Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027947 (neutropenia)
 17,527 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Polymorphonuclear neutrophils (PMNs) may contribute to organ injury in both hemorrhagic and endotoxic shock. Both models of shock exhibit a "flight of the leukocytes," but the mechanisms for entrapment of leukocytes in the microcirculation differ. The objective of this study was to investigate lipopolysaccharide (LPS)-induced shock and hemorrhagic shock with similar survival rates, in terms of circulating PMNs, activated circulating PMNs, plasma tumor necrosis factor (TNF) activity, and PMN adhesion. In the LPS protocol, rats received 6.5 mg/kg E. coli LPS i.v., which resulted in 50% survival. In the hemorrhagic shock protocol, rats were maintained for 3 h at 40 mm Hg mean arterial pressure, and survival during a 24-h observation period was 40%. LPS injection and hemorrhage caused rapid neutropenia in survivors and nonsurvivors. Low circulating PMN counts persisted during hypotension in the hemorrhagic protocol and among nonsurvivors in the LPS protocol, but in both protocols a tendency toward significantly higher circulating PMN counts in survivors compared with nonsurvivors was found. In both protocols, survivors had significantly lower fractions of circulating activated PMNs and lower adhesion of circulating PMNs to nylon fibers. In the LPS protocol, higher plasma TNF activity was found in nonsurvivors than in survivors, but no TNF activity in plasma could be found throughout the hemorrhagic protocol. These results indicate that nonsurvivors in both shock models exhibit higher levels of PMN activation. No correlation was detected between PMN activation and plasma TNF activity to suggest that TNF serves as the primary mediator of circulating PMN activation.
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PMID:Neutrophil activation, tumor necrosis factor, and survival after endotoxic and hemorrhagic shock. 869 57

B464 is a novel synthetic analog of lipid A, a toxic component of endotoxin (LPS; lipopolysaccharide). We investigated the effects of B464 on both LPS-induced cellular responses in vitro and acute lung injury in vivo. In the in vitro study, B464 inhibited tumor necrosis factor-alpha (TNF-alpha) production from human monocytes, priming and stiffening of neutrophils, and expression of adhesion molecules on endothelial cells induced by LPS. We then studied the effects of B464 pretreatment on acute lung injury elicited by intravenous LPS administration in vivo. Guinea pigs were divided into saline control, B464 alone, LPS alone, and LPS + B464 groups. Animals were observed for 4 h after LPS administration, and lung injury was evaluated by extravascular lung water, 125I-albumin leakage in lung tissue, and lung neutrophil accumulation. In the LPS alone group, rapid and sustained peripheral neutropenia (p < 0.001 versus saline at 15 min and at 1, 2, and 4 h), an increased plasma TNF-alpha concentration (p < 0.005 at 1 h), and increases in lung injury parameters (p < 0.05) were observed. In the LPS + B464 group, no changes were observed in either plasma TNF-alpha or lung injury parameters. Transient peripheral neutropenia and subsequent rapid recovery (p > 0.05, p < 0.001, p < 0.01, and p > 0.05 at 15 min and 1, 2, and 4 h, respectively) were observed in the LPS + B464 group. These in vivo data, together with in vitro evidence of suppressed cellular responses, suggest that B464 (1) inhibits neutrophil accumulation in lung tissue, and (2) attenuates the development of acute lung injury by blocking the activation of neutrophils and mononuclear cells as well as the interaction between neutrophils and endothelial cells.
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PMID:Protective effect of B464, a lipid A analog, on endotoxin-induced cellular responses and acute lung injury. 888 83

The pathogenesis of alpha-hemolytic streptococcus shock syndrome (SS), a life-threatening complication in neutropenic patients following aggressive chemotherapy that is caused by viridans streptococci, is unknown. We measured serum concentrations of proinflammatory and antiinflammatory cytokines and T cell activation markers in two patients with lethal alpha-hemolytic streptococcus SS. The results were compared with those for controls, two neutropenic patients with uncomplicated bacteremia due to gram-positive organisms and four patients with neutropenia and bacteremia due to gram-negative organisms (two of whom had lethal septic shock). In patients with alpha-hemolytic streptococcus SS, levels of interleukin (IL) 1 were undetectable, levels of tumor necrosis factor (TNF) alpha were only slightly elevated, and IL-6 was the only proinflammatory cytokine that was found in high concentrations and had a late peak level at the time of clinical deterioration. IL-6 levels were much higher in patients with alpha-hemolytic streptococcus SS than in controls with uncomplicated bacteremia due to gram-positive organisms but were comparable with those in controls with bacteremia due to gram-negative organisms. Soluble TNF receptor fragments and IL-1 receptor antagonist apparently were not protective despite high serum concentrations.
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PMID:Levels of cytokines and cytokine inhibitors in the neutropenic patient with alpha-hemolytic streptococcus shock syndrome. 890 45

The term myelodysplasia (MDS) refers to a group of bone marrow failure syndromes which are relatively rare in childhood. The pathogenesis of MDS is unknown, but a variety of chromosomal, molecular, and cytochemical abnormalities have been reported. We describe a 4-month-old female with MDS who presented with severe neutropenia and refractory anemia with excess blasts (RAEB). Bone marrow progenitor cell assays showed decreased erythroid and myeloid colony formation as compared to normal marrow, and the patient's serum further diminished colony formation of both her own and control marrow. These observations suggested the presence of a soluble factor inhibitory to hematopoiesis. Reverse transcriptase-polymerase chain reaction (RT-PCR) analysis of total RNA derived from the patient's bone marrow mononuclear cells revealed highly elevated tumor necrosis factor-alpha (TNF-alpha) mRNA levels. Using a similar RT-PCR profile, TNF-alpha mRNA levels were found to be elevated in two other children with myelodysplasia. We conclude that TNF-alpha is produced in large amounts by bone marrow mononuclear cells of children with MDS, and we hypothesize that TNF-alpha plays an important role in the pathophysiology of the ineffective hematopoiesis observed in MDS.
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PMID:Tumor necrosis factor-alpha suppresses hematopoiesis in children with myelodysplasia. 895 Mar 41

Human CD34+ multilineage progenitor cells (CD34HPC) from cord blood and bone marrow express CD40, a member of the tumor necrosis factor-receptor family present on various hematopoietic and nonhematopoietic cells. As hyper-IgM patients with mutated CD40 ligand (CD40L) exhibit neutropenia, no B cell memory, and altered T cell functions leading to severe infections, we investigated the potential role of CD40 on CD34HPC development. CD40-activated cord blood CD34HPC were found to proliferate and differentiate independently of granulocyte/macrophage colony-stimulating factor, into a cell population with prominent dendritic cell (DC) attributes including priming of allogeneic naive T cells. DC generated via the CD40 pathway displayed strong major histocompatibility complex class II DR but lacked detectable CD1a and CD40 expression. These features were shared by a dendritic population identified in situ in tonsillar T cell areas. Taken together, the present data demonstrate that CD40 is functional on CD34HPC and its cross-linking by CD40L+ cells results in the generation of DC that may prime immune reactions during antigen-driven responses to pathogenic invasion, thus providing a link between hematopoiesis, innate, and adaptive immunity.
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PMID:CD40 ligation on human cord blood CD34+ hematopoietic progenitors induces their proliferation and differentiation into functional dendritic cells. 901 82

The effects of lisofylline [(R)-1-(5-hydroxyhexyl)-3,7-dimethylxanthine] (LSF), an inhibitor of de novo phosphatidic acid (PA) generation, on sepsis-induced acute lung injury was studied using Hanford minipigs weighing 18 to 25 kg. Sepsis was induced by an intravenous infusion of Pseudomonas aeruginosa (1 x 10(6)/colony-forming units/kg/min over 2 h). Saline was used as the control vehicle. Six groups were studied: saline control group (SALINE: n = 5); sepsis control group (SEPSIS: n = 5); LSF control group (LSF: n = 5), which received a 25-mg/kgbolus of LSF 30 min before time zero followed by continuous infusion of 10 mg/kg/h throughout the study; LSF-treated septic groups, which were treated with LSF 30 min prior to sepsis (Pre: n = 5), 1 h postonset (Post-1 h: n = 8) or h postonset (Post-2 h: n = 8) of the bacterial infusion. Hemodynamics PaO2, neutrophil counts, and plasma porcine tumor necrosis factor-alpha concentrations were monitored for 6 h. After the minipigs were killed, lung tissue was sampled to measured wet-to-dry weight ratio (W/D), tissue albumin index (TAI), thiobarbituric acid-reactive material content (TBARM), and myeloperoxidase (MPO) activity. Compared with the SALINE group, the SEPSIS group showed significant systemic hypotension, pulmonary hypertension, arterial hypoxemia, neutropenia, and increase in TNF-alpha, MPO activity, W/D, TBARM, and TAI. LSF treatment attenuated sepsis-induced pulmonary hypertension, neutropenia, and hypoxemia, and increased MPO activity and lung injury measurements in the Pre and Post-1 h groups, but its efficacy was blunted in the Post-2 h group. Plasma TNF-alpha was decreased only in the Pre group. Thus, inhibition of intracellular PA generation through de novo pathways attenuates sepsis-induced acute lung injury.
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PMID:The effects of post-treatment with lisofylline, a phosphatidic acid generation inhibitor, on sepsis-induced acute lung injury in pigs. 911 28

The aim of the study was to investigate the effects of high-dose medroxyprogesterone acetate (MPA) on the tumor necrosis factor-alpha (TNF-alpha) release in patients with chemotherapy-induced neutropenia. We also evaluated the effects of high-dose MPA on hematological parameters (leukocyte, neutrophil, platelet, hemoglobin, hematocrit) and side effects of MPA. One week following the first cycle chemotherapy, 20 patients who developed neutropenia were enrolled in the study. One gram/day MPA was administered orally to the patients and was continued from one week following the first chemotherapy cycle to one week after the second chemotherapy cycle. The patients received the second chemotherapy cycle at the same dosages as the first cycle. Before MPA treatment TNF-alpha levels were lower than post-treatment levels, but the difference was not statistically significant (P > 0.05). The differences in the mean leukocyte and neutrophil counts before and after the high-dose MPA treatment were statistically significant (p < 0.05).
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PMID:Effect of high-dose medroxyprogesterone acetate on tumor necrosis factor-alpha release in patients with chemotherapy-induced neutropenia. 937 94

A Phase II trial using interleukin 1alpha (IL-1alpha) and etoposide for patients with relapsed osteosarcoma (OS) was undertaken to assess the feasibility and tolerability of combination therapy with biotherapy and chemotherapy. Nine patients with histologically proven relapsed OS were treated with IL-1alpha immediately followed by etoposide daily for 5 days every 3 weeks. Surgical resection of lung metastasis or peripheral tumor was performed after two or three cycles. We observed three partial responses; disease was stable in another case. One case could not be evaluated. The side effects associated with combination therapy were as predicted from known side effects of the individual agents; however, more profound neutropenia was observed. Four patients exhibited clinical signs of capillary leak syndrome, i.e., hypotension, edema, and weight gain. The etiology of the capillary leak was unclear, because serum IL-1alpha, IL-2, tumor necrosis factor, and nitric oxide levels could not be used to predict which patients would develop capillary leak. Histological analysis of tumor specimens obtained after two or more courses of therapy showed changes consistent with a response to a biological response modifier: peripheral fibrosis surrounded the metastasis with infiltration of chronic and acute inflammatory cells. Because the response of relapsed OS to any type of salvage regimen has been poor, we interpret the clinical response of this therapy as good. However, the significant side effects associated with this therapy must also be taken into consideration before deciding to use this combination therapy. It is unfortunate that the study was stopped early due to halted production of IL-1alpha. If this agent is again manufactured for clinical use, we conclude that additional evaluation in patients with relapsed OS is warranted.
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PMID:Phase II study of recombinant interleukin 1alpha and etoposide in patients with relapsed osteosarcoma. 981 56

Severe weight loss associated with cancer continues to be a major cause of morbidity in cases of childhood malignancy. The etiology is not completely understood but is probably multifactorial, including reduced ingestion and altered metabolism of nutrients. Changes in the host metabolism of protein, fat and carbohydrate in the cancer-bearing host have been demonstrated both in animal models and in patients. Changes include increased protein turnover and loss of the normal compensatory mechanisms seen in starvation. Additionally, increased lipid breakdown results in depletion of lipid stores and changes in carbohydrate metabolism result in an energy-losing cycle. The increase in protein turnover seen in children with leukemia may be related to the tumor, the chemotherapy administered or to related conditions such as febrile neutropenia. The role of endogenous mediators of cancer cachexia has not yet been clearly elucidated, although tumor necrosis factor, interleukin I and interleukin 6 appear to be involved. Studies of energy expenditure in children with cancer have indicated that certain patients with a raised metabolic rate are at particular risk of severe weight loss. The challenge is to identify these vulnerable patients and to provide adequate nutritional support early in treatment and therefore avoid the deleterious effects of cachexia.
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PMID:Aspects of altered metabolism in children with cancer. 987 81

To develop a T-cell-based therapy for carcinomas, the superantigen staphylococcal enterotoxin A (SEA) was supplied with tumor specificity by means of a recombinant fusion of the Fab fragment of the monoclonal antibody C242 recognizing human colorectal (CRC) and pancreatic carcinomas (PC). Using this Fab-SEA fusion protein (PNU-214565), potent cytotoxicity by activation of T cells can be obtained in the targeted area. Twenty-one patients with CRC and 3 with PC were treated with single, escalating doses of PNU-214565 to establish the maximum tolerated dose (MTD) and to define toxicities. The doses ranged from 0.01 ng/kg to 4.0 ng/kg with three patients at each dose level, except for the dose of 1.5 ng/kg with which six patients were treated because of dose-limiting toxicity. Adverse events (AE) were transient: 13 patients experienced mild to moderate fever. In one patient, a grade 3 fever was followed by a grade 2 hypotension. Other mild or moderate AEs were fatigue, nausea, vomiting, diarrhea, and abdominal pain. No significant hematological toxicity occurred. Immune activation was highly variable with strong activity in peripheral blood seen only in two patients at the dosage level 1.5 ng/kg. They showed pronounced elevations of interleukin-2 (IL-2), IL-6, tumor necrosis factor-alpha, and interferon-gamma, 3-5 hours after the start of infusion. In one patient, IL-2 and IL-6 increased substantially (2,925 U/mL and 32,000 U/mL) concomitantly with grade 3 fever and transient grade 2 neutropenia, grade 2 lymphopenia, and grade 2 monocytopenia. In conclusion, a single 3-hour infusion of PNU-214565 could be safely administered up to 4 ng/kg. MTD was not determined. Instead, a repeat-dose trial was initiated starting at 0.5 ng/kg, considered safe in this trial, with the objective of defining the MTD.
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PMID:Phase I study of single, escalating doses of a superantigen-antibody fusion protein (PNU-214565) in patients with advanced colorectal or pancreatic carcinoma. 1068 47


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