International variation in the definition of 'main condition' in ICD-coded health data.

Hospital-based medical records are abstracted to create International Classification of Disease (ICD) coded discharge health data in many countries. The 'main condition' is not defined in a consistent manner internationally. Some countries employ a 'reason for admission' rule as the basis for the main condition, while other countries employ a 'resource use' rule. A few countries have recently transitioned from one of these approaches to the other. The definition of 'main condition' in such ICD data matters when it is used to define a disease cohort to assign diagnosis-related groups and to perform risk adjustment. We propose a method of harmonizing the international definition to enable researchers and international organizations using ICD-coded health data to aggregate or compare hospital care and outcomes across countries in a consistent manner. Inter-observer reliability of alternative harmonization approaches should be evaluated before finalizing the definition and adopting it worldwide.

Autoimmune markers in lymphoid malignancies.

Chronic immune stimulation such as Helicobacter pylori (hp) infection, Sjögren's syndrome or coeliac disease may initiate non-Hodgkin lymphoma (NHL). The opposite (appearance of autoimmunity) has also been reported. The aim of this study was to describe the pattern of these immune markers in patients with lymphoid malignancies. Sera from 96 patients with NHL (median age 72, range 38-88, F/M 41/55) were analysed with ELISA to determine the frequency of antibodies against guinea pig (gp) and human recombinant (hr) transglutaminase type 2 (Tg2), and hr factor XIII subunit a* (part of the Tg-family), extractable nuclear antigen (ENA), and hp. As hp antibodies decrease in younger age cohorts a sex- and age-matched control group of 768 persons was used. The control population for transglutaminase antibodies consisted of 59 blood donors, (median 42 years, range 19-65) was analysed with a commercial kit. Gp-Tg2-IgG positivity was documented in 72% and hr-Tg2-IgG positivity in 15% (5% positive controls for both; P < 0.001 and ns, respectively). For IgA 3% had gp-Tg2 and 4% hr-Tg2 (5% in controls: ns for both). Anti-FXIII-IgA positivity was found in 22% (5% in controls; P = 0.03). Unspecific anti-ENA-IgG positivity was found in 24% (P < 0.001), while only 2% had specific ENA autoantibodies. Moreover, 36% were positive for anti-hp-IgG, while controls were positive in 54% (P < 0.001). The frequency of unspecific autoantibodies was increased. No differences could be noted in specific autoantibodies (hr-Tg2-IgA). In contrast, fewer than expected were anti-hp-positive. A defective immune response, similar to that in autoimmune diseases, could contribute to the pathogenesis of lymphoid malignancies.

Progress and regression within primary Sjögren's syndrome.

The purpose of this review is to give a modern view and an update of important areas in primary Sjögren's syndrome (SS), which may be the most common of the autoimmune systemic rheumatic diseases. Interest in aspects of primary SS including clinical manifestations, pathogenesis, aetiology, treatment, prognosis, etc has increased during the past three decades, the volume of scientific papers and the number of theses being the indicators. However, only a fraction of the money that is used for research into rheumatoid arthritis (RA) is used for SS, and the statement that SS is under-diagnosed, under-treated and under-researched will still be valid for several years to come. The topics that are focused on in this review are: (a) clinical areas with subsections on signs and symptoms, terminology, predictors for development of non-Hodgkin malignant lymphoma (NHML) and prognosis, (b) treatment, (c) the Danger model (aetiopathogenesis) and (d) pathology, including immunoglobulin G4 (IgG4)-positive cells.

Lymphoma and other malignancies in primary Sjögren's syndrome: a cohort study on cancer incidence and lymphoma predictors.

OBJECTIVES: To assess the risk of lymphoproliferative disease or other malignancy (standardised incidence ratios (SIRs)), in patients with primary Sjögren's syndrome according to the American-European Consensus Criteria (AECC), compared with patients with sicca syndrome (non-AECC) and the background population. To identify predictors of malignancy and describe lymphoma types and survival probabilities. METHODS: A linked register study using information from the Malmö Primary SS Register, Swedish Cancer Register, and Cause-of-Death Register for calculation of SIRs was carried out. Detected lymphomas were reclassified according to the WHO classification. Cox regression analysis was used to study the predictive value of clinical, laboratory, and histological findings at the time of diagnosis. RESULTS: 507 patients with a median follow up of 8 years (range 1 month to 19 years) were included. SIRs (95% confidence interval (CI)) for malignancies in total and for non-Hodgkin's lymphomas (NHL) were 1.42 (0.98 to 2.00) and 15.57 (7.77 to 27.85), respectively, in those fulfilling the AECC (n = 286). In non-AECC sicca patients (n = 221) SIR for malignancy of any kind was 0.77 (0.41 to 1.32); no lymphoproliferative neoplasms were detected. Significant predictors of lymphoproliferative disease were purpura/skin vasculitis (hazard ratio (HR) = 4.64, 95% CI 1.13 to 16.45), low complement factor C3 (HR = 6.18, 95% CI 1.57 to 24.22), low C4 (HR = 9.49, 95% CI 1.94 to 46.54), CD4+ T lymphocytopenia (HR = 8.14, 95% CI 2.10 to 31.53), and a low CD4+/CD8+ T cell ratio < or = 0.8 (HR = 10.92, 95% CI 2.80 to 41.83). 7/12 (58%) NHLs were diffuse large B cell lymphomas. CONCLUSION: A 16-fold increased risk for development of NHL was found. CD4+ T lymphocytopenia is an additional strong risk factor for developing lymphoma.

Immunohistochemistry of the B-cell component in lower lip salivary glands of Sjögren's syndrome and healthy subjects.

Serial sections of lower lip salivary gland (LSG) biopsies were examined by immunohistochemistry, using a battery of B- and partly T-related antibodies (CD5, CD20, CD21, CD27, CD38, CD45RO, CD79a, Bcl-2 and Bcl-6) in different groups of subjects: healthy controls and clinically verified smoking or nonsmoking cases of primary Sjögren's syndrome (SS). The purpose was to characterize the B-cell pattern of the lymphocytic foci and of the tiny perivascular infiltrates preceding the development of foci. Hyperplastic tonsil was used as stain control. In normal LSG, widely dispersed CD38+ and CD79a+ as well as some CD5+ cells are a normal constituent, with lack of staining with the other antibodies. In SS/LSG, the lymphocytic foci showed staining with all the antibodies, with variable degrees of overlapping or nonoverlapping. In SS/LSG of nonsmokers, CD20+ B cells make up a prominent part of the fully developed periductal lymphocytic foci, not overlapping with CD45RO. Also, CD20+ B cells did not overlap in the infiltrates with colocalized CD27+/CD38+ cells. CD20+ B cells and CD45RO+ T cells also occur as minute infiltrates perivascularly in areas of no foci in SS/LSG as well as in SS smokers lacking the typical foci. Smokers lack foci, but tiny infiltrates express CD20 as well CD45R0. Our findings suggest that CD20+ B cells and CD45RO+ T cells are early immigrants in the LSG of SS of smokers as well as nonsmokers and that another subgroup of CD27+/CD38+ B cells gradually mix with the first two to form the characteristic foci in SS/LSG. The simultaneous demonstration of CD20+ and CD27+ B cells in SS/LSG may constitute a significant diagnostic tool. Further, the findings suggest that the early immigrating lymphocytes may have been primed at a site remote from the glands before arriving via the blood to the gland tissue.

Enhanced DNA-dependent protein kinase activity in Sjögren's syndrome B cells.

OBJECTIVE: To examine the stress response, including the role of DNA-dependent protein kinase (DNA-PK), in B cells from Sjögren's syndrome (SS) patients. METHODS: B-cell lines were exposed to gamma radiation and then postincubated to allow inducible stress functions to develop. The magnitude of the DNA damage response was monitored with respect to DNA-PK phosphorylation of a p53 peptide, defence protein levels (Ku, DNA-PK catalytic subunit, ATM, p21 and p53) and flow cytometric determination of cell cycle phases and apoptosis. RESULTS: B cells from SS patients, compared with healthy controls, displayed enhancement of two stress functions in undamaged cells: DNA-PK kinase activity and apoptosis. In addition, SS showed enhanced cell cycle arrest in gamma-irradiated cells. CONCLUSIONS: Strong kinase activity of DNA-PK, functioning not only in a DNA damage response but also in immunoglobulin gene rearrangement, may be an important component of the heightened stress response displayed by SS cells. In combination with recent reports, our data indicate that constitutional hyper-reactivity to danger signals is a basic pathogenetic factor in SS.

Enhanced DNA damage-induced p53 peptide phosphorylation and cell-cycle arrest in Sjögren's syndrome cells.

BACKGROUND: Cells from primary Sjögren's syndrome (SS) patients have been reported to show alterations in DNA repair and p53 expression. The DNA-dependent protein kinase (DNA-PK) autoantigen may be involved in both of these alterations in relation to cellular DNA damage responses. We conducted this study of cell-cycle kinetics and p53 to find additional evidence for an abnormal stress response role in the pathogenesis of SS. DESIGN: DNA-dependent protein kinase activity, p53 peptide phosphorylation and p53 protein levels were determined in gamma-irradiated long-term T lymphocyte cultures. Cell-cycle progression of peripheral blood mononuclear cells was analysed with flow cytometry. RESULTS: No significant differences in the DNA-PK activities or p53 protein levels appeared between the SS patients and the healthy individuals. However, patients with the SS hallmark Ro/SS-A and La/SS-B autoantibodies showed enhancement of both p53 peptide phosphorylation (P = 0.036) and G1 cell-cycle arrest (P = 0.015) in response to gamma radiation. CONCLUSIONS: Sjögren's syndrome cells express an enhanced G1 checkpoint function which may be mediated partly by p53 phosphorylation, suggesting that an abnormal stress response in SS is of relevance for the development of this autoimmune disease.

Ku protein and DNA strand breaks in lip glands of normal and primary Sjögren's syndrome subjects: lack of correlation with apoptosis.

UNLABELLED: The aim was to examine tissue expression of Ku protein in lower lip salivary gland (LSG) biopsies from cases of primary Sjögren's syndrome (SS) and from normal subjects. METHODS: immunohistochemistry was used with antibodies to Ku70/86 and also Ki67, PCNA and p53. In addition, the Klenow method was applied in order to detect evidence of apoptosis. Sections of hyperplastic tonsil served as additional controls. RESULTS: in normal controls, LSG acinar cells stained negatively whereas LSG excretory duct cell nuclei stained positively with Ku and Klenow and occasionally with PCNA but negatively with Ki67 and p53. In LSG focal sialadenitis of SS cases, some lymphocytic cells showed staining with Ku, Ki67, PCNA, Klenow and p53. In addition to duct cell Ku and Klenow as well as PCNA staining which was not much different from normals, a few ductal epithelial and also mononuclear cells stained with p53. In focal sialadenitis, some acinar cells showed staining with PCNA as well as with Klenow. CONCLUSIONS: our findings in LSG biopsies of SS cases added little to an increased understanding about the pathogenetic mechanisms in the development of focal sialadenitis in SS. However, in normal LSG, ductal epithelial but not acinar cells seem to express a constitutively specific Ku protein and Klenow profile, suggestive of DNA strand breaks but not clearly associated with ongoing apoptotic events. It may reflect an enhanced stress response, which may be pathogenetically important in the early events of focal sialadenitis development in primary Sjögren's syndrome.

Ku protein in human T and B lymphocytes: full length functional form and signs of degradation.

DNA-dependent protein kinase (DNA-PK) has been shown to take part in cell cycle regulatory signal transduction and in the repair of X-ray-induced DNA double-strand breaks. Functional DNA-PK is furthermore needed for the generation of antigen specificity during lymphocyte maturation. The Ku86 subunit of DNA-PK has been reported to exist in human B lymphocytes in a truncated form capable of binding to broken DNA but lacking the ability to activate the kinase function of DNA-PK. In the present work the Ku70 and Ku86 dimer proteins in T and B lymphocytes from human blood donors were analysed by immunoblotting and were observed apparently to be of full length. Also, nuclear protein extracted from B and non-B lymphocytes displayed DNA-dependent kinase activity. However, a minor fraction of Ku86 in lymphocytes was observed to be truncated with a molecular mass of approx. 70 kDa.

Laparoscopy reduces unnecessary appendicectomies and improves diagnosis in fertile women. A randomized study.

BACKGROUND: The aim of this study was to study the value of diagnostic laparoscopy prospectively in fertile women scheduled for acute appendectomy. METHODS: For this study, 110 women, with acute abdominal pain ages 15 to 47 years, in whom the surgeon had decided to perform an appendectomy, were randomized to either open appendectomy or diagnostic laparoscopy, then open appendectomy if necessary. RESULTS: Appendicitis was diagnosed in 66% of the women after open surgery, and in 73% after laparoscopy. During laparoscopy, was appendicitis misdiagnosed in only 7% of the women, from whom the appendix unnecessarily removed, whereas 34% in the open surgery group had a healthy appendix removed. No appendicitis was missed in the laparoscopic group. The relative risk of removing a healthy appendix in open surgery was 6.6 relative risk (range, 2-21 C.I.) as compared with laparoscopy. Among the women with a healthy appendix, a gynecologic diagnosis was found in 73% after laparoscopy, as compared with 17% after open surgery. CONCLUSIONS: Laparoscopy reduces unnecessary appendectomies and improves diagnosis in fertile women.

Effects of topical budesonide treatment on glucocorticoid receptor mRNA down-regulation and cytokine patterns in nasal polyps.

UNLABELLED: The effects of a topically applied corticosteroid, budesonide, on the expression of glucocorticoid receptor (GR) mRNA and regulation of pro-inflammatory cytokine patterns in patients with nasal polyps were evaluated. All patients were eligible for surgical polypectomy, and a majority of them had been treated with nasal steroids. Patients were given 400 microg b.i.d. (group A, n = 11), 200 microg b.i.d. (group B, n = 10), or no treatment (group C, n = 15) during two months before polypectomy. Morning serum cortisol was analyzed on the day of surgery. Surgically removed polyps were taken for analysis of GR mRNA expression by solution hybridization. Remaining tissue was cryostat-sectioned, whereafter quantification of the cytokines interleukin 1beta, interleukin 2, interleukin 4, interleukin 5, interleukin 6, interleukin 10, tumor necrosis factor alpha, and interferon gamma was made by immunohistochemistry and digitized image analysis. No significant differences among the three groups were found for any of the parameters investigated. CONCLUSION: nasal polyps do not respond with down-regulation of GR mRNA or cytokines following topical corticosteroid treatment. The proposed corticosteroid resistance may be inherent, or induced by a change of local tissue bioavailability.

Is cellobiose dehydrogenase from Phanerochaete chrysosporium a lignin degrading enzyme?

Cellobiose dehydrogenase (CDH) is an extracellular redox enzyme of ping-pong type, i.e. it has separate oxidative and reductive half reactions. Several wood degrading fungi produce CDH, but the biological function of the enzyme is not known with certainty. It can, however, indirectly generate hydroxyl radicals by reducing Fe(3+) to Fe(2+) and O2 to H2O2. Hydroxyl radicals are then generated by a Fenton type reaction and they can react with various wood compounds, including lignin. In this work we study the effect of CDH on a non-phenolic lignin model compound (3,4-dimethoxyphenyl glycol). The results indicate that CDH can affect lignins in three important ways. (1) It breaks beta-ethers; (2) it demethoxylates aromatic structures in lignins; (3) it introduces hydroxyl groups in non-phenolic lignins. The gamma-irradiated model compound gave a similar pattern of products as the CDH treated model compound, when the samples were analyzed by HPLC, suggesting that hydroxyl radicals are the active component of the CDH system.

Polygalacturonase is the key component in enzymatic retting of flax.

Seven commercial enzyme mixtures were tested for their ability to perform retting of flax (i.e. to separate flax fibers by partly removal of middle lamella) and were assayed for hydrolysis of xylan, cellulose and four kinds of pectin. The only activity that showed correlation to the ability to perform retting was the degradation of low esterfied pectin. A purified Aspergillus niger polygalacturonase was also shown to be able to perform retting. From this data it is hypothesized that degradation of the smooth regions (i.e. non-methylated polygalacturonase) in the middle lamella pectin is the most important step in enzymatic retting.

Do the extracellular enzymes cellobiose dehydrogenase and manganese peroxidase form a pathway in lignin biodegradation?

The extracellular enzyme manganese peroxidase is believed to degrade lignin by a hydrogen peroxide-dependent oxidation of Mn(II) to the reactive species Mn(III) that attacks the lignin. However, Mn(III) is not able to directly oxidise the non-phenolic lignin structures that predominate in native lignin. We show here that pretreatment of a non-phenolic lignin model compound with another extracellular fungal enzyme, cellobiose dehydrogenase, allows the manganese peroxidase system to oxidise this molecule. The mechanism behind this effect is demethoxylation and/or hydroxylation, i.e. conversion of a non-phenolic structure to a phenolic one, mediated by hydroxyl radicals generated by cellobiose dehydrogenase. This suggests that cellobiose dehydrogenase and manganese peroxidase may act in an extracellular pathway in fungal lignin biodegradation. Analytical techniques used in this paper are reverse-phase high-pressure liquid chromatography, gas chromatography connected to mass spectroscopy and UV-visible spectroscopy.

Antibodies to CD4 in primary Sjögren's syndrome.

OBJECTIVE: The purpose of this study was to examine whether antibodies against CD4 are present in patients with primary Sjögren's syndrome, and to explore the possible correlation between these antibodies and the CD4+ T lymphocyte depletion that is seen in some Sjögren patients. METHODS: Sera from 214 patients with primary Sjögren's syndrome, 154 healthy blood donors, 38 age- and sex-matched controls without autoimmune disease, and 77 HIV-1-seropositive individuals were analysed by an enzyme-linked immunosorbent assay (ELISA) using recombinant soluble CD4 as the antigen. RESULTS: Anti-CD4 antibodies were observed more frequently in patients with Sjögren's syndrome (12.6%) as compared with the control groups (0.6%) (P < 0.001), and at a level similar to that seen among the HIV-1 patients (13.0%). However, no correlation was found between the presence of anti-CD4 antibodies and CD4+ T lymphocytopenia in the Sjögren patients. CONCLUSION: This is the first study that shows anti-CD4 antibodies in patients with primary Sjögren's syndrome. The significance of these antibodies in the immunopathogenesis of Sjögren's syndrome remains to be determined.

A critical review of cellobiose dehydrogenases.

Cellobiose dehydrogenase (CDH) is an extracellular enzyme produced by various wood-degrading fungi. It oxidizes soluble cellodextrins, mannodextrins and lactose efficiently to their corresponding lactones by a ping-pong mechanism using a wide spectrum of electron acceptors including quinones, phenoxyradicals, Fe(3+), Cu(2+) and triiodide ion. Monosaccharides, maltose and molecular oxygen are poor substrates. CDH that adsorbs strongly and specifically to cellulose carries two prosthetic groups; namely, an FAD and a heme in two different domains that can be separated after limited proteolysis. The FAD-containing fragment carries all known catalytic and cellulose binding properties. One-electron acceptors, like ferricyanide, cytochrome c and phenoxy radicals, are, however, reduced more slowly by the FAD-fragment than by the intact enzyme, suggesting that the function of the heme group is to facilitate one-electron transfer. Non-heme forms of CDH have been found in the culture filtrate of some fungi (probably due to the action of fungal proteases) and were for a long time believed to represent a separate enzyme (cellobiose:quinone oxidoreductase, CBQ). The amino acid sequence of CDH has been determined and no significant homology with other proteins was detected for the heme domain. The FAD-domain sequence belongs to the GMC oxidoreductase family that includes, among others, Aspergillus niger glucose oxidase. The homology is most distinct in regions that correspond to the FAD-binding domain in glucose oxidase. A cellulose-binding domain of the fungal type is present in CDH from Myceliophtore thermophila (Sporotrichum thermophile), but in others an internal sequence rich in aromatic amino acid residues has been suggested to be responsible for the cellulose binding. The biological function of CDH is not fully understood, but recent results support a hydroxyl radical-generating mechanism whereby the radical can degrade and modify cellulose, hemicellulose and lignin. CDH has found technical use in highly selective amperometric biosensors and several other applications have been suggested.

A new scaffold for binding haem in the cytochrome domain of the extracellular flavocytochrome cellobiose dehydrogenase.

BACKGROUND: The fungal oxidoreductase cellobiose dehydrogenase (CDH) degrades both lignin and cellulose, and is the only known extracellular flavocytochrome. This haemoflavoenzyme has a multidomain organisation with a b-type cytochrome domain linked to a large flavodehydrogenase domain. The two domains can be separated proteolytically to yield a functional cytochrome and a flavodehydrogenase. Here, we report the crystal structure of the cytochrome domain of CDH. RESULTS: The crystal structure of the b-type cytochrome domain of CDH from the wood-degrading fungus Phanerochaete chrysosporium has been determined at 1.9 A resolution using multiple isomorphous replacement including anomalous scattering information. Three models of the cytochrome have been refined: the in vitro prepared cytochrome in its redox-inactive state (pH 7.5) and redox-active state (pH 4.6), as well as the naturally occurring cytochrome fragment. CONCLUSIONS: The 190-residue long cytochrome domain of CDH folds as a beta sandwich with the topology of the antibody Fab V(H) domain. The haem iron is ligated by Met65 and His163, which confirms previous results from spectroscopic studies. This is only the second example of a b-type cytochrome with this ligation, the first being cytochrome b(562). The haem-propionate groups are surface exposed and, therefore, might play a role in the association between the cytochrome and flavoprotein domain, and in interdomain electron transfer. There are no large differences in overall structure of the cytochrome at redox-active pH as compared with the inactive form, which excludes the possibility that pH-dependent redox inactivation results from partial denaturation. From the electron-density map of the naturally occurring cytochrome, we conclude that it corresponds to the proteolytically prepared cytochrome domain.

Women endurance runners with menstrual dysfunction have prolonged interruption of training due to injury.

Strenuous exercise by women is associated with menstrual dysfunction, eating disorders and osteoporosis. Intensive training may also increase the susceptibility to infections. In this study, we investigated whether menstrual dysfunction was related to musculoskeletal injuries and/or upper respiratory tract infections in women middle/long-distance runners. A questionnaire was mailed to 127 Swedish female runners of whom 75% answered. This retrospective study showed a higher frequency of menstrual disorders (25%) in runners than in the general population. Furthermore, almost half of the athletes (46%) were classified as at risk of developing eating disorders. Women athletes with menstrual dysfunction were found to have had a longer interruption of training due to musculoskeletal injuries than those with regular cycles (34.1 +/- 3.0 vs. 9.0 +/- 9. 4 days, p < 0.05). However, no relation was found between susceptibility to infections and menstrual status.