Edge-to-edge transcatheter valve repair of atrial functional mitral regurgitation positively influences atrial pathology

Introduction

Functional mitral regurgitation (FMR) is the result of an insufficient coaptation of the mitral valve leaflets lacking relevant degeneration or morphological alterations of the valve apparatus. In most patients, this is caused by left ventricular (LV) systolic dysfunction and remodelling (ischemic or non-ischemic). However, a small subset of FMR patients is seen in the context of left atrial (LA) enlargement due to isolated atrial dilation in the absence of a ventricular pathology and has been termed “atrial functional MR” (AFMR) as a distinct etiology of FMR.

The effect of transcatheter mitral valve repair (TMVR) by edge-to-edge-repair (e.g., MitraClip®) on AFMR reduction has not been studied, but it is considered to be effective regarding its effect on the anterior-posterior mitral annular diameter.

Methods

We retrospectively screened all 737 patients treated with TMVR by edge-to-edge repair in our center between January 2013 and April 2019. AFMR was defined as FMR with: (1) relevant LA dilatation, (2) no LV systolic dysfunction or (3) dilatation, (4) no ischemic etiology of FMR. LA mean pressure was invasively measured peri-interventionally before and after device implantation. Echocardiographic assessment was repeated at 1 year follow-up (1yFUP).

Results

Among 350 patients (47.5%) with FMR, 57 patients (16.3%) met the inclusion criteria for AFMR and were included in the data analysis. All patients in the AFMR group (mean age 81.4±5.7 years, 78.9% female) were symptomatic (82.2% functional NYHA class≥III) at baseline and were assessed to be at elevated risk for surgery (mean logistic EuroScore of 24.8±12.0%).

TVMR was successfully performed in all patients without any peri-interventional major complications. At hospital discharge, 78.3% of patients had mild residual MR and 17.4% had no detectable MR. At 1 year, the echocardiographic prevalence of residual moderate MR was 11.4% and 2.9% of patients had severe MR (Figure A). Invasive LA mean pressure measurements were available in 39 patients (68.4%). In average, LA mean pressures decreased from 18.8 mmHg to 12.8 mmHg (p<0.001).

Analysis at 1yFUP showed a significant reduction in LA volume, both at end-systole (79.6±31.9 vs. 66.9±31.8 ml/m2 p<0.001; Figure B) and at end-diastole (61.6±21.5 vs. 50.4±27.37 ml/m2; p<0.01; Figure C). LA ejection fraction increased from 18.8%±12.6% to 30.1%±12.3% in 54.8% of patients. These findings were accompanied by a relevant symptomatic benefit (NYHA class I/II was found in 66.7% of patients at 1 year).

Conclusions

Transcatheter mitral valve repair by edge-to-edge therapy in symptomatic patients with atrial functional mitral regurgitation is safe and capable of a relevant reduction of mitral regurgitation severity accompanied by symptomatic improvement and positive atrial remodeling.

Funding Acknowledgement

Type of funding sources: None.

[Evaluation of mitral regurgitation : How much quantification do we need?]

Severe mitral regurgitation (MR) is associated with increased morbidity and mortality. Thus, the correct evaluation of the underlying etiology, pathomechanism and severity is crucial for optimal treatment. Echocardiography is the predominant diagnostic modality in the clinical routine as it enables grading of mitral regurgitation, which can frequently be achieved by readily available qualitative parameters. Additionally, echocardiography provides several methods to quantify the hemodynamic significance of MR. The effective regurgitation orifice area (EROA) is the quantitative parameter best correlated with clinical events. American and European imaging guidelines both recommend the use of quantitative parameters even though they disagree on the cut-off values for secondary MR. The evaluation of MR should always include an assessment of the adjacent heart chambers in order to be able to assess the impact of volume overload on size and function of the left ventricle and left atrium. The final interpretation of the quantitative parameters requires knowledge of left ventricular volume and ejection fraction. Newer 3D-echocardiographic approaches to quantify MR are less dependent on mathematical assumptions and have shown convincing results in several studies but still lack sufficient clinical validation. As an alternative to echocardiography, for specific indications cardiac magnetic resonance imaging (MRI) has proven to be a systematic and observer-independent method for quantification of MR.

Langevin Dynamics with Spatial Correlations as a Model for Electron-Phonon Coupling

Stochastic Langevin dynamics has been traditionally used as a tool to describe nonequilibrium processes. When utilized in systems with collective modes, traditional Langevin dynamics relaxes all modes indiscriminately, regardless of their wavelength. We propose a generalization of Langevin dynamics that can capture a differential coupling between collective modes and the bath, by introducing spatial correlations in the random forces. This allows modeling the electronic subsystem in a metal as a generalized Langevin bath endowed with a concept of locality, greatly improving the capabilities of the two-temperature model. The specific form proposed here for the spatial correlations produces a physical wave-vector and polarization dependency of the relaxation produced by the electron-phonon coupling in a solid. We show that the resulting model can be used for describing the path to equilibration of ions and electrons and also as a thermostat to sample the equilibrium canonical ensemble. By extension, the family of models presented here can be applied in general to any dense system, solids, alloys, and dense plasmas. As an example, we apply the model to study the nonequilibrium dynamics of an electron-ion two-temperature Ni crystal.

Influence of the serum levels of immunoglobulins on clinical outcomes in medical intensive-care patients

INTRODUCTION

Endogenous immunoglobulins (Igs) are of fundamental importance in the host defense after microbial infections. However, the therapeutic administration of intravenous IgG (IVIgG) has not yet been shown to improve clinical outcomes in patients suffering from sepsis, and in the case of IgM-containing preparations (IVIgGMA) the positive evidence is only weak. Recently published studies implicate that Ig levels on admission could have an impact on the patient's response to IVIg treatment and on outcomes of critically ill patients.

METHODS

In this noninterventional study, the serum levels of IgG, IgM, and IgA were determined in 340 medical patients on ICU admission, and clinical outcomes were prospectively recorded (ICU mortality, need for renal replacement therapy (RRT), need for mechanical ventilation, substitution of coagulation factors, and amount of red cell transfusions). Patients were prospectively grouped according to their main reason for ICU admission (sepsis, respiratory failure, cardiovascular diseases, acute renal failure, postoperative condition, state after cardiopulmonal resuscitation, gastrointestinal diseases, and others).

RESULTS AND DISCUSSION

There was no correlation between the Ig levels on admission and ICU mortality neither in the total cohort of medical ICU patients nor in any prespecified subgroup. However, in a logistic regression model that was adjusted for APACHE II score on admission, an increase in serum IgG was associated with a reduced need for mechanical ventilation in patients suffering from cardiovascular disease. On the other hand, in patients suffering from sepsis, an increased level of IgM was linked to an increased administration of coagulation factors.

CONCLUSION

Our data do not support the hypothesis that serum levels of immunoglobulins are linked to mortality in medical ICU patients.

Diagnostic and prognostic value of bone biomarkers in progressive knee osteoarthritis: a 6-year follow-up study in middle-aged subjects

OBJECTIVE

To determine the value of bone markers in early-stage progressive knee osteoarthritis (OA), a population-based cohort of middle-aged subjects with chronic knee complaints was followed over 6 years (two consecutive two 3-year periods).

METHODS

Tibiofemoral (TF) and patellofemoral (PF) radiographs were graded in 128 subjects (mean age at baseline 45 ± 6.2 years) in 2002, 2005 and 2008. Bone formation was assessed by the serum concentration of procollagen type I amino-terminal propeptide (sPINP); bone resorption by the level of the C-terminal cross-linked telopeptides of type I collagen (sCTx-I); and bone mineralization by the values of osteocalcin (sOC) by electrochemiluminescence immunoassay. A novel marker of bone resorption, urinary osteocalcin midfragments (uMidOC), was assayed using enzyme linked immunosorbent assay (ELISA).

RESULTS

Several diagnostic associations were found between the bone markers (PINP, OC, MidOC) and progressive OA expressed by TF osteophytosis. The increasing output of MidOC demonstrated several-fold higher risk for progressive TF osteophytosis [odds ratio (OR) 5.32; 95% confidence interval (CI) 1.41-20.06, P = 0.014] than other bone markers. The values of PINP had prognostic value for subsequent more severely expressed knee OA progression [r(s) = 0.460, P = 0.005].

CONCLUSIONS

Bone metabolism is activated in early-stage knee OA. OA progression was preceded by the enhanced bone formation (by PINP) and accompanied by the activation of bone formation (by PINP), non-collagenous bone resorption (by MidOC), as well as by changes in mineralization (by OC). All three bone markers had diagnostic value, and one of them, PINP, had also a predictive value for knee OA progression, especially for progressive osteophytosis.

Large-scale meta-analysis of interleukin-1 beta and interleukin-1 receptor antagonist polymorphisms on risk of radiographic hip and knee osteoarthritis and severity of knee osteoarthritis

OBJECTIVE

To clarify the role of common genetic variation in the Interleukin-1β (IL1B) and Interleukin-1R antagonist (IL1RN) genes on risk of knee and hip osteoarthritis (OA) and severity of knee OA by means of large-scale meta-analyses.

METHODS

We searched PubMed for articles assessing the role of IL1B and IL1RN polymorphisms/haplotypes on the risk of hip and/or knee OA. Novel data were included from eight unpublished studies. Meta-analyses were performed using fixed- and random-effects models with a total of 3595 hip OA and 5013 knee OA cases, and 6559 and 9132 controls respectively. The role of ILRN haplotypes on radiographic severity of knee OA was tested in 1918 cases with Kellgren-Lawrence (K/L) 1 or 2 compared to 199 cases with K/L 3 or 4.

RESULTS

The meta-analysis of six published studies retrieved from the literature search and eight unpublished studies showed no evidence of association between common genetic variation in the IL1B or IL1RN genes and risk of hip OA or knee OA (P>0.05 for rs16944, rs1143634, rs419598 and haplotype C-G-C (rs1143634, rs16944 and rs419598) previously implicated in risk of hip OA). The C-T-A haplotype formed by rs419598, rs315952 and rs9005, previously implicated in radiographic severity of knee OA, was associated with reduced severity of knee OA (odds ratio (OR)=0.71 95%CI 0.56-0.91; P=0.006, I(2)=74%), and achieved borderline statistical significance in a random-effects model (OR=0.61 95%CI 0.35-1.06 P=0.08).

CONCLUSION

Common genetic variation in the Interleukin-1 region is not associated with prevalence of hip or knee OA but our data suggest that IL1RN might have a role in severity of knee OA.

A meta-analysis of interleukin-6 promoter polymorphisms on risk of hip and knee osteoarthritis

OBJECTIVE

Interleukin-6 is a pro-inflammatory cytokine involved in the pathogenesis of osteoarthritis (OA). We investigated the role of two single nucleotide polymorphisms (SNPs) mapping to the promoter of the IL-6 gene on genetic susceptibility to hip and knee OA.

METHODS

The -174G/C (rs1800795) and -597G/A (rs1800797) SNPs, implicated in the literature in risk of hip and hand OA, were genotyped in 2511 controls, 1101 hip OA cases and 1904 knee OA cases from four cohorts from the UK and Estonia. Data were analysed in conjuntion with published data on rs1800797 from the Genetics of OA and Lifestyle study (UK) on 791 controls, 1034 knee and 997 hip OA cases and rs1800795 data on 75 hip OA cases and 96 controls from Italy. Cases included both radiographic OA only and radiographic and symptomatic OA. Fixed and random-effects meta-analysis models were tested.

RESULTS

No significant association was found with hip OA or knee OA with either SNP nor with the haplotypes formed by them. For individual SNPs the smallest P-value for hip OA was observed using a random-effects model for rs1800795 OR(Gallele)=1.066 (95% CI 0.89-1.28) P<0.49, and significant heterogeneity between cohorts (I(2)=65%, P<0.034) was detected. For knee OA the smallest P-value was seen for rs1800797 OR(Aallele)=1.055 (95%CI 0.98-1.12) P<0.18, no significant heterogeneity was observed (I(2)=0%, P<0.68).

CONCLUSIONS

Our data do not support a role for the -174 and -597 IL-6 promoter polymorphisms in genetic susceptibility to knee or hip OA in Caucasian populations.

Characteristics of progressive renal disease

Virtually all renal diseases progress to terminal renal failure relatively independently of the initial disease. Arresting the rate of the deterioration of kidney failure has a great impact on reducing the number of patients reaching the stage of expensive renal replacement therapy. Understanding the mechanisms of the progression of kidney disease has greatly been improved during recent years. The nature of the progressive renal damage with various etiologies includes various well-known factors where hemodynamics, renin-angiotensin system (RAS) and progressive proteinuria play the central roles. Proteinuria has to be shown as an independent risk factor for renal disease progression. Also, disturbances in lipid metabolism as well as the later structural lesions contribute to the progression. Various modalities have been used for the prevention of progressive renal disease, e.g. low-protein diet, antihypertensive therapy, antifibrotic therapy. Many recent experimental and clinical studies have shown that besides the systemic blood pressure lowering effect, RAS blocking agents provide renal protective effects via direct, hemodynamic, and indirect, non-hemodynamic, pathways: (1) lowering intraglomerular capillary hydraulic pressure, and increasing the glomerular ultrafiltration coefficient; (2) lowering proteinuria; (3) lowering hyperlipidemia; (4) diminishing kidney growth; (5) diminishing infiltration of macrophages; (6) downregulation of proinflammatory cytokines. Therefore, RAS blocking agents are widely prescribed not only for antihypertensive but also for renoprotective purposes in diabetic and non-diabetic nephropathies.

IgG binding sites on human Fc gamma receptors

The structure for the three human Fc gamma receptors classes Fc gamma RI (CD64), Fc gamma RII (CD32) and Fc gamma RIII (CD16) has been well characterized. Here the IgG binding sites on Fc gamma RII and Fc gamma RII with their responsive FG, BC and C'/E loops on the membrane proximal domains are described in detail. For Fc gamma RI the second extracellular domain is suggested as a key structure of IgG binding. The lower hinge regions of human and murine IgG binding to these Fc receptors and their structural relationship in Fc gamma R-IgG interactions are discussed. The potential of inhibiting the pathophysiological effects of Fc gamma receptors by blocking studies are considered for future therapeutic modalities.

The IgG Fc receptor family

IgG immune complexes are of central importance in the humoral immune system and strongly implicated in the pathogenesis of hematologic and rheumatic autoimmune disorders. Cross-linking of receptors for the Fc domain of IgG antibodies (FcgammaRs) triggers a wide variety of effector functions including phagocytosis, antibody-dependent cellular cytotoxicity, and release of inflammatory mediators, as well as immune complex clearance and regulation of antibody production. In this way, FcgammaR provide an essential feedback between the humoral and cellular immune response. In the past, significant advances have been made in the molecular dissection of FcgammaR function using cellular transfection systems. Current approaches designed to target and change individual FcgammaR genes in mice have given further insight into their specific contributions to systemic processes, also indicating them to be important immunoregulatory receptors involved in various disease states of allergy, autoimmunity, and inflammation. Future work on targeting FcgammaR binding sites in combination with humanized FcgammaR mouse models will lead to novel therapeutic strategies in the treatment of IgG-mediated human disease in which FcgammaR activation plays an integral part.

The binding epitopes of human CD16 (Fc gamma RIII) monoclonal antibodies. Implications for ligand binding

Numerous mAbs have been generated against Fc gamma RIII (CD16), the low-affinity receptor for the Fc part of IgG. Most of the mAbs recognize both the receptor isoforms, transmembranous Fc gamma RIIIA, and glycosylphosphatidylinositol-linked Fc gamma RIIIB. Binding epitopes of some of the mAbs that differentiate between the two neutrophil Ag (NA) alleles of Fc gamma RIIIB (CLB-Gran11 against NA1; GRM1, BL-LGL/1 against NA2 allele) have been mapped on the first, membrane-distal domain of CD16. We demonstrate that mAbs 3G8, B88-9, CLB-Gran1, MEM-154, and LNK16 almost completely block the receptor's interaction with IgG. Using chimeric Fc gamma RIIIB/Fc epsilon RI receptors and molecular modeling, we localized the epitopes of 3G8 and B88-9 on the putative FG loop of the membrane-proximal Ig-like domain, which we have previously identified as the major binding site for IgG. The epitopes of CLB-Gran1 and MEM-154 are shown to reside in proximity to the FG loop (probably BC or C'E loop). The blocking mAb LNK16 was detected to be directed against the putative C' beta-sheet of the membrane-proximal domain, suggesting that additional residues may be involved in IgG binding of Fc gamma RIII.

The binding epitopes of human CD16 (Fc gamma RIII) monoclonal antibodies. Implications for ligand binding

Numerous mAbs have been generated against Fc gamma RIII (CD16), the low-affinity receptor for the Fc part of IgG. Most of the mAbs recognize both the receptor isoforms, transmembranous Fc gamma RIIIA, and glycosylphosphatidylinositol-linked Fc gamma RIIIB. Binding epitopes of some of the mAbs that differentiate between the two neutrophil Ag (NA) alleles of Fc gamma RIIIB (CLB-Gran11 against NA1; GRM1, BL-LGL/1 against NA2 allele) have been mapped on the first, membrane-distal domain of CD16. We demonstrate that mAbs 3G8, B88-9, CLB-Gran1, MEM-154, and LNK16 almost completely block the receptor's interaction with IgG. Using chimeric Fc gamma RIIIB/Fc epsilon RI receptors and molecular modeling, we localized the epitopes of 3G8 and B88-9 on the putative FG loop of the membrane-proximal Ig-like domain, which we have previously identified as the major binding site for IgG. The epitopes of CLB-Gran1 and MEM-154 are shown to reside in proximity to the FG loop (probably BC or C'E loop). The blocking mAb LNK16 was detected to be directed against the putative C' beta-sheet of the membrane-proximal domain, suggesting that additional residues may be involved in IgG binding of Fc gamma RIII.

The IgG binding site of human FcgammaRIIIB receptor involves CC' and FG loops of the membrane-proximal domain

Fc gamma receptors for the Fc part of IgG are the mediators for antibody effector functions. FcgammaRIII and FcgammaRII are low affinity receptors that, through the interaction with immune complexes, initiate a variety of immunological responses, such as phagocytosis, antibody-dependent cellular cytotoxicity, and release of inflammatory mediators. We set out to define the IgG binding site on human FcgammaRIII. We assumed that potential beta-turns in Ig-like domains are the most probable determinants for ligand binding, and chimeric FcgammaRIIIB/FcepsilonRI receptors as well as single residue mutants were constructed in these regions of FcgammaRIIIB. Substitution of four amino acids in the membrane-proximal domain (Gln126, Arg156, Lys162, Val164) resulted in decreased binding of human IgG1. Lys162 and Val164 were found also to be crucial for the interaction with the IgG-binding inhibitory monoclonal antibody 3G8. In a putative three-dimensional model constructed in this study, these residues map on the CC loop (Gln126), on F beta-sheet (Arg156), and on the FG loop (Lys162, Val164). Our data are consistent with the study about human FcgammaRII (Hulett, M. D., Witort, E., Brinkworth, R. I., McKenzie, I. F. C., and Hogarth, P. M. (1994) J. Biol. Chem. 269, 15287-15293), suggesting that common structural determinants, i.e. FG loop or the GFC surface of the membrane-proximal domain, can be involved in interactions with IgG by both low affinity receptor classes FcgammaRII and FcgammaRIII.

A 12-year follow-up study of chronic gastritis and Helicobacter pylori in a population-based random sample

BACKGROUND

The study is a 12-year endoscopic follow-up investigation on the course of chronic gastritis and Helicobacter pylori infection in a sample of 81 Estonian people.

METHODS

The series is a subset from a random sample of 227 subjects in whom a gastroduodenal endoscopy had been done. The grade of superficial gastritis (SG), atrophy, and colonization of the mucosa by H. pylori was evaluated in biopsy specimens from both antrum and corpus in accordance with the principles of the Sydney System.

RESULTS

The healing rate of the H. pylori and gastritis was 0.3% (3 of 81); H. pylori colonization with gastritis developed in 5 of 81 during the follow-up. The mean prevalence of atrophic gastritis (AG) was three times more common in the corpus than in the antrum on the average. The formation of new cases of AG and the disappearance of AG were quite equal during the follow-up, and the overall changes in the grade of SG and atrophy were slow. The mean life span of corpus AG was nearly three times as long as that of antrum AG. In the antrum the grade of chronic inflammation correlated positively with the grade of H. pylori colonization. In cases of SG a low grade of colonization of H. pylori in the antral mucosa in connection with moderate inflammation predicted a reduction or even a healing of gastritis in the long term.

CONCLUSIONS

New H. pylori infections with subsequent gastritis may occur in adulthood; a healing of gastritis occurs but is a quite rare event in the course of the 12-year follow-up. Further, in the present random sample of Estonian people atrophic corpus gastritis did not show an overall progression, in contrast to our earlier findings.

Lactose malabsorption in Khants in western Siberia

BACKGROUND

We wanted to estimate the prevalence of selective lactose malabsorption (SLM) in Khants, a small Finno-Ugric population living in Western Siberia who have traditionally consumed no milk in adulthood.

METHODS

A total of 80 Khants, aged 8-57 years and living on the middle reaches of the River Ob, were studied. The diagnosis was based on a lactose tolerance test; general malabsorption was excluded by a glucose-galactose tolerance test whenever possible. In six subjects electronmicroscopic examination of the duodenal mucosa was performed.

RESULTS

The prevalence of SLM in the Khants was 94%.

CONCLUSION

This is the highest prevalence found in the previous Soviet Union.

Management of lactose intolerance

The management of lactose intolerance comprises two parts: (1) the basic principles of treatment in persons intolerant to a dietary dose of lactose, and (2) main manoeuvres to reduce the lactose content in food, and/or consumption of special products of milk or exogenous lactase enzyme. The tactics of management depend on the type of hypolactasia, the severity of intolerance, and on the age of the patient. Special attention is paid to the development of lactose intolerance in some patients via iatrogenic mechanisms such as certain drugs, gastric surgery and ionizing radiation.

Metabolism of lactose in the human body

The article describes the metabolism of lactose in both normo- and hypolactasia in the human body. Attention is drawn to the differences in lactose tolerance among lactose malabsorbers.

Hydrophobic domains affect the collagen-binding specificity and surface polymerization as well as the virulence potential of the YadA protein of Yersinia enterocolitica

The YadA surface protein of enteropathogenic Yersinia species contains two highly hydrophobic regions: one close to the amino terminal, and the other at the carboxy-terminal end of the YadA polypeptide. To study the role of these hydrophobic regions, we constructed 66 bp deletion mutants of the yadA genes of Yersinia enterocolitica serotype O:3 strain 6471/76 (YeO3) and of O:8 strain 8081 (YeO8). The mutant proteins, YadAYeO3-delta 83-104 and YadAYeO8-delta 8O-101, lacked 22 amino acids from the amino-terminal hydrophobic region, formed fibrillae and were expressed on the cell surface. Bacteria expressing the mutated protein lost their auto-agglutination potential as well as their collagen-binding property. Binding to fibronectin and laminin was affected differently in the YeO3 and the YeO8 constructs. The deletion did not influence YadA-mediated complement inhibition. Loss of the collagen-binding property was associated with loss of virulence in mice. We also constructed a number of YadAYeO3 deletion mutants lacking the hydrophobic carboxy-terminal end of the protein. Deletions ranging from 19 to 79 amino acids from the carboxy terminus affected polymerization of the YadA subunits, and also resulted in the loss of the YadA expression on the cell surface. This suggests that the carboxy terminus of YadA is involved in transport of the protein to the bacterial outer surface.

Detection of cytomegalovirus DNA in cells from synovial fluid and peripheral blood of patients with early rheumatoid arthritis

OBJECTIVE

To study the role of cytomegalovirus (CMV) in the etiology of rheumatoid arthritis (RA).

METHODS

Polymerase chain reaction (PCR), immunoperoxidase staining for CMV specific antigens, virus isolation and antibody assays were applied to study samples from patients with RA of less than one year's duration.

RESULTS

By PCR, CMV DNA was detected in granulocytes from 3 of 24 synovial fluid (SF) samples and in 10 of 43 peripheral blood samples of patients with RA. These figures are not significantly different from those observed for the control groups (reactive arthritis, other arthropathies, healthy individuals). By immunoperoxidase staining, no evidence for the CMV antigens was observed in the SF cells. All the virus isolations were negative, and the level of CMV specific circulating antibodies in RA was not different from that in the other groups.

CONCLUSION

In spite of the negative results, the potential role of CMV in the etiology of RA cannot be totally excluded on the basis of these results; the mutual contribution of the triggering agent and the host response in genetically susceptible individuals is discussed.

Faecal short-chain fatty acids in breast-fed and bottle-fed infants

Faecal short-chain fatty acids (SCFAs) were determined in 49 infants on three occasions, i.e. at ages three and six days and two months. At two months, the breast-fed infants had a significantly higher proportion of acetic acid in the SCFA spectra than the bottle-fed infants. The data suggest that the composition of the intestinal microflora in most breast-fed infants is characterized by a high relative content of acetic acid in faecal SCFAs. This may be associated with protection against diarrhoea and respiratory infections in the infant.

In-vivo-generated fusion promoters in Pseudomonas putida

Plasmid pEST1463 carrying the promoterless pheBA operon was cloned into Pseudomonas putida PaW85, and phenol-utilizing colonies were isolated on minimal plates containing phenol as the only carbon and energy source. In these clones, chromosomally located Tn4652 was transposed upstream from the coding sequencing of pheA (encoding phenol monooxygenase). Sequence analysis together with mapping of the transcription start point of the pheBA operon in the recombinant plasmids revealed that fusions of the -10 sequences present in the pheBA operon and -35 sequence located in the terminal inverted repeats of Tn4652 had generated functional promoters under selective pressure in P. putida cells. These promoter sequences show similarity to the Escherichia coli RNA polymerase sigma 70 promoter consensus sequence. In three of the six fusion promoters studied, the generation combined two distinct events: transposition of Tn4652 into DNA containing potential -10 sequences and point mutations in these sequences. These mutations made the -10 sequences more like the sigma 70 promoter consensus sequences.

Chronic gastritis: progression of inflammation and atrophy in a six-year endoscopic follow-up of a random sample of 142 Estonian urban subjects

To study the prevalence and course of chronic gastritis (CG), 142 adult subjects collected at random from an Estonian urban area were endoscopically and bioptically examined at a six-year interval. The histology of the antral and corpus mucosae was evaluated by grading gastritis without ("superficial gastritis"; SG) and with atrophy ("atrophic gastritis"; AG) into mild, moderate and severe categories. A total of 135 (95%) and 139 (98%) subjects showed CG in the 1st and 2nd examinations, respectively. The CG healed in one subjects (0.7%), and in 5 out of 7 subjects with normal stomach in the 1st examination the CG started during the follow-up. No change in the severity of CG was seen in 24% of subjects with gastritis in the 1st examination. The main trend of CG was a slow, "one-step progression" in severity of inflammation and appearance of atrophy and intestinal metaplasia. Inflammation progressed significantly, especially in the young age groups and in the antrum in particular. The prevalence of AG increased linearly with age in corpus (mean annual risk 1.25%). Parietal cell antibodies (PCA) were found in 2 subjects in the 1st examination, and a further 2 subjects developed these antibodies later. Three of four PCA-positive subjects belonged to a subgroup of 8 elderly subjects who had corpus AG at both examinations and who also showed normal or normalizing mucosa in the antrum. It is concluded that CG is a slowly progressive disease advancing with time and, once started, rarely healing spontaneously.

The occurrence and extent of Helicobacter pylori colonization and antral and body gastritis profiles in an Estonian population sample

A series of 143 subjects representing an Estonian urban population was examined for the occurrence and extent (absent, mild, moderate, severe) of Helicobacter pylori colonization in antral and body biopsy specimens (Giemsa staining). These data were correlated with the presence and grade of chronic gastritis (normal, mild, moderate, or severe superficial chronic gastritis; mild, moderate, or severe atrophic gastritis) in the antrum and the body. Gastritis of any grade was found in the antrum and/or the body in 140 (98%) subjects. The overall extent of H. pylori colonization in the whole series did not differ between the antrum and the body. Of 93 subjects with superficial gastritis, H. pylori was found in the antrum and/or the body in 87 (94%) cases. Of 47 subjects with atrophic gastritis in the antrum and/or the body. H. pylori was not found in 12 (25%). In subjects with gastritis the absence of H. pylori either in the antrum or in the body was relatively common (in 30 of 143 subjects). The grade of superficial gastritis showed a highly significantly positive correlation with the extent of H. pylori colonization in the antrum but not in the body. Correspondingly, the grade of atrophic gastritis in the antrum correlated negatively to the grade of colonization. The total absence of H. pylori was particularly associated with the absence of gastritis in the antrum. Conversely, severe body H. pylori colonization was found in subjects who had atrophic antral gastritis, and severe antral colonization in subjects who had at least moderate superficial antral gastritis and who showed a coexistent normal or slight superficial gastritis in the body.(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of vagotomy and antrectomy on serum pepsinogens I and II

Ninety-seven consecutive patients with gastric surgery for peptic ulcer were studied; 86 had duodenal ulcer (DU), and 11 gastric ulcer (GU). DU patients were surgically treated by proximal vagotomy, proximal vagotomy and pyloroplasty, truncal vagotomy and pyloroplasty, or truncal vagotomy and antrectomy. All GU patients were operated on by the Billroth I method. Serum pepsinogen I(S-PG I), serum pepsinogen II (S-PG II), basal acid output (BAO), and maximal acid output (MAO) were determined before and 3 months and 1 year after the operation. The mean preoperative S-PG I concentration in DU patients (154 +/- 7 micrograms/l; mean +/- SE) was significantly higher than that (97 +/- 9 micrograms/l) in GU patients (p less than 0.001). A significant decrease in the mean S-PG I concentration in DU patients was seen 3 months (92 +/- 6 micrograms/l) and 1 year (66 +/- 4 micrograms/l) after the operation (p less than 0.001). This change did not depend on the type of vagotomy. However, this decrease was not seen in all individual patients as it was in BAO values. Moreover, the mean BAO decrease was much greater at 3 months (7% of the preoperative value) and 1 year (23%) after the operation than the respective decrease in S-PG I concentration. There was also no correlation between S-PG I and acid output (BAO and MAO) before and after the operation. In GU patients the decrease in mean S-PG I value after the Billroth I operation was smaller than in DU patients after vagotomy.(ABSTRACT TRUNCATED AT 250 WORDS)

Distribution of serum gastrin in different forms of gastritis among Estonian population

Gastrin level was measured in frozen serum samples of 215 adult Estonians, who took part in a representative population study in 1979, and were followed-up in 1985. Gastric morphology was verified by multiple biopsy specimens from the fundal and antral parts of the stomach, obtained at direct-vision gastroscopy. Certain combinations of antral-body mucosa were revealed which have, and which do not have a significant influence on the fasting gastrin levels. Low values might be observed in subjects having severe atrophic gastritis simultaneously in fundal as well as in antral area. However, in others low concentration of gastrin was seen without any (or without severe) changes of the mucosa. Therefore different factors as duodenal gastrin-producing cells, several molecular forms of gastrin, age of the person seems to contribute to the total serum gastrin level besides the gastric mucosa. High values of gastrin are characteristic to normal antral mucosa accompanied by moderate or severe fundal gastritis.

Relation of parietal cell and thyroid antibodies to the state of gastric mucosa and basal serum gastrin levels during a 6-year follow up

Two groups of volunteers (199 in total, 149 of whom were a random sample of an urban population) were examined twice, with a 6-year interval, for the occurrence of parietal cell antibody (PCA) and thyroid microsomal antibodies (TMA). The antibody findings were compared with the antral and fundal gastric mucosal state, and with the fasting serum gastrin-17 level. During the study period, two new PCA and four new TMA cases appeared. There were no significant changes in the state of gastric antral/fundal mucosa in relation to PCA and/or TMA persistence or appearance, as compared with the gastric mucosa changes in the whole random population sample. However, a good correlation was observed between PCA and basal serum gastrin elevation.

Output of bacterial metabolites as a diagnostic means

Output of bacterial metabolites reflects not only the number but the metabolic activity of certain microorganisms. In case of excess of a substrate one can observe the increased output of metabolite(s) without the overgrowth of intestinal bacteria. This matter is used for detection of malabsorption of some carbohydrates (lactose, glucose) by increased excretion of hydrogen in expired air. Another group of so-called breath tests (14C-cholylglycine, 14C-xylose) is designed to detect the bacterial overgrowth in the small intestine by measuring the rise of the concentration of 14CO2 in alveolar air. All the tests basing on the decomposition of the test substance by intestinal bacteria, have some limitations. Little is known about the microorganisms decomposing the different test substances. Significant correlations between the urinary phenols (p-cresol, phenol) and certain groups of mucosal flora (staphylococci, bacteroides) of the small intestine of rats could be found. Therefore one suggests that elucidating the origin of a bacterial metabolite is still possible in some instances, although very complicated. In conclusion, the authors refer to several reasons for failure to obtain correlations between the output of the metabolite(s) and data of bacteriological investigation.

The relationship of parietal cell, gastrin cell, and thyroid autoantibodies to the state of the gastric mucosa in a population sample

The occurrence of tissue autoantibodies in relationship to fundal and antral gastritis was examined in an Estonian rural population sample, consisting of 227 persons 15 to 69 years of age. The state of the gastric mucosa was verified with multiple biopsy specimens obtained at direct-vision gastroscopy. Isolated fundal gastritis was characterized as the presence of parietal cell (PCA) and/or thyroid antibodies. PCA was seen only in persons with normal antral mucosa. On the other hand, gastrin cell antibodies (GCA) showed no correlation to the extent of antral gastritis, being seen in normal antrum or in superficial or slight atrophic gastritis but not in moderate or severe gastritis. The findings of our present study thus strengthen the view that the occurrence of PCA is mainly limited to isolated fundal gastritis and excludes the occurrence of antral gastritis. On the other hand, an association of GCA and antral gastritis could not be established.

Serum pepsinogen I and the state of gastric mucosa in an Estonian population sample

Seventy-seven adult subjects from a rural population were examined by gastroscopic biopsy and serum pepsinogen I (PG I) determination. A new radioimmunoassay method for PG I determination, based on enzymatic iodination and the double antibody solid-phase technique, was used. A highly significant correlation (r = 0.488, p less than 0.001) between the state of the fundal mucosa and the PG I level was observed. In persons with severe or moderate forms of atrophic fundal gastritis the PG I values were notably lower than those of the other groups. Good differentiation of persons with normal fundal mucosa and with severe fundal gastritis was obtained. In subjects with a normal fundal mucosa the PG I values were significantly higher in men (130 +/- 48 micrograms/l) than in women (87 +/- 17 micrograms/l). A decline in serum PG I level with age was observed. In patchy gastritis the PG I value is helpful in assessing the state of the fundal mucosa.

Epidemiology and dynamics of gastritis in a representative sample of an Estonin urban population

The epidemiology and dynamics of gastritis were studied in a representative sample of an urban population of Estonia. The sample consisted of 227 subjects 15-69 years old who were examined by direct-vision endoscopic biopsy, and the data were subjected to dynamic evaluation by stochastic principles. The prevalence of antral gastritis (64%) was similar to but that of body gastritis (62%) higher than that in other population samples studied by us. Correspondingly, the prevalence of atrophic antral and body gastritis was high: 38% and 37%, respectively. The prevalence of atrophic gastritis in the antrum and body increased significantly with age. On the other hand, no sex dependence of gastritis could be demonstrated. The prevalence of gastritis mainly affecting the body (32%) was significantly higher in the present than in the other Estonian sample (19%) studied by us. Complete loss of normal body glands was found in 14 subjects, and in 8 of these the antrum was normal or only slightly altered (type A gastritis). The prevalence of gastritis mainly affecting the body increased significantly with age, whereas that of gastritis mainly affecting the antrum decreased. Dynamic evaluation disclosed two basic dynamic patterns similar to those found in other population samples: the age-specific prevalences of gastritis increased with age according to the Poisson process, and gastritis started in the antrum at a younger age, but its progression was more rapid in the body mucosa. Dynamically, the chief finding of the sample was markedly more rapid progression of the body gastritis than in other samples, which explains the high prevalence of gastritis mainly affecting the body mucosa (type A gastritis) in the present series.

Dynamics of antral and fundal gastritis in an Estonian rural population sample

The random population sample collected from an Estonian rural district, and in which antral and fundal gastritis was studied by means of direct vision biopsy technique, was subjected to stochastic analysis identical to that performed earlier on a Finnish representative population sample. Antral gastritis started at an earlier age than fundal gastritis. The antral and fundal age-dependent score lines, which illustrate the dynamic behaviour of each population sample as a whole, nearly meet at later age, indicating that the progression of fundal gastritis is more rapid than that of antral gastritis. The prevalence of fundal gastritis was somewhat lower in this material than in the Finnish rural population sample. However, the age-adjusted score values did not significantly differ in these population samples.

The production of urinary phenols by gut bacteria and their possible role in the causation of large bowel cancer

Epidemiological evidence is presented to relate the amount of dietary meat to the risk of large bowel cancer; it has been suggested that this may be due to the production of cocarcinogenic volatile phenols by intestinal bacteria from tyrosine. This paper describes preliminary experiments to test this suggestion. In vitro, aerobic bacteria tended to produce phenol from tyrosine while anaerobic bacteria produced p-cresol. Urine from 10 normal healthy persons contained a mean of 9.8 mg phenol/day and 51.8 mg p-cresol/day. Results from studies on patients with ileostomy, colostomy, and diverticular disease indicated that p-cresol is largely produced by the anaerobic flora of the left colon while phenol was produced in the ileum (when colonized) and cecum. In patients with familial polyposis the activity of the aerobic flora was apparently normal but there was greatly reduced amounts of p-cresol produced. The amounts of urinary volatile phenols in six patients with newly diagnosed large bowel cancer were not different from the normal values, indicating that cocarcinogenic phenols were unlikely to be a major cause of the disease.

Prevalence of antral and fundic gastritis in a randomly selected group of an Estonian rural population

The state of the gastric antral and the fundic mucosa was examined by gastroscopic biopsy in randomly selected 16-69-year-old subjects of a rural medical district. Fundic gastritis was found in 45% of the series, being superficial in 25% and atrophic in 20%. Antral gastritis occurred in 68%, being superficial in 39% and atrophic in 29%. The occurrence of antral gastritis was more frequent (XZ=15.25; df=1; p less than 0.001) than that of fundic gastritis. Antral gastritis and normal fundic mucosa were found in 32% and isolated fundic gastritis in 10% of the series. In the cases in which gastritis had affected both gastric regions, the changes quite often reflected different stages of the disease. The fundic and antral mucosae were normal only in 22% of the subjects examined.