RESUMEN
A panel of toxicology, mode of action (MOA), and cancer risk assessment experts was engaged to derive no-significant-risk-levels (NSRLs) for three lower acrylates: methyl acrylate (MA), ethyl acrylate (EA), and 2-ethylhexyl acrylate (2EHA) using the best available science, data, and methods. The review was structured as a five-round, modified Delphi format, a systematic process for collecting independent and deliberative input from panel members, and it included several procedural elements to reduce potential sources of bias and groupthink. Input from the panel for key decisions in the dose-response assessments resulted in NSRL values of 530 µg/day (330-800 µg/day), 640 µg/day (280-670 µg/day), and 1700 µg/day (1300-2700 µg/day) for MA, EA, and 2EHA, respectively. Novel to this approach were the use of nonneoplastic lesions reported at point of contact where tumors have been reported in laboratory rodents, along with nonlinear extrapolation to low doses (uncertainty factor approach) based upon panel recommendations. Confidence in these values is considered medium to high for exposures applied to the routes of exposure tested (inhalation for MA and EA, dermal for 2EHA), but confidence is considered lower when applied to other routes of exposure.
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Acrilatos , Roedores , Animales , Acrilatos/toxicidadRESUMEN
An international panel of experts was engaged to assess the cancer weight of evidence (WOE) for three lower acrylates: methyl acrylate, ethyl acrylate, and 2-ethylhexyl acrylate. The review was structured as a three-round, modified Delphi format, a systematic process for collecting independent and deliberative input from panel members, and it included procedural elements to reduce bias and groupthink. Based upon the available science, the panel concluded: (1) The MOA for point of contact tumors observed in rodent cancer bioassays that is best supported by available data involves increased cell replication by cytotoxicity and regenerative proliferation; (2) The WOE supports a cancer classification of "Not likely to be carcinogenic to humans" a conclusion that is more in line with an IARC classification of Group 3 rather than Group 2 B; (3) Quantitative cancer potency values based on rodent tumor data are not required for these chemicals; and (4) Human health risk assessment for these chemicals should instead rely on non-cancer, precursor endpoints observed at the point of contact (e.g., hyperplasia). The degree of consensus (consensus scores of 0.84-0.91 out of a maximum score of 1) and degree of confidence (7.7-8.7 out of a maximum score of 10) in the WOE conclusions is considered high.
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Neoplasias , Humanos , Neoplasias/inducido químicamente , Carcinógenos/toxicidad , Carcinogénesis , Consenso , Acrilatos/toxicidadRESUMEN
OBJECTIVE: To characterize the literature, reported enablers, and gaps on the use of patient experience feedback for person-centered rehabilitation quality improvement and codesign activities. DESIGN: Scoping Review. DATA SOURCES: Scientific databases (PubMed, CINAHL, Rehabdata, Scopus, Web of Science, ProQuest), website searches (e.g. Beryl Institute), snowballing, and key-informant recommendations. METHODS: Two independent reviewers performed title and abstract screenings and full-text reviews. Eligibility focused on English-language, peer-reviewed (all time) and gray literature (last five years) that used patient experience feedback in rehabilitation improvement activities. The aims, settings, methods, findings, implications, and reported limitations were extracted, followed by content analyses identifying reported enablers and gaps. RESULTS: Among the 901 unique references and 52 full texts reviewed, ten were included: four used patient experience surveys for improving patient experiences; six used codesign methodologies to engage patient feedback in service improvement activities. Implementation enablers included securing managerial support, having a structured methodology and facilitator, using efficient processes, engaging staff experiences, and using appreciative inquiry. Reported study gaps included limited follow-up, low sample sizes, analytical limitations, lack of reported limitations, or narrow range of perspectives (e.g. not from people with severe impairments). CONCLUSION: Few examples of the use of patient experience feedback in quality improvement or codesign activities were found in the rehabilitation literature. Patient experience improvement activities relied exclusively on retrospective survey data, which were not combined with often more actionable forms (e.g. qualitative, real time) of patient experience feedback. Further research might consider design of activities that collect and use patient experience feedback for rehabilitation service improvements.
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Evaluación del Resultado de la Atención al Paciente , Mejoramiento de la Calidad , Humanos , Retroalimentación , Estudios RetrospectivosRESUMEN
A comprehensive study has been undertaken into a 13th century Coptic-Byzantine icon from the St. Mercurius Church, St. Mercurius monastery, Old Cairo, Egypt. The layered structure, pigment composition and varnish identification were revealed by means of optical and Raman microscopy and gas chromatography-mass spectrometry (GC-MS). The structure of the icon comprised six layers; wooden panel, canvas, white ground, two bole layers and a single paint layer. Azurite (2CuCO(3) x Cu(OH)(2)), cinnabar (mercuric (II) sulfide alpha-HgS), yellow ochre (Fe(2)O(3) x H(2)O), hydromagnesite Mg(5)(CO(3))(4)(OH)(2) x 4 H(2)O and lamp black (carbon, C) are the pigments identified in the icon. The green paint area is of interest as it is applied neither with a green pigment nor with a mixture of a blue and yellow pigment. Instead, a yellow layer of dammar resin was applied on top of blue azurite to obtain the green colour. Pinaceae sp. resin mixed with drying oil was used as a protective varnish.
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Cromatografía de Gases y Espectrometría de Masas , Pintura/análisis , Pinturas/historia , Pinaceae/química , Resinas de Plantas/análisis , Espectrometría Raman , Bizancio , Colorantes/análisis , Historia Medieval , Aceites/análisisRESUMEN
Extramammary Paget's disease (EMPD) is a rare skin cancer of the genital region in which cancer cells with enlarged nuclei and pale cytoplasm are scattered singly in the affected epidermis. These cancer cells, called Paget cells, contain mucin, which is never found in normal epidermis. The oligosaccharide side chains of Paget cell mucin end with sialic acid. Sialic acid is easily detected by zirconyl haematoxylin or alcian blue. The other sugars in the oligosaccharide chains can be detected by the periodic acid-Shiff reaction. Rarely, the diagnosis of EMPD is complicated by the absence of mucin from the Paget cells. We have examined such an atypical case. The oligosaccharide side chains, including the sialic acids, are absent. In both this case and a typical case, the Paget cells contain epithelial membrane antigen mucin (MUC1) core protein and usually contain gastric surface-type mucin (MUC5AC) core protein, which can be stained by antibodies. Since neither core protein is found in normal epidermis, epithelial membrane antigen core protein may be the most reliable diagnostic marker for extramammary Paget's disease. In both the atypical case and the typical case of Paget's disease, some cells that look like keratinocytes contain mucin core proteins. These may be incipient Paget cells. We suggest that using th epithelial membrane antigen core protein as a marker for the true extent of extramammary Paget's disease could facilitate complete excision and reduce the rate of recurrence.
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Mucinas/metabolismo , Enfermedad de Paget Extramamaria/diagnóstico , Enfermedad de Paget Extramamaria/metabolismo , Humanos , InmunohistoquímicaRESUMEN
The WASID trial showed no advantage of warfarin over aspirin for preventing the primary endpoint of ischemic stroke, brain hemorrhage, or vascular death. In analyses of selected subgroups, there was no definite benefit from warfarin. Warfarin reduced the risk of the primary endpoint among patients with basilar artery stenosis, but there was no reduction in stroke in the basilar artery territory or benefit for vertebral artery stenosis or posterior circulation disease in general.
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Aspirina/uso terapéutico , Enfermedades Arteriales Cerebrales/tratamiento farmacológico , Enfermedades Arteriales Cerebrales/mortalidad , Medición de Riesgo/métodos , Warfarina/uso terapéutico , Anciano , Anciano de 80 o más Años , Antiinflamatorios no Esteroideos/uso terapéutico , Anticoagulantes/uso terapéutico , Enfermedades Arteriales Cerebrales/diagnóstico , Constricción Patológica/diagnóstico , Constricción Patológica/tratamiento farmacológico , Constricción Patológica/mortalidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Análisis de Supervivencia , Tasa de Supervivencia , Resultado del Tratamiento , Estados Unidos/epidemiologíaRESUMEN
OBJECTIVE: To assess the efficacy of carotid endarterectomy for stroke prevention in asymptomatic and symptomatic patients with internal carotid artery stenosis. Additional clinical scenarios, such as use of endarterectomy combined with cardiac surgery, are also reviewed. METHODS: The authors selected nine important clinical questions. A systematic search was performed for articles from 1990 (the year of the last statement) until 2001. Additional articles from 2002 through 2004 were included using prespecified criteria. Two reviewers also screened for other relevant articles from 2002 to 2004. Case reports, review articles, technical studies, and single surgeon case series were excluded. RESULTS: For several questions, high quality randomized clinical trials had been completed. Carotid endarterectomy reduces the stroke risk compared to medical therapy alone for patients with 70 to 99% symptomatic stenosis (16% absolute risk reduction at 5 years). There is a smaller benefit for patients with 50 to 69% symptomatic stenosis (absolute risk reduction 4.6% at 5 years). There is a small benefit for asymptomatic patients with 60 to 99% stenosis if the perioperative complication rate is low. Aspirin in a dose of 81 to 325 mg per day is preferred vs higher doses (650 to 1,300 mg per day) in patients undergoing endarterectomy. CONCLUSIONS: Evidence supports carotid endarterectomy for severe (70 to 99%) symptomatic stenosis (Level A). Endarterectomy is moderately useful for symptomatic patients with 50 to 69% stenosis (Level B) and not indicated for symptomatic patients with <50% stenosis (Level A). For asymptomatic patients with 60 to 99% stenosis, the benefit/risk ratio is smaller compared to symptomatic patients and individual decisions must be made. Endarterectomy can reduce the future stroke rate if the perioperative stroke/death rate is kept low (<3%) (Level A). Low dose aspirin (81 to 325 mg) is preferred for patients before and after carotid endarterectomy to reduce the rate of stroke, myocardial infarction, and death (Level A).
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Estenosis Carotídea/cirugía , Endarterectomía Carotidea/estadística & datos numéricos , Accidente Cerebrovascular/prevención & control , Aspirina/administración & dosificación , Causalidad , Ensayos Clínicos como Asunto/estadística & datos numéricos , Relación Dosis-Respuesta a Droga , Endarterectomía Carotidea/efectos adversos , Endarterectomía Carotidea/mortalidad , Medicina Basada en la Evidencia , Femenino , Humanos , Masculino , Mortalidad/tendencias , Selección de Paciente , Inhibidores de Agregación Plaquetaria/administración & dosificación , Complicaciones Posoperatorias/etiología , Medición de Riesgo , Resultado del TratamientoRESUMEN
Hair removed from archaeological burials can tell us a lot about the diet and lifestyle of our ancestors--information that may survive because of the unique biology of hair formation. But hair is also biodegradable and the effects of time and burial conditions can result in conflicting evidence of past lives.
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Arqueología/métodos , Cabello/química , Cabello/anatomía & histología , Cabello/metabolismo , Color del Cabello , HumanosRESUMEN
The spindle checkpoint delays the onset of anaphase until all pairs of sister chromatids are attached to the mitotic spindle. The checkpoint could monitor the attachment of microtubules to kinetochores, the tension that results from the two sister chromatids attaching to opposite spindle poles, or both. We tested the role of tension by allowing cells to enter mitosis without a prior round of DNA replication. The unreplicated chromatids are attached to spindle microtubules but are not under tension since they lack a sister chromatid that could attach to the opposite pole. Because the spindle checkpoint is activated in these cells, we conclude that the absence of tension at the yeast kinetochore is sufficient to activate the spindle checkpoint in mitosis.
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Proteínas Portadoras , Cinetocoros/fisiología , Proteínas de Saccharomyces cerevisiae , Transducción de Señal , Huso Acromático/fisiología , Proteínas de Unión al Calcio/genética , Proteínas de Unión al Calcio/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Proteínas Mad2 , Proteínas Nucleares , SaccharomycetalesRESUMEN
Neuropsychological testing has been used in court cases all over the United States, as testimony to provide evidence of whether or not a person has a traumatic brain injury. It has, however, been scrutinized for its admissibility in court, but recognized for objectivity in successfully documenting and proving deficits in people with traumatic brain injuries. The trial court is used as a gatekeeper, and may chose to perform assessments of the tests themselves, for validity of sensitivity, specificity, reliability and validity in determining whether a neuropsychological test may be used as testimony in a court case.
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Conmoción Encefálica/diagnóstico , Lesión Encefálica Crónica/diagnóstico , Testimonio de Experto/legislación & jurisprudencia , Pruebas Neuropsicológicas , Conmoción Encefálica/psicología , Lesión Encefálica Crónica/psicología , Control de Acceso/legislación & jurisprudencia , Humanos , Responsabilidad Legal , Anamnesis , Registros Médicos , Pruebas Neuropsicológicas/normas , Reproducibilidad de los Resultados , Estados UnidosRESUMEN
Attendees indicated that the workshop was beneficial and that the opportunity to communicate with faculty representing 23 programs accredited by EHAC and nine programs not accredited by EHAC was extremely useful. There was general agreement on a number of points: There is a need for undergraduate environmental health programs to collaborate on matters related to distance learning. Topics related to women, gender, diversity, ethics, and international environmental health should be incorporated into the environmental health curriculum. There are no major problems with current EHAC curricular guidelines, but the guidelines should be evaluated on a regular basis. Field experience or internship is an essential component in the academic preparation of undergraduate environmental health students. There is a significant need for increased funding for undergraduate environmental health programs. There is a need to increase the visibility and recognition of environmental health programs. There is a need to solidify ties with traditional partners and to establish new linkages at the local, regional, and national levels in the government, community, and private sector. It is essential that undergraduate faculty communicate with each other on matters relating to the preparation of environment health practitioners. There is a need for an association of undergraduate academic programs to provide leadership and a focal point for identification and resolution of issues common to all. The establishment of an association was viewed as the most practical and effective way to address these issues and to pursue related opportunities.
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Educación Profesional , Salud Ambiental , Acreditación , Movilidad Laboral , Curriculum , Educación Continua , Educación a Distancia , Femenino , Grupos Focales , Salud Global , Humanos , Relaciones Interinstitucionales , Masculino , Estados Unidos , Salud de la MujerRESUMEN
BACKGROUND AND PURPOSE: The relationship between alcohol consumption and cerebral infarction remains uncertain, and few studies have investigated whether the relationship varies by alcohol type or is present in young adults. We examined the relationship between alcohol consumption, beverage type, and ischemic stroke in the Stroke Prevention in Young Women Study. METHODS: All 59 hospitals in the greater Baltimore-Washington area participated in a population-based case-control study of stroke in young women. Case patients (n=224) were aged 15 to 44 years with a first cerebral infarction, and control subjects (n=392), identified by random-digit dialing, were frequency matched by age and region of residence. The interview assessed lifetime alcohol consumption and consumption and beverage type in the previous year, week, and day. ORs were obtained from logistic regression models controlling for age, race, education, and smoking status, with never drinkers as the referent. RESULTS: Alcohol consumption, up to 24 g/d, in the past year was associated with fewer ischemic strokes (<12 g/d: OR 0.57, 95% CI 0. 38 to 0.86; 12 to 24 g/d: OR 0.38, 95% CI 0.17 to 0.86; >24 g/d: OR 0.95, 95% CI 0.43 to 2.10) in comparison to never drinking. Analyses of beverage type (beer, wine, liquor) indicated a protective effect for wine consumption in the previous year (<12 g/wk: OR 0.58, 95% CI 0.35 to 0.97; 12 g/wk to <12 g/d: OR 0.55, 95% CI 0.28 to 1.10; >/=12 g/d: OR 0.92, 95% CI 0.23 to 3.64). CONCLUSIONS: Light to moderate alcohol consumption appears to be associated with a reduced risk of ischemic stroke in young women.
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Consumo de Bebidas Alcohólicas/epidemiología , Bebidas Alcohólicas/clasificación , Infarto Cerebral/epidemiología , Infarto Cerebral/prevención & control , Adolescente , Adulto , Consumo de Bebidas Alcohólicas/sangre , Bebidas Alcohólicas/estadística & datos numéricos , Índice de Masa Corporal , Estudios de Casos y Controles , Infarto Cerebral/sangre , Colesterol/sangre , HDL-Colesterol/sangre , Comorbilidad , Delaware/epidemiología , District of Columbia/epidemiología , Femenino , Humanos , Entrevistas como Asunto , Modelos Logísticos , Maryland/epidemiología , Oportunidad Relativa , Pennsylvania/epidemiología , Vigilancia de la Población , Medición de Riesgo , Factores de RiesgoRESUMEN
The aim of this study was to determine HIV-1 V3 sequences, in vitro biological characteristics and co-receptor usage of virus isolates from Tanzania. Virus was isolated from 14 of 17 samples investigated. Four of the isolates induced syncytia in MT-2 cells and used the CXCR4 co-receptor, while the remaining 10 isolates used the CCR5 co-receptor characteristic of non-MT-2 tropic viruses. One of the four MT-2 tropic isolates also used the CCR5 and CCR3 co-receptors. Proviral DNA was detected in all 14 isolates and PCR products were subjected to DNA sequencing. Unambiguous V3 amino acid sequences were obtained from 11 amplificates. Phylogenetic analysis indicated that these sequences were divergent and clustered in HIV-1 subtypes A, C or D. Sequences from the viruses that induced syncytia in MT-2 cells presented characteristic V3 phenotype-associated amino acids. Results of co-receptor analysis are in concordance with the isolate phenotype as determined by replication and induction of syncytia in MT-2 cells. The considerable diversity illustrated by a limited number of isolates from Tanzania is in accordance with reports from other regions of Africa.
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Proteína gp120 de Envoltorio del VIH/genética , Infecciones por VIH/virología , VIH-1/genética , Fragmentos de Péptidos/genética , Receptores CXCR4/metabolismo , Adolescente , Adulto , Secuencia de Aminoácidos , Animales , Efecto Citopatogénico Viral , ADN Viral/genética , ADN Viral/aislamiento & purificación , Variación Genética , Células Gigantes/virología , Proteína gp120 de Envoltorio del VIH/metabolismo , VIH-1/clasificación , VIH-1/aislamiento & purificación , Humanos , Persona de Mediana Edad , Datos de Secuencia Molecular , Pan troglodytes/virología , Fragmentos de Péptidos/metabolismo , Fenotipo , Filogenia , Reacción en Cadena de la Polimerasa , Provirus/genética , Provirus/aislamiento & purificación , Receptores CCR5/genética , Receptores CCR5/metabolismo , Alineación de Secuencia , Homología de Secuencia de Aminoácido , TanzaníaRESUMEN
Four monoclonal antibodies (MAbs) recognizing HIV-1 reverse transcriptase (RT) were shown here to cross-react with the beta' subunit of Escherichia coli RNA polymerase (RNAP). The anti-RT MAbs bind to a peptide comprising residues 294-305 of the RT amino acid sequence. Computer analyses revealed sequence similarity between this peptide and two regions of the RNAP beta' subunit. MAb-binding studies using RT mutants suggested that the epitope is located to amino acids 652-663 of the beta' sequence. One of the MAbs which inhibited the polymerase activity of RT also mediated a dose dependent inhibition of the RNAP activity.
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Reacciones Cruzadas/inmunología , ARN Polimerasas Dirigidas por ADN/inmunología , ARN Polimerasas Dirigidas por ADN/metabolismo , Escherichia coli/enzimología , Transcriptasa Inversa del VIH/inmunología , Transcriptasa Inversa del VIH/metabolismo , VIH-1/enzimología , Secuencia de Aminoácidos , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/farmacología , Sitios de Unión , Western Blotting , Catálisis/efectos de los fármacos , ARN Polimerasas Dirigidas por ADN/antagonistas & inhibidores , ARN Polimerasas Dirigidas por ADN/química , Relación Dosis-Respuesta a Droga , Epítopos/química , Epítopos/genética , Epítopos/inmunología , Transcriptasa Inversa del VIH/química , Transcriptasa Inversa del VIH/genética , Cinética , Datos de Secuencia Molecular , Mutación/genética , Fragmentos de Péptidos/química , Fragmentos de Péptidos/genética , Fragmentos de Péptidos/inmunología , Conformación Proteica , Subunidades de Proteína , Relación Estructura-ActividadRESUMEN
Fimbrial adhesins that mediate attachment to host cells are produced by most virulent Escherichia coli isolates. These virulence factors play an important role in the initial stages of bacterial colonization and also in determination of the host and tissue specificity. Isolates belonging to serotype O78 are known to cause a large variety of clinical syndromes in farm animals and humans and have been shown to produce several types of adherence fimbriae. We studied the fimbrial adhesin from an avian septicemic E. coli isolate of serotype O78. Analysis of the genetic organization of the fac (fimbria of avian E. coli) gene cluster indicates that it belongs to the S-fimbrial adhesin family. Seven open reading frames coding for major and minor structural subunits were identified, and most of them showed a high degree of homology to the corresponding Sfa and Foc determinants. The least-conserved open reading frame was facS, encoding a protein known to play an important role in determining adherence specificity in other S-fimbrial gene clusters.
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Adhesinas de Escherichia coli/genética , Infecciones por Escherichia coli/veterinaria , Escherichia coli/genética , Genes Bacterianos , Enfermedades de las Aves de Corral/microbiología , Adhesinas de Escherichia coli/química , Secuencia de Aminoácidos , Animales , Pollos , Clonación Molecular , Escherichia coli/química , Escherichia coli/metabolismo , Infecciones por Escherichia coli/microbiología , Fimbrias Bacterianas/genética , Datos de Secuencia Molecular , Familia de Multigenes , Mapeo Restrictivo , Sepsis/microbiología , Sepsis/veterinaria , Análisis de Secuencia de ADNRESUMEN
Research involving clinical samples has demonstrated the utility of a 28-item personality disorder (PD) screening measure (Inventory of Interpersonal Problems--Personality Disorder scale [IIP-PD]) culled from the IIP in the prediction of the presence or absence of a PD (Pilkonis, Kim, Proietti, & Barkham, 1996). This article extends these diagnostic efficiency findings to nonclinical samples and presents additional data regarding the factor structure of the 28 IIP-PD items. Diagnostic efficiency statistics for the IIP-PD scale, calculated using both interview and self-report methods, support the utility of the IIP-PD scale as a screening tool for the presence or absence of a PD. High specificity estimates indicate that individuals who do not exceed Diagnostic and Statistical Manual of Mental Disorders (4th ed.; American Psychiatric Association, 1994) symptom thresholds rarely exceed the IIP-PD cutoff. Furthermore, a high negative predictive power (NPP) estimate derived using an interview-based diagnostic standard suggests that the IIP-PD scale accurately screens out individuals who do not have a PD. Finally, cross-validated confirmatory factor-analytic results involving items composing the 5 IIP PD subscales identified in previous research (Kim, Pilkonis, & Barkham, 1997) suggest that a measurement model with a single second-order factor (general PD) and 5 first-order factors (one representing each PD subscale) provided the best fit to the observed data compared to 2 other competing models.
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Relaciones Interpersonales , Trastornos de la Personalidad/diagnóstico , Inventario de Personalidad/estadística & datos numéricos , Adulto , Femenino , Humanos , Control Interno-Externo , Masculino , Persona de Mediana Edad , Trastornos de la Personalidad/psicología , Psicometría , Reproducibilidad de los ResultadosRESUMEN
BACKGROUND & AIMS: Ras genes are the most frequently detected oncogenes in human malignancies. Data regarding the frequency of c-K-ras mutations in esophageal, gastric, and small bowel tumors are limited and controversial. METHODS: DNA was extracted from 262 formalin-fixed, paraffin-embedded sections of gastrointestinal samples and tumors, including Barrett's esophagus, esophageal squamous cell carcinomas and adenocarcinomas, and small and large bowel adenomas and adenocarcinomas. The presence of c-K-ras codon 12 mutations was determined using a nonradioactive polymerase chain reaction-based restriction fragment length polymorphism assay. RESULTS: c-K-ras mutations were detected in 1 of 39 (2%) patients with Barrett's esophagus, 1 of 21 (5%) adenocarcinomas, 0 of 27 squamous cell carcinomas of the esophagus, and 1 of 32 (3%) gastric adenocarcinomas. It was also present in 8 of 20 (40%) and 10 of 28 (36%) small bowel adenomas and adenocarcinomas, respectively. Similar numbers were observed in 10 of 25 (40%) large bowel adenomas and 11 of 30 adenocarcinomas (37%). Mutations were not associated with age, gender, histology, grade, stage, location, or mortality. CONCLUSIONS: The frequency of codon 12 c-K-ras mutations in small and large bowel tumors is approximately 10-fold higher than that of tumors in the upper gastrointestinal tract.
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Adenocarcinoma/genética , Adenoma/genética , Neoplasias Gastrointestinales/genética , Genes ras/genética , Alelos , Esófago de Barrett/genética , Carcinoma de Células Escamosas/genética , Análisis Mutacional de ADN , Neoplasias Esofágicas/genética , Humanos , Neoplasias Intestinales/genética , Israel , Ciudad de Nueva York , Mutación Puntual , Reacción en Cadena de la Polimerasa , Polimorfismo Genético , Neoplasias Gástricas/genéticaRESUMEN
BACKGROUND AND PURPOSE: lipoprotein (a) (lp (a)) is a lipid-containing particle similar to LDL which has been found in atherosclerotic plaque. The role of lp (a) in ischemic stroke remains controversial, but some studies suggest lp (a) is particularly important as a risk factor for stroke in young adults. We investigated the role of lp (a) as a risk factor for stroke in young women enrolled in the Stroke Prevention in Young Women Study. METHODS: subjects were participants in a population-based, case-control study of risk factors for ischemic stroke in young women. Cases were derived from surveillance of 59 regional hospitals in the central Maryland, Washington DC, Pennsylvania and Delaware area. Lp (a) was measured in 110 cases and 216 age-matched controls. Demographics, risk factors, and stroke subtype were determined by interview and review of medical records. RESULTS: lp (a) values were higher in blacks than whites, but within racial groups, the distribution of lp (a) values was similar between cases and controls. After adjustment for age, race, hypertension, diabetes, cigarette smoking, coronary artery disease, total cholesterol and HDL cholesterol, the odds ratio for an association of lp (a) and stroke was 1.36 (95% CI 0.80-2.29). There was no dose-response relationship between lp (a) quintile and stroke risk. Among stroke subtypes, only lacunar stroke patients had significantly elevated lp (a) values compared to controls. CONCLUSIONS: we found no association of lp (a) with stroke in a population of young women with ischemic stroke. Small numbers of patients limit conclusions regarding risk in ischemic stroke subtypes, but we could not confirm previous suggestions of an association of lp (a) with atherosclerotic stroke in young adults.
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Infarto Cerebral/etiología , Lipoproteína(a)/sangre , Adolescente , Adulto , Arteriosclerosis/sangre , Arteriosclerosis/complicaciones , Arteriosclerosis/epidemiología , Biomarcadores/sangre , Estudios de Casos y Controles , Infarto Cerebral/sangre , Infarto Cerebral/epidemiología , Enfermedad Coronaria/sangre , Enfermedad Coronaria/complicaciones , Enfermedad Coronaria/epidemiología , Complicaciones de la Diabetes , Diabetes Mellitus/sangre , Diabetes Mellitus/epidemiología , Femenino , Humanos , Hipercolesterolemia/sangre , Hipercolesterolemia/complicaciones , Hipercolesterolemia/epidemiología , Hipertensión/sangre , Hipertensión/complicaciones , Hipertensión/epidemiología , Oportunidad Relativa , Prevalencia , Pronóstico , Grupos Raciales , Factores de Riesgo , Fumar/efectos adversos , Encuestas y Cuestionarios , Estados Unidos/epidemiologíaRESUMEN
BACKGROUND AND PURPOSE: Genetic enzyme variation and vitamin intake are important determinants of blood homocyst(e)ine levels. The prevalence of common genetic polymorphisms influencing homocyst(e)ine levels varies by race, and vitamin intake varies by socioeconomic status. Therefore, we examined the effect of vitamin intake, race, and socioeconomic status on the association of homocyst(e)ine with stroke risk. METHODS: All 59 hospitals in the greater Baltimore-Washington area participated in a population-based case-control study of stroke in young women. One hundred sixty-seven cases of first ischemic stroke among women aged 15 to 44 years were compared with 328 controls identified by random-digit dialing from the same region. Risk factor data were collected by standardized interview and nonfasting phlebotomy. Plasma homocyst(e)ine was measured by high-performance liquid chromatography and electrochemical detection. RESULTS: Blacks and whites did not differ in median homocyst(e)ine levels, nor did race modify the association between homocyst(e)ine and stroke. After adjustment for cigarettes per day, poverty status, and regular vitamin use, a plasma homocyst(e)ine level of >/=7.3 micromol/L was associated with an odds ratio for stroke of 1.6 (95% CI, 1.1 to 2.5). CONCLUSIONS: The association between elevated homocyst(e)ine and stroke was independent not only of traditional vascular risk factors but also of vitamin use and poverty status. The degree of homocyst(e)ine elevation associated with an increased stroke risk in young women is lower than that previously reported for middle-aged men and the elderly and was highly prevalent, being present in one third of the control group.