology
November/29/2006
Abstract
Relative adrenal insufficiency is frequent in patients with severe sepsis and is associated with hemodynamic instability, renal failure, and increased mortality. This study prospectively evaluated the effects of steroids on shock resolution and hospital survival in a series of 25 consecutive patients with cirrhosis and septic shock (group 1). Adrenal function was evaluated by the short corticotropin test within the first 24 hours of admission. Patients with adrenal insufficiency were treated with stress doses of intravenous hydrocortisone (50 mg/6 h). Data were compared to those obtained from the last 50 consecutive patients with cirrhosis and septic shock admitted to the same intensive care unit in whom adrenal function was not investigated and who did not receive treatment with steroids (group 2). Incidence of adrenal insufficiency in group 1 was 68% (17 patients). Adrenal dysfunction was frequent in patients with advanced cirrhosis (Child C: 76% vs. Child B: 25%, P = .08). Resolution of septic shock (96% vs. 58%, P = .001), survival in the intensive care unit (68% vs. 38%, P = .03), and hospital survival (64% vs. 32%, P = .003) were significantly higher in group 1. The main causes of death in group 1 were hepatorenal syndrome or liver failure (7 of 9 patients). In contrast, refractory shock caused most of the deaths in group 2 (20 of 34 patients). In conclusion, relative adrenal insufficiency is very frequent in patients with advanced cirrhosis and septic shock. Hydrocortisone administration in these patients is associated with a high frequency of shock resolution and high survival rate.
Publication
Journal: Journal of Cell Biology
June/13/1999
Abstract
Adherent epithelial cells require interactions with the extracellular matrix for their survival, though the mechanism is ill-defined. In long term cultures of primary mammary epithelial cells, a laminin-rich basement membrane (BM) but not collagen I suppresses apoptosis, indicating that adhesion survival signals are specific in their response (. J. Cell Sci. 109:631-642). We now demonstrate that the signal from BM is mediated by integrins and requires both the alpha6 and beta1 subunits. In addition, a hormonal signal from insulin or insulin-like growth factors, but not hydrocortisone or prolactin, is necessary to suppress mammary cell apoptosis, indicating that BM and soluble factors cooperate in survival signaling. Insulin induced autophosphorylation of its receptor whether mammary cells were cultured on collagen I or BM substrata. However, both the tyrosine phosphorylation of insulin receptor substrate-1 and its association with phosphatidylinositol 3-kinase were enhanced in cells cultured on BM, as was the phosphorylation of the phosphatidylinositol 3-kinase effector, protein kinase B. These results suggest a novel extracellular matrix-dependent restriction point in insulin signaling in mammary epithelial cells. The proximal signal transduction event of insulin receptor phosphorylation is not dependent on extracellular matrix, but the activation of downstream effectors requires adhesion to BM. Since phosphatidylinositol 3-kinase was required for mammary epithelial cell survival, we propose that a possible mechanism for BM-mediated suppression of apoptosis is through its facilitative effects on insulin signaling.
Publication
Journal: Archives of Disease in Childhood
October/13/1981
Abstract
Three newborn infants are reported who developed severe non-ketotic hypoglycaemia (blood glucose less than 1.1 mmol/l; 19.8 mg/100 ml) within 6 hours of birth. All had inappropriately raised plasma insulin concentrations for the level of glycaemia, and required high rates of glucose infusion (less than 15 mg glucose/kg per minute) to prevent symptoms of hypoglycaemia. Medical treatment (hydrocortisone, diazoxide, chlorothiazide, phenytoin, propranolol, and depot glucagon) was ineffective in preventing hypoglycaemia and all 3 infants were subjected to partial and then total pancreatectomy. The pathological features of nesidioblastosis are reported from quantitative immunohistochemical studies on the pancreata. These results together with those from metabolic and endocrine studies performed on the 3 infants during the investigation of the cause of the hypoglycaemia and during the preoperative and postoperative period are presented in detail in order to define a practical approach to the management of this difficult clinical problem in the neonate.
Publication
Journal: PLoS ONE
July/17/2011
Abstract
Targeting pro-inflammatory events to reduce seizures is gaining momentum. Experimentally, antagonism of inflammatory processes and of blood-brain barrier (BBB) damage has been demonstrated to be beneficial in reducing status epilepticus (SE). Clinically, a role of inflammation in the pathophysiology of drug resistant epilepsies is suspected. However, the use anti-inflammatory drug such as glucocorticosteroids (GCs) is limited to selected pediatric epileptic syndromes and spasms. Lack of animal data may be one of the reasons for the limited use of GCs in epilepsy. We evaluated the effect of the CG dexamethasone in reducing the onset and the severity of pilocarpine SE in rats. We assessed BBB integrity by measuring serum S100β and Evans Blue brain extravasation. Electrophysiological monitoring and hematologic measurements (WBCs and IL-1β) were performed. We reviewed the effect of add on dexamethasone treatment on a population of pediatric patients affected by drug resistant epilepsy. We excluded subjects affected by West, Landau-Kleffner or Lennox-Gastaut syndromes and Rasmussen encephalitis, known to respond to GCs or adrenocorticotropic hormone (ACTH). The effect of two additional GCs, methylprednisolone and hydrocortisone, was also reviewed in this population. When dexamethasone treatment preceded exposure to the convulsive agent pilocarpine, the number of rats developing status epilepticus (SE) was reduced. When SE developed, the time-to-onset was significantly delayed compared to pilocarpine alone and mortality associated with pilocarpine-SE was abolished. Dexamethasone significantly protected the BBB from damage. The clinical study included pediatric drug resistant epileptic subjects receiving add on GC treatments. Decreased seizure frequency (≥ 50%) or interruption of status epilepticus was observed in the majority of the subjects, regardless of the underlying pathology. Our experimental results point to a seizure-reducing effect of dexamethasone. The mechanism encompasses improvement of BBB integrity. Our results also suggest that add on GCs could be of efficacy in controlling pediatric drug resistant seizures.
Publication
Journal: Cancer
May/27/1996
Abstract
BACKGROUND
This retrospective study evaluates the results of a regimen of high-dose intrathecal methotrexate and the prognostic factors for the response in patients with meningeal from breast carcinoma.
METHODS
From 1979 to 1994, 68 breast carcinoma patients were diagnosed with meningeal carcinomatosis at a mean age of 52 years. All but two had previous metastatic involvement. The proportion of lobular and ductal carcinomas was balanced. Malignant cells were present in cerebrospinal fluid (CSF) samples from 61 patients, whereas the 7 remaining patients had increased CSF protein associated with computerized tomographic scan evidence of meningeal metastases. From 1989, 41 of the patients received a regimen of high-dose intrathecal methotrexate with systemic folinic acid rescue (HD-MTX+FA): intrathecal MTX, 15 mg daily x 5 days, repeated every 2 weeks, and intrathecal hydrocortisone acetate, 125 mg on Day 1, and folinic acid, 10 mg intramuscularly 12 hours after each MTX injection. Systemic treatment and radiation therapy were usually associated. Patients treated before 1988 received intrathecal MTX in conventional doses (15 mg once a week).
RESULTS
Clinical objective response, defined as a neurological improvement for at least one month, was achieved in 17 patients (41%) and stabilization in 14 (34%) treated with the HD-MTX+FA regimen. The response rate was significantly higher compared with that of the group treated with the conventional doses (P = 0.03). Median survival was 14 weeks for patients treated with the HD-MTX+FA regimen, compared with 7 weeks for patients who received conventional doses of MTX (P = 0.01). Grade 3 or 4 neutropenia was the main toxicity that occurred in 16 16 patients (39%) treated with the HD-MTX+FA regimen, and in 7 patients (33%) treated with conventional doses of MTX. In a univariate analysis, three parameters were singled out as having a favorable prognostic value for response to therapy; controlled systemic disease at diagnosis (P < 0.05), low initial CSF protein level (P < 0.05), and concomitant systemic chemotherapy during intrathecal therapy (P < 0.02). Multivariate analysis was not performed because the sample size was too small.
CONCLUSIONS
Although this study was retrospective, the intrathecal HD-MTX+FA regimen appears to be a more efficient strategy than conventional doses of MTX to induce neurologic improvement and perhaps better survival. It should be recommended in combination with systemic chemotherapy for selected patients with meningeal carcinomatosis from breast carcinoma who are likely to benefit from intensive therapy, i.e., patients with a CSF protein level less than 5 g/L and in whom systemic disease has been controlled.
Publication
Journal: American Journal of Respiratory Cell and Molecular Biology
April/22/1997
Abstract
Vascular endothelial growth factor (VEGF) is a potent peptide growth factor specific for vascular endothelial cells, which promotes neovascularization and increases vascular permeability in vivo. Enhanced microvascular permeability and edema are common characteristics of inflammatory and neoplastic disorders. Two proinflammatory mediators, platelet-activating factor (PAF) and platelet-derived growth factor (PDGF), are known to contribute to cellular damage and tissue remodeling in a number of lung diseases. To determine whether PAF or PDGF induce VEGF gene expression in primary cultures of human pulmonary fibroblasts and pulmonary vascular smooth-muscle cells (VSMCs), we performed Northern-blot analysis and enzyme-linked immunosorbent assays (EIA). PAF and all three isoforms of PDGF (PDGF-AA, -AB, and -BB) increased VEGF mRNA in a time- and dose-dependent manner. While PAF was shown to increase VEGF mRNA at picomolar concentrations, all PDGF isoforms were effective in inducing VEGF mRNA at nanomolar concentrations. The transcriptional activation was accompanied by increased levels of VEGF protein as determined by EIA in culture medium. These results indicate that VEGF gene expression in VSMCs and fibroblasts is mediated by PAF and/or PDGF isoforms. In a paracrine mode of action, secreted VEGF may then lead to altered endothelial cell functions and vascular hyperpermeability. In the presence of the corticosteroids cortisone, hydrocortisone, dexamethasone, or prednisolone at nanomolar concentrations, this stimulus-dependent transcription of VEGF was abolished. The inhibitory effect of corticosteroids on VEGF expression could explain the clinically well-known antiedematous potency of corticosteroids on a molecular level.
Publication
Journal: Proceedings of the National Academy of Sciences of the United States of America
August/19/1981
Abstract
Primary cultures of rat mammary epithelial cells proliferate and synthesize basement membrane collagen (type IV collagen) in a serum-free medium supplemented with epidermal growth factor (EGF), hydrocortisone or dexamethasone, insulin, transferrin, and Pedersen fetuin. The growth response of the cells to EGF and glucocorticoids but not to insulin or transferrin varies depending on the substratum on which the cells are plated. Cell growth is 4 times more sensitive to omission of EGF or glucocorticoid on type I collagen or plastic substratum than on type IV collagen substratum. The mechanism by which these two growth factors differentially affect cell growth appears to be linked to an increase in type IV collagen synthesis and a stabilization of secreted type IV collagen in the extracellular matrix. Glucocorticoids suppress the elaboration of type IV collagenolytic activity by the cells whereas EGF stimulates amino acid incorporation into type IV collagen. The results suggest that EGF and glucocorticoids affect mammary epithelial cell growth by facilitating the accumulation of the appropriate cell substratum.
Publication
Journal: Proceedings of the National Academy of Sciences of the United States of America
September/20/1995
Abstract
Nitric oxide synthesized by inducible nitric oxide synthase (iNOS) has been implicated as a mediator of inflammation in rheumatic and autoimmune diseases. We report that exposure of lipopolysaccharide-stimulated murine macrophages to therapeutic concentrations of aspirin (IC50 = 3 mM) and hydrocortisone (IC50 = 5 microM) inhibited the expression of iNOS and production of nitrite. In contrast, sodium salicylate (1-3 mM), indomethacin (5-20 microM), and acetaminophen (60-120 microM) had no significant effect on the production of nitrite at pharmacological concentrations. At suprapharmacological concentrations, sodium salicylate (IC50 = 20 mM) significantly inhibited nitrite production. Immunoblot analysis of iNOS expression in the presence of aspirin showed inhibition of iNOS expression (IC50 = 3 mM). Sodium salicylate variably inhibited iNOS expression (0-35%), whereas indomethacin had no effect. Furthermore, there was no significant effect of these nonsteroidal anti-inflammatory drugs on iNOS mRNA expression at pharmacological concentrations. The effect of aspirin was not due to inhibition of cyclooxygenase 2 because both aspirin and indomethacin inhibited prostaglandin E2 synthesis by>> 75%. Aspirin and N-acetylimidazole (an effective acetylating agent), but not sodium salicylate or indomethacin, also directly interfered with the catalytic activity of iNOS in cell-free extracts. These studies indicate that the inhibition of iNOS expression and function represents another mechanism of action for aspirin, if not for all aspirin-like drugs. The effects are exerted at the level of translational/posttranslational modification and directly on the catalytic activity of iNOS.
Publication
Journal: Journal of Clinical Investigation
November/21/1975
Abstract
To study the potential application of glucocorticosteroid administration for the measurement of the bone marrow neutrophil reserve response, blood neutrophil count changes were measured in normal subjects after the administration of intravenous hydrocortisone (25, 50, 100, 200, and 400 mg) and oral prednisone (5, 10, 20, 40, and 80 mg). The upper three doses of both steroids increased the blood neutrophil count by approximately 4,000 cells/mm3. The neutrophilia occurring after hydrocortisone (200 mg) and/or prednisone (40 mg) was compared with that observed after endotoxin (0.8 ng/kg) and etiocholanolone (0.1 mg/kg) in 14 normal subjects, 7 patients with Wegener's granulomatosis on cyclophosphamide therapy and 10 patients with chronic idiopathic neutropenia. The normal responses (mean increase of blood neutrophils/mm3 above base line +/- 1 SEM) were: hydrocortisone 4,220 +/- 320, prednisone 4,610 +/- 360, endotoxin 6,060 +/- 880, and etiocholanolone 3,780 +/- 440. In the patient studies, etiocholanolone gave the smallest mean responses, but, in general, the results were similar for all agents. These data indicate that these glucocorticosteroids can be used as equivalent agents to endotoxin and etiocholanolone for measuring the neutrophil reserve response.
Publication
Journal: Shock
November/9/2010
Abstract
Adhesion of polymorphonuclear neutrophils (PMN) to coronary endothelium is a key event for cardiac ischemia/reperfusion injury. Adhesion molecules are normally harbored within the glycocalyx, clothing every healthy vascular endothelium, but shed by ischemia/reperfusion. Our aim was to show whether protection of the glycocalyx with either hydrocortisone or antithrombin can reduce postischemic leukocyte adhesion. Isolated guinea pig hearts, perfused with Krebs-Henseleit buffer, were subjected to 20 min of warm (37 degrees C) no-flow ischemia and consecutive 10 min of reperfusion, either in the absence or presence of hydrocortisone (10 microg/mL) or antithrombin (1 U/mL). An intracoronary bolus of 3 x 10 PMN was applied at the end of reperfusion but without prior contact to the drugs. The sequestration of PMN was calculated from the difference between coronary input and output of cells. Expression of the integrin CD11b on PMN was measured before and after coronary passage. Ischemia/reperfusion induced severe degradation of the glycocalyx (coronary venous syndecan-1 release, 171 +/- 15 ng/g heart vs. basal, 19 +/- 2 ng/g; heparan sulfate, 5.27 +/- 0.28 microg/g vs. basal, 0.26 +/- 0.06 microg/g) and increased PMN adhesion (38.1% +/- 3.5% vs. basal, 11.7% +/- 3.1%). Hydrocortisone and antithrombin both not only reduced glycocalyx shedding (syndecan-1 release, 34 +/- 6 ng/g and 26 +/- 5 ng/g; heparan sulfate, 1.96 +/- 0.24 microg/g and 1.28 +/- 0.2 microg/g, respectively), but also PMN adhesion (17.3% +/- 2.2% and 25.4% +/- 3.3%, respectively) after ischemia/reperfusion. Electron microscopy revealed a mostly intact coronary glycocalyx after pretreatment with either drug. Activation of PMN upon coronary passage was not influenced. Preservation of the glycocalyx mitigates postischemic PMN adhesion. Preconditioning with either hydrocortisone or antithrombin should, thus, alleviate vascular leakage, tissue edema, and inflammation.
Publication
Journal: British Journal of Dermatology
February/28/2007
Abstract
BACKGROUND
Staphylococcus aureus has a peculiar ability to colonize the skin of patients with eczema and atopic dermatitis (AD), and is consistently found in eczematous skin lesions in these patients. A correlation between the severity of the eczema and colonization with S. aureus has been demonstrated, and it has been determined that bacterial colonization is an important factor aggravating skin lesions. Patients colonized with S. aureus have been treated with antibiotics in several open and double-blind placebo-controlled studies, with conflicting results.
OBJECTIVE
To investigate the colonizing features of S. aureus in the lesional and nonlesional skin of patients with eczema and AD in China and to compare the therapeutic effect of mupirocin plus hydrocortisone butyrate with vehicle ointment plus hydrocortisone butyrate.
METHODS
A multicentre, double-blind randomized trial was conducted. Eczema Area and Severity Index (EASI) scores were evaluated before the start of the trial and on the 7th, 14th and 28th day of treatment. Swabs for bacterial isolation were taken from lesional skin before the start of the trial and on the 7th, 14th and 28th day of treatment, and from nonlesional skin only before the start of the trial. A combination topical therapy with mupirocin plus hydrocortisone butyrate ointment was used in the experimental group, with vehicle ointment plus hydrocortisone butyrate ointment as a control.
RESULTS
Of 327 patients enrolled in the study, 208 had eczema and 119 had AD. Bacteria were isolated from 70.2% of lesional and 32.7% of nonlesional skin samples from patients with eczema, of which S. aureus accounted for 47.3% and 27.9%, respectively. Bacteria were isolated from 74.8% of lesional and 34.5% of nonlesional skin samples from patients with AD, of which S. aureus accounted for 79.8% and 80.5%, respectively. The colonization density of S. aureus was markedly higher in lesional than in nonlesional skin, both in patients with eczema and with AD (P < 0.01, P < 0.05), and was positively correlated with lesion severity. Considering the EASI scores before and after treatment and the final effective rate, good therapeutic effects were obtained in both the combination experimental groups and the control groups (P < 0.01), and there were no differences in the global therapeutic effect between the two groups in patients with eczema and with AD (P>> 0.05). However, in patients with eczema with a clinical score of>> 8 or in patients with AD with a clinical score of>> 7, the therapeutic effect in the experimental groups was superior to that in the control groups (P < 0.05) on the 7th day of treatment. There were no differences between the two groups on the 14th and 28th days of treatment (P>> 0.05). Following the improvement of symptoms and signs of eczema and AD, the positive rates of bacteria and S. aureus were reduced on the 7th day of treatment.
CONCLUSIONS
This study confirmed that lesional skin of patients with eczema and AD was more frequently colonized with S. aureus than was nonlesional skin. The more severe the eczema, the higher the colonization rate of S. aureus, and S. aureus was also more often present in lesional and nonlesional skin in patients with AD than in those with eczema. Staphylococcus aureus infection is related to the pathogenesis of eczema and AD. An antibiotic-corticosteroid combination and corticosteroid alone both gave good therapeutic effect in eczema and in AD, and both reduced colonization by S. aureus. Early combined topical therapy is beneficial to patients with moderate to severe eczema and AD, and it is unnecessary to use antibiotics at later stages of disease or in mild eczema or AD.
Authors
Publication
Journal: Journal of Clinical Investigation
August/11/1977
Abstract
Rabbit renomedullary interstitial cells were isolated and grown in tissue culture. These cells synthesize 0.8 ng of prostaglandin E2 (PGE2) per microgram cellular protein per hour in monolayer tissue culture; prostaglandins A2 and F2alpha (PGA2 and PGF2alpha) biosynthesis was 10 and 5% of PGE2 biosynthesis, respectively. Arachidonic acid markedly stimulated the production of PGE2 and PGF2alpha, with conversion rates of 0.24 and 0.02%/h, respectively. Angiotensin II, hyperosmolality, bradykinin, and arginine vasopressin each stimulated PGE2 biosynthesis; maximum stimulation was 20, 3.7, 3.6, and 3.2 times basal production, respectively. PGE2 biosynthesis by the renomedullary interstitial cells was inhibited by isoproterenol, potassium, nonsteroidal anti-inflammatory agents (indomethacin, naproxen, ibuprofen, suprofen, meclofenamate, and acetylsalicylic acid), mepacrine (a phospholipase inhibitor), hydrocortisone, and cortisone. The rabbit renomedullary interstitial cell in tissue culture is a model system for the study of hormonal regulation of PGE2 biosynthesis.
Publication
Journal: Science
May/30/1974
Abstract
The cytotoxic activity of activated macrophages against tumorigenic target cells appears to be mediated by lysosomal enzymes of activated macrophage origin. Lysosomes of activated macrophages are secreted directly into the cytoplasm of susceptible target cells, which subsequently undergo heterolysis. This reaction can be inhibited by agents which prevent the exocytosis of macrophage lysosomes (hydrocortisone) or which interfere with the action of lysosomal enzymes (trypan blue).
Authors
Publication
Journal: Journal of Neuroscience Research
January/5/1993
Abstract
Microglia, the resident macrophages of the brain, typically react to injuries or chronic diseases with proliferation and expression of differentiated features, such as production of cytokines associated with inflammatory events. Regulation and control of microglial cytokine expression, therefore, is a major focus of scientific interest. It has been shown that GMCSF and Il-3 are potent mitogens for microglia. Moreover, Il-3 and other cytokines are products of microglia. It is shown here that interleukin-1 (Il-1) as well as tumor necrosis factor (TNF alpha) increased microglial proliferation in mixed astrocyte-microglial cultures but had no mitogenic effects on isolated microglia. Lipopolysaccharide (LPS), the bacterial endotoxin, irreversibly inhibited microglial cell division in both mixed astrocyte-microglial cultures and in isolated microglial cultures. By contrast, the corticosteroids hydrocortisone and aldosterone and the synthetic glucocorticoid dexamethasone reversibly inhibited microglial proliferation. They also antagonized the stimulatory effects of Il-3 and granulocyte macrophage colony-stimulating factor (GMCSF). Estradiol and progesterone had no significant effects on mixed cultures but inhibited microglial proliferation in isolated cultures. Conditioned media from mixed cultures, isolated cultures, from the WEHI-2B cell line, or from fresh (serum-supplemented) media stimulated microglial proliferation to various extents. In summary, cytokine-mediated microglial proliferation can be down-regulated by a variety of steroid hormones. Along with their unimpaired access to brain cells in general, corticosteroids likely maintain an inhibitory tonus on microglial proliferation. It is hypothesized that this inhibition is overcome locally and temporally in brain injury and repair.
Publication
Journal: JAMA - Journal of the American Medical Association
April/30/2003
Authors
Publication
Journal: The American review of respiratory disease
April/25/1979
Abstract
Pneumocystis carinii organisms, isolated from lungs of rats with glucocorticoid-induced pneumocystosis, were ingested and degraded in vitro by alveolar and peritoneal macrophages obtained from healthy rats and mice. Uptake of the organisms was inhibited at 4 degrees C and by treatment of macrophages with iodoacetate. Neither uptake nor degradation was inhibited by pretreatment of macrophages with hydrocortisone sodium phosphate in vitro. Although peritoneal macrophages of any age in vitro were capable of ingesting Pneumocystis, alveolar macrophages that had been cultivated in vitro for less than 2 days were incapable of phagocytosis of the organism, a functional defect that corrected itself spontaneously during cultivation in vitro.
Publication
Journal: Journal of Clinical Investigation
September/10/1970
Abstract
Polymorphonuclear neutrophils (PMN) from patients with chronic granulomatous disease of childhood have impaired bactericidal activity and are deficient in diphosphopyridine nucleotide, reduced form of, (NADH) oxidase. Since hydrocortisone had been shown to inhibit NADH oxidation, experiments were undertaken to determine the effect of hydrocortisone on several parameters of human PMN function. The phagocytic and bactericidal capacity of PMN with or without hydrocortisone (2.1 mM) was determined by quantitation of cell-free, cell-associated, and total bacteria. Phagocytosis of Staphylococcus aureus and several gram-negative rods was unimpaired by the presence of hydrocortisone in the media. In contrast, killing of bacteria was markedly impaired by hydrocortisone. After 30 min of incubation, there were 20-400 times as many bacteria surviving in hydrocortisone-treated PMN as in simultaneously run controls without hydrocortisone. The defect of intracellular killing noted in the presence of hydrocortisone was not related to impaired degranulation. Quantitative kinetic studies of degranulation revealed no difference in the release of granule associated acid phosphatase in hydrocortisone-treated and control PMN after phagocytosis. Electron microscopy of PMN also indicated that the presence of hydrocortisone had no effect on the extent of degranulation after phagocytosis. These observations were confirmed by studies using histochemical techniques to detect lysosomal enzymes. After phagocytosis, hydrocortisone-treated PMN demonstrated less NADH oxidase activity, oxygen consumption, and hydrogen peroxide production than postphagocytic control PMN. In addition, Nitro blue tetrazolium dye reduction was diminished in hydrocortisone-treated PMN.Thus, impairment of NADH oxidase activity in normal human PMN by hydrocortisone results in reduced intracellular killing of bacteria, diminished postphagocytic oxygen consumption, decreased ability to reduce Nitro blue tetrazolium, and decreased hydrogen peroxide production. These abnormalities are similar to those seen in the PMN of patients with chronic granulomatous disease of childhood.
Publication
Journal: Journal of Experimental Medicine
April/1/1973
Abstract
Outer thymic cortical large lymphocytes were labeled by transcapsular administration of tritiated thymidine. By 2-4 days after labeling, small and medium labeled lymphocyte descendants were found throughout the cortex and in the medulla. The labeled cortical lymphocytes undergo pycnosis after parenteral administration of hydrocortisone 24 h previously, but their (labeled) medullary descendants do not. In addition, parenteral administration of hydrocortisone at the time of surface labeling results in the absence of the appearance of labeled medullary descendants.
Publication
Journal: Proceedings of the National Academy of Sciences of the United States of America
September/24/1981
Abstract
Fifteen tumor-containing specimens were obtained directly from patients with small cell carcinoma of the lung and tested for their ability to grow in serum-supplemented medium and in serum-free medium supplemented with hydrocortisone, insulin, transferrin, estrogen, and selenium (HITES). The tumor cells replicated in 14 of 15 cases (93%) in the HITES medium and in 10 of 15 cases (67%) in the serum-supplemented medium. The neoplastic origin of the cells growing in the HITES medium was confirmed by standard cytologic criteria, by DNA content analysis using flow cytometry, and by their ability to form colonies in agarose and tumors in athymic nude mice. While the tumor cells had very similar morphologies in both media, the serum-free medium did not support the growth of nonmalignant stromal cells, and essentially pure cultures of replicating tumor cells were obtained 7-10 days after plating. The selectivity of the HITES medium was demonstrated by the failure of cells to grow in 20 specimens cytologically negative for small cell carcinoma and in 9 of 10 specimens containing other tumor types (including other types of lung cancer). The results demonstrate that a chemically defined medium, determined by work on tissue culture-adapted human tumor lines, can support the selective growth of tumor specimens obtained directly from patients. Such selective formulas are probably specific for different tumor types and thus could be used for diagnosis, drug sensitivity testing in vitro, and identification of factors regulating tumor growth. All of these have direct application to patient treatment.
Publication
Journal: Gut
October/31/1998
Abstract
Two consecutive trials of out-patient treatment for mild cases of active ulcerative colitis are described. In the first trial oral prednisone gave significantly better results than a placebo. In the second trial "salazopyrin" gave final results approaching those of prednisone, although over a longer time and with a higher incidence of unpleasant side-effects, but topical hydrocortisone gave disappointing results, probably because the technique of administration was not suitable for ordinary out-patient use.
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