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1.
Environ Monit Assess ; 191(Suppl 1): 329, 2019 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-31222449

RESUMEN

The National Wetland Condition Assessment (NWCA) is one of a series of probability-based National Aquatic Resource Surveys (NARS) conducted by the U.S. Environmental Protection Agency (USEPA) to provide a comprehensive assessment of the condition of the Nation's waters. Randomized design and standardized training and protocols allow USEPA to analyze data that are nationally consistent and regionally relevant. Each NARS assessment was preceded by careful consideration of key logistical elements that included pre-survey planning, training, sampling logistics, and laboratory analysis. Numerous state, tribal, and contractor crews were supported across the country for each assessment; sampling and sample analyses were tracked from initiation; laboratory analyses were completed at USEPA, state, regional, and contract laboratories; and the data analyses and reporting were completed by USEPA-led workgroups, states, and contractors. The complexity and difficulty of each step offered unique challenges and provided lessons learned for each of the NARS assessments. Major logistical elements for implementing large scale assessments that are constrained by sampling period and number and duration of visits are covered in this paper. These elements include sample transport, equipment and supplies, sampling and sample tracking, information management regional technical expertise, and a sound field training program. This paper describes how lessons from previous assessments were applied to the NWCA and how new challenges faced in the NWCA were addressed and carried forward into future surveys.


Asunto(s)
Conservación de los Recursos Hídricos/métodos , Monitoreo del Ambiente/estadística & datos numéricos , Humedales , Conservación de los Recursos Hídricos/tendencias , Ecología , Monitoreo del Ambiente/normas , Humanos , Laboratorios/normas , Estados Unidos , United States Environmental Protection Agency/organización & administración , United States Environmental Protection Agency/normas , United States Environmental Protection Agency/estadística & datos numéricos
2.
JAAPA ; 32(2): 12-16, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30640178

RESUMEN

Up to 4% of adults with blunt trauma suffer cervical spine injury. Clinicians who evaluate trauma patients can use validated clinical decision tools to assess whether patients are at risk for these injuries. Beyond these tools, imaging (most often CT) remains the mainstay of evaluation. Further challenges exist when patients have persistent pain or cannot be evaluated clinically. This article reviews the evidence available to assist clinicians in evaluating adults for significant cervical spine injury after blunt trauma.


Asunto(s)
Vértebras Cervicales/lesiones , Sistemas de Apoyo a Decisiones Clínicas , Traumatismos Vertebrales/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Heridas no Penetrantes/complicaciones , Humanos , Traumatismos Vertebrales/etiología
4.
Heredity (Edinb) ; 112(2): 99-104, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24002238

RESUMEN

Non-random association of alleles in the nucleus and cytoplasmic organelles, or cyto-nuclear linkage disequilibrium (LD), is both an important component of a number of evolutionary processes and a statistical indicator of others. The evolutionary significance of cyto-nuclear LD will depend on both its magnitude and how stable those associations are through time. Here, we use a longitudinal population genetic data set to explore the magnitude and temporal dynamics of cyto-nuclear disequilibria through time. We genotyped 135 and 170 individuals from 16 and 17 patches of the plant species Silene latifolia in Southwestern VA, sampled in 1993 and 2008, respectively. Individuals were genotyped at 14 highly polymorphic microsatellite markers and a single-nucleotide polymorphism (SNP) in the mitochondrial gene, atp1. Normalized LD (D') between nuclear and cytoplasmic loci varied considerably depending on which nuclear locus was considered (ranging from 0.005-0.632). Four of the 14 cyto-nuclear associations showed a statistically significant shift over approximately seven generations. However, the overall magnitude of this disequilibrium was largely stable over time. The observed origin and stability of cyto-nuclear LD is most likely caused by the slow admixture between anciently diverged lineages within the species' newly invaded range, and the local spatial structure and metapopulation dynamics that are known to structure genetic variation in this system.


Asunto(s)
Núcleo Celular/genética , Citoplasma/genética , Genoma de Planta , Desequilibrio de Ligamiento , Silene/genética , Genes Mitocondriales , Heterogeneidad Genética , Genética de Población , Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo
5.
Child Care Health Dev ; 40(1): 42-9, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22928492

RESUMEN

BACKGROUND: The Developmental Coordination Disorder Questionnaire (DCDQ'07) discriminates children with Developmental Coordination Disorder (DCD) from their peers. Studies employing the DCDQ have typically used clinical samples. To further validate the DCDQ'07, this study: (1) described its distributions in a population-based sample, and a sample of children with DCD; (2) explored sex and age differences at important cut-points; and (3) examined its factor structure. METHODS: This secondary analysis of data collected from 23 schools (n = 3151) included a sample of 3070 children (1526 boys, 1544 girls) and a sample of 122 children (73 boys, 49 girls) who met DCD diagnostic criteria. DCDQ'07 distributions were described by age and sex. Chi-square analyses were conducted using three clinically important percentile ranges; a factor analysis explored the construct validity of DCDQ scores. RESULTS: Parents of 3070 children (97.4%) completed the questionnaire independently. Significant sex differences were noted in both samples. Significant differences in proportions by sex, and DCDQ means by age were found in the population sample. A three-factor solution was found, accounting for 70.3% of the variance. CONCLUSIONS: This is one of the largest studies using the DCDQ'07 with a non-clinical sample. The three-factor solution, including item loading, was consistent with previous research. When using DCDQ cut-offs it is important to consider sex and age.


Asunto(s)
Discapacidades del Desarrollo/diagnóstico , Trastornos de la Destreza Motora/diagnóstico , Padres , Instituciones Académicas , Encuestas y Cuestionarios/normas , Distribución por Edad , Canadá/epidemiología , Niño , Análisis Factorial , Femenino , Humanos , Masculino , Prevalencia , Psicometría , Distribución por Sexo
6.
Leukemia ; 27(12): 2357-65, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23752175

RESUMEN

RNA interference screening identified XPO1 (exportin 1) among the 55 most vulnerable targets in multiple myeloma (MM). XPO1 encodes CRM1, a nuclear export protein. XPO1 expression increases with MM disease progression. Patients with MM have a higher expression of XPO1 compared with normal plasma cells (P<0.04) and to patients with monoclonal gammopathy of undetermined significance/smoldering MM (P<0.0001). The highest XPO1 level was found in human MM cell lines (HMCLs). A selective inhibitor of nuclear export compound KPT-276 specifically and irreversibly inhibits the nuclear export function of XPO1. The viability of 12 HMCLs treated with KTP-276 was significantly reduced. KPT-276 also actively induced apoptosis in primary MM patient samples. In gene expression analyses, two genes of probable relevance were dysregulated by KPT-276: cell division cycle 25 homolog A (CDC25A) and bromodomain-containing protein 4 (BRD4), both of which are associated with c-MYC pathway. Western blotting and reverse transcription-PCR confirm that c-MYC, CDC25A and BRD4 are all downregulated after treatment with KPT-276. KPT-276 reduced monoclonal spikes in the Vk*MYC transgenic MM mouse model, and inhibited tumor growth in a xenograft MM mouse model. A phase I clinical trial of an analog of KPT-276 is ongoing in hematological malignancies including MM.


Asunto(s)
Acrilamidas/farmacología , Transporte Biológico/efectos de los fármacos , Núcleo Celular/efectos de los fármacos , Estudio de Asociación del Genoma Completo , Carioferinas/genética , Mieloma Múltiple/genética , Receptores Citoplasmáticos y Nucleares/genética , Tiazoles/farmacología , Animales , Línea Celular Tumoral , Núcleo Celular/metabolismo , Perfilación de la Expresión Génica , Humanos , Carioferinas/efectos de los fármacos , Ratones , Interferencia de ARN , Receptores Citoplasmáticos y Nucleares/efectos de los fármacos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Ensayos Antitumor por Modelo de Xenoinjerto , Proteína Exportina 1
7.
Child Care Health Dev ; 39(3): 337-44, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-22676242

RESUMEN

BACKGROUND: Children with disabilities and their families experience environmental barriers in the school and community environments. There is a need to understand and appropriately measure environmental factors that influence activity and participation for disabled children. The purpose of this paper is to describe the adaptation process of the Craig Hospital Inventory of Environmental Factors (CHIEF) to make it suitable as a parent proxy measure for disabled children aged 2-12 years. METHODS: The adaptation process consisted of four steps using data from previous research conducted at CanChild: (i) analysis of item-total correlations from all items on the CHIEF; (ii) frequency of endorsement; (iii) determination of the representativeness of the questions; and (iv) correlations on selected items. Once the items were selected, a test-retest reliability study was conducted. RESULTS: The internal consistencies (α) for the time 1 and time 2 administrations were 0.76 and 0.78, respectively. Test-retest reliability of the questionnaire was ICC = 0.73 for the total product score. CONCLUSION: The 10-item CHIEF for Children-Parent Version is an acceptable, easy-to-complete and reliable measure of perceived environmental barriers for disabled children 2-12 years of age.


Asunto(s)
Niños con Discapacidad/rehabilitación , Ambiente , Medio Social , Accesibilidad Arquitectónica , Actitud Frente a la Salud , Niño , Preescolar , Niños con Discapacidad/psicología , Humanos , Padres/psicología , Apoderado , Psicometría , Reproducibilidad de los Resultados , Participación Social , Encuestas y Cuestionarios/normas
8.
Child Care Health Dev ; 39(5): 750-9, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22845889

RESUMEN

AIM: This study described the process used in developing an outcome measurement framework for system planning to improve services for children and youth with special needs and their families in a Canadian province. The study reports the results of several parent-completed measures, which would be useful in service planning as well as the acceptability and utility of these measures for use by families and service centres. METHODS/RESULTS: Development of a theoretical framework, consultation with key stakeholders, testing the utility of selected outcome measures and initial dissemination of results were critical elements in the successful development of an outcome system. Consultation with stakeholders confirmed use of the International Classification of Functioning, Disability and Health and the child-within-family-within community model as theoretical frameworks while building valuable partnerships and identifying potential barriers to implementation. Pilot testing showed three outcome measures were feasible for families to complete and the measures provided information about services for children that was valuable to families as well as service providers. Gaps in service delivery were identified and the need for better communication between service providers and communities to facilitate integrated services was highlighted. CONCLUSION: The findings from this study can be used to implement an outcome measurement system for children with special needs and may serve as a resource for international researchers who are working to develop valid tools as well as outcome systems that are useful for system planning.


Asunto(s)
Niños con Discapacidad/rehabilitación , Evaluación de Procesos y Resultados en Atención de Salud/métodos , Pediatría/normas , Adolescente , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Evaluación de Procesos y Resultados en Atención de Salud/organización & administración
9.
Leukemia ; 27(1): 66-74, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22847027

RESUMEN

Drugs that target the chief mediator of nuclear export, chromosome region maintenance 1 protein (CRM1) have potential as therapeutics for leukemia, but existing CRM1 inhibitors show variable potencies and a broad range of cytotoxic effects. Here, we report the structural analysis and antileukemic activity of a new generation of small-molecule inhibitors of CRM1. Designated selective inhibitors of nuclear export (SINE), these compounds were developed using molecular modeling to screen a small virtual library of compounds against the nuclear export signal (NES) groove of CRM1. The 2.2-Å crystal structure of the CRM1-Ran-RanBP1 complex bound to KPT-251, a representative molecule of this class of inhibitors, shows that the drug occupies part of the groove in CRM1 that is usually occupied by the NES, but penetrates much deeper into the groove and blocks CRM1-directed protein export. SINE inhibitors exhibit potent antileukemic activity, inducing apoptosis at nanomolar concentrations in a panel of 14 human acute myeloid leukemia (AML) cell lines representing different molecular subtypes of the disease. When administered orally to immunodeficient mice engrafted with human AML cells, KPT-251 had potent antileukemic activity with negligible toxicity to normal hematopoietic cells. Thus, KPT-SINE CRM1 antagonists represent a novel class of drugs that warrant further testing in AML patients.


Asunto(s)
Transporte Activo de Núcleo Celular/efectos de los fármacos , Antineoplásicos/farmacología , Carioferinas/química , Leucemia Mieloide Aguda/tratamiento farmacológico , Señales de Exportación Nuclear , Proteínas Nucleares/metabolismo , Receptores Citoplasmáticos y Nucleares/química , Proteína de Unión al GTP ran/metabolismo , Animales , Antineoplásicos/química , Apoptosis , Western Blotting , Ciclo Celular , Núcleo Celular/metabolismo , Proliferación Celular , Células Cultivadas , Cristalización , Cristalografía por Rayos X , Femenino , Células Madre Hematopoyéticas , Humanos , Subunidad gamma Común de Receptores de Interleucina/fisiología , Carioferinas/metabolismo , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patología , Ratones , Ratones Endogámicos NOD , Ratones SCID , Proteínas Nucleares/química , Unión Proteica , Receptores Citoplasmáticos y Nucleares/metabolismo , Bibliotecas de Moléculas Pequeñas , Ensayos Antitumor por Modelo de Xenoinjerto , Proteína de Unión al GTP ran/química , Proteína Exportina 1
10.
Heredity (Edinb) ; 103(1): 5-14, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19367316

RESUMEN

The genus Silene, studied by Darwin, Mendel and other early scientists, is re-emerging as a system for studying interrelated questions in ecology, evolution and developmental biology. These questions include sex chromosome evolution, epigenetic control of sex expression, genomic conflict and speciation. Its well-studied interactions with the pathogen Microbotryum has made Silene a model for the evolution and dynamics of disease in natural systems, and its interactions with herbivores have increased our understanding of multi-trophic ecological processes and the evolution of invasiveness. Molecular tools are now providing new approaches to many of these classical yet unresolved problems, and new progress is being made through combining phylogenetic, genomic and molecular evolutionary studies with ecological and phenotypic data.


Asunto(s)
Ecología , Evolución Molecular , Modelos Biológicos , Silene/genética , Basidiomycota/fisiología , Cromosomas de las Plantas/genética , Enfermedades de las Plantas/microbiología , Silene/microbiología , Silene/fisiología
11.
Heredity (Edinb) ; 100(6): 574-80, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18301440

RESUMEN

A variety of questions in population and evolutionary biology are studied using chloroplast DNA (cpDNA). The presumed maternal inheritance in angiosperms allows for certain assumptions and calculations to be made when studying plant hybridization, phylogeography, molecular systematics and seed dispersal. Further, the placement of transgenes in the chloroplast to lessen the probability of 'escape' to weedy relatives has been proposed since such genes would not move through pollen. In many studies, however, strict maternal inheritance is assumed but not tested directly, and some studies may have sample sizes too small to be able to detect rare paternal leakage. Here, we study the inheritance of cpDNA simple sequence repeats in 323 offspring derived from greenhouse crosses of the rare sunflower Helianthus verticillatus Small. We found evidence for rare chloroplast paternal leakage and heteroplasmy in 1.86% of the offspring. We address the question of whether one can extrapolate the mode of chloroplast transmission within a genus by comparing our results to the findings of another sunflower species study. The findings of occasional paternal transmission of the chloroplast genome are discussed in the framework of using these markers in studies of population and evolutionary biology both in Helianthus and other angiosperms.


Asunto(s)
ADN de Cloroplastos/genética , Herencia Extracromosómica , Helianthus/genética , Cloroplastos , Cruzamientos Genéticos
12.
Mol Ecol ; 15(9): 2345-55, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16842410

RESUMEN

Determining the genetic structure of isolated or fragmented species is of critical importance when planning a suitable conservation strategy. In this study, we use nuclear and chloroplast SSRs (simple sequence repeats) to investigate the population genetics of an extremely rare sunflower, Helianthus verticillatus Small, which is known from only three locations in North America. We investigated levels of genetic diversity and population structure compared to a more common congener, Helianthus angustifolius L., using both nuclear and chloroplast SSRs. We also investigated its proposed hybrid origin from Helianthus grosseserratus Martens and H. angustifolius. Twenty-two nuclear SSRs originating from the cultivated sunflower (Helianthus annuus L.) expressed sequence tag (EST) database, and known to be transferable to H. verticillatus and its putative parental taxa, were used in this study thereby allowing for statistical control of locus-specific effects in population genetic analyses. Despite its rarity, H. verticillatus possessed significantly higher levels of genetic diversity than H. angustifolius at nuclear loci and equivalent levels of chloroplast diversity. Significant levels of population subdivision were observed in H. verticillatus but of a magnitude comparable to that of H. angustifolius. Inspection of multilocus genotypes also revealed that clonal spread is highly localized. Finally, we conclude that H. verticillatus is not of hybrid origin as it does not exhibit a mixture of parental alleles at nuclear loci, and it does not share a chloroplast DNA haplotype with either of its putative parents.


Asunto(s)
Biodiversidad , Variación Genética/genética , Helianthus/genética , Secuencia de Bases , Quimera , Cloroplastos/genética , Expresión Génica , Genética de Población , Helianthus/clasificación
13.
Heredity (Edinb) ; 95(1): 50-8, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15829984

RESUMEN

Gynodioecy refers to the co-occurrence of females and hermaphrodites in the same population. In many gynodioecious plants, sex is determined by an epistatic interaction between mitochondrial and nuclear genes, resulting in intragenomic evolutionary conflict, should the mitochondrial genome be maternally inherited. While maternal inheritance of the mitochondrial genome is common in angiosperms, few gynodioecious species have been studied. Here, the inheritance of the mitochondrial genes atpA and coxI was studied in 318 Silene vulgaris individuals distributed among 23 crosses. While maternal inheritance was indicated in 96% of the individuals studied, one or more individuals from each of four sib groups displayed a genotype that was identical to the father, or that did not match either parent. Given evidence that inheritance is not strictly maternal, it was hypothesized that some individuals could carry a mixture of maternally and paternally derived copies of the mitochondrial genome, a condition known as heteroplasmy. Since heteroplasmy might be difficult to detect should multiple versions of the mitochondrial genome co-occur in highly unequal copy number, a method was devised to amplify low-copy number forms of atpA differentially. Evidence for heteroplasmy was found in 23 of the 99 individuals studied, including cases in which the otherwise cryptic form of atpA matched the paternal genotype. The distribution of shared nucleotide sequence polymorphism among atpA haplotypes and the results of a population survey of the joint distribution of atpA and coxI haplotypes across individuals supports the hypothesis that heteroplasmy facilitates formation of novel mitochondrial genotypes by recombination.


Asunto(s)
ADN Mitocondrial , Silene/genética , Trastornos del Desarrollo Sexual , Genoma , Genotipo , Haplotipos , Patrón de Herencia
14.
Mol Ecol ; 12(12): 3227-35, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14629341

RESUMEN

Silene vulgaris was introduced into North America sometime prior to 1800. In order to document the population structure that has developed since that time, collections were made from 56 local populations distributed among 9 geographical regions in eastern North America. Individual plants were characterized for chloroplast DNA (cpDNA) haplotype by restriction fragment size analysis of four noncoding regions of cpDNA amplified by polymerase chain reaction. A total of 19 cpDNA haplotypes were detected using this method. The overall gene diversity of 0.85 is quite similar to the diversity detected in these same regions of cpDNA in a previously published sample of S. vulgaris taken from across much of Europe. The spatial distribution of the North American cpDNA diversity was quantified by hierarchical F-statistics that partitioned the genetic variance into variation among local populations within regions, and variation among regions. The average FST among populations within regions was 0.66 and the FST among regions was 0.09. The among-region variation was due to both differences among regions in the frequency of two most common haplotypes, and to the presence of a number of region-specific haplotypes. In order to test for isolation by distance at the regional level, FST values were calculated for all possible pairs of regions, and regressed against the geographical distance between those regions. There was no evidence for isolation by distance. It is suggested that the local population structure is generated by recent extinction/colonization dynamics, and that the among-region structure reflects demographic events associated with range expansion following introduction to North America.


Asunto(s)
Demografía , Variación Genética , Geografía , Silene/genética , ADN de Cloroplastos/genética , Electroforesis en Gel de Agar , Genética de Población , Haplotipos/genética , América del Norte , Polimorfismo de Longitud del Fragmento de Restricción , Dinámica Poblacional
15.
Mol Ecol ; 12(3): 777-87, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12675832

RESUMEN

It has been suggested that the dynamics of chloroplast DNA (cpDNA) or mitochondrial DNA (mtDNA) genetic markers used in studies of plant populations could be influenced by natural selection acting elsewhere in the genome. This could be particularly true in gynodioecious plants if cpDNA or mtDNA genetic markers are in gametic disequilibrium with genes responsible for sex expression. In order to investigate this possibility, a natural population of the gynodioecious plant Silene vulgaris was used to study associations among mtDNA haplotype, cpDNA haplotype, sex and some components of fitness through seed. Individuals were sampled for mtDNA and cpDNA haplotype as determined using restriction fragment length polymorphism (RFLP) methods, sex (female or hermaphrodite), fruit number, fruit set, seeds/fruit and seed germination. The sex of surviving germinating seeds was also noted. All individuals in the population fell into one of two cytoplasmic categories, designated haplotypes f and g by a unique electrophoretic signature in both the mtDNA and cpDNA. The subset of the population carrying haplotype g included a significantly higher proportion of females when compared with the sex ratio of the subset carrying the f haplotype. Haplotype g had a significantly higher fitness when measured by fruit number, fruit set and seeds/fruit, whereas haplotype f had significantly higher fitness when measured by seed germination. Offspring of individuals carrying haplotype g included a significantly greater proportion of females when compared with offspring of individuals carrying the f haplotype. Other studies of gynodioecious plants have shown that females generally have higher fitness through seed than hermaphrodites, but in this study not all fitness differences between haplotypes could be predicted from differences in haplotype-specific sex ratio alone. Rather, some differences in haplotype-specific fitness were due to differences in fitness between individuals of the same sex, but carrying different haplotypes. The results are discussed with regard to the potential for hitchhiking selection to influence the dynamics of the noncoding regions used to designate the cpDNA and mtDNA haplotypes.


Asunto(s)
ADN de Cloroplastos/genética , ADN Mitocondrial/genética , Semillas/fisiología , Silene/fisiología , Southern Blotting , ADN de Cloroplastos/química , ADN Mitocondrial/química , Marcadores Genéticos/genética , Germinación/genética , Germinación/fisiología , Haplotipos , Hojas de la Planta/genética , Reacción en Cadena de la Polimerasa , Semillas/genética , Silene/genética , Virginia
16.
Heredity (Edinb) ; 90(2): 181-6, 2003 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-12634825

RESUMEN

Small local populations of Silene alba, a short-lived herbaceous plant, were sampled in 1994 and again in 1999. Sampling included estimates of population size and genetic diversity, as measured at six polymorphic allozyme loci. When averaged across populations, there was very little change between samples (about three generations) in population size, measures of within-population genetic diversity such as number of alleles or expected heterozygosity, or in the apportionment of genetic diversity within and among populations as measured by F(st). However, individual populations changed considerably, both in terms of numbers of individuals and genetic composition. Some populations doubled in size between samples, while others shrank by more than 75%. Similarly, expected heterozygosity and allele number increased by more than two-fold in individual populations and decreased by more than three-fold in others. When population-specific change in number and change in measures of genetic diversity were considered together, significant positive correlations were found between the demographic and genetic variables. It is speculated that some populations were released from the demographic consequences of inbreeding depression by gene flow.


Asunto(s)
Silene/genética , Alelos , Frecuencia de los Genes , Variación Genética
17.
Eur Respir J Suppl ; 39: 45s-51s, 2003 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12572701

RESUMEN

Screening should be considered in lung cancer, more than any other cancer. Not only is the disease highly fatal, essentially incurable, when diagnosed on the prompting of symptoms and/or clinical signs, but its occurrence is also highly concentrated in identifiably high-risk persons. The degree of usefulness of computed tomography (CT)-based screening for lung cancer must be thought of in reference to a particular, presumably optimal, regimen of pursuing early stage diagnosis. This is an algorithm that begins with the initial test ("screening CT") and ends in either discontinuation of the diagnostic pursuit or in diagnosis of lung cancer. A carefully developed, extensively pilot tested and critically reviewed, updated protocol for CT-based screening for lung cancer is presented here. Its implementation is addressed, together with quality assurance. Finally, the associated curability rate for lung cancer is addressed in the light of what is known or can be surmised from evidence already available. However, recommendation for or against screening requires further information. Principally, the patients risk for lung cancer (in the near future) and the patients life expectancy (when spared of death from lung cancer). These two factors influence when, if ever, to begin screening, and if it is initiated, when to discontinue it. Finally, cost-effectiveness of the screening program should also be considered.


Asunto(s)
Neoplasias Pulmonares/diagnóstico por imagen , Guías de Práctica Clínica como Asunto , Tomografía Computarizada Espiral/normas , Humanos , Garantía de la Calidad de Atención de Salud , Sensibilidad y Especificidad
18.
Int J Gynecol Cancer ; 12(6): 745-8, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12445253

RESUMEN

This report summarizes our experience with the combination of mesna, doxorubicin, ifosfamide, and dacarbazine (MAID) for patients with gynecological sarcomas. We reviewed the records of all patients who had received the MAID regimen for a gynecological sarcoma between 1993 and 2000. The MAID regimen was administered intravenously every 4 weeks in the hospital as follows: (1) mesna 1500 mg/m2/day x 4 days; (2) doxorubicin 15 mg/m2/day x 3 days; (3) ifosfamide 1500 mg/m2/day x 3 days; (4) dacarbazine 250 mg/m2/day x 3 days. The results of treatment with MAID were disappointing. Overall, the response rate was 9% with one complete response and one partial response (both in patients with uterine leiomyosarcoma). We did not observe any responses among the patients with carcinosarcomas of either ovarian or uterine origin. The median progression-free interval and survival were 11 months and 29 months, respectively. This regimen was associated with substantial toxicity (including a death from neutropenic sepsis) as well as high cost and inconvenience due to the requirement for inpatient administration. Although our study contains a limited number of patients with a variety of gynecological sarcomas, our review has led us to discontinue using MAID. It remains to be established if any combination chemotherapy regimen is better than single agent treatment.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de los Genitales Femeninos/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Carcinosarcoma/tratamiento farmacológico , Carcinosarcoma/mortalidad , Carcinosarcoma/patología , Dacarbazina/administración & dosificación , Supervivencia sin Enfermedad , Doxorrubicina/administración & dosificación , Esquema de Medicación , Femenino , Neoplasias de los Genitales Femeninos/mortalidad , Neoplasias de los Genitales Femeninos/patología , Humanos , Ifosfamida/administración & dosificación , Leiomiosarcoma/tratamiento farmacológico , Leiomiosarcoma/mortalidad , Leiomiosarcoma/patología , Registros Médicos , Mesna/administración & dosificación , Persona de Mediana Edad , Estadificación de Neoplasias , New York , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/mortalidad , Neoplasias Ováricas/patología , Estudios Retrospectivos , Análisis de Supervivencia , Resultado del Tratamiento , Neoplasias Uterinas/tratamiento farmacológico , Neoplasias Uterinas/mortalidad , Neoplasias Uterinas/patología , Neoplasias de la Vulva/tratamiento farmacológico , Neoplasias de la Vulva/mortalidad , Neoplasias de la Vulva/patología
19.
Clin Sci (Lond) ; 101(5): 507-13, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11672456

RESUMEN

Heightened systemic oxidative stress is increasingly recognized as a feature of cystic fibrosis (CF). The consequences of long-term exposure to free radical attack include a predisposition to diseases such as cancer and atherosclerosis. An increased incidence of malignancy among adult patients with CF has been reported, but the absence of atherosclerotic disease is well described. The aim of the present study was to assess endothelial function in vivo and relate this to the potential of serum from patients with CF to induce oxidative-mediated damage in cultured human endothelial cells. A group of 11 CF patients was matched with a group of healthy volunteers with regard to age and sex. Endothelial function was assessed as endothelium-dependent and -independent vasodilation by measuring forearm blood flow in response to infused acetylcholine and sodium nitroprusside respectively. Confluent monolayers of cultured human endothelial cells were exposed to serum from CF patients and control subjects. Following exposure, cell death was assessed by lactate dehydrogenase release, and the degree of lipid peroxidation in the membrane was assessed by measuring the content of lipid hydroperoxides, malondialdehyde and 4-hydroxynonenal. Endothelial monolayers exposed to serum from CF patients released significantly less lactate dehydrogenase following exposure than those exposed to serum from healthy controls (1.8% and 3.0% respectively; mean difference -1.2%; 95% confidence intervals -1.9% to -0.1%; P<0.05) and contained significantly less 4-hydroxynonenal (0.75 and 3.41 micromol/g of protein respectively; mean difference -2.66 micromol/g; 95% confidence intervals -5.10 to -0.22 micromol/g; P<0.05). There was no significant difference between patients and controls in the extent of serum-induced membrane peroxidation, as assessed by malondialdehyde or lipid hydroperoxides, or in endothelial function, as assessed by forearm blood flow. In conclusion, despite evidence for heightened systemic oxidative stress in CF, patients displayed no impairment of endothelial function, and their serum caused significantly less damage to human endothelial cells than that from matched controls.


Asunto(s)
Fibrosis Quística/fisiopatología , Endotelio Vascular/fisiopatología , Estrés Oxidativo/fisiología , Adolescente , Adulto , Aorta/patología , Área Bajo la Curva , Estudios de Casos y Controles , Células Cultivadas , Cromatografía Líquida de Alta Presión , Medios de Cultivo , Fibrosis Quística/sangre , Fibrosis Quística/patología , Endotelio Vascular/citología , Humanos , L-Lactato Deshidrogenasa/metabolismo , Peroxidación de Lípido/fisiología , Masculino , Pletismografía , Espectrofotometría , Estadísticas no Paramétricas , Vitamina E/sangre
20.
Cancer ; 92(1): 153-9, 2001 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-11443621

RESUMEN

BACKGROUND: The Early Lung Cancer Action Project (ELCAP) was designed to evaluate the usefulness of annual computed tomography (CT) screening for lung carcinoma. With the baseline results having been reported previously, the focus of the current study was on the early results of the repeat screenings. METHODS: A cohort of 1000 high-risk individuals was recruited for baseline and annual repeat CT screening. At last follow-up, a total of 1184 annual repeat screenings had been performed. A positive result from the screening test was defined as newly detected, one to six noncalcified pulmonary nodules with interim growth. The diagnostic workup of the individuals was guided by recommendations supplied by the ELCAP investigators to the collaborating clinicians. RESULTS: Of the 1184 repeat CT screenings, the test result was positive in 30 (2.5%). In 2 of these 30 cases, the individual died (of an unrelated cause) before diagnostic workup and the nodule(s) resolved in another 12 individuals. In the remaining 16 individuals, the absence of further growth was documented by repeat CT in 8 individuals and further growth was documented in the remaining 8 individuals. All eight individuals with further nodular growth underwent biopsy and malignancy was diagnosed in seven. Six of these seven malignancies were nonsmall cell carcinomas (five of which were Stage IA and one of which was Stage IIIA) and the one small cell carcinoma was found to be of limited stage. The median size dimension of these malignancies was 8 mm. In another two subjects, symptoms prompted the interim diagnosis of lung carcinoma. Neither of these malignancies was nodule-associated but rather were endobronchial; one was a Stage IIB nonsmall cell carcinoma and the other was a small cell carcinoma of limited stage. CONCLUSIONS: False-positive screening test results are uncommon and usually manageable without biopsy; compared with no screening, such screenings permit diagnosis at substantially earlier and thus more curable stages. Annual repetition of CT screening is sufficient to minimize symptom-prompted interim diagnoses of nodule-associated malignancies.


Asunto(s)
Neoplasias Pulmonares/diagnóstico , Tamizaje Masivo , Anciano , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tomografía Computarizada por Rayos X
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