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1.
J Genet Couns ; 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39189540

RESUMEN

The goal of this study was to assess the feasibility of using exome (ES) and genome sequencing (GS) in guiding preconception genetic screening (PCGS) for couples who are planning to conceive by creating a workflow for identifying risk alleles for autosomal recessive (AR) and X-linked (XL) disorders without the constraints of a predetermined, targeted gene panel. There were several limitations and challenges related to reporting and the technical aspects of ES and GS, which are listed in the discussion. We selected 150 couples from a cohort of families (trios) enrolled in a research protocol where the goal was to define the genetic etiology of disease in an affected child. Pre-existing, de-identified parental sequencing data were analyzed to define variants that would place the couple at risk of having a child affected by an AR or XL disorder. We identified 17 families who would be selected for counseling about risk alleles. We noted that only 3 of these at-risk couples would be identified if we limited ourselves to the current ACMG-recommended expanded carrier screening gene panel. ES and GS successfully identified couples who are at risk of having a child with a rare AR or XL disorder that would have been missed by the current recommended guidelines. Current limitations of this approach include ethical concerns, difficulties in reporting results including variant calling due to the rare nature of some of the variants, determining which disorders to report, as well as technical difficulties in detecting certain variants such as repeat expansions.

2.
Ann Oncol ; 27(6): 1100-1106, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26912560

RESUMEN

BACKGROUND: Information on the impact of other cancers (OCs) in long-term survivors (LTSs) of chronic lymphocytic leukemia (CLL) is limited. PATIENTS AND METHODS: Patients with CLL who survived >10 years were defined as LTSs of CLL. We calculated standardized incidence ratios (SIRs) to compare the incidence of OC in LTS of CLL versus the general population. A multivariable model was used to identify independent predictors of OC. Overall survival was analyzed as a function of the presence of OC. RESULTS: Among 797 LTSs of CLL, the cumulative frequency of OC was 36%, similar between 570 patients (72%) who required treatment for CLL (TRT) and 227 (28%) who remained untreated (UT). The most common OC in both groups was non-melanoma skin cancer, followed by prostate cancer, breast cancer, melanoma, lung cancer, and leukemia in TRT patients, and by prostate cancer, breast cancer, melanoma, lung cancer, and gastrointestinal tumors in the UT group. The SIR for all OC was 1.2 (P = 0.034). It was higher in males (SIR 1.31; P = 0.013) and patients <60 years (SIR 1.27; P = 0.027). A higher SIR was shown for secondary leukemia, melanoma, and head-and-neck cancers, whereas a lower SIR was found for gastrointestinal and bladder cancers. Independent predictors of OC development were advanced age, male gender, and lower platelets. The survival of patients with OC was 16.2 months and that of patients without OC 22.9 years. CONCLUSIONS: LTSs of CLL have an increased incidence of OC compared with the general population. CLL therapy is not a risk factor for OC in LTSs of CLL. The presence of an OC in these patients may be associated with shorter survival.


Asunto(s)
Supervivientes de Cáncer , Leucemia Linfocítica Crónica de Células B/epidemiología , Neoplasias Primarias Secundarias/epidemiología , Pronóstico , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/patología , Femenino , Neoplasias Gastrointestinales/tratamiento farmacológico , Neoplasias Gastrointestinales/epidemiología , Neoplasias Gastrointestinales/patología , Humanos , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Leucemia Linfocítica Crónica de Células B/patología , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/epidemiología , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Neoplasias Primarias Secundarias/tratamiento farmacológico , Neoplasias Primarias Secundarias/patología , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/epidemiología , Neoplasias de la Próstata/patología , Factores de Riesgo , Programa de VERF
3.
Am J Transplant ; 16(3): 1021-30, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26523372

RESUMEN

Clinical hepatocyte transplantation is hampered by low engraftment rates and gradual loss of function resulting in incomplete correction of the underlying disease. Preconditioning with partial hepatectomy improves engraftment in animal studies. Our aim was to study safety and efficacy of partial hepatectomy preconditioning in clinical hepatocyte transplantation. Two patients with Crigler-Najjar syndrome type I underwent liver resection followed by hepatocyte transplantation. A transient increase of hepatocyte growth factor was seen, suggesting that this procedure provides a regenerative stimulus. Serum bilirubin was decreased by 50%, and presence of bilirubin glucuronides in bile confirmed graft function in both cases; however, graft function was lost due to discontinuation of immunosuppressive therapy in one patient. In the other patient, serum bilirubin gradually increased to pretransplant concentrations after ≈600 days. In both cases, loss of graft function was temporally associated with emergence of human leukocyte antigen donor-specific antibodies (DSAs). In conclusion, partial hepatectomy in combination with hepatocyte transplantation was safe and induced a robust release of hepatocyte growth factor, but its efficacy on hepatocyte engraftment needs to be evaluated with additional studies. To our knowledge, this study provides the first description of de novo DSAs after hepatocyte transplantation associated with graft loss.


Asunto(s)
Formación de Anticuerpos/inmunología , Síndrome de Crigler-Najjar/inmunología , Rechazo de Injerto/etiología , Antígenos HLA/inmunología , Hepatectomía/efectos adversos , Hepatocitos/trasplante , Trasplante de Hígado/efectos adversos , Donantes de Tejidos , Adolescente , Adulto , Niño , Síndrome de Crigler-Najjar/cirugía , Femenino , Humanos , Lactante , Masculino , Complicaciones Posoperatorias , Pronóstico
5.
Parasitol Res ; 114(3): 1217-20, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25563618

RESUMEN

Third-stage larvae of the anisakid nematode Contracaecum osculatum were recovered from livers of Atlantic cod (Gadus morhua) caught in the Baltic Sea (June 2014) and used for experimental infection of two pigs (one male and one female). Each pig received 215 larvae by oral infection (feeding with minced cod liver containing live nematode larvae). Pigs were euthanized after 5 days, necropsied, and subjected to parasitological investigation. A total of 12 larvae were found penetrating the mucosa of the ventricle (7 in the female pig and 5 in the male pig) eliciting a granulomatous reaction at the penetration site. Four non-attached larvae were found in the female pig stomach and one in the male pig. Petechial bleeding was observed at several locations in the ventricular mucosa where larvae were located. Histological examination of the stomach mucosa revealed a massive cellular infiltration (giant cells, lymphocytes, macrophages, granulocytes, and fibroblast like cells) around the penetrating larva. Mononuclear and polymorphonuclear cells containing eosinophilic granulae were particularly prominent in the granulomas. Reactions correspond to reactions in pigs following experimental infection with the human pathogenic anisakid larvae Anisakis sp. and Pseudoterranova sp. which suggests that C. osculatum might have a zoonotic potential as well.


Asunto(s)
Ascaridoidea , Gadus morhua , Mucosa Gástrica/parasitología , Granuloma/veterinaria , Gastropatías/veterinaria , Enfermedades de los Porcinos/parasitología , Animales , Femenino , Mucosa Gástrica/patología , Granuloma/parasitología , Granuloma/patología , Humanos , Larva/fisiología , Masculino , Infecciones por Nematodos/parasitología , Infecciones por Nematodos/patología , Gastropatías/parasitología , Gastropatías/patología , Porcinos , Enfermedades de los Porcinos/patología
6.
Mol Phylogenet Evol ; 78: 36-42, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24814356

RESUMEN

The Ciliophora is one of the most studied protist lineages because of its important ecological role in the microbial loop. While there is an abundance of molecular data for many ciliate groups, it is commonly limited to the 18S ribosomal RNA locus. There is a paucity of data when it comes to availability of protein-coding genes especially for taxa that do not belong to the class Oligohymenophorea. To address this gap, we have sequenced EST libraries for 11 ciliate species. A supermatrix was constructed for phylogenomic analysis based on 158 genes and 42,158 characters and included 16 ciliates, four dinoflagellates and nine apicomplexans. This is the first multigene-based analysis focusing on the phylum Ciliophora. Our analyses reveal two robust superclades within the Intramacronucleata; one composed of the classes Spirotrichea, Armophorea and Litostomatea (SAL) and another with Colpodea and Oligohymenophorea. Furthermore, we provide corroborative evidence for removing the ambiguous taxon Protocruzia from the class Spirotrichea and placing it as incertae sedis in the phylum Ciliophora.


Asunto(s)
Cilióforos/clasificación , Filogenia , Cilióforos/genética , Genómica , ARN Ribosómico 18S/genética
7.
J Intern Med ; 272(3): 201-23, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22789058

RESUMEN

Inherited metabolic diseases of the liver are characterized by deficiency of a hepatic enzyme or protein often resulting in life-threatening disease. The remaining liver function is usually normal. For most patients, treatment consists of supportive therapy, and the only curative option is liver transplantation. Hepatocyte transplantation is a promising therapy for patients with inherited metabolic liver diseases, which offers a less invasive and fully reversible approach. Procedure-related complications are rare. Here, we review the experience of hepatocyte transplantation for metabolic liver diseases and discuss the major obstacles that need to be overcome to establish hepatocyte transplantation as a reliable treatment option in the clinic.


Asunto(s)
Trasplante de Células/métodos , Hepatocitos/citología , Hepatopatías/terapia , Errores Innatos del Metabolismo/terapia , Inmunidad Adaptativa , Animales , Técnicas de Cultivo de Célula , Senescencia Celular , Criopreservación , Humanos , Inmunidad Innata , Terapia de Inmunosupresión , Donantes de Tejidos , Acondicionamiento Pretrasplante
8.
Leukemia ; 25(9): 1459-66, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21617698

RESUMEN

Monoclonal B-cell lymphocytosis (MBL) is a hematologic condition wherein small B-cell clones can be detected in the blood of asymptomatic individuals. Most MBL have an immunophenotype similar to chronic lymphocytic leukemia (CLL), and 'CLL-like' MBL is a precursor to CLL. We used flow cytometry to identify MBL from unaffected members of CLL kindreds. We identified 101 MBL cases from 622 study subjects; of these, 82 individuals with MBL were further characterized. In all, 91 unique MBL clones were detected: 73 CLL-like MBL (CD5(+)CD20(dim)sIg(dim)), 11 atypical MBL (CD5(+)CD20(+)sIg(+)) and 7 CD5(neg) MBL (CD5(neg)CD20(+)sIg(neg)). Extended immunophenotypic characterization of these MBL subtypes was performed, and significant differences in cell surface expression of CD23, CD49d, CD79b and FMC-7 were observed among the groups. Markers of risk in CLL such as CD38, ZAP70 and CD49d were infrequently expressed in CLL-like MBL, but were expressed in the majority of atypical MBL. Interphase cytogenetics was performed in 35 MBL cases, and del 13q14 was most common (22/30 CLL-like MBL cases). Gene expression analysis using oligonucleotide arrays was performed on seven CLL-like MBL, and showed activation of B-cell receptor associated pathways. Our findings underscore the diversity of MBL subtypes and further clarify the relationship between MBL and other lymphoproliferative disorders.


Asunto(s)
Linfocitos B/patología , Biomarcadores de Tumor/genética , Perfilación de la Expresión Génica , Leucemia Linfocítica Crónica de Células B/genética , Leucemia Linfocítica Crónica de Células B/inmunología , Linfocitosis/patología , Biomarcadores de Tumor/metabolismo , Citometría de Flujo , Humanos , Inmunofenotipificación , Hibridación Fluorescente in Situ , Leucemia Linfocítica Crónica de Células B/terapia , Análisis de Secuencia por Matrices de Oligonucleótidos , Pronóstico , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
9.
Int J Androl ; 34(4 Pt 2): e59-67, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21128977

RESUMEN

Androgen levels during critical periods of testicular development may be involved in the aetiology of testicular germ cell tumours (TGCT). We evaluated the roles of adolescent and early adult life correlates of androgen exposure and TGCT in a hospital-based case-control study. TGCT cases (n=187) and controls (n=148), matched on age, race and state of residence, participated in the study. Unconditional logistic regression was used to estimate associations between TGCT and male pattern baldness, severe acne, markers of puberty onset and body size. Cases were significantly less likely to report hair loss than controls [odds ratio (OR): 0.6; 95% confidence interval (CI): 0.4, 1.0]. Amount of hair loss, increasing age at onset and increasing rate of loss were all inversely associated with TGCT (rate of hair loss: p-trend=0.03; age at onset: p-trend=0.03; amount of hair loss: p-trend=0.01). History of severe acne was inversely associated with TGCT (OR: 0.5; 95% CI: 0.3, 0.9) and height was positively associated with TGCT (p-trend=0.02). Increased endogenous androgen levels during puberty and early adulthood may be associated with a decreased risk of TGCT. Additional studies of endogenous hormone levels during puberty and early adult life are warranted, especially studies evaluating the role of androgen synthesis, metabolism and uptake.


Asunto(s)
Acné Vulgar/epidemiología , Alopecia/epidemiología , Neoplasias de Células Germinales y Embrionarias/epidemiología , Neoplasias Testiculares/epidemiología , Adolescente , Adulto , Edad de Inicio , Andrógenos/sangre , Estudios de Casos y Controles , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Testículo/embriología , Testículo/patología
10.
Ann Oncol ; 21(10): 2107-2111, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20348145

RESUMEN

BACKGROUND: We sought to investigate the characteristics and survival rate of patients with gastrointestinal stromal tumor (GIST) associated with other primary malignancies. PATIENTS AND METHODS: A total of 783 patients with GIST were identified from 1995 to 2007. Additional primaries included tumors not considered metastasis, invasion, or recurrence of GIST, nor non-melanoma skin cancer. Data on gender, age at diagnosis, follow-up time after diagnosis, and death were collected. RESULTS: Of the 783 patients with GIST, 153(20%) were identified with at least one additional primary. Patients with additional primaries were more often men (M : F 1.5 versus 1.3) and older (66 versus 53 years). More patients had another cancer diagnosed before (134) than after (52) GIST. Primaries observed before GIST were cancers of the prostate (25), breast (12), esophagus (9), and kidney (7) and melanoma (6). Lung (5) and kidney (5) primaries were the most frequent after GIST. The 5-year survival was 68% for patients with primaries before GIST, 61% for patients with primaries after GIST, 58% for patients with GIST only, and 49% for patients with two or more primaries in addition to GIST (P = 0.002). CONCLUSIONS: Approximately 20% of patients with GIST develop other cancers. Inferior median 5-year survival was observed in patients with GIST with two or more other cancers. The etiology and clinical implications of other malignancies in patients with GIST should be investigated.


Asunto(s)
Tumores del Estroma Gastrointestinal/mortalidad , Neoplasias Primarias Múltiples/mortalidad , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Terapia Combinada , Femenino , Estudios de Seguimiento , Tumores del Estroma Gastrointestinal/patología , Tumores del Estroma Gastrointestinal/terapia , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasias Primarias Múltiples/patología , Neoplasias Primarias Múltiples/terapia , Pronóstico , Tasa de Supervivencia , Adulto Joven
11.
Mol Psychiatry ; 15(10): 996-1005, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19455149

RESUMEN

Chromosome 17q11-q21 is a region of the genome likely to harbor susceptibility to autism (MIM(209850)) based on earlier evidence of linkage to the disorder. This linkage is specific to multiplex pedigrees containing only male probands (MO) within the Autism Genetic Resource Exchange (AGRE). Earlier, Stone et al.(1) completed a high-density single nucleotide polymorphism association study of 13.7 Mb within this interval, but common variant association was not sufficient to account for the linkage signal. Here, we extend this single nucleotide polymorphism-based association study to complete the coverage of the two-LOD support interval around the chromosome 17q linkage peak by testing the majority of common alleles in 284 MO trios. Markers within an interval containing the gene, CACNA1G, were found to be associated with Autism Spectrum Disorder at a locally significant level (P=1.9 × 10(-5)). While establishing CACNA1G as a novel candidate gene for autism, these alleles do not contribute a sufficient genetic effect to explain the observed linkage, indicating that there is substantial genetic heterogeneity despite the clear linkage signal. The region thus likely harbors a combination of multiple common and rare alleles contributing to the genetic risk. These data, along with earlier studies of chromosomes 5 and 7q3, suggest few if any major common risk alleles account for Autism Spectrum Disorder risk under major linkage peaks in the AGRE sample. This provides important evidence for strategies to identify Autism Spectrum Disorder genes, suggesting that they should focus on identifying rare variants and common variants of small effect.


Asunto(s)
Trastorno Autístico/genética , Canales de Calcio Tipo T/genética , Cromosomas Humanos Par 17 , Polimorfismo de Nucleótido Simple , Trastorno Autístico/epidemiología , Niño , Femenino , Estudios de Seguimiento , Dosificación de Gen , Marcadores Genéticos , Predisposición Genética a la Enfermedad/epidemiología , Haplotipos , Humanos , Desequilibrio de Ligamiento , Escala de Lod , Masculino , Factores de Riesgo
12.
J Health Econ ; 28(3): 748-57, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19272663

RESUMEN

When entering the job market, nurses choose among different kind of jobs. Each of these jobs is characterized by wage, sector (primary care or hospital) and shift (daytime work or shift). This paper estimates a multi-sector-job-type random utility model of labor supply on data for Norwegian registered nurses (RNs) in 2000. The empirical model implies that labor supply is rather inelastic; 10% increase in the wage rates for all nurses is estimated to yield 3.3% increase in overall labor supply. This modest response shadows for much stronger inter-job-type responses. Our approach differs from previous studies in two ways: First, to our knowledge, it is the first time that a model of labor supply for nurses is estimated taking explicitly into account the choices that RN's have regarding work place and type of job. Second, it differs from previous studies with respect to the measurement of the compensations for different types of work. So far, it has been focused on wage differentials. But there are more attributes of a job than the wage. Based on the estimated random utility model we therefore calculate the expected value of compensation that makes a utility maximizing agent indifferent between types of jobs, here between shift work and daytime work. It turns out that Norwegian nurses working shifts may be willing to work shift relative to daytime work for a lower wage than the current one.


Asunto(s)
Enfermeras y Enfermeros/economía , Salarios y Beneficios , Tolerancia al Trabajo Programado , Femenino , Humanos , Modelos Econométricos , Noruega , Enfermeras y Enfermeros/provisión & distribución
13.
Xenobiotica ; 36(10-11): 989-1012, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17118917

RESUMEN

Previous studies have found that, compared with Whites, Hispanic donor livers had elevated expression of CYP2 enzymes, gene products regulated by the constitutive androstane receptor (CAR). The objectives of the current study were to determine (1) the CAR activation signature in human liver (2) whether other drug detoxification (absorption, distribution, metabolism and excretion (ADME)) genes were differentially expressed in Hispanic versus White livers, and (3) the extent of overlap in the CAR and Hispanic liver transcriptomes. The CAR transcriptome (ADME genes differentially expressed following phenobarbital versus vehicle treatment of human hepatocytes) and the Hispanic liver transcriptome (ADME genes differentially expressed in Hispanic versus White livers) were identified using Affymetrix oligonucleotide arrays. Quantitative real-time polymerase chain reaction (PCR) was used to verify candidate genes in a larger sample size. Comparison of the CAR and Hispanic liver ADME transcriptomes revealed a significant association between the gene changes. Sixty-four per cent of the ADME genes induced more than twofold by phenobarbital were also induced in Hispanics, and 14% of the ADME genes repressed more than twofold by phenobarbital were repressed in Hispanics. In conclusion, compared with Whites, Hispanic donor livers have increased expression of many genes that are transcriptionally regulated by CAR. This result has practical implications to the drug treatment of Hispanic patients.


Asunto(s)
Hispánicos o Latinos/genética , Hígado/metabolismo , Receptores Citoplasmáticos y Nucleares/genética , Factores de Transcripción/genética , Transcripción Genética , Población Blanca/genética , Xenobióticos/metabolismo , Adolescente , Adulto , Anciano , Animales , Hidrocarburo de Aril Hidroxilasas/genética , Receptor de Androstano Constitutivo , Femenino , Perfilación de la Expresión Génica , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Hígado/citología , Masculino , Ratones , Ratones Endogámicos C57BL , Persona de Mediana Edad , Fenobarbital/farmacología , Receptor X de Pregnano , ARN Mensajero/genética , ARN Mensajero/metabolismo , Receptores Citoplasmáticos y Nucleares/deficiencia , Receptores de Esteroides/genética , Reproducibilidad de los Resultados , Donantes de Tejidos , Factores de Transcripción/deficiencia
14.
Transplant Proc ; 38(4): 1179-80, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16757299

RESUMEN

Hepatocyte transplantation has been used for temporary metabolic support of patients in end-stage liver failure awaiting whole organ transplantation as a method to support liver function and facilitate regeneration of the native liver in cases of fulminant hepatic failure and as a "cellular therapy" for patients with genetic defects in vital liver functions. The aim of this paper was to discuss the basic research that led to clinical hepatocyte transplantation, the published clinical experience with this experimental technique, and some possible future uses of hepatocyte transplantation.


Asunto(s)
Hepatocitos/trasplante , Hepatopatías/cirugía , Animales , Humanos , Modelos Animales
15.
Toxicol In Vitro ; 20(2): 135-53, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16359840

RESUMEN

Anticancer drugs have a complex pharmacological and toxicological profile with a narrow therapeutic index. It is therefore critical to understand the factors that contribute to the marked intersubject variability in the pharmacokinetics and pharmacodynamics often observed with anticancer compounds. Since hepatic and extra-hepatic drug metabolism represents a major drug disposition pathway, extensive efforts are made to thoroughly investigate metabolism of anticancer compounds during the pre-clinical and clinical development phases as well as to address issues encountered during the clinical use of an approved drug. In recent years there has been a significant paradigm shift in pre-clinical/non-clinical drug metabolism studies. Most importantly, this has included a reduced reliance on animal models and increased use of human tissues (i.e. human liver microsomes and other cellular fractions, primary culture of human hepatocytes, cDNA expressed human-specific enzymes and cell-based reporter assays). Typically, experiments are performed using these tools to identify the phase I and/or phase II enzymes involved in metabolism of the drug/investigational agent and for metabolic fingerprinting. Additionally, issues pertaining to the rate, extent and mechanism(s) of the inhibition or induction of the metabolic pathways are also investigated. These studies provide important clues about various aspects of the disposition of a therapeutic agent including first-pass metabolism, elimination half-life, overall bioavailability and the potential for drug-drug interactions. The methodologies used for in vitro assessment of drug metabolism and their applications to drug development and clinical therapeutics with special emphasis on anticancer drugs are reviewed in this manuscript.


Asunto(s)
Antineoplásicos/metabolismo , Hígado/metabolismo , Biotransformación , Células Cultivadas , Evaluación Preclínica de Medicamentos , Interacciones Farmacológicas , Hepatocitos/metabolismo , Humanos , Técnicas In Vitro , Hígado/enzimología , Microsomas Hepáticos/metabolismo , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo
16.
Arch Environ Contam Toxicol ; 49(3): 396-402, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16132412

RESUMEN

An initial survey of lead levels in American woodcock (Scolopax minor) from Wisconsin was conducted in 1998 using wing bones from hunter-donated woodcock. The results of this initial survey indicated that young-of-year woodcock were accumulating extremely high levels of lead in their bones. Similar collections were made (using steel shot) between 1999 and 2001. The combined results of this collection indicated that 43.4% of young-of-year woodcock (range 1.5-220.0 microg/g dry wt) and 70% of woodcock chicks (range 9.6-93.0 microg/g dry wt) had bone lead levels in the elevated range (>20 microg/g dry wt). Blood samples were collected from chicks at a site considered elevated based on bone lead results (Mead Wildlife Area) and a site considered background (Navarino Wildlife Area). These samples were analyzed for lead concentration and aminolevulinic acid dehydratase activity. The mean blood lead concentrations of woodcock chicks from both sites did not reach levels that are considered elevated in waterfowl (>0.200 microg/ml). However, blood lead concentrations of chicks from the Mead Wildlife Area were significantly higher than lead levels in chicks from Navarino Wildlife Area (p = 0.002). Although the ultimate sources of lead exposure for Wisconsin woodcock currently remain unidentified, anthropogenic sources cannot be ruled out. Our results indicate that elevated lead exposure in Wisconsin woodcock is common and begins shortly after hatch.


Asunto(s)
Charadriiformes/metabolismo , Contaminantes Ambientales/metabolismo , Plomo/metabolismo , Animales , Huesos/química , Monitoreo del Ambiente , Contaminantes Ambientales/análisis , Contaminantes Ambientales/sangre , Plomo/análisis , Plomo/sangre , Hígado/química , Porfobilinógeno Sintasa/metabolismo , Wisconsin
17.
Leukemia ; 19(11): 1912-8, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16167059

RESUMEN

Little is known about the etiology of myelodysplastic syndromes (MDS). A hospital-based case-control study of 354 adult de novo MDS cases and 452 controls was conducted to investigate associations between lifestyle characteristics and MDS risk. The distribution by French-American-British (FAB) type was 67 (19%) refractory anemia (RA), 38 (11%) refractory anemia with ringed sideroblasts (RARS), 43 (12%) chronic myelomonocytic leukemia (CMML), 136 (38%) RA with excess blasts (RAEB), and 70 (20%) RAEB in transformation (RAEBT). Multivariate logistic regression analyses were performed among all MDS cases and among each FAB type and gender. For all MDS combined, family history of hematopoietic cancer (odds ratio (OR) = 1.92), smoking (OR = 1.65), and exposure to agricultural chemicals (OR = 4.55) or solvents (OR = 2.05) were associated with MDS risk. Among RA/RARS cases, smoking (OR = 2.23) and agricultural chemical exposure (OR = 5.68) were the only risk factors identified. For RAEB/RAEBT cases, family history of hematopoietic cancer (OR = 2.10), smoking (OR = 1.52), and exposure to agricultural chemicals (OR = 3.79) or solvents (OR = 2.71) were independent risk factors. Drinking wine reduced risk for all FAB types by almost 50% (OR = 0.54). We found a joint effect between smoking and chemical exposure with the highest risk among smokers exposed to solvents/agricultural chemicals (OR = 3.22). Results from this large study suggest that several factors play a role in MDS predisposition with possible joint effects. Risk profiles seem to differ by FAB type and gender.


Asunto(s)
Exposición a Riesgos Ambientales , Predisposición Genética a la Enfermedad , Síndromes Mielodisplásicos/etiología , Fumar/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Femenino , Humanos , Estilo de Vida , Masculino , Persona de Mediana Edad , Síndromes Mielodisplásicos/genética , Oportunidad Relativa , Plaguicidas/envenenamiento , Factores de Riesgo , Factores Sexuales , Solventes/envenenamiento
18.
Xenobiotica ; 35(5): 419-38, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-16012075

RESUMEN

1. Previous studies reported that rat hepatocytes overlaid with extracellular matrix components (Matrigel) maintain the expression and responsiveness of drug-metabolizing enzymes. However, whether Matrigel provides similar advantages in human hepatocytes remains largely uncertain.2. The influence of Matrigel-overlay on the constitutive and phenobarbital- and oltipraz-inducible expression of nine biotransformation enzymes, cytochrome P450s 1A1, 1A2, 2B6, 3A4, and glutathione S-transferases A1, A2, M1, T1, P1, in primary human hepatocytes was evaluated.3. Hepatocytes from five livers were maintained on a rigid collagen substratum with or without Matrigel overlay and treated for 48?h with two doses of each inducer. Quantitative RT-PCR, and for selected genes, immunoblot and enzyme activity analyses, demonstrated that human hepatocytes overlaid with Matrigel showed consistently higher constitutive and inducible expression of biotransformation genes. 4. Phenobarbital-mediated responsiveness of cytochrome P450 2B6, a potential indicator of hepatocyte differentiation status, was markedly higher in overlaid relative to non-overlaid hepatocytes. 5. It is concluded that an Matrigel overlay facilitates the maintenance and induction of xenobiotic metabolizing enzymes in primary cultures of human hepatocytes.


Asunto(s)
Sistema Enzimático del Citocromo P-450/genética , Regulación Enzimológica de la Expresión Génica , Hepatocitos/enzimología , Preparaciones Farmacéuticas/metabolismo , Adulto , Animales , Biotransformación , Colágeno , Citocromo P-450 CYP1A1/metabolismo , Sistema Enzimático del Citocromo P-450/biosíntesis , Sistema Enzimático del Citocromo P-450/metabolismo , Combinación de Medicamentos , Inducción Enzimática , Glutatión Transferasa/genética , Glutatión Transferasa/metabolismo , Humanos , Laminina , Persona de Mediana Edad , Proteoglicanos , Roedores
20.
Scand J Gastroenterol ; 39(6): 584-93, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15223685

RESUMEN

BACKGROUND: For hepatocyte transplantation as well as experimental purposes, it would be advantageous to be able to expand human hepatocytes in vitro. However, under serum-free conditions, even with supplements of HGF (hepatic growth factor) and EGF (epidermal growth factor), proliferation of human hepatocytes is hampered. The aim of this study was to identify differences in the proliferative capacity of cultured primary human hepatocytes related to the age of the liver donors. METHODS: Proliferation was determined by BrdU-uptake, ploidy was measured using propidium iodide staining and flow cytometry, and the expression of cell cycle related proteins was determined by Western blotting. RESULTS: During the initial culture, juvenile hepatocytes proliferated better than adult hepatocytes. The proliferation rate declined to barely detectable levels after 8 days in culture in both juvenile and adult hepatocytes. The higher proliferative capacity of juvenile hepatocytes was associated with a larger fraction of diploid cells and a higher viability. The expression of regulatory cell cycle related proteins was higher in juvenile than in adult hepatocytes. CONCLUSIONS: The proliferation of human hepatocytes in vitro is critically related to a large fraction of diploid hepatocytes. The expression of regulatory cell cycle proteins reflects the proliferative capacity of cultured human hepatocytes. Juvenile as compared to adult human hepatocytes may be better suited for expansion in culture and could have a stronger repopulation capacity in vivo.


Asunto(s)
División Celular/fisiología , Hepatocitos/fisiología , Factores de Edad , Anciano , Técnicas de Cultivo de Célula , Niño , Preescolar , Quinasas Ciclina-Dependientes/metabolismo , Ciclinas/metabolismo , Diploidia , Femenino , Hepatocitos/trasplante , Humanos , Masculino , Persona de Mediana Edad , Poliploidía , Antígeno Nuclear de Célula en Proliferación/metabolismo
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