Hand hygiene compliance in nursing home wards: the effect of increased accessibility of alcohol-based hand rub

BACKGROUND

Elderly nursing home residents are vulnerable to infection from micro-organisms. Hand hygiene is considered one of the most important measures to prevent transmission.

AIM

To determine the effect of increased accessibility to alcohol-based hand rub (ABHR) in nursing home wards by monitoring hand hygiene compliance (HHC) among healthcare workers (HCWs).

METHODS

An 11-month intervention study was conducted in a Danish six-ward nursing home. Data were collected using an automatic hand hygiene monitoring system (AHHMS). After a baseline period, one extra ABHR dispenser was placed in each of the 150 apartments. Baseline HHC was compared with the HHC during an immediate intervention period and a long-term intervention period.

FINDINGS

A total of 159 HCWs were included. The AHHMS registered 341,078 hand hygiene opportunities. Overall baseline HHC was 31% (95% confidence interval: 30-32). A significant +18% absolute immediate effect (first five months) (95% CI: 17-19; P < 0.0001) and +13 percentage points (95% CI: 11-14; P < 0.0001) long-term effect (another four months) were recorded. HCWs working day shifts and short-term employees had a higher baseline HHC than HCWs working evening/night shifts. However, HCWs working night shifts achieved the greatest long-term effect with a mean +27 percentage point difference (P < 0.0001).

CONCLUSION

Placing an additional ABHR dispenser strategically within staff workflow significantly increased HHC among HCWs, demonstrating a noteworthy effect. The study is the first to report the effect on nursing home dispenser accessibility as a single intervention and to show a significant unmet potential.

Changes in circulating inflammatory markers following febrile non-haemolytic transfusion reactions to leucoreduced red cells

It would be desirable to be able to distinguish fever as a result of febrile non-haemolytic transfusion reactions (FNHTR) from other febrile conditions. To further characterize the inflammatory feature of FNHTR, we measured a large panel of inflammatory markers in pre- and posttransfusion plasma samples from patients with and without FNHTR following the transfusion of leucoreduced red blood cells. As FNHTR patients only displayed a significant increase in IL-6, we conclude that changes in plasma cytokine levels during FNHTR are unlikely to be used diagnostically. An incidental finding of a distinct cytokine pattern in pretransfusion samples from FNHTR patients warrants further investigations, as it might be used to characterize the nature of FNHTR and to predict the risk of these adverse events.

Three-year follow-up of implementation of evidence-based transfusion practice in a tertiary hospital

BACKGROUND AND OBJECTIVES

Traditionally, Denmark has had a high rate of allogeneic red blood cell transfusion caused by a liberal transfusion practice despite the existence of restrictive guidelines. We established a Patient Blood Management programme in a tertiary hospital and report the results of the implementation of evidence-based transfusion practice.

MATERIALS AND METHODS

Red blood cell transfusion quality indicators were compared with the evidence-based guideline at hospital and department level. Based on this evaluation, wards were selected for interventions targeting doctors and nurses. The implementation process was monitored by transfusion quality and utilization data over a 3-year period with totally 166 341 admissions in 98 960 mixed, adult medical and surgical patients.

RESULTS

At the hospital level, transfusion above the upper guideline limit decreased from 23 to 10% (P < 0·001), and transfusion at or below the restrictive haemoglobin trigger of 7·3 g/dl increased from 7 to 19% (P < 0·001). The percentage of single-unit transfusions increased from 72 to 78% (P < 0·001), and the majority of transfusion rates and volumes decreased significantly. Red cell use decreased with 41% in surgical procedures and 28% in admissions (P < 0·001).

CONCLUSION

The intervention was associated with a significant and sustained overall increase in compliance with national guidelines for red blood cell transfusion for non-bleeding patients, and led to significantly fewer patients being exposed to transfusion.

Towards an exposure-dependent model of post-traumatic stress: longitudinal course of post-traumatic stress symptomatology and functional impairment after the 2011 Oslo bombing

BACKGROUND

Our understanding of the dynamics of post-traumatic stress symptomatology and its link to functional impairment over time is limited.

METHOD

Post-traumatic stress symptomatology (Post-traumatic Checklist, PCL) was assessed three times in 1-year increments (T1, T2, T3) following the Oslo bombing of 22 July, 2011, in directly (n = 257) and indirectly exposed (n = 2223) government employees, together with demographics, measures of exposure and work and social adjustment. The dynamics of post-traumatic stress disorder symptom cluster interplay were examined within a structural equation modelling framework using a cross-lagged autoregressive panel model.

RESULTS

Intrusions at T1 played a prominent role in predicting all symptom clusters at T2 for the directly exposed group, exhibiting especially strong cross-lagged relationships with avoidance and anxious arousal. For the indirectly exposed group, dysphoric arousal at T1 played the most prominent role in predicting all symptom clusters at T2, exhibiting a strong relationship with emotional numbing. Emotional numbing seemed to be the main driver behind prolonged stress at T3 for both groups. Functional impairment was predominately associated with dysphoric arousal and emotional numbing in both groups.

CONCLUSIONS

For directly exposed individuals, memories of the traumatic incident and the following intrusions seem to drive their post-traumatic stress symptomatology. However, as these memories lose their potency over time, a sequela of dysphoric arousal and emotional numbing similar to the one reported by the indirectly exposed individuals seems to be the main driver for prolonged post-traumatic stress and functional impairment. Findings are discussed using contemporary models within an exposure-dependent perspective of post-traumatic stress.

Mean Diffusional Kurtosis in Patients with Glioma: Initial Results with a Fast Imaging Method in a Clinical Setting

BACKGROUND AND PURPOSE

Diffusional kurtosis imaging is an MR imaging technique that provides microstructural information in biologic systems. Its application in clinical studies, however, is hampered by long acquisition and postprocessing times. We evaluated a new and fast (2 minutes 46 seconds) diffusional kurtosis imaging method with regard to glioma grading, compared it with conventional diffusional kurtosis imaging, and compared the diagnostic accuracy of fast mean kurtosis (MK') to that of the widely used mean diffusivity.

MATERIALS AND METHODS

MK' and mean diffusivity were measured in the contrast-enhancing tumor core, the perifocal hyperintensity (indicated on T2 FLAIR images), and the contralateral normal-appearing white and gray matter of 34 patients (22 with high-grade and 12 with low-grade gliomas). MK' and mean diffusivity in the different tumor grades were compared by using a Wilcoxon rank sum test. Receiver operating characteristic curves and the areas under the curve were calculated to determine the diagnostic accuracy of MK' and mean diffusivity.

RESULTS

MK' in the tumor core, but not mean diffusivity, differentiated high-grade from low-grade gliomas, and MK' differentiated glioblastomas from the remaining gliomas with high accuracy (area under the curveMK' = 0.842; PMK' < .001). MK' and mean diffusivity identified glioblastomas in the group of high-grade gliomas with similar significance and accuracy (area under the curveMK' = 0.886; area under the curvemean diffusivity = 0.876; PMK' = .003; Pmean diffusivity = .004). The mean MK' in all tissue types was comparable to that obtained by conventional diffusional kurtosis imaging.

CONCLUSIONS

The diffusional kurtosis imaging approach used here is considerably faster than conventional diffusional kurtosis imaging methods but yields comparable results. It can be accommodated in clinical protocols and enables exploration of the role of MK' as a biomarker in determining glioma subtypes or response evaluation.

The effects of a novel metabotropic glutamate receptor 5 antagonist (AZD2066) on transient lower oesophageal sphincter relaxations and reflux episodes in healthy volunteers

BACKGROUND

Selective metabotropic glutamate receptor 5 (mGluR5) antagonists inhibit transient lower oesophageal sphincter relaxations (TLESRs) in animals and acid reflux in humans.

AIM

To assess the effect of single doses of the mGluR5 antagonist AZD2066 on TLESRs and reflux in humans.

METHODS

Healthy male volunteers received AZD2066 13 mg and placebo (part A), or AZD2066 2 mg and AZD2066 6 mg and placebo (part B), in a randomised crossover study. Postprandial manometry/pH-impedance measurements were taken after each dose.

RESULTS

A total of 13 individuals completed part A of the study and 19 individuals completed part B. There was a significant reduction in the geometric mean number of TLESRs (27%; P = 0.02) and the geometric mean number of reflux episodes (51%; P = 0.01) in subjects receiving AZD2066 13 mg compared with placebo. Adverse events in participants receiving AZD2066 13 mg were mostly related to the nervous system [dizziness (3/13); disturbance in attention (3/13)]. Adverse events were reversible and of mild intensity. There were no serious adverse events. The effects of AZD2066 appeared dose-dependent, with smaller reductions in TLESRs and reflux episodes (relative to placebo) and fewer adverse events observed for AZD2066 2 mg and AZD2066 6 mg compared with AZD2066 13 mg.

CONCLUSION

The mGluR5-mediated inhibition of TLESRs may be a useful approach for inhibiting gastro-oesophageal reflux.

Causes of death among diabetic patients in Denmark

AIMS/HYPOTHESIS

To study the distribution of causes of death in the Danish population, and its variation by diabetes status, sex, age and calendar year as well as the years of life lost from the specific causes of death.

METHODS

Persons aged 30-98 years were followed from 1995 to 2008 by linkage of Danish registers. Poisson regression was used to model cause-specific mortality rates by age and calendar time for each specific cause of death, according to sex and diabetes status. The mortality rates were also modelled as a function of age and birth cohort. We computed the distribution of causes of death and years of life lost from specific causes of death due to diabetes.

RESULTS

During the 14-year study period, patients with diabetes contributed 2.3 million person-years of follow-up and 124,210 deaths, whereas persons without diabetes contributed 45.1 million person-years and 648,020 deaths. The mortality was higher among individuals with diabetes, and the mortality ratio (diabetes vs no diabetes) decreased with age and for all causes and cardiovascular diseases also by calendar time. The effect of sex on the association between diabetes and mortality varied with age and cause of death. About 9 years of life were lost to diabetes at age 30 years, and 3 years at age 70 years.

CONCLUSIONS/INTERPRETATION

Age-specific mortality is higher among people with diabetes, and rate ratios vary with age, sex, calendar period and cause of death. The distribution of causes of death was similar for persons with and without diabetes.

Bioimpedance spectroscopy: a new tool to assess early esophageal changes linked to gastroesophageal reflux disease?

Bioimpedance spectroscopy can identify pathological changes related to precancerous lesions of the cervix uteri and esophagus. It therefore has the potential to detect early reflux-related changes in the esophageal mucosa, such as dilated intercellular spaces. The reliable detection of dilated intercellular spaces at the time of endoscopy would yield a significant diagnostic advantage for separating patients with functional heartburn from the large proportion of patients with gastroesophageal reflux symptoms but no macroscopic esophagitis or pathological acid exposure. The bioimpedance of the esophageal mucosa, measured with a small caliber probe, was evaluated in a series of preclinical experiments. First, sections of rabbit esophageal epithelium were mounted in Ussing chambers and exposed to solutions at pH 7.4 or pH 1.5 for 45 minutes. Impedance measurements were taken at varying probe pressures. Second, rabbit esophageal epithelia were perfused for 45 minutes in situ with pH 1.1 or control solutions and impedance measurements taken. Samples from both in vitro and in situ experiments were taken for morphological examination by light microscopy. Finally, esophageal bioimpedance was measured in awake dogs with permanent esophagocutaneous stoma. The in situ experiments demonstrated that morphological changes in the esophageal mucosa could be discerned by the use of bioimpedance spectroscopy. The variability in resistivity was species-independent but was affected by the pressure applied to the probe. The results suggest that evaluation of bioimpedance spectroscopy for use in a clinical setting is warranted. Small morphological differences in the esophageal mucosa may be detected by the use of bioimpedance spectroscopy.

Randomised clinical trial: the efficacy of a transient receptor potential vanilloid 1 antagonist AZD1386 in human oesophageal pain

BACKGROUND

Many patients with gastro-oesophageal reflux disease (GERD) are hypersensitive to heat and acid and may respond insufficiently to standard treatment. Antagonists of the heat and acid receptor 'transient receptor potential vanilloid 1'(TRPV1) are a potential drug class for GERD treatment.

AIM

To investigate the effect of a TRPV1 antagonist (AZD1386) on experimentally induced oesophageal pain.

METHODS

Twenty-two healthy men (20-31 years) participated in this randomised, placebo-controlled, double-blinded, crossover study examining the effects of a single-dose oral AZD1386 (30 and 95 mg). Subjects were block-randomised. On treatment days, participants were stimulated with painful heat, distension, electrical current and acid in the oesophagus. Heat and pressure pain on the forearm were somatic control stimuli.

DATA ANALYSIS

intention-to-treat.

RESULTS

A total of 21 participants completed the protocol and 1 voluntarily discontinued. In the oesophagus, both 30 and 95 mg of AZD1386 increased pain thresholds to heat stimuli 23% [95% confidence interval (CI): 10-38%] and 28%, respectively (CI: 14-43%). The skin heat tolerance was increased 2.1 °C (CI: 1.1-3.2 °C) after 30 mg AZD1386 and 4.0 °C (CI: 3.0-5.0 °C) after 95 mg. Heat analgesia persisted for 2.5 h. Pain thresholds to the other stimuli were unaffected by AZD1386. 50% reported 'feeling cold' and body temperature increased in all subjects exposed to 30 and 95 mg AZD1386 (mean increase 0.4±0.3 °C and 0.7±0.3 °C, respectively, P<0.05).

CONCLUSIONS

AZD1386 increased oesophageal and skin heat pain thresholds and had a safe adverse-event profile. This drug class may have a potential for treatment of GERD.

Relationships between body mass index and short-circuit current in human duodenal and colonic mucosal biopsies

AIM

Retrospectively, to investigate the relationship between body mass index (BMI) and basal electrogenic transport as measured by short-circuit current (SCC) in human duodenal and colonic mucosal biopsies.

METHODS

The study included biopsies from mucosa of normal appearance in the sigmoid colon and/or distal duodenum. Patients were referred for routine endoscopy (predominantly for monosymptomatic abdominal pain) and had normal endoscopic findings. Biopsies were mounted in miniaturized Ussing chambers and basal SCC was recorded. Patients were divided into two groups on the basis of BMI (≤25 and >25 kg m⁻²). Statistical significance was assessed by the unpaired t-test or Wilcoxon rank-sum test. Correlation coefficients were calculated by Pearson product moment correlation.

RESULTS

In colonic biopsies, basal SCC (mean ± standard deviation) was significantly higher in 59 biopsies from 30 patients with low BMI than in 32 biopsies from 23 patients with high BMI (45 ± 29 μA cm⁻² vs. 27 ± 21 μA cm⁻², P = 0.016). In duodenal biopsies, mean basal SCC was numerically lower in 38 biopsies from 15 patients with low BMI than in 46 biopsies from 19 patients with high BMI (54 ± 26 μA cm⁻² vs. 74 ± 39 μA cm⁻², P = 0.069). The correlation coefficient between BMI and SCC was -0.26 (P = 0.06) in colonic biopsies and +0.44 (P = 0.001) in duodenal biopsies.

CONCLUSION

Basal intestinal active electrogenic transport is related to BMI and this relationship may differ in different segments of the intestinal tract.

Serotonin and superior mesenteric artery resistance index

OBJECTIVE

Serotonin is a vasoactive neuroendocrine substance and serotonergic drugs are promising agents for the treatment of functional gastrointestinal disorders. The effect of serotonin on superior mesenteric blood flow in humans is unknown. The aim of this study was to examine the effect of exogenous serotonin on superior mesenteric artery blood flow, as estimated by the resistance index with Doppler ultrasound, in healthy human volunteers.

MATERIAL AND METHODS

Six fasting healthy adult volunteers of both genders were studied. Transabdominal Doppler ultrasound was used to evaluate the effects of either a standard meal or intravenous infusion of serotonin (2.5-20 nmol kg-1 min-1) on the superior mesenteric artery resistance index, platelet-depleted plasma levels of serotonin, blood pressure, heart rate and electrocardiogram.

RESULTS

All subjects had the same patterns of response to meal and serotonin stimulation. Meal stimulation decreased the mean resistance index from 0.84+/-0.04 to 0.72+/-0.02 (p = 0.0004) and increased platelet-depleted-plasma levels of serotonin from 50+/-36 to 61+/-46 nmol L-1 (p = 0.04). Serotonin stimulation increased the mean resistance index from 0.82+/-0.04 to 0.88+/-0.03 (p = 0.006) and mean platelet-depleted-plasma levels of serotonin from 44+/-24 to 83+/-37 nmol L-1 (p = 0.03). Most subjects reported minor short-lived adverse effects. Electrocardiogram results were unchanged during all examinations.

CONCLUSIONS

We conclude that intravenous infusion of serotonin increases the resistance index of the superior mesenteric artery (increases downstream resistance) in healthy adult volunteers.

Effect of serotonin on small intestinal contractility in healthy volunteers

The physiological significance of serotonin released into the intestinal lumen for the regulation of motility is unknown in humans. The aim of this study was to evaluate the effect of serotonin infused into the lumen of the gastric antrum, duodenum or the jejunum, on antro-duodeno-jejunal contractility in healthy human volunteers. Manometric recordings were obtained and the effects of either a standard meal, continuous intravenous infusion of serotonin (20 nmol/kg/min) or intraluminal bolus infusions of graded doses of serotonin (2.5, 25 or 250 nmol) were compared. In addition, platelet-depleted plasma levels of serotonin, blood pressure, heart rate and electrocardiogram were evaluated. All subjects showed similar results. Intravenous serotonin increased migrating motor complex phase III frequency 3-fold and migrating velocity 2-fold. Intraluminal infusion of serotonin did not change contractile activity. Platelet-depleted-plasma levels of serotonin increased 2-fold following both intravenous and high doses of intraluminal infusions of serotonin. All subjects reported minor short-lived adverse effects following intravenous serotonin stimulation, while only half of the subjects reported minor short-lived adverse effects following intraluminal serotonin stimulations. We conclude that exogenous serotonin in the lumen of the upper part of the small intestine does not seem to change antro-duodeno-jejunal contractility significantly in healthy adult volunteers.

Transfusion-related inhibition of cytokines (TRICK). Experimental transfer of neutralizing autoantibodies to interleukin-6 by plasma transfusions

BACKGROUND

For some unknown reason humans may 'spontaneously' produce high amounts of neutralizing autoantibodies to a number of growth factors and cytokines. Reaching a certain high level the antibodies render the person cytokine deficient, mostly without overt clinical manifestations. The autoantibodies in question are detectable in normal immunoglobulin preparations and correspondingly in normal human plasma for transfusion. High affinity neutralizing autoantibodies to interleukin-6 (aAb-IL-6) are present in high titres in 0.1% of plasma from blood donors. Using aAb-IL-6 as a model we here report the first study addressing transfer of cytokine autoantibodies with blood components.

MATERIALS AND METHODS

We transferred high amounts of aAb-IL-6 to two patients suffering from end-stage disease of multiple myeloma. This was done by serial transfusions with normal human plasma highly positive for aAb-IL-6. We assessed recovery and kinetics of the transferred aAb-IL-6 and exposed how the recipients' plasma IL-6 bound to aAb-IL-6.

RESULTS

Free IL-6 was detectable in plasma of the recipients before transfusion. After the first transfusion IL-6 became immune complexed to aAb-IL-6 the molar plasma concentrations of which exceeded total IL-6 at least 500 times.

CONCLUSION

The observations signify that high amounts of neutralizing autoantibodies to cytokines (in this context aAb-IL-6) are occasionally transferred by transfusion. Although neither beneficial nor obvious detrimental effects of the plasmas were observed in this study our measurements evidently uncover a hitherto unknown form of transfusion-related immune modulation: transfusion-related inhibition of cytokines (TRICK). Depending on the cytokine autoantibody in question, the phenomenon might affect immune responses to infection and recovery after stem cell transplantation.

Structural brain abnormalities in early onset first-episode psychosis

BACKGROUND

Brain morphometry in children and adolescents with first-episode psychosis offer a unique opportunity for pathogenetic investigations.

METHODS

We compared high-resolution 3D T1-weighted magnetic resonance images of the brain in 29 patients (schizophrenia, schizotypal disorder, delusional disorder or other non-organic psychosis), aged 10-18 to those of 29 matched controls, using optimized voxel-based morphometry.

RESULTS

Psychotic patients had frontal white matter abnormalities, but expected (regional) gray matter reductions were not observed. Post hoc analyses revealed that schizophrenia patients (n = 15) had significantly larger lateral ventricles as compared to controls. Duration and dose of antipsychotics correlated negatively with global gray matter volume in minimally medicated patients (n = 18).

CONCLUSION

Findings of white matter changes and enlarged lateral ventricles already at illness onset in young schizophrenia spectrum patients, suggests aberrant neurodevelopmental processes in the pathogenesis of these disorders. Gray matter volume changes, however, appear not to be a key feature in early onset first-episode psychosis.

Duodenal secretion in humans mediated by the EP4 receptor subtype

AIM

Assessment of functional EP receptor subtypes involved in PGE2-induced secretion in human duodenum. The spectrum of activities by PGE2 in mammals, including cytoprotective bicarbonate secretion in duodenum, is mediated through four G protein-coupled receptor subtypes (EP1-EP4).

METHODS

Biopsies from the second part of duodenum from patients undergoing endoscopy were mounted in modified Ussing chambers. Basal and stimulated short circuit current (SCC) and slope conductance (SG) were measured. Dose-response relations for PGE2 and subtype receptors EP1/EP3 (sulprostone), EP2 (butaprost), and EP4 (1-OH PGE1) were assessed by cumulated doses of single agonists.

RESULTS

PGE2 caused a dose-dependent increase in SCC, maximum 101 +/- 20 microA cm(-2) with an EC50 of 35.6 +/- 5.8 nm (n = 3). Likewise 1-OH PGE1 caused a dose-dependent SCC increase, maximum 63.3 +/- 28.6 microA cm(-2) with an EC50 of 56.7 +/- 7.2 nm (n = 3). 1-OH PGE1 at 500 nm increased SCC by 18.0 +/- 3.0 microA cm(-2) (n = 10) and SG by 2.9 +/- 0.4 mS cm(-2) (n = 6). Sulprostone (n = 6) and butaprost (n = 6) had no effects on SCC or SG. SCC was inhibited 31.4 +/- 13.2% (n = 10) by bumetanide (25 microM serosa) and 18.6 +/- 5.8% (n = 10) by acetazolamide (250 microM lumen). Diphenylamine-2-carboxylate (DPC) (250 microM mucosa) and SITS (10 microM mucosa) had almost no effect.

CONCLUSIONS

Effects of PGE2 on secretion in the second part of human duodenum is mediated through the EP4 receptor and not through EP1, EP2, or EP3.

Transfusion practice in massively bleeding patients: time for a change?

BACKGROUND AND OBJECTIVES

We identified some fatal cases where massively bleeding patients received inadequate transfusion therapy. The aim of this study was to review and evaluate the transfusion practice in acutely multitransfused patients.

MATERIALS AND METHODS

Patients receiving > 10 units of red blood cells (RBC) within 24 h of admission and 30 blood components within 7 days of admission were reviewed.

RESULTS

Thirty-nine patients were identified, 13 of whom were inadequately transfused (IT) and had a higher mortality (12/13) than adequately transfused (AT) patients 13/26 (P = 0.013). Ten of 13 IT patients developed a microvascular bleed compared to four of 26 in the AT group (P = 0.001) and had a lower platelet count upon arrival at the intensive care unit (40 x 10(9)/l vs. 80 x 10(9)/l, P = 0.024).

CONCLUSIONS

An early balanced transfusion therapy is vital in massively bleeding patients, and a pro-active approach from the blood bank is warranted. We have introduced an acute transfusion package (ATP) consisting of 5 RBC, 5 FFP and 2 PC units, indicated in massively bleeding patients, securing a balanced transfusion therapy.

Functional characterization of muscarinic receptor subtypes in human duodenal secretion

AIM

Acetylcholine (ACh) stimulates ion secretion in the small intestine and colon. The purpose of the present study was to characterize the ACh-induced electrogenic ion transport in human duodenum and determine the muscarinic receptor subtypes functionally involved.

METHODS

Biopsies from the second part of duodenum were obtained from 28 patients during endoscopy. Biopsies were mounted in modified Ussing chambers with air-suction for measurements of short-circuit current by a previously validated technique. Short-circuit current was measured after application of chloride/bicarbonate transport inhibitors bumetanide, 4-acetamido-4'-isothiocyanostilbene-2,2'-disulfonic acid (SITS), diphenylamine-2-carboxylate (DPC), and acetazolamide. 4-diphenylacetoxy-N-methylpiperidine methiodide (4-DAMP) and two mamba toxins MT3 and MT7 were used to characterize the mAChR receptor subtypes involved. The effects of transport inhibitors and receptor antagonists were measured by comparing two consecutive responses of ACh on short-circuit current in the same biopsy specimen.

RESULTS

Bumetanide and 4-DAMP significantly inhibited ACh-induced short-circuit current, whereas SITS, DPC, acetazolamide, mamba toxin MT3, and mamba toxin MT7 all failed to show any significant effect.

CONCLUSION

In conclusion, our results indicate that muscarinic receptor subtype M3 acts as the main mediator of bumetanide-sensitive ACh-induced secretion in human duodenum.

TNF and LT binding capacities in the plasma of arthritis patients: effect of etanercept treatment in juvenile idiopathic arthritis

BACKGROUND

Etanercept (Enbrel) induces a rapid and sustained decline in disease activity in the majority of patients with refractory juvenile idiopathic arthritis (JIA). For unknown reasons, however, a number of JIA patients fail to respond to this therapy. During this treatment neutralisation of tumour necrosis factor (TNF, previously termed TNF alpha) and lymphotoxin (LT, previously termed TNF beta) may be mediated by etanercept itself as well as by naturally occurring soluble TNF receptors. In light of this, it was of interest to study the total TNF neutralizing capacity in plasma before and during treatment with etanercept.

RESULTS

In initial experiments plasma samples from healthy individuals were incubated with etanercept, and spiked with TNF or LT to a final concentration of 1000 pg/mL. Detection of TNF and LT by ELISA was found to be reduced by approximately 50% and 80% respectively, at a concentration of etanercept of 5-500 ng/mL, which is close to the pharmacological plasma concentrations. Plasma samples (n = 80) were then collected from 12 JIA patients (5 with pauciarticular, 5 with polyarticular and 2 with the systemic onset type) during treatment with etanercept (0.4 mg/kg twice weekly) for a period of 20.8 (15.6-23.9) months (median, range). The plasma samples were spiked with LT, and the inhibition of LT detection in ELISA was measured. In samples obtained 3 months after the start of etanercept, the inhibition of LT detection was augmented [72% (60-85)] compared with pre-treatment samples [16% (0.32)] (p = 0.0039). These findings were confirmed in binding assays using radiolabelled TNF. Among patients who responded insufficiently to therapy, reduced LT binding capacity, coinciding with flares of disease activity, was observed.

CONCLUSION

We have developed an assay by which LT binding capacity, reflecting the level of free, pharmacologically active etanercept, may be monitored in the blood of patients treated with etanercept. This assay may prove to be useful in guiding dose adjustments in patients with an incomplete response to etanercept.

Neurohumoral control of gastrointestinal motility

Neurohumoral substances and their receptors play a major part in the complex regulation of gastrointestinal motility and have therefore been the predominant targets for drug development. The numerous receptors involved in motility are located mainly on smooth muscle cells and neuronal structures in the extrinsic and intrinsic parts of the enteric nervous system. Within this system, receptor agonists and antagonists interacts directly to modify excitatory or inhibitory signals. In view of this complexity it is not surprising that our knowledge about the mechanisms of actions of the various neurohormones and drugs affecting gut motility has been rather fragmented and incomplete. However, recently substantial progress has been achieved, and drug therapy for gut dysmotility is emerging, based primarily on neurohumoral receptors. This paper presents a selective review of the neurohumoral regulatory mechanisms of gastrointestinal motility. In this context, the physiology and pharmacology of the smooth muscle cells, gastrointestinal motility and dysmotility, the enteric nervous system, gastrointestinal reflexes, and serotonin is presented. Further investigation and understanding of the transmitters and receptors involved in especially the reflex activation of peristalsis is crucial for the development of novel therapies for motility disorders.

Chromium allergy: significance of both Cr(III) and Cr(VI)

Most studies investigating chromium allergy have been performed with Cr(VI). However, real exposure to chromium from leather products includes both Cr(III) and Cr(VI). We have determined and compared the minimum elicitation threshold (MET) concentration for Cr(III) and Cr(VI) in Cr(VI)-sensitive patients. In addition, reactions to combinations of Cr(III) and Cr(VI) were compared to reactions elicited by Cr(III) and Cr(VI) alone. Dilution series of Cr(III) and Cr(VI) were applied in Finn Chambers on the back of 18 patients. The patches were left for 2 days and readings were done on days 2, 3 and 7. The MET10% for Cr(III) and Cr(VI) was calculated from the dose-response curves to be 0.18 microg/cm2/48 h (6 p.p.m.) and 0.03 microg/cm2/48 h (1 p.p.m.), respectively. No significant differences in the response to combined Cr(III) and Cr(VI) solutions versus single solutions were found. Cr(III) was concluded to play an important role in chromium allergy, because Cr(III) and Cr(VI) were both capable of eliciting eczema at low concentrations. Rather than regarding chromium dermatitis as a result of Cr(VI) allergy alone, it may be more correct to consider it as a result of a combined Cr(III) and Cr(VI) allergy.

Small intestinal manometry

Gastrointestinal motility is an integrated process including myoelectrical and contractile activity, tone, compliance and transit. The techniques for the assessment of gastrointestinal motility are multiple and all have their advantages and disadvantages. In the case of suspected abnormal upper gut transit, gastric and small bowel transit scintigraphy followed by small intestinal (antroduodenojejunalileal) manometry is recommended. Small bowel manometry can identify patterns suggestive of myopathy, neuropathy or obstruction. Information on procedures, indications, significance, pitfalls and guidelines for small bowel manometry is provided in this paper. In this context the potentials of small intestinal manometry for scientific experimental study of neurohumoral agents, such as serotonin receptor agonists and antagonists, on small intestinal motility is presented.

High circulating levels of biologically inactive IL-6/SIL-6 receptor complexes in systemic juvenile idiopathic arthritis: evidence for serum factors interfering with the binding to gp130

We previously demonstrated that high levels of IL-6/sIL-6R complexes are present in sera of patients with systemic juvenile idiopathic arthritis (s-JIA) and that the amount of IL-6 estimated in the IL-6/sIL-6R complexes is markedly higher than that measured by the B9 assay. Here, we show that two additional bioassays, employing human myeloma XG-1 cells and human hepatoma Hep3B cells, detected serum IL-6 levels similar to those measured by the B9 assay and approximately 10-fold lower than the IL-6 levels estimated to be present in the IL-6/sIL-6R complex. Using an assay for the measurement of the amount of circulating IL-6 complexed with the sIL-6R and available for binding to gp130 (gp130 binding activity), we show that the IL-6/gp130 binding activity is similar to that detected by the bioassays and again significantly lower than that estimated to be present in the IL-6/sIL-6R complex. Addition of recombinant human IL-6 (rhIL-6) to sera of patients or controls results in a markedly lower increase in the gp130 binding activity in patients than in controls. Moreover, sera from s-JIA patients inhibited in a dose dependent manner the gp130 binding activity assay. These results show that sera from patients with s-JIA contain a factor, or factors, that inhibit(s) the binding of the IL-6/sIL-6R complex to gp130. This inhibitory activity does not appear to be due to soluble gp130, C-reactive protein or autoantibodies to IL-6.

Assessing agreement between CD34 enumeration by flow cytometry and volumetric analysis

Prior to replacement of an established method for CD34 enumeration by an alternative approach, evaluation of the agreement between the methods is essential. In this study, the comparison of two assays was evaluated according to the recommendation of Bland and Altman describing the agreement between two methods where the true value is not known. CD34 enumeration was performed on blood or leukapheresis product from 105 patients by flow cytometry (dual platform assay) and volumetric analysis (single platform assay). Both the flow cytometric and the volumetric analysis showed poor reproducibility for measures lower than approximately 9 CD34+ cells/mm3. For values higher than 29 CD34+ cells/mm3, evaluation of the agreement demonstrated a difference between the single and dual platform assay, where CD34 enumeration by the volumetric analysis demonstrated values 73-80% of the flow cytometric value. The difference between the two assays could be due to several technical pitfalls which are discussed.

Neuropsychiatric aspects of Sotos syndrome. A review and two case illustrations

Sotos syndrome, also known as cerebral gigantism, is a rare growth disorder first described by Sotos and colleagues in 1964. Since then, a majority of the literature pertaining to Sotos syndrome has focussed on the medical aspects of the syndrome, while neuropsychiatric issues have been given little attention. The present article presents a review of the current knowledge concerning neuropsychiatric aspects of Sotos syndrome. Information is provided relating to physical appearance, intellectual impairment, learning disabilities, language impairments, behavioural disorders and outcome. It is emphasised that careful delineation of neuropsychiatric aspects within a diagnostic syndrome may turn out to be the first step towards molecular characterisation of behaviour.

Novel modified Ussing chamber for the study of absorption and secretion in human endoscopic biopsies

The aim of this study was to design and evaluate a modified Ussing chamber, that makes use of constant air suction (modified Ussing air suction chamber, MUAS) for fixation of biopsy specimens. Standard size forceps biopsies were taken from the descending part of duodenum from patients undergoing endoscopy. Short circuit current (SCC) and conductance (G) were measured during basal conditions and after addition of different sugars and secretagogues. Histologic examination was performed to determine the degree of tissue damage after study in the chamber. Basal SCC was 54.7 +/- 4.3 microA x cm(-2) and G was 58.7 +/- 4.7 mS x cm(-2) (mean +/- SEM, n=48) and steady values of these parameters were observed for at least 2 h. Reproducible and steady responses in SCC were obtained with D-glucose (SCCmax=172 +/- 22.1 microA x cm(-2); EC50=6.9 +/- 0.7 mM, n=5) and D-galactose (SCCmax=233 +/- 55.7 microA x cm(-2); EC50=9.2 +/- 0.7 mM, n=3), and secretory responses with 5-hydroxytryptamine, 100 microM (DeltaSCC= 16.1 +/- 3.8 microA x cm(-2), n=10), histamine, 100 microM (DeltaSCC=24.0 +/- 4.1 microA x cm(-2), n=10) and prostaglandin E2, 1 microM (DeltaSCC=30.3 +/- 5.4 microA x cm(-2), n=6). Experimental biopsy specimens showed intact surface epithelium by histologic examination and did not differ from controls apart from minor indications of edge damage. No difference in basal electrical parameters and D-glucose fluxes were found between Helicobacter pylori positive and negative patients. Our data suggests that the MUAS chamber represents a promising alternative approach to measure transport processes in intestinal endoscopic biopsies.

[Osteomyelitis. A rare and serious complication of inguinal hernia surgery]

We report two cases of osteomyelitis following herniotomy ad modum Lichtenstein with implantation of a polypropylene mesh. With the new prosthetic materials, the hernia recurrence rate and sick leave are reduced. In the case of persistent wound infection serious complications might occur.

Effects of indomethacin on Salmonella typhimurium- and cholera toxin-induced fluid accumulation in the porcine small intestine

The effect of the cyclooxygenase and prostaglandin E2 (PGE2) synthesis inhibitor, indomethacin, on the secretory responses induced by Salmonella serotype Typhimurium (ST) and cholera toxin (CT), in the porcine small intestine was investigated. ST (10(10) colony-forming units) and CT (56 micrograms) were instilled in tied-off intestinal loops in young anaesthetized pigs receiving intravenous indomethacin in a total dose of 7.5 mg/kg, or saline. The accumulated fluid in the loops and the luminal content of endogenous secretagogues PGE2 and 5-hydroxytryptamine (5-HT) were measured. ST induced fluid accumulation in the jejunum, whereas CT induced fluid accumulation in the jejunum and ileum. Indomethacin had no effect on the secretory responses. Indomethacin had a significant effect on the luminal content of PGE2 in jejunal ST and CT loops, whereas no effect of indomethacin was observed on the luminal content of 5-HT in ST and CT loops. In ST and CT loops, an increased content of PGE2 and 5-HT compared with test loops infused with Ringer's solution was observed. These results indicate that the porcine jejunal secretory response to ST and CT does not involve prostaglandins although indomethacin has an influence on the luminal release of PGE2 but not of 5-HT.

Regional differences in neurogenic signal transduction pathway of cholera toxin-induced fluid, electrolyte and serotonin accumulation in the porcine jejunum

Serotonin, acetylcholine and substance P are mediators involved in the secretory response to cholera toxin in the small intestine. The aim of this study was to investigate the regional difference in the effect of a serotonin receptor type 3 antagonist (ondansetron), a nicotinic receptor antagonist (hexamethonium), and a substance P antagonist (the neurokinin receptor type 1 antagonist, CP 99,994) on the cholera toxin-induced fluid accumulation in the porcine jejunum. A dose-range of cholera toxin (0.32-56.00 microg/loop) was instilled for 4 hr in ligated loops in two regions of the proximal jejunum in 6-8-week-old pigs. Ondansetron (200 microg/kg), hexamethonium (10 mg/kg), CP 99,994 (1 mg/kg), or saline alone (control) were given intravenously 10 min. before cholera toxin instillation. Cardiovascular parameters, blood gas data, net fluid accumulation, serotonin and electrolyte concentration in the accumulated fluid were measured. Cardiovascular and blood gas parameters were within the normal range in all treatments. The apparent maximal response in fluid accumulation was reduced 20% in case of ondansetron, and by 33% using CP 99,994 in the aboral region compared to control, whereas no effect was observed in the oral region. Hexamethonium reduced the apparent maximal secretory response in both the oral and aboral regions by 45%. None of the treatments with antagonists changed the luminal content of serotonin or the electrolyte concentrations in the accumulated fluid. The results demonstrate that the involvement of serotonin receptor type 3 and neurokinin type 1 receptors in the transductional pathway of cholera toxin-induced fluid accumulation vary significantly within the jejunum, while the cholinergic (nicotinic) transmission plays an even role.

Capture of human Fab fragments by expanded bed adsorption with a mixed mode adsorbent

A novel group of mixed mode adsorbents has been developed for purification of monoclonal and polyclonal antibodies from a broad range of raw materials such as hybridoma cell culture, ascites fluid, animal sera, milk, whey and egg yolk. The aim of this study was to determine whether such mixed mode adsorbents were also useful for the recovery of recombinant proteins from microbial feedstocks. This paper describes the performance of one of these adsorbents for expanded bed capture of a human Fab fragment from recombinant E. Coli cell extracts. It is concluded that the mixed mode adsorbent binds the Fab fragment efficiently from crude extracts without any requirement for preconditioning the extract by for example de-salting or dilution. The capacity of the mixed mode adsorbent is approx. 12 mg Fab/ml matrix. The novel mixed mode adsorbent can be useful during production of highly purified Fab fragments as the first step in a purification scheme. In this respect the mixed mode adsorbent is advantageous over alternative commercially available ion-exchange materials which require pre-conditioning of cell extract for Fab' capture. Together with the concentration and clarification effect a significant enrichment of the Fab fragment is obtained in one single high yield operation.

Cytokine vaccination: neutralising IL-1alpha autoantibodies induced by immunisation with homologous IL-1alpha

High-affinity IgG autoantibodies (aAb) to IL-1alpha are among the most frequently found aAb to cytokines in humans. To establish an animal model with aAb to IL-1alpha, we immunised mice with recombinant murine IL-1alpha. Unprimed and Bacille Calmette-Guérin (BCG)-primed BALB/cA mice were vaccinated with IL-1alpha coupled to purified protein derivative of tuberculin (PPD). Both unprimed and primed animals developed IgG aAb to IL-1alpha. These aAb persisted at high levels more than 100 days after vaccination and did not cross-react with murine IL-1beta. The induced anti-IL-1alpha aAb inhibited binding of IL-1alpha to the murine T-cell line NOB-1 by simple competition and neutralised IL-1alpha, but not IL-1beta-induced IL-6 in vivo. The aAb did not induce visible discomfort in the animals. In conclusion, long-lasting and high levels of neutralising and specific IgG aAb to IL-1alpha can be induced in mice by vaccination with recombinant murine IL-1alpha conjugated to PPD. Studies of the effects of IL-1alpha aAb in such animals may help clarify the importance of naturally occurring IL-1alpha aAb in humans and permit the evaluation of future therapies with cytokine aAb in patients with immunoinflammatory diseases and cytokine-dependent tumours.

Detection of autoantibodies to cytokines

Autoantibodies to various cytokines have been reported in normal individuals and in patients with various infectious and immunoinflammatory disorders, and similar antibodies (Ab) may be induced in patients receiving human recombinant cytokines. The clinical relevance of these Ab is often difficult to evaluate. Not only are in vitro neutralizing cytokine Ab not necessarily neutralizing in vivo, but assays for binding and neutralizing Ab to cytokines are often difficult to interpret. For example, denaturation of immobilized cytokines in immunoblotting techniques and immunometric assays may leave Ab to the native forms of the mediators unrecognized. On the other hand, Ab may bind nonspecifically and/or with biologically irrelevant low affinities, leading to erroneous interpretations. This article describes in detail the use of radioimmunoassays that we have optimized and used successfully for the detection of high-affinity (auto) Ab to IL-1 alpha, IL-6, GM-CSF, and IFN alpha.

Profile of neurohumoral agents on mesenteric and intestinal blood flow in health and disease

The mesenteric and intestinal blood flow is organized and regulated to support normal intestinal function, and the regulation of blood flow is, in part, determined by intestinal function itself. In the process of the development and adaptation of the intestinal mucosa for the support of the digestive processes and host defense mechanisms, and the muscle layers for propulsion of foodstuffs, a specialized microvascular architecture has evolved in each tissue layer. Compromised mesenteric and intestinal blood flow, which can be common in the elderly, may lead to devastating clinical consequences. This problem, which can be caused by vasospasm at the microvascular level, can cause intestinal ischaemia to any of the layers of the intestinal wall, and can initiate pathological events which promote significant clinical consequences such as diarrhea, abdominal angina and intestinal infarction. The objective of this review is to provide the reader with some general concepts of the mechanisms by which neurohumoral vasoactive substances influence mesenteric and intestinal arterial blood flow in health and disease with focus on transmural transport processes (absorption and secretion). The complex regulatory mechanisms of extrinsic (sympathetic-parasympathetic and endocrine) and intrinsic (enteric nervous system and humoral endocrine) components are presented. More extensive reviews of platelet function, atherosclerosis, hypertension, diabetes mellitus, the carcinoid syndrome, 5-hydroxytryptamine and nitric oxide regulation of vascular tone are presented in this context. The possible options of pharmacological intervention (e.g. vasodilator agonists and vasoconstrictor antagonists) used for the treatment of abnormal mesenteric and intestinal vascular states are also discussed.

Functional characterisation of tachykinin receptors mediating ion transport in porcine jejunum

In the present study, tachykinin receptors (designated NK 1, NK2 and NK3) involved in regulation of ion transport in porcine jejunum were characterised. Stripped tissue preparations were mounted in Ussing chambers and short-circuited. Substance P produced a concentration dependent increase in short-circuit current, the relationship showing a double sigmoidal form. The non-peptide NK1 receptor antagonist, CP 99,994 ((2S,3S)-3-(2-methoxybenzyl)amino-2-phenylpiperidine), caused a dextral shift of the first sigmoidal response, indicating the involvement of an NK1 receptor. This was further supported by a concentration-dependent response of the NK1 receptor agonist [Sar9Met(O2)11]substance P with an EC50 value of 235.0+/-53.9 nM. Increasing concentrations of CP 99,994 (0.1, 0.3 and 1 microM) produced a parallel dextral shift of the [Sar9Met(O2)11]substance P curve with a slope of the Schild regression significantly different from unity (1.59). The neurokinin A concentration-response curve, with an EC50 value of 68.87+/-16.23 nM, was not significantly changed by the non-peptide NK2 receptor antagonist SR 48,968 ((S)-N-methyl-N-(4-(4-acetylamino-4-phenylpiperidino)-2-(3,4-dichlorophe nyl)butyl)bezamide). In additional studies, the peptide NK2 receptor antagonists, GR 94,800 (PhCO-Ala-Ala-DTrp-Phe-DPro-Pro-NleNH2) and PD 147,714 ((2,3-diOMeZ)-(S)Trp(S)alphaMePheGlyNH2), did not change the response to neurokinin A. However, CP 99,994 totally inhibited neurokinin A responses at 0.5 microM and above. The NK2 receptor agonist, [beta-Ala8]neurokinin A-(4-10), caused only an increase in short-circuit current in microM concentrations, whereas the NK3 receptor agonist, senktide, did not elicit a response. These results indicate, that substance P and neurokinin A mediate ion transport in porcine jejunum through NK1 receptors. However, tachykinins seem to activate another receptor. Two active conformers of the NK1 receptor might be present.

Regional differences in the effect of cholera toxin and enterotoxigenic Escherichia coli infection on electrolyte and fluid transport in the porcine small intestine

The regional differences in secretory and absorptive responses to cholera toxin (CT) and to infection by enterotoxigenic Escherichia coli (ETEC), producing heat-stable enterotoxins, were studied in the porcine small intestine. Proximal, mid and distal small intestine from newly weaned piglets were used. Na+ and Cl- fluxes and electrical parameters in CT-stimulated and ETEC-infected intestine were measured by the Ussing chamber technique. In addition, CT-induced fluid accumulation in ligated loops was measured. CT induced fluid accumulation, which was highest in the proximal segment and decreased in the aboral direction of the small intestine. In addition, CT induced a net Cl- secretion in the proximal and mid segments, while net Na+ absorption was reduced only in the proximal segment. The ETEC-infected intestine showed a net increase in Cl- secretion in the proximal part and abolished the net Na+ absorption in the distal segment. These results demonstrate segmental differences in the epithelial transport responses to enterotoxin from Vibrio cholerae and to ETEC infection. This needs to be taken into consideration in relation to oral rehydration studies.

Secretory response to cholera toxin in the porcine jejunum under different types of general anaesthesia

Investigations of intestinal secretion are often performed under anaesthesia. This study evaluates the influence of anaesthetic agents on the intestinal secretion induced by cholera toxin (CT) in the pig. CT was instilled for 4 h in ligated jejunal loops under anaesthesia with halothane, saffan, alpha-chloralose, or propofol. Cardiovascular parameters, blood gas data, plasma cortisol levels, net fluid accumulation, intraluminal mediators (serotonin (5-HT), prostaglandin E2 (PGE2)) and electrolyte concentrations in the accumulated fluid were determined. The systolic blood pressure and heart rate was highest for saffan-anaesthetized pigs (blood pressure: saffan > alpha-chloralose > propofol = halothane; heart rate: saffan > alpha-chloralose = propofol = halothane), while blood gases and cortisol levels were within the same range. CT induced a dose-dependent fluid accumulation under all four anaesthetics. The fluid accumulation was significantly higher in pigs treated with saffan, alpha-chloralose and propofol than in halothane-treated pigs (saffan = alpha-chloralose > propofol > halothane). There was no significant difference in electrolyte concentrations in the accumulated fluid or in the luminal content of 5-HT and PGE2 between anaesthetics. The results demonstrate that anaesthetic agents profoundly influence the secretory response in the small intestine and indicate the importance of the choice of anaesthetic in this type of experiment.

Antibody to granulocyte-macrophage colony-stimulating factor is a dominant anti-cytokine activity in human IgG preparations

Pharmaceutical preparations of normal human immunoglobulin (IgG) are known to contain high-avidity and neutralizing antibodies (Ab) to the cytokines interleukin (IL)-1alpha, IL-6, and interferon (IFN)alpha. To test for other cytokine Ab, 23 batches of IgG were tested for saturable binding to eight 125I-labeled recombinant cytokines. All batches bound granulocyte-macrophage colony-stimulating factor (GM-CSF) with high avidity (Kav approximately 10 pmol/L) and capacities of up to 5 mumol GM-CSF/mol IgG. Only 1 of 15 batches bound IL-5, also with high avidity, whereas 13 of 15 batches bound to IL-10 but with lower capacities and avidities. None of the IgG preparations bound IL-1 receptor antagonist (IL-1ra), IL-2, IL-3, IL-4, or G-CSF. Cross-binding and absorption analyses revealed identical or slightly stronger binding of recombinant GM-CSF, IL-5, and IL-10 than their native counterparts. GM-CSF-IgG complexes did not bind to cellular GM-CSF receptors, but Fc-dependent binding occurred to blood polymorphonuclear cells. Increased binding of GM-CSF to patient sera correlated positively with the binding capacities of infused IgG preparations. Patient and normal sera did not interfere with the binding of Ab to GM-CSF. From these and previous experiments, we conclude that pools of normal human IgG contain variable amounts of specific and high-avidity Ab to some cytokines, and that Ab to GM-CSF constitute a dominant anti-cytokine activity in these preparations. These Ab are available for reaction in vivo following IgG therapy.

Somatostatin attenuates the hyperthermia induced increase in neutrophil concentration

This study was designed to test the hypothesis that the immune changes seen during in vivo whole body hyperthermia are mediated by elevations in the plasma concentrations of either catecholamines, growth hormone or beta-endorphins. Eight healthy volunteers were immersed in a hot water bath (WI; water temperature 39.5 degrees C) for 2 h during which their rectal temperature rose to 39.5 degrees C. In a single blind, randomized, cross-over study the stress hormone effects were blocked one at a time by administration of propranolol, somatostatin or naloxone; the results were compared to those obtained during saline infusion (control). Blood samples were collected before, at the end of 2 h of WI (body temperature 39.5 degrees C), and 2 h later. Hormone blockade did not abolish the hyperthermia-induced recruitment of natural killer (NK) cells to the blood, and no influence was observed on the percentages or concentrations of any other subpopulations of blood mononuclear cells, except that the number of cluster designation (CD)3+ cells slightly increased after hyperthermia only in the propranolol experiment. Furthermore, the NK cell activity, both unstimulated and interferon-alpha or interleukin-2 stimulated, did not differ from the control situation. It is of interest, however, that somatostatin partly abolished the hyperthermia induced increase in the neutrophil number. Based on these data and previous results showing that growth hormone infusion increases the concentration of neutrophils in the blood, it is suggested that growth hormone is at least partly responsible for hyperthermia induced neutrocytosis.

Secretory pathways in Salmonella Typhimurium-induced fluid accumulation in the porcine small intestine

The involvement of 5-hydroxytryptamine (5-HT) and 5-HT3 receptors and prostaglandin E2 (PGE2) in Salmonella Typhimurium-induced fluid accumulation in the porcine small intestine was investigated. Salmonella Typhimurium (10(8) and 10(10) cfu) and cholera toxin (CT; 20 microg) were instilled for 8 and 11 h in ligated loops in the porcine jejunum and ileum. Fluid accumulation and concentrations of Na+, K+, Cl-, 5-HT and PGE2 in the fluid accumulated in the loops were measured. The fluid accumulation was also measured when Salmonella Typhimurium (10(10) cfu) and CT (20 microg) were instilled for 8 h in ligated loops in jejunum and ileum in pigs given subcutaneous injections of saline or the 5-HT3 receptor antagonist ondansetron (200 microg/kg). Salmonella Typhimurium (10(10) cfu) and CT both induced fluid accumulation in jejunum and ileum after 8 and 11 h. Both treatments also induced an increase in luminal release of 5-HT and PGE2. The accumulated fluid was iso-osmotic and hyperosmotic in CT- and Salmonella Typhimurium-treated loops, respectively. Ondansetron reduced the Typhimurium-induced fluid accumulation in both jejunum and ileum by c. 40%, while it failed to reduce the response to CT. These results demonstrate that 5-HT and PGE2 are released and 5-HT3 receptors activated in the secretory pathway of Typhimurium in the porcine small intestine.

Signal transduction pathways for serotonin as an intestinal secretagogue

This review presents a signal transduction pathways for serotonin (5-hydroxytryptamine, 5-HT) as an intestinal secretagogue and some recently published related findings. 5-HT is a secretagogue in the small and large intestine of all studied species including pig and man. 5-HT mediates intestinal secretion through activation of at least the epithelial 5-HT2, and neuronal 5-HT3, and 5-HT4 receptors in the submucosal plexus, including a reflex arc. 5-HT activates both a cholinergic and a non-cholinergic pathway in its secretory response. Intracellular mediators include at least eicosanoids (prostaglandin E2), calcium, phosphoinositols (1,4,5-inositol trisphosphate) and maybe nitric oxide and cyclic nucleotides. Pig small intestine appears to be an appropriate model for the human small intestine with respect to the signal transduction pathways for 5-HT as an intestinal secretagogue. Species and segmental differences in the signal transduction pathways for 5-HT as an intestinal secretagogues are discussed together with related news on 5-HT receptors, 5-HT antagonists in clinical use, the enteric nervous system, and intracellular mediators.

The effect of alpha-trinositol on cholera toxin-induced fluid accumulation in pig (Sus scrofa domesticus) jejunum in vivo

The effect of alpha-trinositol (D-myo-inositol-1,2,6-trisphosphate) on cholera toxin-induced fluid accumulation (i.e., net fluid secretion) was studied in the pig jejunum in vivo. Cholera toxin caused a dose-dependent fluid accumulation in control experiments. Intravenous injection of alpha-trinositol produced a reduction of the response to cholera toxin with a significant maximal inhibition of 36%. However, in high concentrations of alpha-trinositol this inhibition was absent.

Induction of interleukin-6 (IL-6) autoantibodies through vaccination with an engineered IL-6 receptor antagonist

Neutralization of cytokine activity by monoclonal antibodies or receptor antagonists is beneficial in the treatment of immune and neoplastic diseases, but the necessity for continuous parenteral delivery of these anticytokine agents poses considerable practical limitations. A viable alternative is to induce a neutralizing antibody response. Using transgenic mice with high circulating levels of human interleukin-6 (hIL-6), we show that injection of the hIL-6 receptor antagonist Sant1 (an IL-6 variant with seven amino-acid substitutions) induces a strong anti-hIL-6 antibody response. The elicited antibodies bind circulating hIL-6 with very high affinity, totally masking it, and neutralize hIL-6 bioactivity both in vitro and in vivo.

Effect of ondansetron on Salmonella typhimurium-induced net fluid accumulation in the pig jejunum in vivo

Two major pathophysiological mechanisms explaining the diarrhoea induced by Salmonella typhimurium have been suggested to be: (a) invasion of the intestine by the bacteria, and (b) an enterotoxin resembling Vibrio cholerae toxin. Cholera toxin is a potent secretagogue in pig small intestine and induces secretion partly by activating 5-hydroxytryptamine receptors, following release of 5-hydroxytryptamine. Ondansetron is a selective 5-hydroxytryptamine-3 receptor antagonist, which reduces the cholera toxin-evoked fluid accumulation in pig jejunum. The aim of this study was to investigate the effect of ondansetron on Salmonella typhimurium-induced fluid accumulation in ligated loops of pig jejunum in vivo. 10(10) colony-forming units of the bacteria was injected into loops and incubated for 8 hr. 200 mg x kg-1 ondansetron given subcutaneously reduced the Salmonella typhimurium-induced fluid accumulation by about 40%. This results suggests the involvement of 5-hydroxytryptamine and 5-hydroxytryptamine-3 receptors in Salmonella typhimurium-induced diarrhoea.