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1.
Transfusion ; 64(6): 998-1007, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38689458

RESUMEN

BACKGROUND: Current hemovigilance methods generally rely on survey data or administrative claims data utilizing billing and revenue codes, each of which has limitations. We used electronic health records (EHR) linked to blood bank data to comprehensively characterize red blood cell (RBC) utilization patterns and trends in three healthcare systems participating in the U.S. Food and Drug Administration Center for Biologics Evaluation and Research Biologics Effectiveness and Safety (BEST) initiative. METHODS: We used Information Standard for Blood and Transplant (ISBT) 128 codes linked to EHR from three healthcare systems data sources to identify and quantify RBC-transfused individuals, RBC transfusion episodes, transfused RBC units, and processing methods per year during 2012-2018. RESULTS: There were 577,822 RBC units transfused among 112,705 patients comprising 345,373 transfusion episodes between 2012 and 2018. Utilization in terms of RBC units and patients increased slightly in one and decreased slightly in the other two healthcare facilities. About 90% of RBC-transfused patients had 1 (~46%) or 2-5 (~42%)transfusion episodes in 2018. Among the small proportion of patients with ≥12 transfusion episodes per year, approximately 60% of episodes included only one RBC unit. All facilities used leukocyte-reduced RBCs during the study period whereas irradiated RBC utilization patterns differed across facilities. DISCUSSION: ISBT 128 codes and EHRs were used to observe patterns of RBC transfusion and modification methods at the unit level and patient level in three healthcare systems participating in the BEST initiative. This study shows that the ISBT 128 coding system in an EHR environment provides a feasible source for hemovigilance activities.


Asunto(s)
Registros Electrónicos de Salud , Transfusión de Eritrocitos , Humanos , Femenino , Masculino , Persona de Mediana Edad , Adulto , Estados Unidos , Eritrocitos , Anciano , Productos Biológicos/uso terapéutico , Bancos de Sangre/normas , Bancos de Sangre/estadística & datos numéricos , Adolescente
2.
Transfusion ; 61(3): 960-967, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33638187

RESUMEN

BACKGROUND: A 30-year-old man underwent double umbilical cord blood transplantation (UCBT) for acute myeloid leukemia (AML) with reduced intensity conditioning. The cords had identical HLA types and were each a 5/6 match to the patient. Following transplantation, cord 2 initially dominated all tested cell populations. At day +306, we observed an unusual reversal of dominance chimerism pattern in which cord 1 instead dominated all tested populations. STUDY DESIGN & METHODS: Polymerase chain reaction (PCR)-based short tandem repeat (STR) assays were performed on the peripheral blood and bone marrow samples. The white blood cell (WBC) populations from the peripheral blood were manipulated for testing to create subpopulations enriched for CD3, CD33, and CD56. RESULTS: Chimerism studies on day +77 showed the following: cord 1: 44%-CD3; 0%-CD33; 16%-CD56; cord 2: 56%-CD3; 100%-CD33; 84%-CD56. Cord 2 initially dominated in all tested cell populations. Chimerism studies performed on post-transplantation day +306 uncovered a reversal of dominance chimerism pattern in which cord 1 now dominated in all cell populations (cord 1: 82%-CD3; >95%-CD33; 67%-CD56; cord 2: 18%-CD3; <5%-CD33; 33%-CD56). Between days +127 and +244, the patient's blood type shifted from B Rh-positive to A Rh-negative. CONCLUSION: The change in the patient's blood type identified a late reversal of dominance chimerism pattern. This is a rare occurrence, previously cited only once, which is inconsistent with published data that early high CD3 counts and unseparated bone marrow chimerism predominance at day +100 predict long-term cord dominance in double UCBT in the vast majority of cases.


Asunto(s)
Quimerismo , Trasplante de Células Madre de Sangre del Cordón Umbilical , Leucemia Mieloide Aguda/sangre , Leucemia Mieloide Aguda/terapia , Leucocitos/metabolismo , Adulto , Tipificación y Pruebas Cruzadas Sanguíneas , Médula Ósea/metabolismo , Complejo CD3/sangre , Complejo CD3/genética , Antígeno CD56/sangre , Antígeno CD56/genética , Humanos , Leucemia Mieloide Aguda/genética , Masculino , Reacción en Cadena de la Polimerasa , Lectina 3 Similar a Ig de Unión al Ácido Siálico/sangre , Lectina 3 Similar a Ig de Unión al Ácido Siálico/genética
3.
J Clin Apher ; 31(6): 529-534, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26762291

RESUMEN

PURPOSE: Hematopoietic Progenitor Cell (HPC) collection by apheresis is performed in patients and donors to obtain HPCs for transplantation. Although studies have shown these procedures to be safe, successful collection cannot be performed without establishment of venous access. This project's objective was to ascertain the current practices of donor vein assessment and central venous catheter (CVC) usage. METHODS: The American Society for Apheresis (ASFA) HPC subcommittee created an electronic survey about precollection vein assessment and line placement, care, and removal in autologous and allogeneic donors. It was distributed to >5,000 possible participants, with one response analyzed per institution. RESULTS: One hundred centers performing autologous and/or allogeneic procedures provided adequate responses for analysis. Donor vein assessment is most often performed by apheresis staff more than 1 week prior to collection. For patients with questionable access, the next step performed most often is secondary assessment for autologous procedures and CVC placement for allogeneic procedures. Most centers use interventional radiology to place CVCs in jugular veins on collection day with placement verification through electronic medical records. Verbal and written postinsertion CVC care instructions are routinely provided. The apheresis team frequently provides postinsertion CVC care for autologous patients. Heparin is used most often for CVC lock. When used, tissue plasminogen activator is usually instilled for up to 60 min. CONCLUSION: These data summarize the largest single survey of donor vein assessment at institutions performing HPC collections by apheresis. The variations identified in donor venous access practice warrant further investigation and consensus to establish best practices. J. Clin. Apheresis 31:529-534, 2016. © 2015 Wiley Periodicals, Inc.


Asunto(s)
Eliminación de Componentes Sanguíneos/métodos , Cateterismo Venoso Central/efectos adversos , Células Madre Hematopoyéticas/citología , Cateterismo Venoso Central/métodos , Fibrinolíticos/uso terapéutico , Encuestas Epidemiológicas , Humanos , Sociedades Médicas , Donantes de Tejidos , Venas/efectos de los fármacos , Venas/patología
4.
Nat Genet ; 34(4): 434-9, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12858176

RESUMEN

In cortisone reductase deficiency (CRD), activation of cortisone to cortisol does not occur, resulting in adrenocorticotropin-mediated androgen excess and a phenotype resembling polycystic ovary syndrome (PCOS; refs. 1,2). This suggests a defect in the gene HSD11B1 encoding 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1), a primary regulator of tissue-specific glucocorticoid bioavailability. We identified intronic mutations in HSD11B1 that resulted in reduced gene transcription in three individuals with CRD. In vivo, 11beta-HSD1 catalyzes the reduction of cortisone to cortisol whereas purified enzyme acts as a dehydrogenase converting cortisol to cortisone. Oxo-reductase activity can be regained using a NADPH-regeneration system and the cytosolic enzyme glucose-6-phosphate dehydrogenase. But the catalytic domain of 11beta-HSD1 faces into the lumen of the endoplasmic reticulum (ER; ref. 6). We hypothesized that endolumenal hexose-6-phosphate dehydrogenase (H6PDH) regenerates NADPH in the ER, thereby influencing directionality of 11beta-HSD1 activity. Mutations in exon 5 of H6PD in individuals with CRD attenuated or abolished H6PDH activity. These individuals have mutations in both HSD11B1 and H6PD in a triallelic digenic model of inheritance, resulting in low 11beta-HSD1 expression and ER NADPH generation with loss of 11beta-HSD1 oxo-reductase activity. CRD defines a new ER-specific redox potential and establishes H6PDH as a potential factor in the pathogenesis of PCOS.


Asunto(s)
Deshidrogenasas de Carbohidratos/genética , Cortisona Reductasa/deficiencia , Hidroxiesteroide Deshidrogenasas/genética , Mutación , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 2 , Secuencia de Aminoácidos , Secuencia de Bases , Deshidrogenasas de Carbohidratos/metabolismo , Estudios de Casos y Controles , Línea Celular , ADN Complementario/genética , Retículo Endoplásmico/metabolismo , Exones , Femenino , Humanos , Hidroxiesteroide Deshidrogenasas/metabolismo , Masculino , Datos de Secuencia Molecular , NADP/metabolismo , Oxidación-Reducción , Fenotipo , Síndrome del Ovario Poliquístico/etiología , Síndrome del Ovario Poliquístico/genética , Síndrome del Ovario Poliquístico/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Homología de Secuencia de Aminoácido , Transfección
5.
BMC Surg ; 12: 14, 2012 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-22817672

RESUMEN

BACKGROUND: Patients having arthroscopic shoulder surgery frequently experience periods of inadvertent hypothermia. This common perioperative problem has been linked to adverse patient outcomes such as myocardial ischaemia, surgical site infection and coagulopathy. International perioperative guidelines recommend patient warming, using a forced air warming device, and the use of warmed intraoperative irrigation solutions for the prevention of hypothermia in at-risk patient groups. This trial will investigate the effect of these interventions on patients' temperature, thermal comfort, and total recovery time. METHOD/DESIGN: The trial will employ a randomised 2 x 2 factorial design. Eligible patients will be stratified by anaesthetist and block randomised into one of four groups: Group one will receive preoperative warming with a forced air warming device; group two will receive warmed intraoperative irrigation solutions; group three will receive both preoperative warming and warmed intraoperative irrigation solutions; and group four will receive neither intervention. Participants in all four groups will receive active intraoperative warming with a forced air warming device. The primary outcome measures are postoperative temperature, thermal comfort, and total recovery time. Primary outcomes will undergo a two-way analysis of variance controlling for covariants such as operating room ambient temperature and volume of intraoperative irrigation solution. DISCUSSION: This trial is designed to confirm the effectiveness of these interventions at maintaining perioperative normothermia and to evaluate if this translates into improved patient outcomes. AUSTRALIAN NEW ZEALAND CLINICAL TRIALS REGISTRY NUMBER: ACTRN12610000591055.


Asunto(s)
Artroscopía , Hipotermia/prevención & control , Complicaciones Intraoperatorias/prevención & control , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Articulación del Hombro/cirugía , Procedimientos Quirúrgicos Electivos , Calor/uso terapéutico , Humanos , Cuidados Intraoperatorios , Cuidados Preoperatorios , Irrigación Terapéutica
6.
J Perianesth Nurs ; 27(1): 18-24, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22264617

RESUMEN

Preoperative forced-air warming is one way of preventing inadvertent perioperative hypothermia. There is scant evidence, however, on the best warming method or the acceptability of these methods to patients. This pilot study compared two warming protocols: one that commenced at maximum temperature and was titrated down as requested (A) and one that commenced at near body temperature and was titrated up as tolerated (B). A crossover design was used in which each participant (n=10) received both protocols sequentially. The mean device temperature and length of time spent at maximum settings were greater for protocol A (43°C±0°C vs 41°C±1°C, P=.003; and 60±0 vs 41.5±2.8 minutes, P=.004). There was no difference in thermal comfort scores, participant temperature, or sweating between the two protocols. When asked, participants preferred protocol A to B (70% to 30%). Starting at higher device settings appears the more favorable of the two approaches.


Asunto(s)
Fiebre , Hipotermia/prevención & control , Cuidados Preoperatorios , Estudios Cruzados , Humanos
7.
Am J Clin Pathol ; 158(2): 249-253, 2022 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-35403671

RESUMEN

OBJECTIVES: To determine if blood type is a risk factor for coronavirus disease 2019 (COVID-19) disease incidence and severity after correcting for ethnicity differences between novel infections and known ABO blood type frequency differences. METHODS: We performed a retrospective analysis on all severe acute respiratory system coronavirus 2 (SARS-CoV-2) infections and disease severity across two major testing sites in Colorado. We evaluated all individuals with a SARS-CoV-2 nucleic acid test (NAT) and a known blood type between March 1, 2020, and June 1, 2020. We then created a prediction algorithm based on the corrected blood types by ethnicity using data from the Colorado Department of Health and established blood types by ethnicity. We applied this prediction algorithm to all patients in our sample. RESULTS: Of 8,676 patients, 485 (5.6%) had a positive SARS-CoV-2 NAT test and 8,191 (94.4%) had a negative test. All patients had ABO blood types that mirrored the expected blood type distribution within the state of Colorado (P = .15, χ 2 statistic = 5.31). No differences in expected blood groups were present between ethnicity-adjusted SARS-CoV-2-negative and SARS-CoV-2-positive patients (χ 2 = 3.416313, P = .332). CONCLUSIONS: Blood type is not associated with COVID-19 disease incidence or severity after correcting for ethnicity differences in expected blood type frequencies.


Asunto(s)
COVID-19 , Sistema del Grupo Sanguíneo ABO , Etnicidad , Humanos , Incidencia , Estudios Retrospectivos , SARS-CoV-2
8.
Arch Pathol Lab Med ; 145(12): 1499-1504, 2021 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-33720316

RESUMEN

CONTEXT.­: ABO mistransfusions are rare and potentially fatal events. Protocols are required by regulatory agencies to minimize this risk to patients, but how these are applied in the context of massive transfusion protocols (MTPs) is not specifically defined. OBJECTIVE.­: To evaluate the approaches used by transfusion services for switching from universally compatible to patient ABO type-specific blood components during massive hemorrhage. DESIGN.­: We added 1 supplemental multiple-choice question to address the study objective to the 2019 College of American Pathologists proficiency test J-survey (J-A 2019). We also reviewed the available literature regarding this topic. RESULTS.­: A total of 881 laboratories responded to the supplemental question. Approximately 80% (704 of 881) reported a policy for ABO-type switching during an MTP. Policies varied considerably between responding laboratories, but most (384 of 704, 55%) required 2 ABO types to match before switching from universal to recipient-specific blood components. Additional safety measures used in a minority of these protocols included reaction strength criteria (103 of 704, 15%), on-call medical director approval (41 0f 704, 5.8%), universal red cell unit number limits (12 of 704, 1.7%), or the presence of a mixed field (3 of 704, 0.4%). CONCLUSIONS.­: This survey reveals that significant heterogeneity exists regarding the available approaches for ABO-type switching during an MTP. Specific expert guidance regarding this issue is very limited, and best practices have not yet been established or rigorously investigated.


Asunto(s)
Tipificación y Pruebas Cruzadas Sanguíneas , Transfusión Sanguínea , Transfusión de Componentes Sanguíneos , Hemorragia/etiología , Humanos , Encuestas y Cuestionarios
9.
Endocr Rev ; 25(5): 831-66, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15466942

RESUMEN

11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1) interconverts inactive cortisone and active cortisol. Although bidirectional, in vivo it is believed to function as a reductase generating active glucocorticoid at a prereceptor level, enhancing glucocorticoid receptor activation. In this review, we discuss both the genetic and enzymatic characterization of 11beta-HSD1, as well as describing its role in physiology and pathology in a tissue-specific manner. The molecular basis of cortisone reductase deficiency, the putative "11beta-HSD1 knockout state" in humans, has been defined and is caused by intronic mutations in HSD11B1 that decrease gene transcription together with mutations in hexose-6-phosphate dehydrogenase, an endoluminal enzyme that provides reduced nicotinamide-adenine dinucleotide phosphate as cofactor to 11beta-HSD1 to permit reductase activity. We speculate that hexose-6-phosphate dehydrogenase activity and therefore reduced nicotinamide-adenine dinucleotide phosphate supply may be crucial in determining the directionality of 11beta-HSD1 activity. Therapeutic inhibition of 11beta-HSD1 reductase activity in patients with obesity and the metabolic syndrome, as well as in glaucoma and osteoporosis, remains an exciting prospect.


Asunto(s)
11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/fisiología , Glucocorticoides/farmacología , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/antagonistas & inhibidores , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/química , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/genética , Secuencia de Aminoácidos , Animales , Deshidrogenasas de Carbohidratos/genética , Clonación Molecular , Cortisona Reductasa/deficiencia , Cortisona Reductasa/genética , Inhibidores Enzimáticos , Regulación Enzimológica de la Expresión Génica , Glaucoma/enzimología , Humanos , Hidrocortisona/metabolismo , Datos de Secuencia Molecular , Mutación , NADP/metabolismo , Obesidad/enzimología , Especificidad de Órganos , Osteoporosis/enzimología , Proteínas Recombinantes , Alineación de Secuencia , Especificidad por Sustrato , Transcripción Genética
10.
Methods Mol Biol ; 439: 35-52, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18370094

RESUMEN

With the completion of the human genome sequencing project in 2001, the identification of novel markers is rapidly gaining importance. It is increasingly recognized that SNPs (single nucleotide polymorphisms) are good markers for disease susceptibility. SNPs are DNA sequence variations that occur when a single nucleotide in the genome sequence is altered in at least 1 % of the population. SNPs may have no effect on cell function, but scientists believe that they could predispose people to disease or influence their response to a drug. This chapter describes the method of using fluorescent based sequencing to detect SNPs and mutations. Sequencing provides information on the type and location of the SNPs with high accuracy. Researchers will need to provide information on the area of the genome they wish to sequence to design primers to PCR amplify the specific region.


Asunto(s)
Mutación , Polimorfismo de Nucleótido Simple , Análisis de Secuencia de ADN/métodos , Secuencia de Bases , Cartilla de ADN
11.
J Clin Lipidol ; 10(2): 438-42, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27055976

RESUMEN

In individuals with familial hypercholesterolemia (FH) who are unable to reach a target low-density lipoprotein level on a drug regimen, lipoprotein apheresis (LA) may be the treatment of choice. Severe reactions involving clotting during LA are not well described in the literature. We report a case of a 63-year-old woman with FH and markedly elevated lipoprotein(a) (Lp[a]) levels who experienced such a reaction while undergoing LA with a dextran-sulfate cellulose column on the Kaneka MA-01 Liposorber system. Owing to the clotting as well as a blood pressure drop to <100 mm Hg systolic, the procedure was stopped early. Before her second procedure, she was given an increased loading dose of unfractionated heparin. She did not develop clotting during this second procedure. A growing body of literature on the role of Lp(a) in atherothrombotic complications and hemostasis supports a possible mechanism by which clotting in the instrument could occur during apheresis. Our patient's initial pretreatment Lp(a) was 3.5 times greater than the mean Lp(a) levels in patients with FH. This theory is consistent with our case in that the patient's Lp(a) levels progressively declined with each procedure, and she had no subsequent clotting.


Asunto(s)
Eliminación de Componentes Sanguíneos , Lipoproteína(a)/sangre , Trombosis , Femenino , Humanos , Hiperlipoproteinemia Tipo II/sangre , Hiperlipoproteinemia Tipo II/fisiopatología , Hiperlipoproteinemia Tipo II/terapia , Persona de Mediana Edad
12.
Am J Clin Pathol ; 146(2): 238-43, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27473742

RESUMEN

OBJECTIVES: To understand the worldwide scope of RBC crossmatching and issuing practices and measure efficiency using a novel quality indicator, the crossmatch/issue (C/I) ratio. METHODS: An electronic survey was disseminated to hospital transfusion services collecting details about RBC crossmatching and issuing practices. Respondents were asked to enumerate the number of RBCs crossmatched and issued at their institutions during the 2014 calendar year to calculate the C/I ratio. RESULTS: Fifty-two survey responses were received, mostly from North American transfusion services (28/52, 54%). The electronic crossmatch was the most common technique (n = 29), and most respondents performed the crossmatch at the time that an order for RBCs was received in the transfusion service (even if an order to issue the RBCs was not received). Data to calculate the C/I ratio were supplied by 22 respondents, and the mean ± SD was 1.30 ± 0.34. There was no difference in C/I ratios between services that use the electronic or serologic crossmatch techniques (P = .49). The ratio was the same at the four sites that crossmatch RBCs at the time of issue compared with the time of order receipt (mean ± SD, 1.11 ± 0.09 vs. 1.35 ± 0.36, respectively; P = .19). CONCLUSIONS: Electronic crossmatching is common, and the C/I ratio can be an indicator of efficiency.


Asunto(s)
Tipificación y Pruebas Cruzadas Sanguíneas/métodos , Transfusión de Eritrocitos , Sistemas de Registros Médicos Computarizados , Humanos , Garantía de la Calidad de Atención de Salud , Encuestas y Cuestionarios
13.
Lancet ; 363(9427): 2128-35, 2004 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-15220035

RESUMEN

BACKGROUND: Congenital adrenal hyperplasia with apparent combined P450C17 and P450C21 deficiency is associated with accumulation of steroid metabolites, indicating impaired activity of 17alpha-hydroxylase and 21-hydroxylase. However, no mutations have been reported in the CYP17 and CYP21 genes, which encode these P450 enzymes. Affected girls are born with ambiguous genitalia, but their circulating androgens are low, and virilisation does not progress. We aimed to investigate the underlying molecular basis of congenital adrenal hyperplasia with apparent combined P450C17 and P450C21 deficiency in affected children. METHODS: We did sequence analysis of the human gene encoding P450 oxidoreductase, an enzyme that is important in electron transfer from NADPH to P450C17 and P450C21. We studied two unrelated families with a total of three affected children and 100 healthy controls. Wild-type and mutant P450 oxidoreductase proteins were bacterially expressed, purified, and assayed for cytochrome c reductase activity. FINDINGS: We identified four mutations encoding single aminoacid changes in P450 oxidoreductase. All patients were compound heterozygotes, whereas their parents and an unaffected sibling harboured a mutation in only one allele. By contrast, no mutations were noted in the controls. Bacterial expression of recombinant mutant proteins revealed deficient or reduced enzyme activity. INTERPRETATION: Molecular pathogenesis of this form of congenital adrenal hyperplasia is caused by mutations in the gene encoding P450 oxidoreductase. Deficiency of this enzyme could suggest an alternative pathway in human androgen synthesis, present only in fetal life, which explains the combination of antenatal androgen excess and postnatal androgen deficiency.


Asunto(s)
Hiperplasia Suprarrenal Congénita/genética , Andrógenos/biosíntesis , Sistema Enzimático del Citocromo P-450/genética , Mutación , Adolescente , Hiperplasia Suprarrenal Congénita/metabolismo , Sustitución de Aminoácidos , Preescolar , Sistema Enzimático del Citocromo P-450/química , Femenino , Humanos , Masculino
14.
J Mol Endocrinol ; 34(3): 675-84, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15956339

RESUMEN

Two isozymes of 11 beta-hydroxysteroid dehydrogenase (11 beta-HSD) interconvert active cortisol and inactive cortisone. 11 beta-HSD2 (renal) acts only as a dehydrogenase, converting cortisol to cortisone. 11 beta-HSD1 (liver) is a bi-directional enzyme in cell homogenates, whereas in intact cells it typically displays oxo-reductase activity, generating cortisol from cortisone. We recently established that cortisone reductase deficiency is a digenic disease requiring mutations in both the gene encoding 11 beta-HSD1 and in the gene for a novel enzyme located within the lumen of the endoplasmic reticulum (ER), hexose-6-phosphate dehydrogenase (H6PDH). This latter enzyme generates NADPH, the co-factor required for oxo-reductase activity. Therefore, we hypothesized that H6PDH expression may be an important determinant of 11 beta-HSD1 oxo-reductase activity. Transient transfection of chinese hamster ovary (CHO) cells with 11 beta-HSD1 resulted in the appearance of both oxo-reductase and dehydrogenase activities in intact cells. Co-transfection of 11 beta-HSD1 with H6PDH increased oxo-reductase activity whilst virtually eliminating dehydrogenase activity. In contrast, H6PDH had no effect on reaction direction of 11 beta-HSD2, nor did the cytosolic enzyme, glucose-6-phosphate dehydrogenase (G6PD) affect 11 beta-HSD1 oxo-reductase activity. Conversely in HEK 293 cells stably transfected with 11 beta-HSD1 cDNA, transfection of an H6PDH siRNA reduced 11 beta-HSD1 oxo-reductase activity whilst simultaneously increasing 11 beta-HSD1 dehydrogenase activity. In human omental preadipocytes obtained from 15 females of variable body mass index (BMI), H6PDH mRNA levels positively correlated with 11 beta-HSD1 oxo-reductase activity, independent of 11 beta-HSD1 mRNA levels. H6PDH expression increased 5.3-fold across adipocyte differentiation (P < 0.05) and was associated with a switch from 11 beta-HSD1 dehydrogenase to oxo-reductase activity. In conclusion, H6PDH is a crucial determinant of 11 beta-HSD1 oxo-reductase activity in intact cells. Through its interaction with 11 beta-HSD1, H6PDH may represent a novel target in the pathogenesis and treatment of obesity.


Asunto(s)
11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/metabolismo , Deshidrogenasas de Carbohidratos/metabolismo , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/genética , Adulto , Animales , Secuencia de Bases , Western Blotting , Células CHO , Deshidrogenasas de Carbohidratos/genética , Cricetinae , Cartilla de ADN , Femenino , Humanos , Reacción en Cadena de la Polimerasa , ARN Mensajero/genética , ARN Interferente Pequeño/genética
15.
J Endocrinol ; 186(2): 251-71, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16079253

RESUMEN

Two isozymes of 11beta-hydroxysteroid dehydrogenase (11beta-HSD1 and 11beta-HSD2) catalyse the interconversion of hormonally active cortisol and inactive cortisone. The enzyme evolved from a metabolic pathway to a novel mechanism underpinning human disease with the elucidation of the role of the type 2 or 'kidney' isozyme and an inherited form of hypertension, 'apparent mineralocorticoid excess'. 'Cushing's disease of the kidney' arises because of a failure of 11beta-HSD2 to inactivate cortisol to cortisone resulting in cortisol-induced mineralocorticoid excess.Conversely, 11beta-HSD1 has been linked to human obesity and insulin resistance, but also to other diseases in which glucocorticoids have historically been implicated (osteoporosis, glaucoma). Here, the activation of cortisol from cortisone facilitates glucocorticoid hormone action at an autocrine level. The molecular basis for the putative human 11beta-HSD1 'knockout'--'cortisone reductase deficiency'--has recently been described, an observation that also answers a long standing conundrum relating to the set-point of 11beta-HSD1 activity. In each case, these clinical studies have been underpinned by studies in vitro and the manipulation of enzyme expression in vivo using recombinant mouse models.


Asunto(s)
11-beta-Hidroxiesteroide Deshidrogenasas/metabolismo , Comunicación Autocrina , Cortisona/metabolismo , Hidrocortisona/metabolismo , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/deficiencia , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/genética , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/metabolismo , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 2/metabolismo , Animales , Glaucoma/enzimología , Humanos , Hipertensión/enzimología , Resistencia a la Insulina , Ratones , Ratones Noqueados , Modelos Animales , Obesidad/enzimología , Osteoporosis/enzimología
16.
J Clin Endocrinol Metab ; 87(1): 57-62, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11788623

RESUMEN

Cushing's syndrome invariably presents with a classical phenotype comprising central adiposity, prominence of dorsal, supraclavicular and temporal fat pads, bruising, abdominal striae, proximal myopathy, and hypertension. We report the case of a 20-yr-old student with pituitary-dependent Cushing's syndrome who was spared this classical phenotype because of a defect in the peripheral conversion of cortisone to cortisol. She presented to her general practitioner with secondary amenorrhea. Clinical examination revealed normal fat distribution (body mass index, 20.9 kg/m(2)), absence of hirsutism, myopathy, or bruising; her blood pressure ranged from 115/70 to 122/82 mm Hg. She was investigated for biochemical hypercortisolemia because of a mildly elevated random circulating cortisol (serum cortisol, 661 nmol/liter). Cushing's syndrome was confirmed on the basis of repeatedly elevated urinary free cortisols (831-1049; reference range, <350 nmol/24 h), failure of low-dose dexamethasone suppression (611 nmol/liter) and loss of circadian cortisol secretion. Investigations suggested Cushing's disease; there was suppression after high-dose dexamethasone (<20 nmol/liter) and a 950% increase in ACTH after stimulation with CRH. Pituitary magnetic resonance imaging revealed a 3-mm adenoma within the pituitary gland. Urinary corticosteroid metabolites were analyzed by gas chromatography-mass spectrometry and demonstrated a decreased THF+allo-THF/THE ratio of 0.66 (mean +/- SE in Cushing's disease, 1.74 +/- 0.24) suggesting a defect in 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1), an enzyme that converts the inactive glucocorticoid cortisone to active cortisol. Transphenoidal microadenomectomy was performed, and histology confirmed the diagnosis of a corticotroph adenoma. Postoperatively, serum cortisol was undetectable and replacement therapy was commenced. Subsequent investigations revealed a significantly impaired ability to convert an oral dose of cortisone acetate (25 mg) to cortisol, reduced serum cortisol to cortisone ratios, and a reduced serum half-life for cortisol (57.3 min). These results provide strong evidence for a partial defect in 11beta-HSD1 activity and concomitant increase in cortisol clearance rate. We have described a case of Cushing's disease that failed to present with a classical phenotype, and we postulate that this is due to a partial defect of 11beta-HSD1 activity, the defect in cortisone to cortisol conversion increasing cortisol clearance and thus protecting the patient from the effects of cortisol excess. This observation may help to explain individual susceptibility to the adverse effects of glucocorticoids.


Asunto(s)
Síndrome de Cushing/genética , Hidroxiesteroide Deshidrogenasas/deficiencia , 11-beta-Hidroxiesteroide Deshidrogenasas , Adulto , Cortisona/sangre , Cortisona/metabolismo , Síndrome de Cushing/metabolismo , Síndrome de Cushing/patología , Femenino , Humanos , Hidrocortisona/sangre , Hidrocortisona/metabolismo , Fenotipo
17.
Clin Colorectal Cancer ; 9(3): 179-82, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20643624

RESUMEN

Angiolymphoid hyperplasia with eosinophilia (AHE) of the colon is a rare entity. Since 1997, to our knowledge only 2 similar cases have been documented in the literature. Here, we report a third case that presented as a transverse colonic mass mimicking cancer both clinically and radiologically. Microscopically classic morphologic criteria of this entity were observed, which consisted of both a vascular proliferation and an inflammatory component rich in eosinophils without any malignant features. Whether AHE is a reactive process or a neoplastic process (either a benign vascular neoplasm or a T-cell lymphoproliferative disorder) is still under debate. However, it is important to recognize this entity as a cause of colonic mass to avoid a misdiagnosis of malignancy.


Asunto(s)
Hiperplasia Angiolinfoide con Eosinofilia/patología , Enfermedades del Colon/patología , Neoplasias del Colon/patología , Adulto , Diagnóstico Diferencial , Femenino , Neoplasias de Cabeza y Cuello/complicaciones , Hemangioma/complicaciones , Humanos , Neoplasias Ováricas/complicaciones
18.
Transfusion ; 48(7): 1398-402, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18422842

RESUMEN

BACKGROUND: Chimerism is defined as the presence of two genetically distinct cell populations in an organism. Few cases of phenotypically normal dispermic chimeras have been reported and most showed abnormalities on blood typing. CASE REPORT: A 32-year-old man was diagnosed with acute myelomonocytic leukemia. He clearly typed as group A, D-. No abnormalities of sexual development were identified on multiple physical exams, previous exploratory surgery, or CT scans. Molecular HLA typing (sequence-specific primers) in preparation for stem cell transplant showed the patient to have three HLA-B* and three HLA-Cw* alleles. Initial serologic HLA typing reported two haplotypes, but on subsequent review reactions for a third HLA-B antigen that were initially deemed to be false-positive reactions were identified. Two of 10 microsatellite short tandem repeat (STR) loci also showed three distinct alleles in blood and buccal samples. In all studies the third allele was attributable to a dual paternal contribution. CONCLUSION: This case represents dispermic chimerism, with one maternal and two paternal haplotypes variably distributed throughout body tissues in a phenotypically normal man without abnormalities in blood typing. The presence of additional alleles that may have been undetected or dismissed by serologic typing should be carefully investigated and verified by molecular techniques. Molecular HLA typing may increase the accurate identification of phenotypically normal chimeras and aid in selecting proper donors for transplantation to reduce graft-versus-host disease and transplant rejection in these patients.


Asunto(s)
Quimerismo , Prueba de Histocompatibilidad/métodos , Trasplante de Células Madre , Adulto , Antígenos HLA-B/genética , Antígenos HLA-C/genética , Haplotipos/genética , Humanos , Leucemia Mielomonocítica Aguda/cirugía , Masculino , Repeticiones de Microsatélite/genética , Análisis de Secuencia de ADN
19.
Hum Pathol ; 39(12): 1784-91, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18701138

RESUMEN

Gastrointestinal stromal tumors, the most common mesenchymal tumors of the gastrointestinal tract, are characterized by strong expression of c-Kit protein. Recently, it has been shown that gastrointestinal stromal tumors may also contain alterations of genes involved in the regulation of cell cycle. In this study, we evaluate the prevalence and clinical significance of cyclin D1 and D3, Ki-67, p27, and retinoblastoma protein expression in a group of 50 human gastrointestinal stromal tumors selected from the files of the Moffitt Cancer Center. Tissue sections from each case were subjected to immunostaining using the avidin-biotin complex method. Cyclin D1 nuclear positivity was detected in 21 of 50 (42%) and cyclin D3 in 24 of 50 (48%) cases. p27 high immunoreactivity and negative or decreased retinoblastoma protein expression were identified in 33 of 50 (66%) gastrointestinal stromal tumors. In 19 of 50 (38%) tumors, Ki-67 had high labeling index. Direct correlation was observed between cyclin D3 and p27 expression (P < .0001), and between cyclin D1 and retinoblastoma protein (P = .03). Coexpression of cyclin D3 and p27 was demonstrated by immunofluorescence. The p27 protein expression inversely correlated with tumor size (P = .004), but was not correlated with tumor grade (P = .12). Ki-67 directly correlated with both tumor size (P = .03) and tumor grade (P = .008). We report a direct correlation between cyclin D3 and p27 expression in gastrointestinal stromal tumors. Additional alterations in cyclin D1, Ki-67, and retinoblastoma protein expression indicate a disregulated cell cycle in these tumors.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Núcleo Celular/metabolismo , Ciclinas/metabolismo , Tumores del Estroma Gastrointestinal/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Núcleo Celular/patología , Ciclina D3 , Inhibidor p27 de las Quinasas Dependientes de la Ciclina , Femenino , Tumores del Estroma Gastrointestinal/patología , Humanos , Técnicas para Inmunoenzimas , Antígeno Ki-67/metabolismo , Masculino , Persona de Mediana Edad , Proteína de Retinoblastoma/metabolismo
20.
Am J Dermatopathol ; 29(5): 467-9, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17890916

RESUMEN

Hemophagocytic syndrome includes fever, hepatosplenomegaly, cytopenias, coagulopathy, and abnormal liver function tests, with some patients developing lymphadenopathy and cutaneous eruptions. Herein we report two cases of dermal perivascular hemophagocytosis identified in skin biopsies of two patients with no additional symptoms attributable to hemophagocytic syndrome. Biopsies showed capillary ectasia with dermal perivascular infiltrates. The overlying epidermis and adjacent subcutaneous fat was unremarkable. The infiltrate consisted of perivascular neutrophils and benign histiocytes with predominately phagocytized erythrocytes and occasional engulfed karyorrhectic debris. Perivascular nuclear dust (leukocytoclasia) and extravasated erythrocytes were present, but other factors typically found in leukocytoclastic vasculitis were absent, namely fibrin deposition and endothelial hypertrophy and/or necrosis. This appears to be hemophagocytosis, possibly associated with late lesions of leukocytoclastic vasculitis. Both hemophagocytosis and leukocytoclastic vasculitis are associated with activated immunity with increased cytokines and/or immune complexes. It is important to consider this uncommon finding in the evaluation of indeterminate cutaneous eruptions.


Asunto(s)
Exantema/diagnóstico , Linfohistiocitosis Hemofagocítica/diagnóstico , Biopsia , Capilares/patología , Dilatación Patológica/patología , Exantema/etiología , Humanos , Linfohistiocitosis Hemofagocítica/complicaciones , Masculino , Persona de Mediana Edad , Piel/irrigación sanguínea , Piel/patología , Vasculitis Leucocitoclástica Cutánea/patología
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