CycleGAN-Based Image to Image Translation for Realistic Surgical Training Phantoms

Training in surgery is essential for surgeons to develop skill and dexterity. Physical training phantoms provide excellent haptic feedback and tissue properties for stitching and operating with authentic instruments and are easily available. However, they lack realistic traits and fail to reflect the complex environment of a surgical scene. Generative Adversarial Networks can be used for image-to-image translation, addressing the lack of realism in physical phantoms, by mapping patterns from the intraoperative domain onto the video stream captured during training with these surgical simulators. This work aims to achieve a successful I2I translation, from intra-operatory mitral valve surgery images onto a surgical simulator, using the CycleGAN model. Different experiments are performed - comparing the Mean Square Error Loss with the Binary Cross Entropy Loss; validating the Fréchet Inception Distance as a training and image quality metric; and studying the impact of input variability on the model performance. Differences between MSE and BCE are modest, with MSE being marginally more robust. The FID score proves to be very useful in identifying the best training epochs for the CycleGAN I2I translation architecture. Carefully selecting the input images can have a great impact in the end results. Using less style variability and input images with good feature details and clearly defined characteristics enables the network to achieve better results.Clinical Relevance- This work further contributes for the domain of realistic surgical training, successfully generating fake intra operatory images from a surgical simulator of the cardiac mitral valve.

A vaccine targeting resistant tumours by dual T cell plus NK cell attack

Most cancer vaccines target peptide antigens, necessitating personalization owing to the vast inter-individual diversity in major histocompatibility complex (MHC) molecules that present peptides to T cells. Furthermore, tumours frequently escape T cell-mediated immunity through mechanisms that interfere with peptide presentation¹. Here we report a cancer vaccine that induces a coordinated attack by diverse T cell and natural killer (NK) cell populations. The vaccine targets the MICA and MICB (MICA/B) stress proteins expressed by many human cancers as a result of DNA damage². MICA/B serve as ligands for the activating NKG2D receptor on T cells and NK cells, but tumours evade immune recognition by proteolytic MICA/B cleavage^3,4. Vaccine-induced antibodies increase the density of MICA/B proteins on the surface of tumour cells by inhibiting proteolytic shedding, enhance presentation of tumour antigens by dendritic cells to T cells and augment the cytotoxic function of NK cells. Notably, this vaccine maintains efficacy against MHC class I-deficient tumours resistant to cytotoxic T cells through the coordinated action of NK cells and CD4⁺ T cells. The vaccine is also efficacious in a clinically important setting: immunization following surgical removal of primary, highly metastatic tumours inhibits the later outgrowth of metastases. This vaccine design enables protective immunity even against tumours with common escape mutations.

Self-reactive T cells induce and perpetuate chronic relapsing arthritis

BACKGROUND

CD4⁺ T cells play a central role during the early stages of rheumatoid arthritis (RA), but to which extent they are required for the perpetuation of the disease is still not fully understood. The aim of the current study was to obtain conclusive evidence that T cells drive chronic relapsing arthritis.

METHODS

We used the rat pristane-induced arthritis model, which accurately portrays the chronic relapsing-remitting disease course of RA, to examine the contribution of T cells to chronic arthritis.

RESULTS

Rats subjected to whole-body irradiation and injected with CD4⁺ T cells from lymph nodes of pristane-injected donors developed chronic arthritis that lasted for more than 4 months, whereas T cells from the spleen only induced acute disease. Thymectomy in combination with irradiation enhanced the severity of arthritis, suggesting that sustained lymphopenia promotes T cell-driven chronic inflammation in this model. The ability of T cells to induce chronic arthritis correlated with their expression of Th17-associated transcripts, and while depletion of T cells in rats with chronic PIA led to transient, albeit significant, reduction in disease, neutralization of IL-17 resulted in almost complete and sustained remission.

CONCLUSION

These findings show that, once activated, self-reactive T cells can sustain inflammatory responses for extended periods of time and suggest that such responses are promoted in the presence of IL-17.

The role of MHC class II polymorphisms for DM-mediated peptide editing and autoimmunity

Polymorphisms in MHC class II (MHCII) genes are the strongest risk factors for the development of autoimmune diseases, such as type I diabetes (T1D). T1D is associated with allelic variants of the MHCII molecule HLA-DQ. In the nonobese diabetic (NOD) mouse, the orthologous molecule, I-Ag7, also predisposes mice to spontaneous diabetes development. To investigate the functional impact of natural MHCII polymorphisms on DM binding and T1D we introduced selected mutations in the genome of the NOD mouse by CRISPR/Cas9 genomic editing.

Our approach was to first identify unique polymorphisms in the putative interface of I-Ag7, and then assess the impact of these polymorphisms on DM-mediated peptide editing in vitro. Several polymorphisms increased the interaction between I-Ag7 and DM and augmented peptide binding. The substitution of lysine (K) 40 in I-Aα with glutamic acid (E) had the strongest effect on DM editing and accelerated peptide binding more than 9-fold. Lysine at position α40 is unique to the diabetes associated I-Ag7 molecule and was therefore selected for in vivo evaluation. Homozygous and heterozygous K40E mutant mice showed increased H2-DM protein expression compared to WT littermate controls. Increased H2-DM levels were accompanied by an increase in intra- and extracellular I-Ag7 expression. This suggests that the K40E mutation promotes the interaction between H2-DM and I-Ag7, and likely, represents increased intracellular dimerization and more stable I-Ag7/peptide complexes on the cell surface. Currently, we are evaluating whether increased editing of the MHCII peptide repertoire mediated by the K40E mutation influences spontaneous diabetes development.

MHC class II alleles associated with Th1 rather than Th17 type immunity drive the onset of early arthritis in a rat model of rheumatoid arthritis

Polymorphisms in the MHC class II (MHCII) genes are strongly associated with rheumatoid arthritis, supporting the importance of autoreactive T helper (Th) cells for the development of this disease. Here, we used pristane-induced arthritis (PIA), induced by the non-antigenic hydrocarbon pristane, to study the impact of different MHCII alleles on T-cell activation and differentiation. In MHCII-congenic rats with disease-promoting MHCII alleles, pristane primarily induced activation of Th1 cells, whereas activated T cells were Th17 biased in rats with protective MHCII alleles. Neutralization of IFN-γ during T-cell activation abrogated the development of disease, suggesting that Th1 immunity is important for disease induction. Neutralization of IL-17, by contrast, suppressed arthritis only when performed in rats with established disease. Adoptive T-cell transfers showed that T cells acquired arthritogenic capacity earlier in strains with a prevailing Th1 response. Moreover, upon pristane injection, these strains exhibited more Ag-primed OX40+ and proliferating T cells of polyclonal origin. These data show that T cells are polarized upon the first encounter with peptide-MHCII complexes in an allele-dependent fashion. In PIA, the polyclonal expansion of autoreactive Th1 cells was necessary for the onset of arthritis, while IL-17 mediated immunity contributed to the progression to chronic disease.

Approach for Identifying Human Leukocyte Antigen (HLA)-DR Bound Peptides from Scarce Clinical Samples

Immune-mediated diseases strongly associating with human leukocyte antigen (HLA) alleles are likely linked to specific antigens. These antigens are presented to T cells in the form of peptides bound to HLA molecules on antigen presenting cells, e.g. dendritic cells, macrophages or B cells. The identification of HLA-DR-bound peptides presents a valuable tool to investigate the human immunopeptidome. The lung is likely a key player in the activation of potentially auto-aggressive T cells prior to entering target tissues and inducing autoimmune disease. This makes the lung of exceptional interest and presents an ideal paradigm to study the human immunopeptidome and to identify antigenic peptides.Our previous investigation of HLA-DR peptide presentation in the lung required high numbers of cells (800 × 10(6) bronchoalveolar lavage (BAL) cells). Because BAL from healthy nonsmokers typically contains 10-15 × 10(6) cells, there is a need for a highly sensitive approach to study immunopeptides in the lungs of individual patients and controls.In this work, we analyzed the HLA-DR immunopeptidome in the lung by an optimized methodology to identify HLA-DR-bound peptides from low cell numbers. We used an Epstein-Barr Virus (EBV) immortalized B cell line and bronchoalveolar lavage (BAL) cells obtained from patients with sarcoidosis, an inflammatory T cell driven disease mainly occurring in the lung. Specifically, membrane complexes were isolated prior to immunoprecipitation, eluted peptides were identified by nanoLC-MS/MS and processed using the in-house developed ClusterMHCII software. With the optimized procedure we were able to identify peptides from 10 × 10(6) cells, which on average correspond to 10.9 peptides/million cells in EBV-B cells and 9.4 peptides/million cells in BAL cells. This work presents an optimized approach designed to identify HLA-DR-bound peptides from low numbers of cells, enabling the investigation of the BAL immunopeptidome from individual patients and healthy controls in order to identify disease-associated peptides.

Positional identification of RT1-B (HLA-DQ) as susceptibility locus for autoimmune arthritis

Rheumatoid arthritis (RA) is associated with amino acid variants in multiple MHC molecules. The association to MHC class II (MHC-II) has been studied in several animal models of RA. In most cases these models depend on T cells restricted to a single immunodominant peptide of the immunizing Ag, which does not resemble the autoreactive T cells in RA. An exception is pristane-induced arthritis (PIA) in the rat where polyclonal T cells induce chronic arthritis after being primed against endogenous Ags. In this study, we used a mixed genetic and functional approach to show that RT1-Ba and RT1-Bb (RT1-B locus), the rat orthologs of HLA-DQA and HLA-DQB, determine the onset and severity of PIA. We isolated a 0.2-Mb interval within the MHC-II locus of three MHC-congenic strains, of which two were protected from severe PIA. Comparison of sequence and expression variation, as well as in vivo blocking of RT1-B and RT1-D (HLA-DR), showed that arthritis in these strains is regulated by coding polymorphisms in the RT1-B genes. Motif prediction based on MHC-II eluted peptides and structural homology modeling suggested that variants in the RT1-B P1 pocket, which likely affect the editing capacity by RT1-DM, are important for the development of PIA.

Hydroxyethylene isosteres introduced in type II collagen fragments substantially alter the structure and dynamics of class II MHC Aq/glycopeptide complexes

Introduction of hydroxyethylene isosteres into glycopeptides led to loss of Aq affinity and subsequent T cell response due to disruption of hydrogen bond networks.

Review article: Associations between Helicobacter pylori and obesity--an ecological study

BACKGROUND

There is emerging debate over the effect of Helicobacter pylori infection on body mass index (BMI). A recent study demonstrated that individuals who underwent H. pylori eradication developed significant weight gain as compared to subjects with untreated H. pylori colonisation.

AIM

To elucidate the association between H. pylori colonisation and the prevalence of overweight and obesity in developed countries.

METHODS

The literature was searched for publications reporting data on H. pylori prevalence rates and obesity prevalence rates. Studies selected reported H. pylori prevalence in random population samples with sample sizes of more than 100 subjects in developed countries (GDP >25,000 US$/person/year). Corresponding BMI distributions for corresponding countries and regions were identified. Nonparametric tests were used to compare the association between H. pylori and overweight and obesity rates.

RESULTS

Forty-nine studies with data from 10 European countries, Japan, the US and Australia were identified. The mean H. pylori rate was 44.1% (range 17-75%), the mean rates for obesity and overweight were 46.6 (± 16)% and 14.2 (± 8.9)%. The rate of obesity and overweight were inversely and significantly (r = 0.29, P < 0.001) correlated with the prevalence of H. pylori infection.

CONCLUSIONS

There is an inverse correlation between H. pylori prevalence and rate of overweight/obesity in countries of the developed world. Thus, the gradual decrease of the H. pylori colonisation that has been observed in recent decades (or factors associated with decrease of) could be causally related to the obesity endemic observed in the Western world.

Natural polymorphisms in Tap2 influence negative selection and CD4∶CD8 lineage commitment in the rat

Genetic variation in the major histocompatibility complex (MHC) affects CD4∶CD8 lineage commitment and MHC expression. However, the contribution of specific genes in this gene-dense region has not yet been resolved. Nor has it been established whether the same genes regulate MHC expression and T cell selection. Here, we assessed the impact of natural genetic variation on MHC expression and CD4∶CD8 lineage commitment using two genetic models in the rat. First, we mapped Quantitative Trait Loci (QTLs) associated with variation in MHC class I and II protein expression and the CD4∶CD8 T cell ratio in outbred Heterogeneous Stock rats. We identified 10 QTLs across the genome and found that QTLs for the individual traits colocalized within a region spanning the MHC. To identify the genes underlying these overlapping QTLs, we generated a large panel of MHC-recombinant congenic strains, and refined the QTLs to two adjacent intervals of ∼0.25 Mb in the MHC-I and II regions, respectively. An interaction between these intervals affected MHC class I expression as well as negative selection and lineage commitment of CD8 single-positive (SP) thymocytes. We mapped this effect to the transporter associated with antigen processing 2 (Tap2) in the MHC-II region and the classical MHC class I gene(s) (RT1-A) in the MHC-I region. This interaction was revealed by a recombination between RT1-A and Tap2, which occurred in 0.2% of the rats. Variants of Tap2 have previously been shown to influence the antigenicity of MHC class I molecules by altering the MHC class I ligandome. Our results show that a restricted peptide repertoire on MHC class I molecules leads to reduced negative selection of CD8SP cells. To our knowledge, this is the first study showing how a recombination between natural alleles of genes in the MHC influences lineage commitment of T cells.

Peptides from degraded cytoplasmic proteins are transported via TAP into the endoplasmic reticulum for loading onto MHC class I molecules. TAP is encoded by Tap1 and Tap2, which in rodents are located close to the MHC class I genes. In the rat, genetic variation in Tap2 gives rise to two different transporters: a promiscuous A variant (TAP-A) and a more restrictive B variant (TAP-B). It has been proposed that the class I molecule in the DA rat (RT1-A^a) has co-evolved with TAP-A and it has been shown that RT1-A^a antigenicity is changed when co-expressed with TAP-B. To study the contribution of different allelic combinations of RT1-A and Tap2 to the variation in MHC expression and T cell selection, we generated DA rats with either congenic or background alleles in the RT1-A and Tap2 loci. We found increased numbers of mature CD8SP cells in the thymus of rats which co-expressed RT1-A^a and TAP-B. This increase of CD8 cells could be explained by reduced negative selection, but did not correlate with RT1-A^a expression levels on thymic antigen presenting cells. Thus, our results identify a crucial role of the TAP and the quality of the MHC class I repertoire in regulating T cell selection.

C57BL/6 mice need MHC class II Aq to develop collagen-induced arthritis dependent on autoreactive T cells

INTRODUCTION

Collagen-induced arthritis (CIA) has traditionally been performed in MHC class II A(q)-expressing mice, whereas most genetically modified mice are on the C57BL/6 background (expressing the b haplotype of the major histocompatibility complex (MHC) class II region). However, C57BL/6 mice develop arthritis after immunisation with chicken-derived collagen type II (CII), but arthritis susceptibility has been variable, and the immune specificity has not been clarified.

OBJECTIVE

To establish a CIA model on the C57BL/6 background with a more predictable and defined immune response to CII.

RESULTS

Both chicken and rat CII were arthritogenic in C57BL/6 mice provided they were introduced with high doses of Mycobacterium tuberculosis adjuvant. However, contaminating pepsin was strongly immunogenic and was essential for arthritis development. H-2(b)-restricted T cell epitopes on chicken or rat CII could not be identified, but expression of A(q) on the C57BL/6 background induced T cell response to the CII260-270 epitope, and also prolonged the arthritis to be more chronic.

CONCLUSIONS

The putative (auto)antigen and its arthritogenic determinants in C57BL/6 mice remains undisclosed, questioning the value of the model for addressing T cell-driven pathological pathways in arthritis. To circumvent this impediment, we recommend MHC class II congenic C57BL/6N.Q mice, expressing A(q), with which T cell determinants have been thoroughly characterised.

(E)-alkene and ethylene isosteres substantially alter the hydrogen-bonding network in class II MHC A(q)/glycopeptide complexes and affect T-cell recognition

The structural basis for antigen presentation by class II major histocompatibility complex (MHC) proteins to CD4(+) T-cells is important for understanding and possibly treating autoimmune diseases. In the work described in this paper, (E)-alkene and ethylene amide-bond isosteres were used to investigate the effect of removing hydrogen-bonding possibilities from the CII259-270 glycopeptide, which is bound by the arthritis-associated murine A(q) class II MHC protein. The isostere-modified glycopeptides showed varying and unexpectedly large losses of A(q) binding that could be linked to the dynamics of the system. Molecular dynamics (MD) simulations revealed that the backbone of CII259-270 and the A(q) protein are able to form up to 11 hydrogen bonds, but fewer than this number are present at any one time. Most of the strong hydrogen-bond interactions were formed by the N-terminal part of the glycopeptide, i.e., in the region where the isosteric replacements were made. The structural dynamics also revealed that hydrogen bonds were strongly coupled to each other; the loss of one hydrogen-bond interaction had a profound effect on the entire hydrogen-bonding network. The A(q) binding data revealed that an ethylene isostere glycopeptide unexpectedly bound more strongly to A(q) than the corresponding (E)-alkene, which is in contrast to the trend observed for the other isosteres. Analysis of the MD trajectories revealed that the complex conformation of this ethylene isostere was structurally different and had an altered molecular interaction pattern compared to the other A(q)/glycopeptide complexes. The introduced amide-bond isosteres also affected the interactions of the glycopeptide/A(q) complexes with T-cell receptors. The dynamic variation of the patterns and strengths of the hydrogen-bond interactions in the class II MHC system is of critical importance for the class II MHC/peptide/TCR signaling system.

A 13-nation population survey of upper gastrointestinal symptoms: prevalence of symptoms and socioeconomic factors

BACKGROUND

Previous data collected in separate studies using various different survey instruments have suggested some variability in the prevalence of symptoms between nations. However, there is a lack of studies which assess and compare the prevalence of upper gastrointestinal symptoms contemporaneously in various countries using a uniform, standardised method.

AIM

To determine the prevalence of upper gastrointestinal (UGI) symptoms in 13 European countries, and the association between socioeconomic factors and symptoms using a standardised method.

METHODS

A representative age- and gender-stratified sample of 23,163 subjects (aged 18-69 years) was surveyed.

RESULTS

The prevalence of UGI symptoms was 38%. UGI symptoms were most prevalent in Hungary [45%, 95% confidence interval (CI): 42.2-48.4] and lowest in the Netherlands (24%, 95% CI: 21.0-26.2). UGI symptoms were more prevalent in women (39%, 95% CI: 38.4-39.6) vs. men (37%, 95% CI: 36.4-37.6). Heartburn (24%, 95% CI: 23.4-24.6) and acidic reflux (14%, 95% CI: 13.6-14.4) were most common. With age, the prevalence of UGI symptoms decreased (e.g. 18-29 years: 43%, 95% CI: 41.4-44.3 vs. 50-69 years: 33%, 95% CI: 32.3-34.4); in contrast, the frequency of symptom episodes/year increased with age (e.g. 18-29 years: 11.3 episodes per years, 95% CI: 10.5-12.1 vs. 50-69 years: 21.8, 95% CI: 20.7-22.9). Socioeconomic status as measured by gross domestic product was inversely associated with symptoms and in total, socioeconomic factors, gender, body mass index, smoking habits and alcohol consumption explained 83% of the variance of UGI symptoms.

CONCLUSIONS

There are marked differences in the country specific prevalence of upper gastrointestinal complaints. Socioeconomic factors are closely associated with the prevalence of upper gastrointestinal symptoms.

Is there any association between disturbed gastrointestinal visceromotor and sensory function and impaired quality of life in functional dyspepsia?

BACKGROUND Functional dyspepsia (FD) is now categorized into the epigastric pain syndrome (EPS) and the postprandial distress syndrome (PDS). However, the role of disturbed gastric emptying and sensory function for the reduction of health-related quality of life (HRQOL) has not yet been studied in EPS and PDS. METHODS A total of 300 refractory FD patients and 450 healthy blood donors (BD) were studied. BD were stratified in subjects with (BD+) and without (BD-) concomitant FD symptoms. Gastric motor and sensory function, generic and disease-specific HRQOL [physical (PCS) and mental component summary (MCS)] and affective disorders were assessed. Twenty randomly selected BD-, 50 BD+ (36 PDS, 72%), and 110 FD (95 PDS, 86.4%) patients had additional function testing. KEY RESULTS Health-related quality of life was significantly reduced in FD patients (PCS = 40.7 +/- 8.8, MCS = 39.7 +/- 11.3, both P < 0.0001) compared to BD+ (PCS = 52.0 +/- 7.6, MCS = 49.0 +/- 9.4) and BD- (PCS = 56.0 +/- 4.3, MCS = 52.8 +/- 7.2). GET (t((1/2)), min) was significantly (both P < 0.0001) longer in FD patients (143.0 +/- 7.3) compared to BD+ (101.1 +/- 6.3) and BD- (73.8 +/- 7.6). FD patients scored significantly higher for 'pain' (P < 0.0001) and 'nausea' (P = 0.023), there was no difference for 'fullness' compared to BD. Impairment of GET was not associated with HRQOL. In FD patients, an augmented symptom response to the test meal (fullness, nausea) was associated with MCS, there was no difference between FD patients with EPS or PDS. CONCLUSIONS & INFERENCES In EPS and PDS, delayed gastric empting and altered sensory function are disease markers but not directly linked to the severity of HRQOL impairment or clinical presentation of FD.

Naturally presented peptides on major histocompatibility complex I and II molecules eluted from central nervous system of multiple sclerosis patients

Tandem mass spectrometry was used to identify naturally processed peptides bound to major histocompatibility complex (MHC) I and MHC II molecules in central nervous system (CNS) of eight patients with multiple sclerosis (MS). MHC molecules were purified from autopsy CNS material by immunoaffinity chromatography with monoclonal antibody directed against HLA-A, -B, -C, and -DR. Subsequently peptides were separated by reversed-phase HPLC and analyzed by mass spectrometry. Database searches revealed 118 amino acid sequences from self-proteins eluted from MHC I molecules and 191 from MHC II molecules, corresponding to 174 identified source proteins. These sequences define previously known and potentially novel autoantigens in MS possibly involved in disease induction and antigen spreading. Taken together, we have initiated the characterization of the CNS-expressed MHC ligandome in CNS diseases and were able to demonstrate the presentation of naturally processed myelin basic protein peptides in the brain of MS patients.

Role of Epac1 in mediating anti-proliferative effects of prostanoid EP(2) receptors and cAMP in human lung fibroblasts

In lung fibroblasts, proliferation is inhibited by activation of EP(2) prostanoid receptors which are known to couple to adenylyl cyclase. Beside the classic target of cAMP, protein kinase A (PKA), alternative cAMP effectors have been identified, among them Epac (exchange protein activated by cAMP). The present study aimed to illuminate transduction pathways mediating the anti-proliferative effects of EP(2) receptors in lung fibroblasts. Proliferative activity of human lung fibroblasts was determined by measuring [(3)H]-thymidine incorporation. The selective EP(2) receptor agonist butaprost inhibited [(3)H]-thymidine incorporation by 75%, an effect mimicked by forskolin, the phosphodiesterase inhibitor IBMX, the stable cAMP analogues dibutyryl-cAMP and bromo-cAMP, as well as by the Epac selective cAMP analogues 8-pCPT-2'-O-Me-cAMP and Sp-8-pCPT-2'-O-Me-cAMPS, whereas the PKA selective agonist 6-Bnz-cAMP was inactive. The PKA inhibitor Rp-8-Br-cAMPS inhibited butaprost-induced phosphorylation of CREB (cAMP response element-binding protein), but did not affect butaprost-induced inhibition of [(3)H]-thymidine incorporation. Partial knockdown of Epac1 by specific siRNA transfection resulted in a marked attenuation of the inhibitory potency of butaprost, whereas transfection of Epac2 siRNA or non-silencing siRNA did not affect the effectiveness of butaprost to inhibit [(3)H]-thymidine incorporation. In conclusion, Epac1 rather than the classic cAMP effector PKA is a crucial element in the signal transduction pathway mediating anti-proliferative effects of EP(2) receptor activation.

Muscarinic receptors mediate stimulation of collagen synthesis in human lung fibroblasts

Clinical observations indicate that in chronic obstructive pulmonary disease patients, the long-acting muscarinic antagonist tiotropium delays decline in airway function, suggesting that cholinergic mechanisms contribute to long-term structural changes. Human lung fibroblasts express muscarinic receptors and the present study aimed to explore their role in controlling collagen synthesis. MRC-5, HEL-299 and primary human lung fibroblasts (phLFb) were cultured. Incorporation of [(3)H]-proline into cellular proteins was determined as measure of collagen synthesis. In MRC-5 cells, the muscarinic agonist carbachol enhanced [(3)H]-proline incorporation in a concentration-dependent manner (effective concentration of 50%: 220 nM, increase at 10 microM by 40-55%, in a different series of experiments). Likewise, 10 microM oxotremorine caused an increase of approximately 65%. For comparison, transforming growth factor-beta1 (5 ng x mL(-1)) caused an increase of approximately 80%. Effects of carbachol on total [(3)H]-proline incorporation and collagenase-sensitive [(3)H]-proline fraction were similar. The effect of 10 microM carbachol was inhibited by tiotropium (inhibitory concentration of 50%: 110 pM), prevented by pertussis toxin and the mitogen-activated protein kinase inhibitor, PD 98059. Muscarinic agonists also enhanced [(3)H]-proline incorporation in a tiotropium-sensitive manner in HEL-299 cells and phLFb. In human lung fibroblasts, muscarinic receptors exert stimulatory effects on collagen synthesis. Prolonged blockade of muscarinic-induced collagen synthesis may contribute to reported beneficial long-term effects of anticholinergics in chronic obstructive pulmonary disease.

Impairment of health-related quality of life in functional dyspepsia and chronic liver disease: the influence of depression and anxiety

BACKGROUND

Health-related quality of life (HRQOL) is a marker of disease severity. Data on the relative impairment of HRQOL in chronic liver disease (CLD) and functional gastrointestinal disorders are lacking and no studies have assessed the link between impairment of HRQOL and psychosocial factors yet.

AIM

To assess predictors for, and the impairment of, HRQOL in CLD and FD.

METHODS

In 181 functional dyspepsia (FD) patients, 204 CLD patients and 337 healthy blood donors, HRQOL was assessed with the Short Form-36 (mental and physical component), and anxiety and depression utilizing the Hospital Anxiety and Depression Scale.

RESULTS

Compared with HC, HRQOL is significantly lower in FD and CLD (P-value for all <0.001). The mental but not physical component of HRQOL was significantly more impaired in FD compared with CLD (P < 0.05). After adjusting for confounders, impairment of mental (P < 0.001) and physical (P = 0.005) component of HRQOL was associated with the severity of CLD and FD. In FD, the multivariate analysis revealed depression and severity of symptoms as the most important predictors of HRQOL (R2 = 21.9 and 7.1). In CLD, the mental component of HRQOL was associated with depression and anxiety (R(2) = 9.9 and 9.7).

CONCLUSIONS

In tertiary care, HRQOL is more severely impaired in FD compared with CLD. Co-morbid psychiatric conditions significantly contribute to the impairment of HRQOL.

[Spectrum of patients in prehospital emergency services. What has changed over the last 20 years?]

BACKGROUND

In Germany the physician staffed emergency systems have announced an increase in rescue missions over the years. The aim of this study is to analyse the development of the spectrum of patients in an emergency system over the last 20 years in order to highlight the significant changes.

METHODS

In a retrospective study we analyzed the prehospital chart views from 2004, 1992 and 1984 with respect to patients' demography, type of rescue mission, degree of internal disease or injury (NACA), state of consciousness (GCS), as well as prehospital interventions performed by prehospital emergency physician.

RESULTS

In 2004 (3,825), the absolute number of missions was 2 and 4 times higher than 1992 (2,114) and 1984 (957), resp. In all of these investigated time periods non-trauma missions (74%; 2,812 vs. 66%; 1,390 vs. 51%; 485) were leading, followed by trauma missions (18%; 690 vs. 22%; 464 vs. 39%; 375), aborted missions (3%; 126 vs. 7%; 154 vs. 6%; 56), and dead on arrival (5%; 197 vs. 5%; 106 vs. 4%; 41). Although, the percentage of patients with NACA IV-VI (39% vs. 50%) or patients with GCS < or =8 (18% vs. 34%) was lower in 2004, the absolute number of patients in each category was higher than in 1984 (NACA IV-VI: 1,434 vs. 448, p<0.01; GCS: 672 vs. 303, p<0.01).

CONCLUSIONS

The results of this study demonstrate, that the percentage of trauma, severely ill/injured or unconscious patients is lower than in previous years. However, the higher absolute numbers of patients demonstrate that the emergency physician now encounters more critically ill/injured, unconscious and trauma patients. It does not seem necessary to question the qualifications for an emergency physician, which have previously been considered essential for the management of acute life-threatening situations.

Neuroendocrine and blood pressure responses to rectal distensions in individuals with high and low visceral pain sensitivity

BACKGROUND

The mechanisms of interindividual variations in visceral pain sensitivity remain poorly understood. We characterized the neuroendocrine responses to rectal distensions in healthy individuals with high vs. low rectal pain sensitivity.

METHODS

Rectal sensory and pain thresholds were determined, and a series of random painful distensions was carried out. Eighteen subjects were stratified into groups with a low rectal pain threshold ("High Sensitivity" group) vs. a high rectal pain threshold ("Low Sensitivity" group) by median split, and were compared with regard to adrenocorticotropic hormone (ACTH) and cortisol, cardiovascular, and emotional responses.

RESULTS

Distensions led to an anticipatory stress response, reflected by elevated baseline anxiety, and increased baseline ACTH and cortisol in both groups. In response to distensions, the "Low Sensitivity" group showed significantly greater ACTH and cortisol concentrations analysis of variance (ANOVA time x group for ACTH: p<.05; for cortisol: p<.01), and elevated diastolic blood pressures (BP) (ANOVA group: p<.01) when compared to the "High Sensitivity" group.

CONCLUSIONS

Painful rectal distensions are associated with a pronounced anticipatory stress response, reflected by elevated anxiety and elevated stress hormones. Individuals with high rectal pain sensitivity differ from those with low pain sensitivity in distension-induced hormonal and blood pressure responses, suggesting that neuroendocrine responses may be relevant to the pathophysiology of visceral hyperalgesia.

Is there a benefit from intensified medical and psychological interventions in patients with functional dyspepsia not responding to conventional therapy?

AIM

In a prospective randomized, controlled trial, to compare the long-term outcome of intensive medical therapy (with or without cognitive-behavioural or muscle relaxation therapy) vs. standard medical therapy in patients with refractory functional dyspepsia (FD), referred to a tertiary referral medical center.

METHODS

A total of 100 consecutive FD patients were allocated to a standardized symptom-oriented 4 month therapy (SMT, n = 24), intensive medical therapy (IMT, medical therapy with testing-for and targeting-of abnormalities of motor-and-sensory function, n = 28) or IMT plus psychological interventions (either progressive-muscle relaxation (IMT-MR, n = 20) or cognitive-behavioural therapy (IMT-CBT, n = 28). The symptom intensity (SI) and health-related quality-of-life (HRQoL) after 12 months were prespecified primary outcome parameters.

RESULTS

After 12 months, significantly greater improvement of SI occurred in patients with IMT-all (with or without psychological interventions) compared with SMT (P < 0.025 vs. IMT-all). IMT, IMT-MR and IMT-CBT alone also resulted in significantly better improvement of the primary outcome parameters (P all < 0.025 vs. SMT). HRQoL significantly improved in all groups with intensive medical therapy but not standard medical therapy. Differences between intensive medical therapy-all and standard medical therapy were not significant. Concomitant anxiety and depression was improved significantly by IMT-CBT (vs. SMT) but not other treatments.

CONCLUSIONS

In FD patients with refractory symptoms, intensified medical management involving function testing and psychological intervention yields superior long-term-outcomes. Additional CBT may be effective for the control of concomitant anxiety and depression.

Disturbed in vitro adrenergic modulation of cytokine production in inflammatory bowel diseases in remission

OBJECTIVE

Psychological stress has been implicated in the pathophysiology of both inflammatory and functional gastrointestinal (GI) diseases. The goal of this study was to address neuroendocrine modulation of cytokine production by peripheral blood cells in GI diseases.

METHODS

We analyzed the in vitro effects of the beta-adrenergic agonist terbutaline and the glucocorticoid agonist dexamethasone on TNF-alpha and IL-10 production by LPS-stimulated monocytes in whole cell blood cultures in patients with inflammatory bowel diseases in remission (N=10), diarrhoea-predominant irritable bowel syndrome (IBS, N=12), patients with a recent gastroenteritis (post-infectious group, N=10), and healthy controls (N=15).

RESULTS

In response to terbutaline, there was a significant increase in IL-10 production (concentration effect: p<0.05), which was diminished in IBD (group effect: p<0.01), comparable in IBS and controls, but enhanced in the post-infectious group (group x concentration effect: p<0.05). In contrast, terbutaline resulted in a concentration-dependent suppression of TNF-alpha production, which was comparable in all groups. Dexamethasone suppressed TNF-alpha production in a dose-dependent manner in all groups, but this effect was significantly more pronounced in post-infectious subjects (group effect: p<0.05).

CONCLUSIONS

In IBD, disturbed adrenergic regulation of IL-10 could be part of the mechanism(s) underlying the modulation of disease activity by psychological stress. Diarrhoea-predominant IBS was not associated with altered adrenergic or glucocorticoid regulation of cytokine production by peripheral blood cells, whereas a recent history of gastroenteritis was associated with disturbed neuroendocrine modulation of cytokine production, which may play role in the pathophysiology of post-infectious IBS.

Measuring treatment satisfaction in patients with primary immunodeficiency diseases receiving lifelong immunoglobulin replacement therapy

BACKGROUND

Treatment satisfaction of patients with primary immunodeficiency diseases receiving hospital-based intravenous (IVIG) or home-based subcutaneous (SCIG) immunoglobulin infusions requires investigation.

OBJECTIVE

Evaluation of the properties and suitability of the Life Quality Index (LQI), as an instrument to assess treatment satisfaction.

METHODS

Patients received weekly SCIG and completed the LQI, two global treatment satisfaction questions and the CHQ-PF50 (children) or the SF-36 (adults) at baseline and 10 months. The LQI was psychometrically evaluated.

RESULTS

The LQI comprised four scales: treatment interference (I), therapy related problems (II), therapy setting (III), treatment costs (IV). Convergent/discriminant validity for scales I, II, III was acceptable, for scale IV moderate. CHQ-PF50 scales behavior, bodily pain, global behavior, global health, mental health, parental impact-emotion significantly correlated with LQI scale II, the family activity scale with LQI scales I, III. SF-36 scale bodily pain significantly correlated with scale III. Internal consistency was good for scales I, II, III, but poor for scale IV. Score values significantly increased for scales I, III, IV in patients switching from IVIG to SCIG.

CONCLUSIONS

Three valid LQI scales were determined. Cost-related questions should be removed due to low reliability. Patients-perceived therapy effectiveness and patient-physician/nurse interaction should be included in the instrument.

Symptom patterns in functional dyspepsia and irritable bowel syndrome: relationship to disturbances in gastric emptying and response to a nutrient challenge in consulters and non-consulters

BACKGROUND

Our aim was to assess the relationship between gastric motor and sensory function and symptom patterns in community subjects and patients with functional dyspepsia (FD) or irritable bowel syndrome (IBS).

METHODS

We recruited 291 asymptomatic blood donors, 151 symptomatic blood donors (recurrent abdominal pain or discomfort), and 40 patients with FD or IBS. Abdominal symptoms were assessed using the bowel disease questionnaire (BDQ) and, in addition, the most bothersome symptom complex identified (dysmotility-type, ulcer-type dyspepsia, or IBS). Gastric emptying time (GET (t(1/2), min)) was measured by (13)C-octanoic breath test and a nutrient challenge performed. Twenty randomly selected asymptomatic blood donors, 48 symptomatic blood donors (30 FD, 18 IBS), and 40 patients (23 FD, 17 IBS) had additional function testing.

RESULTS

GET (t(1/2)) was significantly (p<0.05) longer in blood donors with FD symptoms (99 (6) min) and FD patients (110 (12) min) compared with asymptomatic controls (76.7 (7) min), but was not significant in IBS blood donors or patients. Overall, 25 of 48 blood donors with symptoms and 18 of 40 patients had slow gastric emptying. GET was most delayed in subjects with predominantly dysmotility-type symptoms (167 (36) min v controls; p<0.01). Symptom intensities after a nutrient challenge were significantly higher in FD patients and symptomatic blood donors compared with asymptomatic controls; 14 of 48 blood donors with symptoms and 16 of 40 patients had a symptom response to the nutrient challenge exceeding the response (mean (2SD)) of healthy asymptomatic controls.

CONCLUSION

Gastric emptying and the global symptom response to a standardised nutrient challenge are abnormal in population based (non-health care seeking) subjects with dyspepsia.

Efficacy of artichoke leaf extract in the treatment of patients with functional dyspepsia: a six-week placebo-controlled, double-blind, multicentre trial

BACKGROUND

This study aimed to assess the efficacy of artichoke leaf extract (ALE) in the treatment of patients with functional dyspepsia (FD).

METHODS

In a double-blind, randomized controlled trial (RCT), 247 patients with functional dyspepsia were recruited and treated with either a commercial ALE preparation (2 x 320 mg plant extract t.d.s.) or a placebo. The primary efficacy variable was the sum score of the patient's weekly rating of the overall change in dyspeptic symptoms (four-point scale). Secondary variables were the scores of each dyspeptic symptom and the quality of life (QOL) as assessed by the Nepean Dyspepsia Index (NDI).

RESULTS

Two hundred and forty-seven patients were enrolled, and data from 244 patients (129 active treatment, 115 placebo) were suitable for inclusion in the statistical analysis (intention-to-treat). The overall symptom improvement over the 6 weeks of treatment was significantly greater with ALE than with the placebo (8.3 +/- 4.6, vs. 6.7 +/- 4.8, P < 0.01). Similarly, patients treated with ALE showed significantly greater improvement in the global quality-of-life scores (NDI) compared with the placebo-treated patients (- 41.1 +/- 47.6 vs. - 24.8 +/- 35.6, P < 0.01).

CONCLUSION

The ALE preparation tested was significantly better than the placebo in alleviating symptoms and improving the disease-specific quality of life in patients with functional dyspepsia.

Reflux disease and Barrett's esophagus

Gastroesophageal reflux disease (GERD) is one of the most prevalent gastrointestinal disorders. The key feature of GERD is reflux of gastric contents into the esophagus. Medical treatment with proton-pump inhibitors (PPIs) is well established and is considered the standard treatment. Given the high prevalence of the condition and the excellent response to medical therapy, antireflux surgery is an option for patients with volume reflux that is not properly controlled by medical therapy. Adenocarcinoma is a rare but life-threatening complication of GERD. The only known precursor lesion for esophageal adenocarcinoma is Barrett's esophagus. In recent years, a clearer understanding of the development of Barrett's and of its progression toward invasive cancer has developed. Genetic factors almost certainly determine the individual risk. The length of the Barrett's esophagus segment and the size of a hiatal hernia are associated with the risk of developing high-grade dysplasia and esophageal adenocarcinoma.With regard to the clinical management of GERD patients with Barrett's, endoscopic surveillance at 3-year intervals is now considered appropriate in the absence of dysplasia. In patients with high-grade dyspepsia, the situation is more difficult. While a considerable proportion of these patients may already have invasive cancers, there is also the possibility that there is only focal dysplasia. For this reason, it is justifiable to carry out curative endoscopic resection. Mucosal ablation procedures may also be appropriate, but these still need to be properly investigated in clinical trials.