Cell type-specific variations in the induction of hsp70 in human leukocytes by feverlike whole body hyperthermia

Fever has been associated with shortened duration and improved survival in infectious disease. The mechanism of this beneficial response is still poorly understood. The heat-inducible 70-kDa heat shock protein (Hsp70) has been associated with protection of leukocytes against the cytotoxicity of inflammatory mediators and with improved survival of severe infections. This study characterizes the induction of Hsp70 by feverlike temperatures in human leukocytes in vitro and in vivo. Using flow cytometry, Hsp70 expression was determined in whole blood samples. This approach eliminated cell isolation procedures that would greatly affect the results. Heat treatment of whole blood in vitro for 2 hours at different temperatures revealed that Hsp70 expression depends on temperature and cell type; up to 41 degrees C, Hsp70 increased only slightly in lymphocytes and polymorphonuclear leukocytes. However, in monocytes a strong induction was already seen at 39 degrees C, and Hsp70 levels at 41 degrees C were 10-fold higher than in the 37 degrees C control. To be as close as possible to the physiological situation during fever, we immersed healthy volunteers in a hot water bath, inducing whole body hyperthermia (39 degrees C), and measured leukocyte Hsp70 expression. Hsp70 was induced in all leukocytes with comparable but less pronounced cell type-specific variations as observed in vitro. Thus, a systemic increase of body temperature as triggered by fever stimulates Hsp70 expression in peripheral leukocytes, especially in monocytes. This fever-induced Hsp70 expression may protect monocytes when confronted with cytotoxic inflammatory mediators, thereby improving the course of the disease.

Release of non-neuronal acetylcholine from the human placenta: difference to neuronal acetylcholine

The synthesis and release of non-neuronal acetylcholine, a widely expressed signaling molecule, were investigated in the human placenta. This tissue is free of cholinergic neurons, i.e. a contamination of neuronal acetylcholine can be excluded. The villus showed a choline acetyltransferase (ChAT) activity of 0.65 nmol/mg protein per h and contained 500 nmol acetylcholine/g dry weight. In the absence of cholinesterase inhibitors the release of acetylcholine from isolated villus pieces amounted to 1.3 nmol/g wet weight per 10 min corresponding to a fractional release rate of 0.13% per min. The following substances did not significantly modify the release of acetylcholine: oxotremorine (1 microM), scopolamine (1 microM), (+)-tubocurarine (30 microM), forskolin (30 microM), ouabain (10 microM), 4alpha-phorbol 12,13-didecanoate (1 microM) and tetrodotoxin (1 microM). Removal of extracellular calcium, phorbol 12,13-dibutyrate (1 microM) and colchicine (100 microM) reduced the acetylcholine release between 30% and 50%. High potassium chloride (54 mM and 108 mM) increased the acetylcholine release slightly (by about 30%). A concentration of 10 microM nicotine was ineffective, but 100 microM nicotine enhanced acetylcholine release gradually over a 50-min period without desensitization of the response. The facilitatory effect of nicotine was prevented by 30 microM (+)-tubocurarine. Inhibitors of cholinesterase (physostigmine, neostigmine; 3 microM) facilitated the efflux of acetylcholine about sixfold, and a combination of both (+)-tubocurarine (30 microM) and scopolamine (1 microM) halved the enhancing effect. In conclusion, release mechanisms differ between non-neuronal and neuronal acetylcholine. Facilitatory nicotine receptors are present which are activated by applied nicotine or by blocking cholinesterase. Thus, cholinesterase inhibitors increase assayed acetylcholine by two mechanisms, protection of hydrolysis and stimulation of facilitatory nicotine receptors.

A controlled study of sorbent suspension dialysis in chronic liver disease and hepatic encephalopathy

To investigate the role of extracorporeal detoxification in cirrhotic patients with advanced hepatic encephalopathy not responding to medical treatment, 20 patients were randomized to receive six hours of additional sorbent dialysis or ongoing standardized medical treatment. Following treatment, the clinical stage of encephalopathy remained unchanged in both groups. Abnormal sensory evoked potentials improved following sorbent dialysis (N70 latency, 128 ms before versus 110 ms after treatment, P<0,05; cervico-cranial transmission, 7.7 ms versus 6.8 ms, P<0.01) indicating improvement in important aspects of cerebral function. In contrast, brain function remained unchanged following medical treatment (N70 latency, 114 ms versus 113 ms; cervico-cranial transmission, 7.7 ms versus 7.2 ms, P=NS, respectively). Serum benzodiazepine levels decreased significantly after sorbent dialysis but not after medical treatment. Biocompatibility of sorbent dialysis was limited and clinical complications occurred in a proportion of patients. In conclusion, a six-hour treatment with sorbent suspension dialysis did not ameliorate the clinical stage of HE but improved neurophysiologic function in cirrhotic patients who had not responded to conventional medical treatment.

Oral feeding with glutamine prevents lymphocyte and glutathione depletion of Peyer's patches in endotoxemic mice

OBJECTIVE

To determine the effect of oral glutamine feeding on lymphocyte subpopulations and glutathione metabolism in Peyer's patches (PPs) of healthy and endotoxemic mice.

SUMMARY BACKGROUND DATA

Recent data indicate that nutrients both maintain nitrogen and energy balances and modulate cell and organ function. In particular, glutamine has an impact on gut and immune function. This is of special importance in the perioperative phase.

METHODS

Female Balb/c mice were fed a glutamine-enriched diet or a control diet for 10 days. On day 7 25 microg lipopolysaccharide (LPS) or saline was injected. On day 3 after the challenge, mice were killed, total cell yield was determined, and lymphocyte subpopulations (total T cells, CD4+, CD8+ cells, and B cells) were analyzed by flow cytometry. One experimental group was treated with buthionine sulfoximine, a specific inhibitor of glutathione synthesis. The glutathione content in PPs was measured by high-performance liquid chromatography.

RESULTS

Glutamine administration led to a significant increase in total cell yield, including T and B cells, in PPs. The LPS-induced reduction of T cells (-45%) and of B cells (-30%) was significantly lower in glutamine-treated mice. Endotoxemia caused a 42% decrease of glutathione in control animals, but not in glutamine-treated animals. As with LPS, buthionine sulfoximine also lowered lymphocyte numbers and glutathione content of the PPs.

CONCLUSIONS

Administration of glutamine prevents LPS-stimulated lymphocyte atrophy in PPs, possibly by increasing the glutathione content in the PPs. Therefore, oral glutamine supply seems to be a suitable approach for improving intestinal immunity in immunocompromised patients.

Postoperative glycyl-glutamine infusion reduces immunosuppression: partial prevention of the surgery induced decrease in HLA-DR expression on monocytes

BACKGROUND AND AIMS

Surgery, trauma and inflammation reduce HLA-DR expression on monocytes, which is associated with an increased susceptibility to infection and sepsis. Furthermore, surgery decreases plasma glutamine (GLN) levels. The expression of HLA-DR on human monocytes in vitro is dependent on the concentration of GLN in the culture medium. We therefore hypothesized that postoperative infusions of glutamine-dipeptides would prevent the decreased HLA-DR expression on monocytes.

METHODS

Thirty patients undergoing major abdominal surgery were randomly allocated to receive either 1500 ml Vamin (control) or an isonitrogenic formulation containing Vamin and 500 ml glycyl-glutamine (35 g GLN; 0.5g/kg BW) (GLY-GLN), or Vamin and 500 ml alanyl-glutamine (35 g GLN; 0.5 g/kg BW) (ALA-GLN) as a continuous infusion over 48 h post-operatively. Immediately and 48 h after surgery blood samples were collected to determine HLA-DR expression on monocytes by flow cytometry.

RESULTS

The groups were comparable with respect to age, gender distribution and operation time. In patients receiving GLY-GLN mean HLA-DR expression on monocytes at 48 h was significantly better preserved than in controls (65.0 %+/-7 % vs 42.5 %+/-4 %;P<0.05), whereas HLA-DR expression on monocytes in patients receiving ALA-GLN was not significantly different.

CONCLUSION

This is the first study comparing the dipeptides GLY-GLN and ALA-GLN in the postoperative setting. The GLY-GLN induced preservation of HLA-DR on monocytes following surgery may prevent infectious complications in these patients.

Relationship between interleukin-6 plasma concentration in patients with sepsis, monocyte phenotype, monocyte phagocytic properties, and cytokine production

Monocyte phenotype, their phagocytic capacity as well as the cytokine production from 10 patients with sepsis with low interleukin-6 (IL-6) serum concentrations (<1000 pg/mL) and 8 patients with sepsis with high IL-6 (> or = 1000 pg/mL) plasma concentrations were investigated within 24 hours of fulfilling the criteria for sepsis. Monocytes from patients with high IL-6 levels had higher levels of human leukocyte antigen (HLA)-DR, HLA-ABC, CD64, and CD71, and the production of tumor necrosis factor-alpha (TNF-alpha) and IL-8, as well as the capacity of monocytes to phagocytose, was significantly elevated. Of 8 patients with high levels of plasma IL-6, 4 patients died. In contrast, all 10 patients with low plasma IL-6 concentrations survived until day 28. Patients who died had constant high IL-6 concentrations during the first 3 days, whereas IL-6 levels in patients who survived decreased by 88%. Our data indicate that IL-6 levels are a better prognostic parameter in the early phase of sepsis than the monocyte HLA-DR expression.

Different transendothelial migration behaviour pattern of blood monocytes derived from patients with benign and malignant diseases of the breast

BACKGROUND

In this study we compared the expression of selected monocyte surface antigens with the potential to transmigrate through an endothelial layer before and after surgery from breast cancer patients (CA) and patients with benign disease of the breast (BE).

MATERIALS AND METHODS

Transmigration capacity of mononuclear cells was determined after isolation by Ficoll density gradient, layered over human umbilical vein endothelial cells and cultured in a two chamber plate added with fMLP as a chemotactic stimulus. We determined monocyte phenotye (HLA-DR, FcgRI/CD64, CR1/CD11b and LFA-1/CD11a) and the phagocytosis of E. coli by flow cytometry.

RESULTS

Before surgery blood monocytes had an equal expression of the measured surface antigens, but were different in regard to their interaction with endothelial cells. Monocytes derived from CA had a higher transmigration potency than those of BE. Moreover, the migration through the endothelial cell layer created different populations of monocytes. Surgical stress modified transmigrated monocytes of BE into the direction of monocytes from CA. Phagocytic capacity of peripheral blood monocytes from CA was significantly diminished and was further reduced after surgery when measured in transmigrated cells.

CONCLUSION

Our study shows that monocytes from CA and BE can be discriminated in regard to their interaction with endothelial cells.

Lipopolysaccharide causes atrophy of Peyer's patches and an increased expression of CD28 and B7 costimulatory ligands

Intestinal mucosal dysfunction appears to contribute to infectious complications in critically ill patients. The current study was undertaken to investigate whether endotoxin affects lymphocyte subpopulations and the expression of costimulatory signals in Peyer's patches (PP). Female Balb/c mice were given an intraperitoneal injection of 25 microg LPS and sacrified 24 h or 72 h later to determine total cell yield, lymphocyte subpopulations (B-cells, total T-cells, CD4+- and CD8+-cells), the costimulatory molecules CD28, B7.1 (CD80) and B7.2 (CD86) and the percentage of apoptotic cells in PP and in the spleen as well as small intestinal IgA concentration. Lipopolysaccharide (LPS) challenge caused a significant decrease of total cell yield in PP at both time-points (-50+/-28% and -43+/-25%, respectively; P < 0.001). This decrease was significant for all measured lymphocyte subpopulations. In contrast, total cell yield was increased (P < 0.001) in the spleen 24 h (+52+/-13%) and 72 h (+130+/-22%) after LPS. The decrease of lymphocyte numbers in the PP was accompanied by an increased percentage of lymphocytes expressing costimulatory molecules. In this respect, an increased percentage of CD40+CD80+, CD40+CD86+, and of CD4+CD28+ could be demonstrated after LPS administration. In the spleen, the percentage of CD4+CD28+ was also elevated after LPS bolus, however, the percentage of CD40+CD80+ was reduced, and that of CD40+CD86+ was unaltered. The influence of LPS on apoptosis of lymphocytes was time-dependent. The percentage of apoptotic cells 24 h after LPS was increased in PP (P < 0.01), but was unchanged in the spleen. Seventy-two hours after LPS injection, the percentage of apoptotic cells returned to normal in PP. Luminal IgA levels remained unchanged after LPS challenge. In conclusion, our data show that LPS causes atrophy of PP which seems to be counterregulated by an enhanced expression of costimulatory molecules.

Tumor antigen pulsed dendritic cells enhance the cytolytic activity of tumor infiltrating lymphocytes in human hepatocellular cancer

OBJECTIVE

Tumor infiltrating lymphocytes (TILs) stimulated with interleukin-2 (IL-2) ex vivo have been successfully used therapeutically in some cancer patients, but their potency in eliciting an effective anti-tumor response is variable. We have tried to augment killing activity of tumor infiltrating lymphocytes derived from hepato-cellular carcinoma (HCC) using autologous monocytes derived dendritic cells.

METHODS

Tumor infiltrating lymphocytes (TILs) from 6 patient with hepatocellular carcinoma were isolated and the phenotype were further characterized. From the same patients, autologous dendritic cells were generated from CD14+ monocytes that were cultured for 6 days in the presence of granulocyte macrophage colony-stimulating factor (GM-CSF) and interleukin 4 (IL-4). Those professional antigen presenting cells were pulsed with whole autologous hepatoma tumor lysates (pDC). TILs were cocultured with pDC or unpulsed DC. To assess the cytotoxic potency of TILs, the ability to lyse the tumor cell targets K652, Daudi and an allogeneic HCC celline was determined in a standard cytotoxic assay.

RESULTS

Tumor cells targets in vitro are poorly lysed by tumor infiltrating lymphocytes indicating T-cell hyporesponsiveness. In contrast, the killing activity of HCC derived TILs against Daudi (9.15% +/- 7.5) and allogeneic HCC tumor target (18.2% +/- 9.2) could be significantly augmented when stimulated with pDC (Daudi: 38% +/- 6.8 and allogeneic HCC: 55% +/- 10). The killing activity of TILs against K562 was unaffected by pDC.

CONCLUSION

The low cytotoxic activity profile of HCC derived TILs in vitro can be increased by tumor lysate pulsed dendritic cells and may therefore be more effective in vivo when used for adoptive immunotherapy.

[Contribution of the Kansas technique for reducing complications of mature cataract surgery]

PURPOSE

We report our experience with the Kansas technique of phakosection which eliminates or limits most complications of classic manual extracapsular extraction.

PATIENTS AND METHODS

This retrospective study included our first 80 patients undergoing surgery for mature cataract between May 1996 and May 1998 where we used the Kansas technique. We compared outcome with a group of 30 patients who underwent classic manual extracapsular extraction in a study performed in 1995 by the same surgeon in the same hospital.

RESULTS

Per- and post-operative complications were significantly lower with phakosection. Functional rehabilitation was quicker, better and provided better patient comfort.

DISCUSSION

Despite some difficulties encountered in a public hospital (viscoelastic excessively fluid and in small quantity, lack of suitable knives or reuse of sterilized disposable knives), we found that the Kansas technique is very well adapted to mature cataracts and our working conditions.

CONCLUSION

Phakosection allowed us to give our patients with mature or very mature cataracts the benefit of small incisions. With a moderate increase in cost, this technique significantly reduced our per- and post-operative complication rates and gave quicker and better visual recovery. In our countries, this technique provides better care than phakoemulsification.

Endothelial cells downregulate expression of the 70 kDa heat shock protein during hypoxia

Hsp70 is induced by hypoxia in most mammalian cell types and contributes to their ability to survive hypoxic episodes. However, little is known about Hsp70 expression in the hypoxia-tolerant endothelial cells (ECs). We investigated the effect of hypoxia on Hsp70 in human microvascular endothelial HMEC-1 cells. Reduction of pO(2) to 2.5% of normal for 20 h stimulated lactate production and the activity of glycolytic enzymes. This metabolic adaptation to hypoxia was accompanied by a remarkable reduction of Hsp70 on the protein level and on the mRNA level. Approximately 12 h after the hypoxic period Hsp70 expression reached pre-hypoxia levels again. Since ECs are adapted to the low oxygen tension of the vasculature they are confronted with a supraphysiological oxygen level during in vitro culture. We suppose that the high Hsp70 under these conditions reflects a stress response which disappears at the more physiological reduced oxygen tension during hypoxia.

Influence of enteral diets supplemented with key nutrients on lymphocyte subpopulations in Peyer's patches of endotoxin-boostered mice

BACKGROUND AND AIMS

This study was undertaken to compare the effect of different key nutrients on lymphocyte subsets of Peyer's patches (PP) and spleen in endotoxemic mice.

METHODS

Female Balb/c mice were fed over a period of 10 days either with an isocaloric and isonitrogenous control diet (Control), a glutamine enriched diet (Diet I) or a diet containing glutamine, arginine, glycine, and n-3 fatty acids (Diet II). On day 7 the mice were challenged intraperitoneally with 25 microg LPS. The lymphocyte subpopulations (B cells, T cells, CD4+ and CD8+) of PP and spleen were analysed by flow cytometry. Glutathione content of small intestinal mucosa and spleen was determined by HPLC and luminal small intestinal IgA by ELISA.

RESULTS

Both experimental diets increased the number of B and T cells in the PP and that of T cells in the spleen (P<0.01). Glutathione content in PP and spleen was higher under administration of key nutrients (P<0.05). Diet II reduced luminal small intestinal IgA content in comparison to the two other groups.

CONCLUSION

The addition of arginine, glycine and n-3 fatty acids to a glutamine supplemented diet does not enhance lymphocyte numbers in PP and spleen, but reduces intestinal IgA content.

Severe acute pancreatitis causes alterations in HLA-DR and CD14 expression on peripheral blood monocytes independently of surgical treatment

OBJECTIVE

To find out if the severity of acute pancreatitis or the surgical treatment of severe acute pancreatitis influences HLA-DR and CD14 expression on peripheral blood monocytes.

DESIGN

Prospective open study.

SETTING

University hospital, Austria.

SUBJECTS

9 consecutive patients with severe acute pancreatitis in need of operative treatment, 5 patients with mild acute pancreatitis, and 7 healthy volunteers.

INTERVENTIONS

Samples of 5 ml blood were taken daily into endotoxin free tubes at same time points. Surgical treatment for severe acute pancreatitis consisted of blunt necrosectomy, operative lavage, laparostomy, and open drainage.

MAIN OUTCOME MEASURES

Correlation between HLA-DR and CD14 expression on peripheral blood monocytes on the one hand and the severity of acute pancreatitis and operative treatment of severe acute pancreatitis, on the other.

RESULTS

In patients with severe acute pancreatitis expression of HLA-DR and CD14 was significantly downregulated both before and after operation (p < 0.0001; ANOVA), compared with patients with mild acute pancreatitis or healthy controls. However the expression of the two cell surface markers was not affected either by the first operation, or by the reoperations.

CONCLUSION

These findings suggest that in acute pancreatitis the expression of cell surface markers on peripheral blood monocytes is related to the severity of disease but is not influenced by operative treatment.

Testdiagnostische Verfahren zur Überprüfung der Fertigkeiten im Lesen, Rechtschreiben und Rechnen. Eine kritische Übersicht

Zusammenfassung: Fragestellung: Die Diagnose einer umschriebenen Entwicklungsstörung schulischer Fertigkeiten kann nur auf der Grundlage individuell angewendeter standardisierter Testverfahren zur Prüfung von Schulleistungen und IQ erfolgen. Um dem Untersucher die Auswahl geeigneter Verfahren zu erleichtern, soll eine kritische Übersicht deutschsprachiger Verfahren zur Erfassung von Rechtschreib-, Lese- und Rechenfertigkeiten gegeben werden.Methodik: Testintention und Gütekriterien der Schulleistungstests werden zusammenfassend dargestellt. Die Verfahren werden hinsichtlich ihrer Brauchbarkeit zur Legasthenie- und Dyskalkuliediagnostik bewertet. Ergänzend werden Vorschläge zur klinischen Prüfung gegeben. Ergebnis: Zusammenfassend stehen jenseits des Grundschulbereichs nicht ausreichend aktuell normierte und den gängigen Gütekriterien genügende Verfahren zur Verfügung. Insbesondere zur Prüfung von Rechenfertigkeiten muss jenseits der 4. Klasse auf Verfahren zurückgegriffen werden, deren curriculare Gültigkeit zweifelhaft ist. Die letzten Klassenstufen der Haupt- und Realschule sind dann wieder besser abgedeckt. Schlussfolgerungen: Es kann ein deutlicher Bedarf an Neukonstruktionen bzw. Aktualisierungen publizierter Schulleistungstests festgestellt werden.

[Diagnostic testing methods for skill assessment in reading, writing, and arithmetic. A critical review]

OBJECTIVES

The diagnosis of a specific developmental disorder of reading, writing and arithmetic can be made based upon individually applied standardized methods for testing scholastic achievement and IQ. To make the choice of suitable methods easier for the administrator of the test, a critical survey of German-language methods for assessing skills in reading, writing and arithmetic is presented.

METHODS

Test intention and psychometric properties for scholastic achievement are summarized. The methods are assessed with regard to their utility in the diagnosis of congenital alexia and dyscalculia. Supplementary suggestions for clinical assessment are given.

RESULTS

In summary, beyond the primary school area there is a lack of current standardized methods that meet the current standards of quality. Particularly the assessment of arithmetic skills above those of the 4th grade level require resorting to methods of dubious curricular validity. Coverage is once again better for the upper elementary and middle school levels.

CONCLUSIONS

There is a need for new constructions, respectively a need to update published scholastic achievement tests.

Therapeutic potential of glutathione

Reactive oxygen species, formed in various biochemical reactions, are normally scavenged by antioxidants. Glutathione in its reduced form (GSH) is the most powerful intracellular antioxidant, and the ratio of reduced to oxidised glutathione (GSH:GSSG) serves as a representative marker of the antioxidative capacity of the cell. Several clinical conditions are associated with reduced GSH levels which as a consequence can result in a lowered cellular redox potential. GSH and the redox potential of the cell are components of the cell signaling system influencing the translocation of the transcription factor NF kappa B which regulates the synthesis of cytokines and adhesion molecules. Therefore, one possibility to protect cells from damage caused by reactive oxygen species is to restore the intracellular glutathione levels. Cellular GSH concentration can be influenced by exogenous administration of GSH (as intravenous infusion or as aerosol), of glutathione esters or of GSH precursors such as glutamine or cysteine (in form of N-acetyl-L-cysteine, alpha-lipoic acid). The modulation of GSH metabolism might present a useful adjuvant therapy in many pathologies such as intoxication, diabetes, uremia, sepsis, inflammatory lung processes, coronary disease, cancer and immunodeficiency states.

Post-feeding hyperammonaemia in patients with transjugular intrahepatic portosystemic shunt and liver cirrhosis: role of small intestinal ammonia release and route of nutrient administration

BACKGROUND

Hyperammonaemia is a pathogenetic factor for hepatic encephalopathy that may be augmented after a transjugular intrahepatic portosystemic shunt (TIPS). Experimental data suggest that hyperammonaemia may be caused to a large extent by metabolism of small intestinal enterocytes rather than colonic bacteria.

AIMS

To evaluate if ammonia release and glutamine metabolism by small intestinal mucosa contribute to hyperammonaemia in vivo in patients with liver cirrhosis.

METHODS

Using TIPS to examine mesenteric venous blood, we measured mesenteric venous-arterial concentration differences in ammonia and glutamine in patients with liver cirrhosis before, during, and after enteral (n = 8) or parenteral (n = 8) isonitrogenous infusion of a glutamine containing amino acid solution.

RESULTS

During enteral nutrient infusion, ammonia release increased rapidly compared with the post-absorptive state (65 (58-73) v. 107 (95-119) micromol/l after 15 min; mean (95% confidence interval)) in contrast with parenteral infusion (50 (41-59) v. 62 (47-77) micromol/l). This resulted in a higher portal ammonia load (29 (21-36) v. 14 (8-21) mmol/l/240 minutes) and a higher degree of systemic hyperammonaemia (14 (11-17) v. 9 (6-12) mmol/l/240 minutes) during enteral than parenteral infusion. The mesenteric venous-arterial concentration difference in glutamine changed from net uptake to release at the end of the enteral infusion period (-100 (-58 to -141) v. 31 (-47-110) micromol/l) with no change during parenteral nutrition.

CONCLUSIONS

These data suggest that small intestinal metabolism contributes to post-feeding hyperammonaemia in patients with cirrhosis. When artificial nutrition is required, parenteral nutrition may be superior to enteral nutrition in patients with portosystemic shunting because of the lower degree of systemic hyperammonaemia.

Resting energy expenditure in short-term starvation is increased as a result of an increase in serum norepinephrine

BACKGROUND

The effects of food restriction on energy metabolism have been under investigation for more than a century. Data obtained are conflicting and research has failed to provide conclusive results.

OBJECTIVE

The objective of this study was to test the hypothesis that in lean subjects under normal living conditions, short-term starvation leads to an increase in serum concentrations of catecholamines and thus to an increase in resting energy expenditure.

DESIGN

Resting energy expenditure, measured by indirect calorimetry, and hormone and substrate concentrations were measured in 11 healthy, lean subjects on days 1, 2, 3, and 4 of an 84-h starvation period.

RESULTS

Resting energy expenditure increased significantly from 3.97 +/- 0.9 kJ/min on day 1 to 4.53 +/- 0.9 kJ/min on day 3 (P < 0.05). The increase in resting energy expenditure was associated with an increase in the norepinephrine concentration from 1716. +/- 574 pmol/L on day 1 to 3728 +/- 1636 pmol/L on day 4 (P < 0.05). Serum glucose decreased from 4.9 +/- 0.5 to 3.5 +/- 0.5 mmol/L (P < 0.05), whereas insulin did not change significantly.

CONCLUSIONS

Resting energy expenditure increases in early starvation, accompanied by an increase in plasma norepinephrine. This increase in norepinephrine seems to be due to a decline in serum glucose and may be the initial signal for metabolic changes in early starvation.

Catecholamines up-regulate lipopolysaccharide-induced IL-6 production in human microvascular endothelial cells

The catecholamine-mediated modulation of the cytokine network has primarily been demonstrated for leukocytes. Whereas catecholamines decrease the LPS-induced production of IL-6 by leukocytes, serum levels of IL-6 are dramatically increased by the catecholamine epinephrine in animal endotoxemia models. We now demonstrate that epinephrine as well as norepinephrine can induce IL-6 in an endothelial cell line (HMEC-1). Furthermore, these catecholamines could even potentiate the LPS-induced IL-6 protein production. The synergistic effect of catecholamines and LPS could be reproduced in primary human skin microvascular endothelial cells. The catecholamine-induced IL-6 stimulation is based on increased IL-6 mRNA levels. RNA stability assays revealed that this regulation is not a result of enhanced RNA stability and therefore is most likely due to an increased transcription. Treatment with cycloheximide indicated that new protein synthesis is not necessary for this transcriptional up-regulation of IL-6 mRNA. Preincubation with alpha and beta receptor antagonists showed that the effect is mediated by beta(1)- and beta(2)-adrenergic receptors. Thus, endothelial cells might be a possible source of increased IL-6 production observed in situations such as stress or septic shock, in which catecholamines are elevated due to endogenous production or exogenous application.

Crucial role of TNF-alpha in CD8 T cell-mediated elimination of 3LL-A9 Lewis lung carcinoma cells in vivo

The role of perforin, IFN-gamma, and TNF-alpha in anti-tumor CD8 T cell immunity was examined in a new tumor model using a CD8 T cell epitope (GP33) derived from lymphocytic choriomeningitis virus as a tumor-associated Ag. In contrast with parental 3LL-A9 (A9) Lewis lung carcinoma cells that progressively grow in C57BL/6 mice, s.c. injection of GP33-transfected A9GP33 tumor cells induced a protective GP33-specific CD8 T cell response that led to complete tumor cell elimination. Tumor regression was dependent on perforin, IFN-gamma, or TNF-alpha, because A9GP33 tumors developed in mice deficient in one of these genes. A9GP33 tumors arising in perforin- and IFN-gamma-deficient mice represented GP33 Ag-loss variants, demonstrating that GP33-specific CD8 T cells from these mice were able to exert an Ag selection pressure. In contrast, tumor cells growing in TNF-alpha knock-out mice still expressed the tumor-associated GP33 peptide despite the presence of activated GP33-specific CD8 T cells. These findings provide evidence for a crucial role of TNF-alpha in A9 tumor cell elimination by CD8 T cells in vivo.

Influence of short-term protein malnutrition of mice on the phenotype and costimulatory signals of lymphocytes from spleen and Peyer's patches

The objective of this study was to investigate the impact of short-term protein malnutrition (PM) on immunoglobulin A (IgA) production and on the number and phenotype of lymphocytes in Peyer's patches (PP) and in the spleen. Balb/c mice were fed for 4, 7, or 10 d with a protein-deficient diet (0.1% protein). We determined B lymphocytes (CD40(+)), T lymphocytes (CD3(+)), T-helper (CD4(+)), and T-suppressor (CD8(+)) cells and the expression of costimulatory signals B7.1 (CD80) and B7.2 (CD86) on B cells and their counter receptors CD28 and CTLA-4 on T cells by fluorescence-activated cell-sorting analysis. Luminal IgA concentration in the small intestine was determined by an enzyme-linked immunosorbent assay. Four days of PM caused a significant reduction in the number of mononuclear cells in the spleen (5.6 x 10(7) +/- 1 x 10(7) versus 2. 4 x 10(7) +/- 0.5 x 10(7), P < 0.001) and the PP (13 x 10(6) +/- 3 x 10(6) versus 8.6 x 10(6) +/- 2 x 10(6), P < 0.01). There was a relative increase of T cells in the spleen and a relative increase of B cells in the PP. Luminal IgA content of small intestine was significantly reduced after 4 d of PM (242 +/- 55 microg versus 173 +/- 39 microg, P < 0.05) and remained at about this level until day 10 of PM. Four days after PM, the costimulatory signals B7.1 and B7. 2 on B cells were upregulated in the PP but markedly downregulated in the spleen, which was inversely related to the expression of the counter receptor CD28 on T-helper cells. We conclude that short-term PM increases the activation of B cells in the PP but reduces the relative number and activation state of splenic B cells. Only 4 d of PM caused a systemic and intestinal immunodepression, as indicated by a markedly decreased content of mononuclear cells in the PP and the spleen.

Reversible ageusia as an effect of clopidogrel treatment

In two patients we observed a loss of taste during clopidogrel treatment which was reversible.

Polytrauma induces increased expression of pyruvate kinase in neutrophils

Polytrauma (PT) leads to systemic activation of polymorphonuclear neutrophils (PMNs). Organ damage commonly found in these patients is ascribed to respiratory bursts of activated PMNs. With the use of sodium dodecyl sulfate-polyacrylamide gel electrophoresis, PMN extracts from PT patients were found to contain a clear protein band not seen in control PMNs from healthy volunteers. This band was identified by amino acid sequencing and Western blotting as pyruvate kinase (PK). Enzymatic assays revealed a 600-fold increase in PK activity in PMNs of PT patients, with the highest levels occurring between the fifth and seventh posttraumatic day. In lymphocytes, no such increase was detectable. As PK is a major regulatory enzyme in glycolysis, glucose-dependent lactate production in PMNs from PT patients was assayed. These cells showed a higher glycolytic lactate production than controls. It was additionally demonstrated that acute activation of respiratory burst activity depends mainly on breakdown of glucose to lactate via the pentose-phosphate pathway and glycolysis. In PMNs from PT patients, this glucose-dependent respiratory burst activity was more than twofold higher than in controls. The increase in expression and activity of PK in PMNs from PT patients may contribute to the high glucose-dependent respiratory burst activity seen in these cells.