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PURPOSE: To investigate the association of potential risk factors for urinary tract infections (UTI) caused by E. coli producing ESBL vs. not producing ESBL in Iceland. METHODS: Observational, case-control study including a cohort of 27,747 patients (22,800 females, 4,947 males; 1207 cases, 26,540 controls) of all ages with UTI caused by E. coli in 2012 to 2021 at the clinical microbiology laboratory covering about 2/3 of the Icelandic population. Clinical patient data was obtained from three national databases. Logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs) as a measure of association between ESBL and exposure variables. RESULTS: The proportion of samples with ESBL-producing E. coli increased during the study period, from 2.6% in 2012 to 7.6% in 2021 (p < 0.001). ESBL-positive strains were detected in 1207 individuals (4.4%), 905 females (4.0%) and 302 males (6.1%). The following risk factors were identified: Male sex, higher age, institution type (hospital, nursing home), hospital-associated UTI, Charlson comorbidity index score ≥ 3, history of cystitis or hospitalization in the past year, and prescriptions for certain antibiotics or proton pump inhibitors (PPIs: OR 1.51) in the past half year. The antibiotic associated with the highest risk was ciprofloxacin (OR 2.45). CONCLUSION: The prevalence of UTIs caused by ESBL-producing E. coli has been increasing in Iceland. The strongest risk factors for ESBL production were previous antibiotic use, especially ciprofloxacin, and previous PPI use, both considered to be overprescribed. It is important to promote the prudent use of these drugs.
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Infecciones por Escherichia coli , Escherichia coli , Infecciones Urinarias , beta-Lactamasas , Humanos , Infecciones Urinarias/microbiología , Infecciones Urinarias/epidemiología , Infecciones Urinarias/tratamiento farmacológico , Islandia/epidemiología , Femenino , Masculino , Factores de Riesgo , Infecciones por Escherichia coli/epidemiología , Infecciones por Escherichia coli/microbiología , Infecciones por Escherichia coli/tratamiento farmacológico , beta-Lactamasas/metabolismo , Estudios de Casos y Controles , Escherichia coli/aislamiento & purificación , Escherichia coli/efectos de los fármacos , Escherichia coli/genética , Escherichia coli/enzimología , Anciano , Persona de Mediana Edad , Prevalencia , Adulto , Adolescente , Lactante , Preescolar , Niño , Adulto Joven , Anciano de 80 o más Años , Antibacterianos/uso terapéutico , Antibacterianos/farmacología , Recién NacidoRESUMEN
BackgroundLeptospirosis is a zoonotic disease caused by bacteria of the genus Leptospira. Humans are infected by exposure to animal urine or urine-contaminated environments. Although disease incidence is lower in Europe compared with tropical regions, there have been reports of an increase in leptospirosis cases since the 2000s in some European countries.AimWe aimed to describe the epidemiology of reported cases of leptospirosis in the European Union/European Economic Area (EU/EEA) during 2010-2021 and to identify potential changes in epidemiological patterns.MethodsWe ran a descriptive analysis of leptospirosis cases reported by EU/EEA countries to the European Centre for Disease Prevention and Control with disease during 2010-2021. We also analysed trends at EU/EEA and national level.ResultsDuring 2010-2021, 23 countries reported 12,180 confirmed leptospirosis cases corresponding to a mean annual notification rate of 0.24 cases per 100,000 population. Five countries (France, Germany, the Netherlands, Portugal and Romania) accounted for 79% of all reported cases. The highest notification rate was observed in Slovenia with 0.82 cases per 100,000 population. Overall, the notification rate increased by 5.0% per year from 2010 to 2021 (95% CI: 1.2-8.8%), although trends differed across countries.ConclusionThe notification rate of leptospirosis at EU/EEA level increased during 2010-2021 despite including the first 2 years of the COVID-19 pandemic and associated changes in population behaviours. Studies at (sub)national level would help broaden the understanding of differences at country-level and specificities in terms of exposure to Leptospira, as well as biases in diagnosis and reporting.
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Leptospira , Leptospirosis , Humanos , Pandemias , Europa (Continente)/epidemiología , Unión Europea , Rumanía , Leptospirosis/diagnóstico , Leptospirosis/epidemiologíaRESUMEN
From October 2022 through January 2023, nine patients with NDM-5/OXA-48-carbapenemase-producing Enterobacter hormaechei ST79 were detected in Denmark and subsequently one patient in Iceland. There were no nosocomial links between patients, but they had all been treated with dicloxacillin capsules. An NDM-5/OXA-48-carbapenemase-producing E. hormaechei ST79, identical to patient isolates, was cultured from the surface of dicloxacillin capsules in Denmark, strongly implicating them as the source of the outbreak. Special attention is required to detect the outbreak strain in the microbiology laboratory.
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Dicloxacilina , Brotes de Enfermedades , Humanos , Islandia/epidemiología , Dinamarca/epidemiologíaRESUMEN
OBJECTIVES: To estimate the frequency of iron deficiency (ID) and anaemia in blood donors in Iceland and the impact of serum ferritin (SF) testing policy change. BACKGROUND: Blood donations contribute to ID and/or anaemia in whole blood donors (WBD). SF may be used to monitor blood donor iron stores. MATERIALS AND METHODS: The study included WBD and new donors (ND) in the Icelandic Blood Bank in 1997-2019. SF was measured for ND and intermittently for WBD until October 2017, but thereafter for all WBD and ND at every visit. In January 2018, the SF threshold increased from 14 to 16 µg/L for ND and from 8 to 10 µg/L for WBD. RESULTS: The study included 85 370 SF results from 243 369 visits of 32 910 donors. Median SF was higher for males than females, both for ND (88.0 vs. 31.2 µg/L, p < 0.001) and WBD (before 2018: 43.0 vs. 22.0 µg/L, p < 0.001). After the policy change in 2018, median SF increased for both male WBD (to 45.2 µg/L, p < 0.001) and female WBD (to 25.7 µg/L, p < 0.001). ID (SF <15 µg/L) was present in 10.6% of female ND and 0.5% of male ND. After policy change, the proportion of WB donations associated with ID decreased for males (from 6.4% to 4.0%) and females (from 18.9% to 14.1%). ID anaemia was present at some time in 3.7% of female WBD and 1.2% of male WBD. CONCLUSION: This nationwide study showed that ID in WB donors is common, especially among females, but monitoring SF may improve donor management.
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Anemia Ferropénica , Anemia , Deficiencias de Hierro , Anemia Ferropénica/epidemiología , Donantes de Sangre , Femenino , Humanos , Islandia/epidemiología , Hierro , MasculinoRESUMEN
BACKGROUND AND OBJECTIVES: Revised Icelandic guidelines proposed a restrictive haemoglobin (Hb) threshold of 70 g/l for red blood cell (RBC) transfusions in general, but 100 g/l for malignancies/bone marrow suppression. Chronic lymphocytic leukaemia (CLL) is frequently complicated by anaemia. The objective was to investigate RBC transfusion practices in CLL. MATERIALS AND METHODS: This retrospective nation-wide study utilized an Icelandic registry of CLL patients diagnosed between 2003 and 2016. Medical records were reviewed and haemoglobin transfusion triggers compared for two periods: Earlier (2003-2012) and latter (2013-2017). RESULTS: Two hundred and thirteen patients were diagnosed with CLL over the period whereof 77 (36·2%) received RBC transfusion(s). Median time from diagnosis to first transfusion was 2·2 years. Higher age, Rai stage 3/4 at diagnosis (P < 0·05) and chemotherapy (P < 0·001) were associated with increased odds of transfusions. Shorter time to first transfusion correlated with higher age (P < 0·001) and Rai stage (P = 0·02) at diagnosis. The mean Hb trigger was 90·4 and 81·2 in the earlier and latter period respectively (P = 0·01). This difference in Hb triggers was most pronounced in patients without documented bone marrow involvement, or 80·5 g/l compared to 93·5 g/l (P = 0·004). The median time from diagnosis to transfusion was longer in the latter period (2·9 years vs. 1·6 years, P = 0·01). After RBC transfusions the survival decreased significantly (P < 0·001). CONCLUSION: One-third of CLL patients received RBC transfusions but few were heavily transfused. Older age, Rai stage, and chemotherapy predicted RBC use. The Hb transfusion trigger decreased over time while time to first RBC transfusion increased. RBC transfusions predict poor survival.
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Anemia/terapia , Transfusión de Eritrocitos/normas , Leucemia Linfocítica Crónica de Células B/complicaciones , Sistema de Registros , Adulto , Anciano , Anciano de 80 o más Años , Anemia/complicaciones , Femenino , Hemoglobinas , Humanos , Islandia , Masculino , Persona de Mediana Edad , Estudios RetrospectivosRESUMEN
BACKGROUND: Prior to infusion, cryopreserved autologous peripheral blood stem cell (auto-PBSC) grafts can either be thawed at the bedside or thawed and washed at the laboratory. At our center, manual washing of grafts prior to infusion was discontinued in April 2012 and bedside thawing was implemented. METHODS: This study compares the outcomes of two patient groups who received auto-PBSC either after post-thaw washing (n = 84) or bedside thawing (n = 83). RESULTS: No life-threatening infusion-related side effects were reported in either group. There was no significant difference in the mean CD34+ cells/kg dose of infused auto-PBSC in the two groups (p = 0.41), nor in the number of days to neutrophils > 0.5 × 10(9)/L (p = 0.14), days to platelets > 20 × 10(9)/L (p = 0.64), or days to platelets > 50 × 10(9)/L (p = 0.62) after transplant. There was also no difference in the number of days on total parenteral nutrition (p = 0.69), days on G-CSF therapy (p = 0.48), or days with fever (p = 0.73). Finally, there was no significant difference in the number of red cell units transfused (p = 0.32), or platelet units transfused (p = 0.94) after the transplant. One-hundred-day mortality was identical in the two groups (2.4%). CONCLUSION: Both thawing procedures are safe and result in acceptable engraftment and patient outcomes.
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Linfoma/terapia , Trasplante de Células Madre de Sangre Periférica/métodos , Adulto , Anciano , Antígenos CD34/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carboplatino/administración & dosificación , Criopreservación , Femenino , Congelación , Factor Estimulante de Colonias de Granulocitos/administración & dosificación , Células Madre Hematopoyéticas/citología , Humanos , Linfoma/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Trasplante Autólogo , Adulto JovenRESUMEN
BACKGROUND: Red blood cell (RBC) alloimmunization during pregnancy is still a major problem. Historically, anti-D antibodies are most likely to cause severe hemolysis, but other antibodies are also important. In Iceland, postnatal RhIg prophylaxis was implemented in 1969, universal RBC antibody screening was implemented in 1978, but antenatal RhIg prophylaxis is not yet routine. STUDY DESIGN AND METHODS: This nation-wide population study gathered data on alloimmunized pregnancies in Iceland between 1996 and 2015. Blood bank alloimmunization data were linked to Icelandic Medical Birth Registry data. RBC antibodies were classified as either clinically significant or clinically nonsignificant. RESULTS: In total, 912 positive antibody screens from 87,437 births were identified (1.04% prevalence). The most frequent antibodies were anti-M (19.4%), anti-E (19.0%), and anti-D (12.5%). Anti-D prevalence among D-negative mothers was 1.1%. Icelandic Medical Birth Registry data were available for 881 (96.6%) pregnancies. In the clinically significant group (n = 474), anti-E (27%) and anti-D (20%) were most common, whereas anti-M was most frequent (53%) in the clinically nonsignificant group (n = 407). Mothers in the clinically significant group were older, more often multigravidae, had more abortions and stillbirths, and had shorter gestational length. Newborns in the clinically significant group were less healthy, had lower weight and Apgar scores, and required more treatment. Among specificities in the clinically significant group, anti-D antibodies were most strongly associated with severe hemolysis. CONCLUSION: In this study, the prevalence of alloimmunization was similar to that in previous reports. Of all clinically significant antibodies, anti-D was most strongly associated with severe hemolysis, requiring phototherapy or exchange transfusions. Our data emphasize the importance of implementing an antenatal prophylactic RhIg program in Iceland in the near future.
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Incompatibilidad de Grupos Sanguíneos/epidemiología , Eritrocitos/inmunología , Complicaciones Hematológicas del Embarazo/sangre , Adulto , Incompatibilidad de Grupos Sanguíneos/inmunología , Recolección de Datos , Femenino , Hemólisis , Humanos , Islandia , Isoanticuerpos/sangre , Embarazo , Complicaciones Hematológicas del Embarazo/epidemiología , Complicaciones Hematológicas del Embarazo/inmunología , Sistema de Registros , Globulina Inmune rho(D)/sangre , Adulto JovenRESUMEN
Mantle cell lymphoma (MCL) and chronic lymphocytic leukemia (CLL) are mature CD5(+) B-cell malignancies with different biological/clinical characteristics. We recently reported an association between different prognostic subgroups of CLL (i.e., IGHV mutated and unmutated) and genomic methylation pattern. However, the relationship between DNA methylation and prognostic markers, such as the proliferation gene expression signature, has not been investigated in MCL. We applied high-resolution methylation microarrays (27,578 CpG sites) to assess the global DNA methylation profiles in 20 MCL (10 each with high/low proliferation signature) and 30 CLL (15 poor-prognostic IGHV unmutated subset #1 and 15 good-prognostic IGHV mutated subset #4) samples. Notably, MCL and each CLL subset displayed distinct genomic methylation profiles. After unsupervised hierarchical clustering, 17/20 MCL cases formed a cluster separate from CLL, while CLL subsets #1 and #4 formed subclusters. Surprisingly, few differentially methylated genes (n = 6) were identified between high vs. low proliferation MCL. In contrast, distinct methylation profiles were demonstrated for MCL and CLL. Importantly, certain functional classes of genes were preferentially methylated in either disease. For instance, developmental genes, in particular homeobox transcription factor genes (e.g., HLXB9, HOXA13), were more highly methylated in MCL, whereas apoptosis-related genes were enriched among targets methylated in CLL (e.g., CYFIP2, NR4A1). Results were validated using pyrosequencing, RQ-PCR and reexpression of specific genes. In summary, the methylation profile of MCL was homogeneous and no correlation with the proliferation signature was observed. Compared to CLL, however, marked differences were discovered such as the preferential methylation of homeobox genes in MCL.
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Metilación de ADN , ADN de Neoplasias/química , Regulación Neoplásica de la Expresión Génica , Leucemia Linfocítica Crónica de Células B/genética , Linfoma de Células del Manto/genética , Proteínas Reguladoras de la Apoptosis/genética , Azacitidina/análogos & derivados , Azacitidina/farmacología , División Celular , Línea Celular Tumoral/efectos de los fármacos , Línea Celular Tumoral/metabolismo , Islas de CpG/efectos de los fármacos , ADN (Citosina-5-)-Metiltransferasa 1 , ADN (Citosina-5-)-Metiltransferasas/antagonistas & inhibidores , Metilación de ADN/efectos de los fármacos , ADN de Neoplasias/genética , Decitabina , Femenino , Regulación Leucémica de la Expresión Génica , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Genes Homeobox , Genes de Inmunoglobulinas , Inhibidores de Histona Desacetilasas/farmacología , Humanos , Ácidos Hidroxámicos/farmacología , Cadenas Pesadas de Inmunoglobulina/genética , Leucemia Linfocítica Crónica de Células B/metabolismo , Linfoma de Células del Manto/metabolismo , Masculino , Proteínas de Neoplasias/genética , Análisis de Secuencia de ADN , Factores de Transcripción/genéticaRESUMEN
Somatic hypermutation (SHM) aberrantly targets proto-oncogenes in various non-Hodgkin's lymphoma. To test the association of SHM with transformation of follicular lymphoma (FL), we sequenced mutational hot spots in five proto-oncogenes (BCL6, PAX5, RHOH, MYC and PIM1) in 32 low-grade FL (lgFL) with follicular histology and 26 transformed FL (tFL) with diffuse large cell histology. No difference was detected in the fraction of specimens mutated (75% of lgFL and 77% of tFL) or in the mutation load (0.08 for lgFL vs. 0.06 mutations/100 bp/allele for tFL). Serial specimens were examined from 25 patients showing stable low-grade FL (slgFL; n=6) or a low-grade FL that later transformed into diffuse large cell lymphoma (tFL; n=19). slgFL and tFL patients accumulated similar numbers of mutations in the interval between biopsies. These data indicate that mutations attributable to aberrant SHM occur with similar frequency in low-grade and transformed FL; transformation is not associated with a higher rate of aberrant SHM. Moreover, the frequency of mutations attributable to aberrant SHM in tFL was significantly lower than that reported for de novo diffuse large B cell lymphoma, suggesting differing oncogenic mechanisms in transformed follicular lymphoma and de novo diffuse large B cell lymphoma.
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Transformación Celular Neoplásica , Linfoma Folicular/patología , Mutación , Humanos , Linfoma Folicular/genéticaRESUMEN
The BIOMED-2 PCR-based immunoglobulin gene rearrangement assays have quickly become the most commonly used laboratory method for detection of B-cell clonality. Therefore, the reliability of these assays under various conditions has become increasingly important. When studying paired cases of follicular lymphoma (FL) from individual patients, we used these assays to assess clonality in 40 formalin-fixed paraffin-embedded (FFPE) specimens from 19 patients diagnosed with FL. The assays of IGH rearrangement failed to give a clonal result in 26/40 (65%) specimens, while the IGK assays failed in only 3/40 (8%) specimens. The high failure rate of the IGH assays for this set of FFPE lymphomas cannot be explained by systematic problems with DNA extraction or amplification because the same IGH assays resulted in a low failure rate (3/32, 9%) for FFPE small lymphocytic lymphoma/chronic lymphocytic leukemia specimens and for fresh frozen FL specimens (1/6, 17%). Furthermore, in a second validation set of 13 FFPE follicular lymphoma the failure rate was 9/13 (69%). Therefore, the BIOMED-2 IGH assay did not perform well on FFPE follicular lymphoma specimens, and the IGK assay may be superior for assessing clonality when no fresh/frozen tissue is available.
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Linfocitos B/patología , Células Clonales/patología , Cadenas Pesadas de Inmunoglobulina/genética , Cadenas kappa de Inmunoglobulina/genética , Linfoma Folicular/patología , Errores Diagnósticos , Reordenamiento Génico , Humanos , Adhesión en Parafina , Reacción en Cadena de la PolimerasaRESUMEN
INTRODUCTION: Chronic lymphocytic leukemia (CLL) is characterized by the proliferation of monoclonal B-lymphocytes. MBL (monoclonal B-cell lymphocytosis) is considered a precursor state of the disease. Although CLL is incurable it is an indolent disorder and often detected incidentally on routine blood counts. Until now little information has been available on CLL in Iceland, including the incidence, diagnosis, symptoms or MBL precursor state. MATERIAL AND METHODS: This is a retrospective, descriptive study including CLL patients diagnosed in Iceland over the years 2003-2013. Registries of patients with a CLL diagnosis were obtained from the Icelandic Cancer Registry, Landspitali National University Hospital and the Medical Center in Mjódd. Medical records were reviewed for information on symptoms, diagnosis and treatment. Survival data and causes of death were obtained from national registries. RESULTS: The number of patients diagnosed with CLL over the study period was 161 (109 males, 52 females). The calculated incidence was 4.55/100,000, and the age-standardized incidence was 3.00/100,000. Mean age at diagnosis was 70.9 years (range 35-96 years). The Icelandic Cancer Registry lacked information on 28 patients (17.4%). The initial diagnosis of CLL was obtained exclusively with flow cytometry in 47.2% of cases. Symptoms were present at diagnosis in 67 of 151 patients (44.4%). One third of the group received chemotherapy and the average time to treatment was 1.3 years. Five-year survival was 70% and median survival was 9.4 years. Elevated lymphocyte counts (≥4,0x109/L) in peripheral blood prior (0.1 to 13.4 years) to diagnosis of CLL was identified in 85 of 99 CLL patients (85.9%). CONCLUSION: The incidence of CLL in Iceland is similar to other Western countries. The registration of CLL cases in the Icelandic Cancer Registry must be improved, especially in cases where diagnosis is based solely on flow cytometry. Elevated lymphocyte counts were present in a large proportion of cases prior to the diagnosis of CLL. KEY WORDS: Chronic lymphocytic leukemia, CLL, monoclonal B-cell lymphocytosis, MBL, incidence, diagnosis. Correspondence: Anna Margret Halldorsdottir, annamha@landspitali.is.
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Leucemia Linfocítica Crónica de Células B/epidemiología , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Islandia/epidemiología , Incidencia , Leucemia Linfocítica Crónica de Células B/diagnóstico , Leucemia Linfocítica Crónica de Células B/mortalidad , Leucemia Linfocítica Crónica de Células B/terapia , Masculino , Persona de Mediana Edad , Sistema de Registros , Estudios Retrospectivos , Factores de Riesgo , Análisis de Supervivencia , Factores de Tiempo , Resultado del TratamientoRESUMEN
INTRODUCTION: Hemolytic disease of the fetus and newborn (HDFN) is caused by the destruction of fetal red blood cells due to red cell antibodies produced by the mother. HDFN can cause fetal hydrops during pregnancy or neonatal jaundice after birth. Direct Antiglobulin Test (DAT) detects antibodies bound to red cells and is a valuable test aiding in the diagnosis of HDFN. In Iceland DAT is routinely performed on cord blood or newborn blood samples if the mother is Rhesus D negative or has non-A/B red cell alloantibodies. The aim of this study was to investigate the causes and consequences of positive DAT in newborns in Iceland over a period of eight years. MATERIAL AND METHODS: The study population was infants diagnosed with a positive DAT in the Blood Bank in Iceland in the years 2005-2012. Relevant data on the blood group and antibody status of mother and child, blood transfusion and DAT results were retrieved from the Blood Bank information system ProSang. Birth records provided information on birth weight, gestational age and phototherapy. Health records from the Children's Hospital provided information on the management and fate of the newborn. RESULTS: Over the study period 383 newborns had a positive DAT result at the Blood Bank. In 73.6% of cases the underlying cause was ABO blood group mismatch between mother and infant, in 20.4% of cases the mother had non-A/B red cell alloantibodies, in 3.9% both of above factors were present, while in 2.1% the cause was unclear. A total of 179 (47.6%) children had neonatal jaundice that required treatment, of which 167 (93.3%) only needed phototherapy. Eight infants required exchange transfusion, five of these had Rhesus antibodies and three ABO blood group mismatch. CONCLUSION: ABO blood group mismatch between mother and child was the most common cause for a positive DAT in neonates in Iceland in the years 2005-2012. Almost half of the neonates required treatment but usually phototherapy was sufficient. Rarely, blood transfusion or exchange transfusion was necessary in severe cases of ABO blood group mismatch or non-A/B red cell alloantibodies. KEY WORDS: Coombs test, Direct Antiglobulin Test (DAT), Hemolytic disease of the fetus and newborn (HDFN), ABO blood group mismatch, red cell alloantibodies, neonatal jaundice, exchange transfusion. Correspondence: Anna Margret Halldorsdottir, annamha@landspitali.is.
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Sistema del Grupo Sanguíneo ABO/inmunología , Bancos de Sangre , Prueba de Coombs , Eritroblastosis Fetal/diagnóstico , Eritrocitos/inmunología , Isoanticuerpos/sangre , Ictericia Neonatal/diagnóstico , Tamizaje Neonatal/métodos , Biomarcadores/sangre , Incompatibilidad de Grupos Sanguíneos/sangre , Incompatibilidad de Grupos Sanguíneos/diagnóstico , Incompatibilidad de Grupos Sanguíneos/inmunología , Transfusión Sanguínea , Eritroblastosis Fetal/sangre , Eritroblastosis Fetal/inmunología , Eritroblastosis Fetal/terapia , Sangre Fetal/inmunología , Prueba de Histocompatibilidad , Humanos , Recién Nacido , Ictericia Neonatal/sangre , Ictericia Neonatal/inmunología , Ictericia Neonatal/terapia , Fototerapia , Valor Predictivo de las Pruebas , Pronóstico , Factores de TiempoRESUMEN
Dermatan sulfate (DS) accelerates the inhibition of thrombin by heparin cofactor II (HCII). A hexasaccharide consisting of three l-iduronic acid 2-O-sulfate (IdoA2SO3)-->N-acetyl-D-galactosamine 4-O-sulfate (GalNAc4SO3) subunits was previously isolated from porcine skin DS and shown to bind HCII with high affinity. DS from porcine intestinal mucosa has a much lower content of this disaccharide but activates HCII with potency similar to that of porcine skin DS. Therefore, we sought to characterize oligosaccharides from porcine mucosal DS that interact with HCII. DS was partially depolymerized with chondroitinase ABC, and oligosaccharides containing 2-12 monosaccharide units were isolated. The oligosaccharides were then fractionated by anion-exchange and affinity chromatography on HCII-Sepharose, and the disaccharide compositions of selected fractions were determined. We found that the smallest oligosaccharides able to bind HCII were hexasaccharides. Oligosaccharides 6-12 units long that lacked uronic acid (UA)2SO3 but contained one or two GalNAc4,6SO3 residues bound, and binding was proportional to both oligosaccharide size and number of GalNAc4,6SO3 residues. Intact DS and bound dodecasaccharides contained predominantly IdoA but little D-glucuronic acid. Decasaccharides and dodecasaccharides containing one or two GalNAc4,6SO3 residues stimulated thrombin inhibition by HCII and prolonged the clotting time of normal but not HCII-depleted human plasma. These data support the hypothesis that modification of IdoA-->GalNAc4SO3 subunits in the DS polymer by either 2-O-sulfation of IdoA or 6-O-sulfation of GalNAc can generate molecules with HCII-binding sites and anticoagulant activity.
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Acetilgalactosamina/química , Dermatán Sulfato/metabolismo , Cofactor II de Heparina/metabolismo , Membrana Mucosa/química , Sulfatos/química , Animales , Secuencia de Carbohidratos , Condroitín Liasas/genética , Condroitín Liasas/metabolismo , Dermatán Sulfato/química , Cofactor II de Heparina/aislamiento & purificación , Humanos , Monosacáridos/química , Monosacáridos/aislamiento & purificación , Oligosacáridos/química , Oligosacáridos/metabolismo , Proteínas Recombinantes/metabolismo , Porcinos , Trombina/antagonistas & inhibidoresRESUMEN
Recent studies have described a spasmolytic polypeptide-expressing metaplastic cell lineage (SPEM) in the gastric fundic mucosa associated with both chronic H. pylori infection and gastric adenocarcinoma. We investigated the association of SPEM both with early gastric adenocarcinoma and in biopsies taken from patients prior to diagnosis of cancer. Two cohorts were examined. First, gastric resections from 29 patients with early gastric cancer were examined. Second, biopsies taken from 18 patients prior to the diagnosis of gastric cancer were compared with their respective resection specimens as well as with control biopsies from a cohort of 19 patients diagnosed with gastritis without subsequent development of cancer. The presence of SPEM and intestinal metaplasia (IM) adjacent to and distant from the cancer was compared and spasmolytic polypeptide (SP) immunostaining within dysplastic/cancerous cells was identified. SPEM was present adjacent to cancer in all early cancer cases where the tumor was located in the body or at the body/antrum junction, and was present in the body mucosa distant from the cancer in 76% of cases. Intestinal metaplasia was found adjacent to the tumor in 76% of cases and in body sections in 52% of resections. SP immunostaining was noted within cancer cells in 62% of tumors, and within dysplastic cells in 76% of resections where dysplasia was present. SPEM was present in 82% of the biopsies obtained prior to the diagnosis of cancer, compared with only 37% in the gastritis cohort. IM was present in only 57% of biopsies. In conclusion, SPEM is strongly associated with early gastric cancers and is observed in gastric biopsies prior to the development of cancer. In addition, early gastric cancers demonstrated a high incidence of SP expression. These results suggest that SPEM merits consideration as an important pre-neoplastic gastric lesion.