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Bernard BK, Harris JE, Fischer JE. An evaluation of the safety of Crodamol PMP. FOOD ADDITIVES AND CONTAMINANTS 1998; 15:427-36. [PMID: 9764213 DOI: 10.1080/02652039809374663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Crodamol PMP (polyoxypropylene (2) myristyl ether propionate) has been extensively employed for many years in a wide variety of human cosmetics in the absence of reported adverse reactions. The compound is being considered for use as a vehicle for veterinary pharmaceuticals in food-producing animals. This paper reviews information on the chemistry, metabolism, and toxicity of this compound, including the details of a recently completed multi-dose study in rats. Based upon this information, it is concluded that Crodamol PMP is a substance of apparently low toxic potential. Potential new uses of this compound must compare the likely exposure to the substance with the available toxicity information.
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Fang CH, Li BG, James JH, Fischer JE, Hasselgren PO. The anabolic effects of IGF-1 in skeletal muscle after burn injury are not caused by increased cell volume. JPEN J Parenter Enteral Nutr 1998; 22:115-9. [PMID: 9586787 DOI: 10.1177/0148607198022003115] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND In a recent report, insulin-like growth factor 1 (IGF-1) stimulated protein synthesis and inhibited protein breakdown in skeletal muscle after bum injury. The mechanism of the anabolic effects of IGF-1 in skeletal muscle is not known. We tested the hypotheses that IGF-1 stimulates protein synthesis and inhibits protein breakdown in skeletal muscle secondary to cell swelling and that cell swelling in itself induces an anabolic response in muscle tissue. METHODS Extensor digitorum longus muscles from control and burned rats were incubated in the absence or presence of 1 microg/mL of IGF-1. Protein synthesis and breakdown rates were determined by measuring incorporation of 14C-phenylalanine into protein and net release of tyrosine, respectively. Cell volume was measured by determining wet and dry weight and by using 3H-mannitol as an extracellular marker. RESULTS IGF-1 stimulated protein synthesis and inhibited protein breakdown in muscles from nonburned and burned rats without influencing cell volume. Incubating muscles in hypo-osmotic medium increased cell volume by 17% and inhibited protein breakdown by 14% but did not influence protein synthesis. CONCLUSIONS The anabolic effects of IGF-1 in skeletal muscle are not caused by increased cell volume. The results differ from those reported previously in liver cells in which the anabolic effects of IGF-1 were associated with cell swelling. The role of changes in cell volume in the regulation of protein metabolism may be different in skeletal muscle than in other tissues.
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Wang Q, Wang JJ, Boyce S, Fischer JE, Hasselgren PO. Endotoxemia and IL-1 beta stimulate mucosal IL-6 production in different parts of the gastrointestinal tract. J Surg Res 1998; 76:27-31. [PMID: 9695734 DOI: 10.1006/jsre.1998.5288] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
BACKGROUND In recent studies, sepsis and endotoxemia were associated with increased IL-6 production in mucosa of the jejunum. We tested the hypothesis that endotoxemia in mice stimulates mucosal IL-6 production in other parts of the gastrointestinal tract as well and that the enterocyte is a source of mucosal IL-6. In addition, we examined the effects of TNF alpha and IL-1 beta on mucosal IL-6 production. MATERIALS AND METHODS Endotoxin (12.5 mg/kg) was injected subcutaneously in mice. Control mice were injected with a corresponding volume of sterile saline. After 4 h, IL-6 levels were determined in mucosa of stomach, jejunum, ileum, and colon and in plasma and liver. In a second series of experiments, immunohistochemistry was performed of jejunal mucosa to determine in which cell type IL-6 was expressed. Finally, 100 micrograms/kg of human recombinant TNF alpha or human recombinant IL-1 beta was injected intraperitoneally in mice and IL-6 levels were determined in plasma and tissues after 4 h. RESULTS Endotoxemia resulted in increased mucosal IL-6 levels in small and large bowel but in reduced IL-6 levels in gastric mucosa. Immunohistochemistry of jejunal mucosa showed that IL-6 was expressed mainly in the enterocyte and in a few cells of the lamina propria. Treatment of mice with TNF alpha reduced IL-6 levels in gastric mucosa whereas IL-1 beta increased IL-6 levels in mucosa of small intestine. CONCLUSION Mucosal IL-6 production during endotoxemia is differentially regulated along the gastrointestinal tract. Both TNF alpha and IL-1 beta may be involved in the regulation of gastrointestinal IL-6 production during endotoxemia.
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Fischer JE, Janousek M, Fischer M, Seifarth FG, Blau N, Fanconi S. Effect of collection and preprocessing methods on neutrophil elastase plasma concentrations. Clin Biochem 1998; 31:131-6. [PMID: 9629485 DOI: 10.1016/s0009-9120(98)00008-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVES Elevated plasma levels of the elastase alpha 1-proteinase inhibitor complex (E-alpha 1 PI) have been proposed as a marker of bacterial infection and neutrophil activation. Liberation of elastase from neutrophils after collection of blood may cause falsely elevated results. Collection methods have not been validated for critically ill neonates and children. We evaluated the influence of preanalytical methods on E-alpha 1 PI results including the recommended collection into EDTA tubes. DESIGN AND METHODS First, we compared varying acceleration speeds and centrifugation times. Centrifugation at 1550 g for 3 min resulted in reliable preparation of leukocyte free plasma. Second, we evaluated all collection tubes under consideration for absorption of E-alpha 1 PI. Finally, 12 sets of samples from healthy adults and 42 sets obtained from critically ill neonates and children were distributed into the various sampling tubes. Samples were centrifuged within 15 min of collection and analyzed with a new turbidimetric assay adapted to routine laboratory analyzers. RESULTS One of the two tubes containing a plasma-cell separation gel absorbed 22.1% of the E-alpha 1 PI content. In the remaining tubes without absorption of E-alpha 1 PI no differences were observed for samples from healthy adult patients. However, in samples from critically ill neonates or children, significantly higher results were obtained for plain Li-heparin tubes (mean = 183 micrograms/L), EDTA tubes (mean = 93 micrograms/L), and citrate tubes (mean = 88.5 micrograms/L) than for the Li-hep tube with cell-plasma separation gel and no absorption of E-alpha 1 PI (mean = 62.4 micrograms/L, p < 0.01). CONCLUSION Contrary to healthy adults, E-alpha 1 PI results in plasma samples from critically ill neonates and children depend on the type of collection tube.
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Fischer JE, Fanconi S. Percutaneous central venous catheterization in premature infants: a method for facilitating insertion of silastic catheters via peripheral veins. Pediatrics 1998; 101:477-9. [PMID: 9481018 DOI: 10.1542/peds.101.3.477] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Peripheral venous cannulation is the preferred method of inserting central venous silastic catheters in premature infants. The standard techniques are placement of the catheter using a breakaway introducer needle or introduction of the catheter through a cannula. In extremely low birth weight infants (<1000 g) successful cannulation is impeded by the small size of the vessels. After repeated attempts, both procedures can be time-consuming and stressful to the infant. We present a modified insertion technique of the standard 2-French silastic catheter with an increased success rate, thus reducing insertion time, stress to the infant, and costs. The method uses the tip of a 20-gauge cannula as dilator/introducer for the 2-French catheter. This tip is inserted into the vessel with a standard 24-gauge cannula. After successful insertion of the dilator/introducer cannula, the standard 2-French catheter can then be advanced easily.
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Fischer JE, Oshel RE. The National Practitioner Data Bank. What you need to know. BULLETIN OF THE AMERICAN COLLEGE OF SURGEONS 1998; 83:24-6. [PMID: 10176802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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Hasselgren PO, Fischer JE. Sepsis: stimulation of energy-dependent protein breakdown resulting in protein loss in skeletal muscle. World J Surg 1998; 22:203-8. [PMID: 9451937 DOI: 10.1007/s002689900370] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Muscle catabolism is a characteristic metabolic response to sepsis, severe infection, and injury. In patients with severe and protracted sepsis, the catabolic response results in muscle wasting and fatigue, which may adversely affect the outcome in these patients. An understanding of the regulation of muscle protein breakdown during sepsis and the mechanisms involved is important from a clinical standpoint and is essential for the development of new therapeutic modalities to prevent protein loss from muscle tissue. Studies in septic patients and experimental animals have provided evidence that the myofibrillar proteins actin and myosin are particularly sensitive to the effects of sepsis. Among the factors that regulate muscle protein breakdown during sepsis, the proinflammatory cytokines tumor necrosis factor and interleukin-1, together with glucocorticoids, are the principal mediators. Intracellular protein breakdown is regulated by multiple proteolytic pathways. Among these, the energy-ubiquitin-dependent pathway accounts for a major portion of muscle protein breakdown during sepsis. The development of specific proteasome inhibitors may make it possible in the future to target the molecular mechanisms of sepsis-induced increase in muscle proteolysis. Such treatment may prove an important avenue to reduce the metabolic cost in patients with severe infection or sepsis.
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Hobler SC, Williams AB, Fischer JE, Hasselgren PO. IGF-I stimulates protein synthesis but does not inhibit protein breakdown in muscle from septic rats. THE AMERICAN JOURNAL OF PHYSIOLOGY 1998; 274:R571-6. [PMID: 9486320 DOI: 10.1152/ajpregu.1998.274.2.r571] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Sepsis is associated with reduced protein synthesis and increased protein degradation in skeletal muscle. We examined the effects of insulin-like growth factor I (IGF-I) on protein synthesis and breakdown in muscles from nonseptic and septic rats. Sepsis was induced by cecal ligation and puncture; control rats were sham operated. Extensor digitorum longus muscles were incubated in the absence or presence of IGF-I at concentrations ranging from 100 ng/ml to 10 micrograms/ml. Total and myofibrillar protein breakdown rates were measured as net release of tyrosine and 3-methylhistidine, respectively. Protein synthesis was determined by measuring incorporation of [U-14C]phenylalanine into protein. IGF-I stimulated protein synthesis in a dose-dependent fashion in muscles from both sham-operated and septic rats, with a maximal effect seen at a hormone concentration between 500 and 1,000 ng/ml. IGF-I inhibited total and myofibrillar protein breakdown in muscles from sham-operated rats, whereas in muscles from septic rats, IGF-I had no effect on protein breakdown, even at high concentrations. The results suggest that protein breakdown in skeletal muscle becomes resistant to IGF-I during sepsis and that this resistance reflects a postreceptor defect.
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Hobler SC, Tiao G, Fischer JE, Monaco J, Hasselgren PO. Sepsis-induced increase in muscle proteolysis is blocked by specific proteasome inhibitors. THE AMERICAN JOURNAL OF PHYSIOLOGY 1998; 274:R30-7. [PMID: 9458895 DOI: 10.1152/ajpregu.1998.274.1.r30] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Recent studies suggest that sepsis stimulates ubiquitin-dependent protein breakdown in skeletal muscle. The 20S proteasome is the catalytic core of the ubiquitin-dependent proteolytic pathway. We tested the effects in vitro of the proteasome inhibitors N-acetyl-L-leucinyl-L-leucinal-L-norleucinal (LLnL) and lactacystin on protein breakdown in incubated muscles from septic rats. LLnL resulted in a dose- and time-dependent inhibition of protein breakdown in muscles from septic rats. Lactacystin blocked both total and myofibrillar muscle protein breakdown. In addition to inhibiting protein breakdown, LLnL reduced muscle protein synthesis and increased ubiquitin mRNA levels, probably reflecting inhibited proteasome-associated ribonuclease activity. Inhibited muscle protein breakdown caused by LLnL or lactacystin supports the concept that the ubiquitin-proteasome pathway plays a central role in sepsis-induced muscle proteolysis. The results suggest that muscle catabolism during sepsis may be inhibited by targeting specific molecular mechanisms of muscle proteolysis.
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Fang CH, Li BG, Tiao G, Wang JJ, Fischer JE, Hasselgren PO. The molecular regulation of protein breakdown following burn injury is different in fast- and slow-twitch skeletal muscle. Int J Mol Med 1998; 1:163-9. [PMID: 9852215 DOI: 10.3892/ijmm.1.1.163] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
We compared the effect of burn injury on the energy-ubiquitin-dependent proteolytic pathway in the fast-twitch extensor digitorum longus (EDL) and the slow-twitch soleus muscle in rats. Rats were subjected to a 30% total body surface area full-thickness burn or sham procedure. At various time points after injury, total and myofibrillar protein breakdown rates were determined in incubated EDL and soleus muscles. The energy-dependent component of protein break-down was determined by incubating muscles in energy-depleting medium. Messenger RNA levels for ubiquitin and RC3, a 20S proteasome subunit, were measured by Northern blot analysis. Burn injury resulted in an approximately 50% increase in total protein breakdown and a 3-4 fold increase in myofibrillar protein breakdown in EDL muscles, and this response reflected increased energy-dependent protein breakdown. In contrast, protein breakdown rates were not significantly influenced by the burn injury in soleus muscles. Ubiquitin mRNA levels were increased almost 10-fold in EDL and approximately 4.5-fold in soleus muscles following burn injury. Burn injury resulted in a 2-fold increase in RC3 mRNA in EDL with no significant changes noted in soleus muscles. The results suggest that the more pronounced effect of burn injury on protein breakdown in fast-twitch than in slow-twitch muscle may reflect different regulation of proteolysis at the molecular level.
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Moon R, Parikh AA, Szabo C, Fischer JE, Salzman AL, Hasselgren PO. Complement C3 production in human intestinal epithelial cells is regulated by interleukin 1beta and tumor necrosis factor alpha. ARCHIVES OF SURGERY (CHICAGO, ILL. : 1960) 1997; 132:1289-93. [PMID: 9403532 DOI: 10.1001/archsurg.1997.01430360035007] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND Sepsis and endotoxemia are associated with increased mucosal production of complement component C3; the enterocyte may be a source of C3 in these conditions. OBJECTIVE To test the hypothesis that interleukin 1beta (IL-1beta) and tumor necrosis factor alpha (TNF-alpha) regulate the production of C3 in the enterocyte at the transcriptional level and that this regulation is potentiated by interferon gamma (IFN-gamma). METHODS Cultured Caco-2 cells, a human intestinal epithelial cell line, were treated with various concentrations of human recombinant IL-1beta (0.005-1.25 ng/mL) or TNF-alpha (1-1000 U/mL) with or without the addition of IFN-gamma (250 U/mL). C3 levels in the culture medium were measured by enzyme-linked immunosorbent assay and cellular messenger RNA levels by Northern blot analysis. RESULTS Treatment of the Caco-2 cells with IL-1beta or TNF-alpha resulted in a time- and dose-dependent increase in C3 production. The use of IFN-gamma alone did not affect C3 production but potentiated the effect of IL-1beta and TNF-alpha in a synergistic manner. C3 messenger RNA levels were increased following stimulation with either cytokine. CONCLUSIONS C3 production in the enterocyte is regulated by IL-1beta and TNF-alpha at the transcriptional level, and this response is potentiated by IFN-gamma. The results suggest that C3 production in the intestinal mucosa may be regulated locally by cytokines in a paracrine or autocrine manner.
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Fang CH, Li BG, James JH, Fischer JE, Hasselgren PO. Cytokines block the effects of insulin-like growth factor-I (IGF-I) on glucose uptake and lactate production in skeletal muscle but do not influence IGF-I-induced changes in protein turnover. Shock 1997; 8:362-7. [PMID: 9361347 DOI: 10.1097/00024382-199711000-00008] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
There is evidence that proinflammatory cytokines are involved in the regulation of muscle protein breakdown in various catabolic conditions but the mechanisms are not fully understood. Previous studies suggest that cytokines reduce circulating and tissue levels of insulin-like growth factor-I (IGF-I) and may block the anabolic effects of the hormone in certain cell types and tissues. We tested the hypothesis that a mixture of tumor necrosis factor alpha, interleukin-1 alpha, and interferon-gamma block the anabolic effects of IGF-I in skeletal muscle. Muscles from burned or unburned rats were incubated in the absence or presence of 1 microgram/mL of IGF-I with or without the addition of the cytokines. As expected, IGF-I stimulated protein synthesis and inhibited protein breakdown in incubated muscles. The cytokines did not influence protein turnover rates in muscles incubated with or without IGF-I. In additional experiments, the effects of IGF-I on glucose uptake and lactate production were tested. IGF-I increased glucose uptake approximately 2.5-fold and stimulated lactate production approximately 5-fold. These effects of the hormone were significantly inhibited by the cytokine mixture. The results suggest that cytokines do not induce protein catabolism by directly inhibiting the anabolic effects of IGF-I in muscle tissue. The inhibitory effects of the cytokines on IGF-I-stimulated glucose transport and lactate production suggest that the lack of effect of cytokines on protein metabolism was not due to a metabolic unresponsiveness of the incubated muscles to the cytokines.
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113
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Griffen FD, Fischer JE. Practice guidelines and liability implications. EAR, NOSE & THROAT JOURNAL 1997; 76:784-8. [PMID: 9397625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
It should be clear that the authors of this article are not enamored of practice guidelines, thinking them of much more potential harm than good. On the other hand, if practice guidelines are deemed essential, then they must be written with the goal of quality patient care advocacy and with an eye toward the possible damage they may do.
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Fischer JE, Johnson JE, Kuli-Zade RK, Johnson TR, Aung S, Parker RA, Graham BS. Overexpression of interleukin-4 delays virus clearance in mice infected with respiratory syncytial virus. J Virol 1997; 71:8672-7. [PMID: 9343225 PMCID: PMC192331 DOI: 10.1128/jvi.71.11.8672-8677.1997] [Citation(s) in RCA: 89] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Although interleukin-4 (IL-4) expression has been implicated in vaccine-enhanced respiratory syncytial virus (RSV) disease, its role in mediating the immune response to primary RSV infection remains unclear. To assess the effect of IL-4 production on typical RSV infection, transgenic mice which either overexpress or fail to express IL-4 were challenged intranasally with RSV and their responses were compared to those of the parent strains. IL-4-deficient mice eliminated virus from the lung as quickly as did C57BL/6 controls. In contrast, mice which constitutively overexpress IL-4 showed delayed virus clearance compared with mice of the FVB/N control strain, although peak viral titers did not differ. IL-4 overexpression increased the magnitude of the subsequent antibody response. Lung lymphocytes harvested from IL-4-overexpressing mice post-RSV challenge showed diminished RSV-specific cytolytic activity compared with controls. Both IL-4-deficient and IL-4-overexpressing strains resisted rechallenge. These data imply that constitutive IL-4 expression delays or suppresses the development of a virus-specific cytotoxic lymphocyte population important in clearing primary RSV infection.
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Parikh AA, Salzman AL, Fischer JE, Szabó C, Hasselgren PO. Interleukin-1 beta and interferon-gamma regulate interleukin-6 production in cultured human intestinal epithelial cells. Shock 1997; 8:249-55. [PMID: 9329125 DOI: 10.1097/00024382-199710000-00003] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Recent studies suggest that interleukin-6 (IL-6) is produced in the intestinal mucosa during sepsis and endotoxemia and that the enterocyte may be a source of IL-6 in these conditions. The regulation of IL-6 production in the enterocyte is not fully understood. We tested the hypothesis that IL-6 production in the enterocyte is regulated by proinflammatory cytokines. This was done by treating cultured Caco-2 cells, a transformed human intestinal epithelial cell line, with different concentrations of tumor necrosis factor-alpha (TNF-alpha), IL-1 beta, IL-6 or interferon-gamma (IFN-gamma). IL-6 production by the Caco-2 cells was determined by ELISA. The expression of IL-6 mRNA was determined by reverse-transcriptase polymerase chain reaction. IL-6 was not produced in unstimulated Caco-2 cells. Treatment of the Caco-2 cells with IL-1 beta resulted in a dose- and time-dependent stimulation of IL-6 production with a maximal effect noted at an IL-1 beta concentration of .5 ng/mL at 24 h. IFN-gamma alone did not stimulate IL-6 production but potentiated the effect of IL-1 beta in a synergistic fashion. Treatment of the Caco-2 cells with IL-1 beta induced expression of IL-6 mRNA with a response noticed after 30 min. TNF-alpha and IL-6 did not influence the production of IL-6 in the Caco-2 cells. The results suggest that enterocyte IL-6 production is stimulated by IL-1 beta and that this effect is potentiated by IFN-gamma. The regulation of IL-6 production in the enterocyte may be specific for IL-1 beta, since neither TNF nor IL-6 stimulated IL-6 production.
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Archer SB, Burnett RJ, Flesch LV, Hobler SC, Bower RH, Nussbaum MS, Fischer JE. Implementation of a clinical pathway decreases length of stay and hospital charges for patients undergoing total colectomy and ileal pouch/anal anastomosis. Surgery 1997; 122:699-703; discussion 703-5. [PMID: 9347845 DOI: 10.1016/s0039-6060(97)90076-3] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND Clinical pathways are increasingly being used by hospitals to improve efficiency in the care of certain patient populations; however, little prospective data are available to support their use. This study examined whether using a clinical pathway for patients undergoing ileal pouch/anal anastomosis, a complex procedure in which we had extensive practical experience, affected hospital charges or length of stay (LOS). METHODS A clinical pathway was developed to serve patients undergoing elective total colectomy and ileal pouch/anal anastomosis. All operations were performed by two attending physicians (J.E.F., M.S.N.). Before implementation, 10 pilot patients were prospectively monitored to ensure that hospital charges were accurately generated. In addition, charge audits were performed by an outside agency to verify the accuracy of the hospital bills. The pathway was then implemented, and 14 patients were prospectively analyzed. RESULTS In all patients the principal diagnosis was ulcerative colitis, with the exception of three patients with familial polyposis. Mean external audit charges were within 2% of the hospital bills; therefore the hospital bills were used in all calculations. The mean LOS decreased from 10.3 days to 7.5 days (p = 0.046) for patients on the pathway versus pilot patients. Mean hospital charges also decreased significantly, from $21,650 to $17,958 per patient (p = 0.005). CONCLUSIONS Implementation of a clinical pathway, even for an operation in which the surgeon has much experience, is an effective method for reducing LOS and charges for patients. This is likely the result of interdisciplinary cooperation, elimination of unnecessary interventions, and streamlined involvement of ancillary services. These results support the development of clinical pathways for procedures that involve routine preoperative and postoperative care. In addition, the benefits of clinical pathways should increase proportionally with increasing case volume for a particular procedure.
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Fang CH, Li BG, Wang JJ, Fischer JE, Hasselgren PO. Insulin-like growth factor 1 stimulates protein synthesis and inhibits protein breakdown in muscle from burned rats. JPEN J Parenter Enteral Nutr 1997; 21:245-51. [PMID: 9323685 DOI: 10.1177/0148607197021005245] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND Burn injury is associated with substantial whole-body protein loss, reflecting mainly a catabolic response in skeletal muscle. Recent studies suggest that treatment with insulin-like growth factor 1 (IGF-1) may reverse the catabolic response to burn injury, but the effects of IGF-1 on muscle protein synthesis and breakdown rates after burn injury are not known. We tested the hypothesis that IGF-1 blunts the catabolic response in skeletal muscle after burn injury by stimulating protein synthesis and inhibiting protein breakdown and that this effect of IGF-1 is caused by a direct effect on muscle tissue. METHODS Intact extensor digitorum longus muscles from burned, sham-burned, and untreated rats were incubated in the absence or presence of different concentrations of IGF-1. Total and myofibrillar protein breakdown rates were measured as net release of tyrosine and 3-methylhistidine, respectively. Protein synthesis rates were determined by measuring the incorporation of (U-14C)-phenylalanine into protein. RESULTS IGF-1 stimulated protein synthesis and inhibited protein breakdown in a dose-dependent fashion in muscles from burned and unburned rats. The maximal effect of IGF-1 on protein synthesis was seen at a hormone concentration of 100 ng/mL, whereas protein breakdown was further inhibited when the hormone concentration was increased to 1 microgram/mL. Ubiquitin messenger RNA (mRNA) levels were reduced by IGF-1 in incubated muscles, suggesting that IGF-1 may inhibit ubiquitin-dependent protein breakdown. CONCLUSIONS These results suggest that the anabolic effects of IGF-1 after burn may reflect inhibited protein breakdown and stimulated protein synthesis in skeletal muscle and that this response may be caused by a direct effect of IGF-1 on muscle tissue.
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Meyer TA, Wang JJ, Tiao GM, Ogle CK, Fischer JE, Hasselgren PO. Sepsis and endotoxaemia in mice stimulate the expression of interleukin-I and interleukin-6 in the central nervous system. Clin Sci (Lond) 1997; 92:519-25. [PMID: 9176027 DOI: 10.1042/cs0920519] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
1. In previous studies, experimental endotoxaemia was found to stimulate cytokine production in the central nervous system. The effect of sepsis on brain cytokines is not fully known. We compared the effect of endotoxaemia and sepsis on brain interleukin-1 and interleukin-6 expression. 2. Male A/J mice were injected subcutaneously with lipopolysaccharide (10 mg/kg) or an equal volume of saline as control. Sepsis was induced by caecal ligation and puncture (CLP); control mice underwent sham-operation. Brain tissue was assayed for interleukin-1 and interleukin-6 by ELISA. Northern blotting or the polymerase chain reaction was used to determine cytokine mRNA levels. 3. Administration of endotoxin induced a greater than fourfold increase in brain interleukin-1, a greater than threefold increase in interleukin-6 and an increase in mRNA for both cytokines. Caecal ligation and puncture resulted in increased brain interleukin-1 and interleukin-6 levels, but the changes were less pronounced and occurred later than after injection of endotoxin. There was no detectable difference in brain interleukin-1 mRNA between septic and sham-operated mice, whereas interleukin-6 mRNA was increased in brains of septic animals. 4. Sepsis and endotoxaemia resulted in similar, although not identical, changes in brain interleukin-1 and interleukin-6 concentrations and mRNA levels, suggesting that increased cytokine production in the central nervous system is part of the systemic response to sepsis and may be mediated by endotoxin.
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Tang YW, Neuzil KM, Fischer JE, Robinson FW, Parker RA, Graham BS. Determinants and kinetics of cytokine expression patterns in lungs of vaccinated mice challenged with respiratory syncytial virus. Vaccine 1997; 15:597-602. [PMID: 9178456 DOI: 10.1016/s0264-410x(96)00214-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The development of a successful respiratory syncytial virus (RSV) vaccine will be advanced by an improved understanding of the pathogenesis of natural disease and vaccine-enhanced illness. Using a murine model, we have examined cytokine message expression and cytokine secretion in lungs of mice primed with killed or live antigens and challenged with RSV. Stable cytokine mRNA expression was achieved if the prime-challenge interval was 2 weeks. The pattern of expression of interleukin-4 (IL-4) and interferon-7 (IFN-gamma 1 mRNA was established by day 4 after challenge and was maintained at least through day 12, and was not affected by the concentration of priming immunogen or virus challenge. An enzyme-linked immunospot assay demonstrated that CD4+ T cells were responsible for the production of IL-4, while many cell types secreted IFN-gamma. These experiments begin to define the kinetics of cytokine expression and phenotypes of cytokine-producing cells following RSV infection, supporting previous findings that suggested aberrant infiltration of CD4+ T lymphocytes and excessive IL-4 secretion may play a role in the vaccine-enhanced disease associated with RSV.
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Sheriff S, Chance WT, Fischer JE, Balasubramaniam A. Neuropeptide Y treatment and food deprivation increase cyclic AMP response element-binding in rat hypothalamus. Mol Pharmacol 1997; 51:597-604. [PMID: 9106624 DOI: 10.1124/mol.51.4.597] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Intrahypothalamic (IHT) administration of neuropeptide Y (NPY) induces a robust feeding response in rats. We have shown previously that NPY-induced feeding is mediated by a pertussis-toxin-sensitive G protein in rats. NPY receptors are coupled to cAMP and Ca2+. Because these second messengers are known to activate cAMP response element binding proteins, (CREB), cAMP response element modulators, or activating transcription factor 1, we investigated the involvement of these transcription factors in NPY-induced feeding in rats. Compared with control injections of cerebrospinal fluid (1 microl), IHT administration of NPY increased cAMP response element (CRE) binding to rat hypothalamic nuclear extracts in a time-dependent manner, as detected by an electrophoretic mobility shift assay. In contrast, IHT administration of the anorectic neuropeptide, pituitary adenylate cyclase activating polypeptide, strongly inhibited the CRE binding. Food deprivation for 48 hr also increased CRE binding, whereas 8 hr of refeeding normalized CRE activity. Preincubation of the hypothalamic nuclear extracts of NPY-treated and unfed rats with antibody specific to CREB blocked CRE binding, whereas preincubation with phosphoCREB antibody retarded the migration of CRE-protein complex, indicating that phosphoCREB is involved in this process. Consistently, immunohistochemical studies with food-deprived rats showed an intense phosphoCREB signal in the paraventricular nuclei and ventromedial hypothalamus in comparison to rats fed ad libitum. Hypothalamic calcium/calmodulin-dependent protein kinase II activity was also increased by IHT-NPY. These results suggest that calcium/calmodulin-dependent protein kinase II induced phosphorylation of CREB may be involved in regulating feeding behavior induced by NPY.
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Zuo L, Ogle CK, Fischer JE, Nussbaum MS. mRNA differential display of colonic mucosa cells in ulcerative colitis. J Surg Res 1997; 69:119-27. [PMID: 9202657 DOI: 10.1006/jsre.1997.5041] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Involvement of mucosal cells in inflammatory bowel disease (IBD) may be a sequenced process and the molecular difference between involved and uninvolved cells might implicate a possible mechanism in the disease process. The aim of this study was to compare gene expression between involved and uninvolved colonic mucosa cells in an individual with ulcerative colitis (UC) and to clone, sequence, and identify those differentially expressed genes, mRNA differential display was used to identify the gene expression in the mucosa of the UC patient. Anchored oligo(dT) primers and random 5' oligonucleotide 10-mer were used to carry out polymerase chain reaction on reverse-transcribed RNA (RT-PCR). The amplified cDNAs were displayed on a standard sequencing gel and comparisons were drawn between each two lanes representing either involved or uninvolved cells from a specific combination of two primers. Wherever differences were noted between lanes, the bands were reamplified using PCR, cloned into specialized vectors for positive selection, and then confirmed by dot blot. The cloned genes were then sequenced and compared with the GenBank database. About 1200 mRNA species were displayed in the sequencing gel. Among them, 106 fragments were differentially expressed between the two groups. Twenty-five of those differentially displayed gene fragments have been isolated, reamplified, and cloned for sequencing and dot blot analysis. Seventeen of the fragments were differentially expressed using the dot blot technique. Among those 25 gene fragments, 14 have homology to known genes and 11 have no match to any reported genes. Those matched known genes included genes for parathyroid tumor, T cell receptor-beta, alpha-nascent polypeptide-associated complex, ovarian cancer, and myeloblast. This is the first study using mRNA differential display to observe differential gene expression between involved and uninvolved mucosa cells in UC and it shows that differential display is a rapid method for characterizing gene changes in vivo in ulcerative colitis. The results from this study may provide useful information and facilitate further gene studies in this disease.
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Parikh AA, Salzman AL, Kane CD, Fischer JE, Hasselgren PO. IL-6 production in human intestinal epithelial cells following stimulation with IL-1 beta is associated with activation of the transcription factor NF-kappa B. J Surg Res 1997; 69:139-44. [PMID: 9202660 DOI: 10.1006/jsre.1997.5061] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Recent studies suggest that interleukin-1 beta (IL-1 beta) stimulates interleukin-6 (IL-6) production in human intestinal epithelial cells, but the intracellular mechanisms of this response are not known. In other reports, the nuclear factor-kappa B (NF-kappa B) regulated IL-6 production in certain cell types. We tested the hypothesis that IL-6 production in the enterocyte is associated with activation of NF-kappa B. Caco-2 cells, a human intestinal epithelial cell line, were grown in tissue culture whereafter they were treated with IL-1 beta (0.5 ng/ml). Cells were preincubated with pyrrolidine dithiocarbamate (PDTC; 10-500 microM), tosyl-lys-chloromethylketone (TLCK; 10-500 microM), or genistein (25-75 microM), all of which are known inhibitors of NF-kappa B. IL-6 levels in the culture media were measured after 24 hr by enzyme-linked immunosorbent assay (ELISA) and IL-6 messenger RNA (mRNA) levels were determined after 4 hr by competitive reverse-transcriptase polymerase chain reaction (RT-PCR). NF-kappa B activity was determined by electrophoretic gel mobility shift assay (EMSA). PDTC, TLCK, and genistein each inhibited IL-1 beta-induced IL-6 production by the Caco-2 cells in a dose-dependent fashion. These responses were also associated with a decrease in IL-6 mRNA levels. There was no NF-kappa B activity in untreated cells, but the addition of IL-1 beta resulted in the activation of NF-kappa B as determined by EMSA. The results suggest that IL-1 beta-induced IL-6 production in the enterocyte is associated with activation of NF-kappa B. The inhibition of IL-6 production by the NF-kappa B inhibitors indicates that the IL-6 production is regulated by NF-kappa B, although further experiments are needed to test that hypothesis.
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Noguchi Y, James JH, Fischer JE, Hasselgren PO. Increased glutamine consumption in small intestine epithelial cells during sepsis in rats. Am J Surg 1997; 173:199-205. [PMID: 9124626 DOI: 10.1016/s0002-9610(96)00012-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND Previous reports have emphasized increased intestinal glutamine consumption during sepsis. This may be of clinical significance as glutamine is a (and perhaps the) physiologic fuel for the intestine. A problem remains, however, as glutaminase, the major enzyme for the degradation of glutamine, is decreased rather than increased in sepsis. This implies an alteration in the metabolic fate of glutamine in sepsis, which may be of clinical significance. METHODS We determined the effect of sepsis on glutamine metabolism in mucosa of small intestine. Sepsis was induced in rats by cecal ligation and puncture. Control rats were sham-operated. After 16 hours, glutamine consumption was measured in isolated enterocytes, and glutaminase, glutamine synthetase, and glutamine transaminase activities and DNA synthesis were determined in mucosa. RESULTS Glutamine consumption was increased during sepsis in enterocytes from the tips of the villi and was unchanged in enterocytes from the midportions of the villi and the crypts. As previously shown, mucosal glutaminase activity was reduced. However, glutamine synthetase and glutamine transaminase activities were stimulated in septic rats, suggesting an increase in metabolism of glutamine via alternate pathways. DNA synthesis was increased during sepsis, especially in crypt cells. CONCLUSIONS Increased or unchanged glutamine consumption in enterocytes from septic rats, despite reduced glutaminase activity, appears to reflect increased activity of other enzyme systems and/or increased utilization of the amino acid for DNA and protein synthesis. Since other aspects of glutamine metabolism may also be deranged in sepsis, a continual enteral supply of glutamine to the intestinal lumen during sepsis may be clinically useful.
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Tiao G, Lieberman M, Fischer JE, Hasselgren PO. Intracellular regulation of protein degradation during sepsis is different in fast- and slow-twitch muscle. THE AMERICAN JOURNAL OF PHYSIOLOGY 1997; 272:R849-56. [PMID: 9087646 DOI: 10.1152/ajpregu.1997.272.3.r849] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We tested the hypothesis that the difference in the response to sepsis of protein breakdown between fast- and slow-twitch skeletal muscle reflects differential activation of the energy-ubiquitin-dependent proteolytic pathway. In addition, we defined the time course and the tissue specificity of sepsis-induced changes in the expression of the ubiquitin pathway. Sepsis was induced in rats by cecal ligation and puncture; control rats were sham operated. Energy-dependent protein breakdown was measured in incubated extensor digitorum longus (EDL) and soleus muscles. Ubiquitin mRNA levels were determined by Northern blot analysis. Sepsis resulted in increased energy-dependent protein breakdown and upregulated expression of ubiquitin mRNA in the fast-twitch EDL but not in the slow-twitch soleus muscle. The sepsis-induced increase in ubiquitin mRNA levels in the EDL muscle was noticeable before the increase in energy-dependent protein breakdown. Sepsis increased ubiquitin mRNA levels in the diaphragm (a mixed fiber-type muscle) but not in heart, liver, kidney, or intestine, consistent with a tissue-specific regulation of the ubiquitin system during sepsis. The results suggest that the difference in protein breakdown during sepsis between fast- and slow-twitch muscles reflects differential activation of the energy-ubiquitin-dependent proteolytic pathway. The data also suggest that the expression of the ubiquitin pathway is upregulated in a time-dependent fashion during sepsis and that this response is not a generalized phenomenon but is tissue specific.
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Griffen FD, Fischer JE. Practice guidelines and liability implications. BULLETIN OF THE AMERICAN COLLEGE OF SURGEONS 1997; 82:29-33. [PMID: 10166192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
It should be clear that the authors of this article are not enamored of practice guidelines, thinking them of much more potential harm than good. On the other hand, if practice guidelines are deemed essential, then they must be written with the goal of quality patient care advocacy and with an eye toward the possible damage they may do.
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