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81.
OBJECTIVE: To study the autoimmune response in mothers of children with isolated congenital heart block (CHB) and heart block (HB) diagnosed postnatally. METHODS: We reviewed the Finnish hospital registries for patients born between 1950 and 2000 and diagnosed with isolated HB before the age of 16 years. Clinical data and sera for the determination of autoantibodies were available from 67 mothers of children with CHB and from 37 mothers of children with postnatally diagnosed HB 9.9 years and 22.6 years (mean) after the index delivery, respectively. Maternal antibodies to 52 kDa and 60 kDa SSA and 48 kDa SSB were determined by time-resolved fluoroimmunoassay (TR-FIA) and by immunoblotting. Other marker antibodies for connective tissue diseases (CTD) were determined by immunoblot and/or by immunofluorescence. The control group comprised 136 mothers with primary Sj?gren's syndrome (SS), systemic lupus erythematosus (SLE), or other CTD with healthy children. RESULTS: Sixty of our 67 mothers (90%) of children with CHB had antibodies to SSA or SSB by the methods initially used in this study. When retests and tests performed previously were taken into account, only 3 (4%) of the 67 mothers did not have any autoantibodies. Two (3%) of the 67 mothers had antibodies to dsDNA and one (1%) each to Jo-1/HRS, RNP-70 kDa, and histone proteins. Of 37 mothers of children with postnatally diagnosed HB, only 3 (8%) had any autoantibodies. Increased risk of having a child with CHB was indicated by maternal primary SS and high levels of anti-SSA and anti-SSB by all assays, whereas low risk was indicated by maternal SLE or other CTD and undetectable or low levels of the antibodies. No single anti-SSA or anti-SSB test was clearly superior to others, but in general, immunoblots were more specific than TR-FIA. CONCLUSION: Maternal autoimmune disorder is almost always associated with CHB but only rarely with postnatally diagnosed HB. Anti-SSA and anti-SSB are marker antibodies for mothers of children with CHB, and an increased risk of having an affected child is indicated by maternal primary SS and high titer antibodies to SSA and SSB.  相似文献   
82.
Several growth factors and cytokines are involved in regulation of the immediate repair of gastrointestinal mucosa, a process also called restitution. Few data exist on the effect of inflammation on this process using an explant model, where the folded basal lamina is included. The aim of the present study was to investigate the effect of simulated inflammation on restitution and on concomitant proliferation and apoptosis in isolated guinea pig gastric mucosa. Paired gastric mucosae were mounted in Ussing chambers (37 degrees C) and a superficial injury was induced (1.25 M NaCl/5 min) followed by a 4-hr restitution (pH 7.3-7.5). During perfusion, simulated inflammation was induced (with 0.5 or 5.0 ng/ml IL-1beta or with activated polymorphonuclear [PMN] cells). The PI (proliferative index) and AI (apoptotic index) are expressed as the number of Mib-1- or Bax-immunopositive cells per 300 foveolar cells, respectively. The mean recovery of electrophysiological resistance of tissues (R) after injury and exposure to serosal IL-1beta during restitution was 95.2 +/- 5.3% (mean +/- SD), whereas the value for control tissues was 89.6 +/- 6.9% (P = 0.016; N = 9). The mean recovery of R in tissues exposured to activated serosal PMN cells during restitution was 97.6 +/- 2.7%, whereas the value for unexposed control tissues was 93.8 +/- 2.9 (P = 0.004; N = 9). The enhancing effect of PMN cells was partially eliminated by serosal anti-ICAM, whereas serosal cytochalasin D abolished the process completely. The PI of tissues exposed to serosal PMN cells was 34.6 +/- 17.3, whereas the value for unexposed controls was 24.7 +/- 15.5 (P = 0.04; N = 5). The corresponding AI values were 17.0 +/- 2.8 and 12.0 +/- 5.7, respectively (NS; N = 4). Simulated inflammation either with serosal IL-1beta or with activated PMN cells enhances restitution and proliferation, whereas their effect on AI is only suggestive. Exogenous serosal anti-ICAM modulates restitution, whereas cytochalasin D abolishes it completely, suggesting that the structural signaling system including focal adhesions and cytoskeleton plays a significant role in the regulation of restitution.  相似文献   
83.
The steroidal module of the Athlete Biological Passport (ABP) aims to detect doping with endogenous steroids, e.g. testosterone (T), by longitudinally monitoring several biomarkers. These biomarkers are ratios combined into urinary concentrations of testosterone and metabolically related steroids. However, it is evident after 5 years of monitoring steroid passports that there are large variations in the steroid ratios complicating its interpretation. In this study, we used over 11000 urinary steroid profiles from Swedish and Norwegian athletes to determine both the inter‐ and intra‐individual variations of all steroids and ratios in the steroidal passport. Furthermore, we investigated if the inter‐individual variations could be associated with factors such as gender, type of sport, age, time of day, time of year, and if the urine was collected in or out of competition. We show that there are factors reported in today's doping tests that significantly affect the steroid profiles. The factors with the largest influence on the steroid profile were the type of sport classification that the athlete belonged to as well as whether the urine was collected in or out of competition. There were also significant differences based on what time of day and time of year the urine sample was collected. Whether these significant changes are relevant when longitudinally monitoring athletes in the steroidal module of the ABP should be evaluated further.  相似文献   
84.
Sialoadhesin (Sn, also known as Siglec‐1 and CD169) is a macrophage‐restricted cell surface receptor that is conserved across mammals. Sn is a member of the sialic acid‐binding IgG‐like lectin (Siglec) family of proteins characterized by affinity to specifically sialylated ligands, and under normal conditions is expressed on subsets of macrophages in secondary lymphoid tissues, such as lymph node and spleen. However, Sn‐positive macrophages can also be found in a variety of pathological conditions, including (autoimmune) inflammatory infiltrates and tumours. Sn has been shown to contribute to sialylated pathogen uptake, antigen presentation and lymphocyte proliferation, and to influence both immunity and tolerance. This review presents Sn as a macrophage‐specific marker of inflammation and immunoregulation with the potential to becoming an important biomarker for immunologically active macrophages and a target for therapy.  相似文献   
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86.
European Journal of Clinical Microbiology & Infectious Diseases - SARS-CoV-2 antibody assays are used for epidemiological studies and for the assessment of vaccine responses in highly...  相似文献   
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88.
We describe a rare case of ectopic Cushing’s syndrome that recurred 6 years after resection of a thymic neuroendocrine carcinoma. We discuss reasons for the differing clinical presentations, management, hormone profiles, as well as immunopathology. A 41-year-old male developed acute-onset Cushing’s syndrome. Clinical presentation and laboratory results were compatible with ectopic adrenocorticotropin hormone (ACTH) production. Computerized tomography (CT) showed a 3.6 cm thymic tumor which was successfully resected. Plasma ACTH (P-ACTH) normalized the first postoperative day. Histopathology demonstrated a well-differentiated neuroendocrine carcinoma with diffuse positivity for ACTH and focal corticotropin-releasing hormone (CRH) reactivity in a few scattered cells. The patient was in remission for 6 years. He then again presented with acute-onset Cushing’s syndrome. Fluorine-labeled dihydroxyphenylalanine (18F-DOPA) PET/CT showed local uptake in the mediastinum and he underwent repeat resection. However, P-ACTH remained increased (613 ng/l) and 24-h urinary cortisol was 36,720 nmol, suggesting incomplete tumor removal or metastatic spread. Metyrapone treatment was initiated but then withdrawn because the patient spontaneously recovered and cortisol metabolism gradually normalized within 3 weeks. Histopathology demonstrated a recurrent neuroendocrine carcinoma with the same features as the previous lesion but this time CRH was strongly positive in more numerous cells. Normalization of P-ACTH after primary surgery was compatible with ectopic ACTH production. However, the delayed fall in P-ACTH and serum cortisol is compatible with ectopic CRH production and stimulation of pituitary ACTH secretion, which gradually resolved. Although ectopic CRH production is very rare, the unusual dynamics illustrated here should raise the possibility of CRH production by a neuroendocrine tumor.  相似文献   
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