Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0036690 (sepsis)
 59,461 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Sepsis induces metabolic disorders that include loss of body weight, muscle wasting, and acute-phase protein synthesis in liver. Cytokines are generally recognized as active mediators of these disorders, and the implication of tumor necrosis factor (TNF) has been frequently discussed in the recent past. However, the identity of the active agent in alterations of protein metabolism is still controversial. To improve our understanding of the role of cytokines in mediating muscle wasting observed in sepsis, we investigated muscle and liver protein metabolism in the following three groups of rats: infected control rats (INF-C); infected rats pretreated with pentoxifylline (PTX-INF), which is a potent inhibitor of TNF secretion; and pair-fed rats for the PTX-INF group pretreated with pentoxifylline. Pentoxifylline nearly completely suppressed TNF secretion but did not influence the transient fall in rectal temperature, the decreased hematocrit, and the increased liver protein mass and synthesis observed in INF-C rats. Pentoxifylline decreased the anorexia, the loss of body weight and muscle protein observed in INF-C animals, and partially prevented the decrease in muscle protein synthesis induced by infection. The overall data indicate that pentoxifylline is an effective agent in mitigating the characteristic muscle protein wasting induced by sepsis and confirm the limited role of TNF in the mediation of the acute-phase protein synthesis. Our results suggest a probable implication of TNF in the regulation of protein balance in muscle but do not allow discarding possible implication of other mediators that would be inhibited by pentoxifylline.
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PMID:Pentoxifylline decreases body weight loss and muscle protein wasting characteristics of sepsis. 823 42

It is widely assumed that infections are the principal cause and primary outcome determinant of the syndrome of Multiple Organ Failure (MOF) in critically ill patients. Infections are frequent in these patients, but the prevention and treatment of infections may not influence the course of MOF. This study tested the hypothesis that infections play a decisive role in the outcome of MOF. Data were gathered concurrently on all adult patients admitted over an 18-month period to a non-cardiac surgical ICU at a university hospital and recorded in a computer database. Sepsis was defined as a state characterized by at least three of the following: fever, tachycardia, leukocytosis or leukopenia, increased cardiac index, reduced systemic vascular resistance, and hypercatabolism manifested by nitrogen-wasting. The presence of an infection was not required for the diagnosis of sepsis. Mild sepsis was defined as the presence of three or four parameters. Severe sepsis was defined as the presence of five or six parameters. MOF was defined as the development of dysfunction of at least two of the following major organ systems: cardiac, gut, pulmonary, renal, cerebral, and hepatic. Of 749 admissions, 73 patients developed MOF. Thirty four (47%) had a documented source of infection, 37 (51%) had positive blood cultures, and all had sepsis. Hospital mortality was 66 percent (48 of 73 patients). Death could not be predicted by bacteremia (P > 0.25), nor by the presence of an infectious source (P = 1.0), but was strongly associated with severe sepsis (P < 0.0005).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:The role of infection in outcome of Multiple Organ Failure. 823 94

Chronic TNF treatment for 8 days resulted in an increased protein turnover in most of the tissues studied. The increased turnover could be observed in both the synthetic and degradation fractional constants; however, in the majority of the tissues (muscle, diaphragm, heart, kidneys, lungs and brown adipose) the increase in Kd was higher than that of Ks resulting thus in a reduced protein accumulation (Ka). In contrast, chronic TNF treatment resulted in an increased brain protein accumulation. The data presented suggest that the cytokine could be involved in tissue wasting in pathological states such as sepsis and malignancy.
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PMID:Chronic tumour necrosis factor-alpha treatment modifies protein turnover in rat tissues. 835 33

We studied the alterations in skeletal muscle protein breakdown in long lasting sepsis using a rat model that reproduces a sustained and reversible catabolic state, as observed in humans. Rats were injected intravenously with live Escherichia coli; control rats were pair-fed to the intake of infected rats. Rats were studied in an acute septic phase (day 2 postinfection), in a chronic septic phase (day 6), and in a late septic phase (day 10). The importance of the lysosomal, Ca2+ -dependent, and ubiquitin-proteasome proteolytic processes was investigated using proteolytic inhibitors in incubated epitrochlearis muscles and by measuring mRNA levels for critical components of these pathways. Protein breakdown was elevated during the acute and chronic septic phases (when significant muscle wasting occurred) and returned to control values in the late septic phase (when wasting was stopped). A nonlysosomal and Ca2+ -independent process accounted for the enhanced proteolysis, and only mRNA levels for ubiquitin and subunits of the 20 S proteasome, the proteolytic core of the 26 S proteasome that degrades ubiquitin conjugates, paralleled the increased and decreased rates of proteolysis throughout. However, increased mRNA levels for the 14-kD ubiquitin conjugating enzyme E2, involved in substrate ubiquitylation, and for cathepsin B and m-calpain were observed in chronic sepsis. These data clearly support a major role for the ubiquitin-proteasome dependent proteolytic process during sepsis but also suggest that the activation of lysosomal and Ca2+ -dependent proteolysis may be important in the chronic phase.
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PMID:Muscle wasting in a rat model of long-lasting sepsis results from the activation of lysosomal, Ca2+ -activated, and ubiquitin-proteasome proteolytic pathways. 860 25

Tissue factor, a member of the cytokine-receptor superfamily and high-affinity receptor and cofactor for plasma factor VII/VIIa (ref. 1), is the primary cellular initiator of blood coagulation. It is involved in thrombosis and inflammation associated with sepsis, atherosclerosis and cancer, and can participate in other cellular processes including intracellular signalling, metastasis, tumor-associated angiogenesis, and embryogenesis. Here we report that inactivation of the tissue factor gene (TF) results in abnormal circulation from yolk sac to embryo beyond embryonic day 8.5, leading to embryo wasting and death. Vitelline vessels from null mice were deficient in smooth-muscle alpha-actin-expressing mesenchymal cells, which participate in organization of the vessel wall. This implies that tissue factor has a role in blood vessel development.
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PMID:Role of tissue factor in embryonic blood vessel development. 877 17

Fluid exchange disorders due to capillary lesions are numerous and their extent depends on the underlying disease as well as the capillary structure of the affected organ. The inflammatory cascade, triggered by sepsis or reperfusion injury, is mediated by several humoral mediators and activated blood cells. These include pro-inflammatory cytokines, arachidonic acid, proteases, oxygen free radicals, polymorphonuclears, procoagulant, complement and fibrinolytic system. The interaction between these mediators leads to a loss of endothelial integrity, a loss of basment membrane and a disruption of the interstitial matrix, with wasting of the endothelial cytoskeleton. The alteration in permeability induces transcapillary exudation of water and protein in the interstitial space, leading to organ dysfunction, mainly the lungs and splanchnic organs. Nitric oxyde, by modulating the response of the endothelium to the cellular interaction may protect against capillary injury. Capillary "stress lesions" following microvascular hypertension are the physiological basis of neurogenic or high altitude pulmonary oedema, and overinflation injury from mechanical ventilation. The anatomic specific features of the cerebral capillaries resulted in the well known concept of blood brain barrier with it's changeing morphology. Under the effect of humoral mediators and cellular interactions, the endothelial cells are able, via a calcium-mediated mechanism, to contract and to modify capillary permeability, leading to vasogenic oedema.
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PMID:[Transvascular fluid exchange disturbed by capillary injuries]. 888 82

Skeletal muscle protein wasting is a prominent feature of the metabolic response to sepsis. Persistent protein wasting leads to muscle dysfunction and prolongs recovery from the septic insult. Unfortunately, conventional nutritional support alone does not prevent the sepsis-induced weight loss and catabolism of muscle. Hence, mechanisms other than substrate deficiency appear to be involved in the derangements in protein metabolism during sepsis. The catabolism of muscle during sepsis results from a stimulation of proteolysis and an inhibition of protein synthesis. This review summarizes the mechanisms responsible for alterations in protein synthesis and degradation in muscle during sepsis at the biochemical level. The ability of hormones (insulin, insulin-like growth factor I, glucocorticoids) or cytokines (tumor necrosis factor, interleukin-1) to act as mediators of protein catabolism is also examined. Finally, we discuss the potential role of anticytokine therapies in preventing derangements in protein metabolism during sepsis. A picture is emerging which suggests that cytokines may influence skeletal muscle protein metabolism during sepsis both indirectly through inhibition of the regulatory actions of anabolic hormones on protein turnover, and directly through modulation of the protein synthesis and degradation enzymatic machinery.
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PMID:Regulation of skeletal muscle protein turnover during sepsis: mechanisms and mediators. 898 31

The production of pro-inflammatory cytokines, such as interleukins 1 and 6 and tumour necrosis factors, occurs rapidly following trauma or invasion of the body by pathogenic organisms. The cytokines mediate the wide range of symptoms associated with trauma and infection, such as fever, anorexia, tissue wasting, acute phase protein production and immunomodulation. In part, the symptoms result from a co-ordinated response, in which the immune system is activated and nutrients released, from endogenous sources, to provide substrate for the immune system. Although the cytokine mediated response is an essential part of the response to trauma and infection, excessive production of pro-inflammatory cytokines, or production of cytokines in the wrong biological context, are associated with mortality and pathology in a wide range of diseases, such as malaria, sepsis, rheumatoid arthritis, inflammatory bowel disease, cancer and AIDS. Cytokine biology can be modulated by antiinflammatory drugs, recombinant cytokine receptor antagonists and nutrients. Among the nutrients, fats have a large potential for modulating cytokine biology. A number of trials have demonstrated the anti-inflammatory effects of fish oils, which are rich in n-3 polyunsaturated fatty acids, in rheumatoid arthritis, inflammatory bowel disease, psoriasis and asthma. Animal studies, conducted by ourselves and others, indicate that a range of fats can modulate pro-inflammatory cytokine production and actions. In summary fats rich in n-6 polyunsaturated fatty acids enhance IL1 production and tissue responsiveness to cytokines, fats rich in n-3 polyunsaturated fatty acids have the opposite effect, monounsaturated fatty acids decrease tissue responsiveness to cytokines and IL6 production is enhanced by total unsaturated fatty acid intake. There are a large number of potential cellular mechanisms which may mediate the effects observed. The majority relate to the ability of fats to alter the composition of membrane phospholipids. As a consequence of alterations in phospholipid composition, membrane fluidity may change, altering binding of cytokines to receptors and G protein activity. The nature of substrate for various signalling pathways associated with cytokine production and actions may also be changed. Consequently, alterations in eicosanoid production and activation of protein kinase C may occur. We have examined a number of these potential mechanisms in peritoneal macrophages of rats fed fats with a wide range of fatty acid composition. We have found that the total C18:2 and 20:4 diacyl species of phosphatidylethanolamine in peritoneal macrophages relates in a positive curvilinear fashion with dietary linoleic acid intake; that TNF induced IL1 and IL6 production relate in a positive curvilinear fashion to linoleic acid intake; that leukotriene B4 production relates positively with dietary linoleic acid intake over a range of moderate intakes and is suppressed at high intakes, while PGE2 production is enhanced. There was no clear relationship between linoleic acid intake and membrane fluidity, however fluidity was influenced in a complex manner by the type of fat in the diet, the period over which the fat was fed and the presence of absence of TNF stimulation. None of the proposed mechanisms, acting alone, can explain the positive effect of dietary linoleic acid intake on pro-inflammatory cytokine production. However each may be involved, in part, in the modulatory effects observed.
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PMID:Modulation of pro-inflammatory cytokine biology by unsaturated fatty acids. 955 30

Mother-to-child rates of HIV transmission are high in Africa. Findings are presented on 62 HIV-positive infants admitted to the Missionaries of Charity Orphanage, Addis Ababa, who were followed from July 25, 1991, to July 30, 1995. The infants were provided with regular clinical examination and treatment by a physician, as well as the monitoring of their HIV serostatus every 3 months until age 18 months and every year thereafter. Among infants over age 18 months, 14 were HIV seropositive and alive, and 4 were HIV positive, but died. 11 children were HIV positive and died before age 18 months and 33 seroreverted to HIV seronegative status. The level of mother-to-child HIV transmission was 29-47%. Among the clinical signs presented, generalized lymphadenopathy, hepatomegaly, splenomegaly, wasting, stunting, and delayed motor development were more often found in the definitely HIV-positive children. Upper respiratory tract infections, acute diarrhea, pneumonia, pyogenic skin infections, sepsis, and candidal infections were the most commonly seen illnesses.
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PMID:A four-year cohort study of HIV seropositive Ethiopian infants and children: clinical course and disease patterns. 957 11

Prophylactic hemodialysis has been employed in the treatment of 15 patients with acute renal failure due to acute tubular necrosis (12), bilateral renal cortical necrosis (two), and poststreptococcal glomerulonephritis (one). Dialyses, usually lasting six hours each, were begun before clinical evidence of uremia developed in each patient and/or before the nonprotein nitrogen reached 200 mg.%, and were repeated daily or often enough to maintain the nonprotein nitrogen below 150 mg.%. The hypothesis underlying this technic postulates (1) that wasting, sepsis and impaired wound healing in these patients may reflect tissue injury by the same dialyzable toxic agents which produce the uremic symptoms that are readily reversible by dialysis, and (2) that repeated dialyses should therefore prevent both clinical uremia and the later, often lethal sequelae. The results contrast dramatically with our own past experience in treating patients with acute renal failure with a carefully executed medical regimen together with hemodialysis on conventional indications. Except in one instance of crush injury with progressive intracerebral damage, and one brief occasion in another individual, these patients experienced a stable, convalescent clinical course, remained free of uremic symptoms or chemical imbalances, ate at least three meals daily which were unrestricted in amount and composition, and were ambulatory between dialyses unless confined to bed by associated disease. Wounds healed well. Infection either did not occur, or subsided after appropriate therapy. Fluid restriction was liberalized by means of ultrafiltration with dialysis. Regional heparinization of only the extracorporeal circuit eliminated actual or impending bleeding as a contraindication to dialysis. Chronic vessel cannulation made the frequent dialyses possible, but may have provided the route for repeated, transient bacterial contamination of the blood stream in the first hour of many dialyses. Marked anemia, despite reticulocytosis, moderate to mild weight loss and some mental deficit persisted in spite of the general clinical improvement and well-being. Three patients with tubular necrosis died after seven, 11 and 26 days of oliguria; both patients with bilateral renal cortical necrosis also succumbed, on the seventy-third and ninety-second days of renal failure, and after 29 and 40 dialyses, respectively. At autopsy, evidence of sepsis was conspicuously absent. The remaining 10 patients survived. Thus some, but not all, clinical manifestations of acute renal failure appear to be favorably influenced by prophylactic dialysis treatment. Our initial experience in this group of 15 patients does not of course prove that freedom from complications and a significantly better outlook for survival can be assured to patients with acute renal failure by these methods. However, it seems to offer a reasonable hope of this possibility which we cannot attach to management by medical measures alone, or by dialysis on conventional indications. If this hope is realized in greatly extended, subsequent series, then it seems inevitable that some form of prophylactic dialysis, or some equally effective alternative, should be adopted in treating the majority of patients with acute renal failure.
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PMID:Prophylactic hemodialysis in the treatment of acute renal failure. Annals of Internal Medicine, 53:992-1016, 1960. 984 96


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