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1.
Artigo em Inglês | MEDLINE | ID: mdl-34486923

RESUMO

Over 200 million people in over 35 countries are affected by excessive fluoride in their waters. For people that do not have access to a centralized water treatment plant, there is a need for an on-site defluoridation system that requires no special operational expertise, does not use hazardous chemicals, and is sustainable by the local population. 8 different calcium phosphate precipitation systems were analyzed and tested for fluoride removal effectiveness. An effective system would have final fluoride concentrations less than 1.5 mg/L and final solutions with pH within drinkable limits. Phosphoric acid with the addition of a calcium carbonate source was found to have a 99.8% fluoride removal rate. Monosodium phosphate with addition of slaked lime was also found to be effective with a 99.98% fluoride removal rate. An optimal slaked lime to monosodium phosphate ratio that achieved effective fluoride removal and neutral pH was found. With 0.45 g of Ca(OH)2 and 1 g of NaH2PO4, initial fluoride concentrations up to 100 mg/L or more could be reduced to near zero concentrations, and a volume of approximately 337 mL of water with a concentration of 5 mg/L F- could to be reduced to less than 1.5 mg/L F-.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Carbonato de Cálcio , Fosfatos de Cálcio , Fluoretos , Humanos , Fosfatos , Poluentes Químicos da Água/análise
2.
AIDS Behav ; 24(12): 3562-3573, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32488554

RESUMO

Adherence to antiretroviral therapy (ART) is critical to achieving viral suppression. However, social determinants of health (SDoH) can undermine patient adherence to ART, resulting in drug resistance that compromises future treatment options. We assessed ART adherence and HIV-1 drug resistance at the national and state levels in the US and investigated their associations with SDoH and other HIV-related outcomes. Data were obtained from Symphony Health's Integrated Dataverse (IDV), Monogram/LabCorp Database, as well as national and publicly available databases, including Centers for Disease Control and Prevention (CDC), American Community Survey (ACS), and J. Kaiser Family Foundation (KFF). Inferential analyses were performed to investigate associations using patient-level data, and the results were reported by state and overall within the nation. Correlations between continuous variables were estimated by the Spearman's test, and that between continuous variable and categorical variable were estimated using one-way analysis of variance (ANOVA). State-level rates of poor adherence and resistance ranged from 26 to 55% and 20 to 54%, respectively. Female gender, non-white race, low education, poverty, and unemployment were associated with poor adherence; female gender was associated with drug resistance. Both adherence and resistance were correlated to HIV prevalence rates. Our findings suggest that US patients living with HIV face great challenges associated with poor ART adherence and HIV-1 drug resistance.


Assuntos
Infecções por HIV , HIV-1 , Fármacos Anti-HIV/uso terapêutico , Farmacorresistência Viral , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Humanos , Adesão à Medicação , Determinantes Sociais da Saúde
3.
Anal Chem ; 81(1): 509-14, 2009 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-19035650

RESUMO

In the assembly of microarrays and microarray-based chemical assays and enzymatic bioassays, most approaches use pins for contact spotting. Acoustic dispensing is a technology capable of nanoliter transfers by using acoustic energy to eject liquid sample from an open source well. Although typically used for well plate transfers, when applied to microarraying, it avoids the drawbacks of undesired physical contact with the sample; difficulty in assembling multicomponent reactions on a chip by readdressing, a rigid mode of printing that lacks patterning capabilities; and time-consuming wash steps. We demonstrated the utility of acoustic dispensing by delivering human cathepsin L in a drop-on-drop fashion into individual 50-nanoliter, prespotted reaction volumes to activate enzyme reactions at targeted positions on a microarray. We generated variable-sized spots ranging from 200 to 750 microm (and higher) and handled the transfer of fluorescent bead suspensions with increasing source well concentrations of 0.1 to 10 x 10(8) beads/mL in a linear fashion. There are no tips that can clog, and liquid dispensing CVs are generally below 5%. This platform expands the toolbox for generating analytical arrays and meets needs associated with spatially addressed assembly of multicomponent microarrays on the nanoliter scale.


Assuntos
Análise em Microsséries/métodos , Nanotecnologia/métodos , Acústica/instrumentação , Catepsina L , Catepsinas/química , Cisteína Endopeptidases/química , Corantes Fluorescentes/química , Glicerol/química , Humanos , Análise em Microsséries/instrumentação , Nanopartículas/química , Nanotecnologia/instrumentação
4.
Occup Environ Med ; 66(3): 161-8, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18805889

RESUMO

INTRODUCTION: To investigate possible associations between miscarriage and occupational exposures in the Shanghai textile industry. METHODS: A retrospective cohort study of miscarriages among 1752 women in the Shanghai textile industry was conducted. Reproductive history was self-reported by women and occupational work histories were collected from factory personnel records. Occupational exposures were assigned by linking work history information to an industry-specific job-exposure matrix informed by factory-specific textile process information and industrial hygiene assessments. Estimates of cotton dust and endotoxin exposure were also assigned. Odds ratios (OR) and 95% CI were estimated by multivariate logistic regression, with adjustment for age at pregnancy, educational level, smoking status of the woman and her spouse, use of alcohol, and woman's year of birth. RESULTS: An elevation in risk of a spontaneously aborted first pregnancy was associated with exposure to synthetic fibres (OR 1.89, 95% CI 1.20 to 3.00) and mixed synthetic and natural fibres (OR 3.31, 95% CI 1.30 to 8.42). No increased risks were observed for women working with solvents, nor were significant associations observed with quantitative cotton dust or endotoxin exposures. Associations were robust and similar when all pregnancies in a woman's reproductive history were considered. CONCLUSIONS: Occupational exposure to synthetic fibres may cause miscarriages, and this possibility should be the subject of further investigation.


Assuntos
Aborto Espontâneo/etiologia , Poluentes Ocupacionais do Ar/toxicidade , Poeira , Doenças Profissionais/etiologia , Indústria Têxtil , Aborto Espontâneo/induzido quimicamente , Adulto , Idoso , China , Estudos de Coortes , Fibra de Algodão , Endotoxinas/toxicidade , Feminino , Humanos , Pessoa de Meia-Idade , Doenças Profissionais/induzido quimicamente , Exposição Ocupacional , Razão de Chances , Gravidez , Medição de Risco/métodos
5.
Anal Biochem ; 381(1): 101-6, 2008 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-18616925

RESUMO

Miniaturizing bioassays to the nanoliter scale for high-throughput screening reduces the consumption of reagents that are expensive or difficult to handle. Through the use of acoustic dispensing technology, nanodroplets containing 10 microM ATP (3 microCi/microL (32)P) and reaction buffer in 10% glycerol were positionally dispensed to the surface of glass slides to form 40-nL compartments (100 droplets/slide) for Pim1 (proviral integration site 1) kinase reactions. The reactions were activated by dispensing 4 nL of various levels of a pyridocarbazolo-cyclopentadienyl ruthenium complex Pim1 inhibitor, followed by dispensing 4 nL of a Pim1 kinase and peptide substrate solution to achieve final concentrations of 150 nM enzyme and 10 microM substrate. The microarray was incubated at 30 degrees C (97% R(h)) for 1.5 h. The spots were then blotted to phosphocellulose membranes to capture phosphorylated substrate. With phosphor imaging to quantify the washed membranes, the assay showed that, for doses of inhibitor from 0.75 to 3 microM, Pim1 was increasingly inhibited. Signal-to-background ratios were as high as 165, and average coefficients of variation for the assay were approximately 20%. Coefficients of variation for dispensing typical working buffers were under 5%. Thus, microarrays assembled by acoustic dispensing are promising as cost-effective tools that can be used in protein assay development.


Assuntos
Acústica , Nanotecnologia/métodos , Análise Serial de Proteínas/métodos , Corantes Fluorescentes/metabolismo , Proteínas Fúngicas , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Reprodutibilidade dos Testes , Soluções
6.
Neuroscience ; 137(1): 83-92, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16289354

RESUMO

Neurons are added throughout life to the dentate gyrus of the hippocampus of the mammalian brain. Progenitors residing in the dentate gyrus progress through three distinct stages of adult neurogenesis: proliferation, survival and differentiation. One of the most potent factors which regulates adult neurogenesis is adrenal-derived glucocorticoids. Raised levels of glucocorticoids suppress progenitor division, while removal of glucocorticoids by adrenalectomy stimulates proliferation of these cells in the dentate gyrus. We have recently reported that both pre- and post-mitotic corticoid environments powerfully regulate survival of progenitor cells in a time-dependent manner. However, it is unknown if glucocorticoids alter the process of neuronal differentiation, since not all of the newly-formed cells acquire a neuronal fate during development. Here we employ triple immuno-fluorescence staining techniques to phenotype surviving progenitor cells 28 days after labeling. Results show that high levels of corticosterone (the major glucocorticoid in rodents) either before or after progenitor labeling discouraged the acquisition of neuronal fate. Similar to its effect on survival, post-mitotic corticosterone also regulates neuronal differentiation in a time-dependent fashion, but this action is most prominent from around 19-27 days after the cells were born. In contrast, a corticoid-free environment either before or after progenitor proliferation did not affect neuronal differentiation. Combining these data with previous survival data obtained from the same animals allowed us to estimate the total number of neurons formed resulting from different corticoid treatments. Raised corticosterone significantly reduced neuronal production while adrenalectomy resulted in significantly higher number of neurons in the adult male rat hippocampus.


Assuntos
Diferenciação Celular/fisiologia , Corticosterona/metabolismo , Hipocampo/citologia , Neurônios/citologia , Células-Tronco/citologia , Animais , Imunofluorescência , Hipocampo/metabolismo , Masculino , Neurônios/metabolismo , Ratos , Células-Tronco/metabolismo
7.
Diabetes Care ; 21(5): 711-6, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9589229

RESUMO

OBJECTIVE: To investigate the effect of varying the volume of sugar meals on the post-prandial glycemic response (PGR). RESEARCH DESIGN AND METHODS: On six separate occasions, after an overnight fast, blood glucose concentrations were measured in eight healthy subjects (34 +/- 4 years of age, BMI 22.9 +/- 0.9 kg/m2) after the consumption of 25 g glucose, sucrose, or fructose dissolved in either 200 or 600 ml of water. Blood was obtained at fasting and then at times 15, 30, 45, 60, and 90 min after the start of the test meal. RESULTS: PGR was found to be influenced by carbohydrate type (P < 0.001). Mean response areas (min.mmol.l-1) to the three sugars were statistically different (P < 0.05). Glucose had the highest response area (90.0 +/- 8.1), followed by sucrose (61.3 +/- 5.0) and then fructose (14.7 +/- 2.8). Independent of this effect, PGR was also found to be influenced by volume dose (P < 0.01). By tripling meal volume from 200 to 600 ml, PGR areas were significantly increased for all three sugars, glucose (79.3 +/- 10.3 vs. 100.8 +/- 12.0, P = 0.035), sucrose (52.6 +/- 5.5 vs. 70 +/- 7.4, P = 0.0094), and fructose (11.0 +/- 3.8 vs. 18.4 +/- 3.9, P = 0.012). Where the effects of time (P < 0.05) and dose (P < 0.05) were determined to be independent (interaction nonsignificant) for all three sugars, this increase in volume also significantly increased glycemic concentrations at 15 min, for glucose (P = 0.033) and sucrose (P = 0.026), suggesting that changes in gastric emptying time may be a mechanism of action. CONCLUSIONS: Varying the volume of liquid sugar meals alters PGR. Understanding this concept may help to reduce variability both in the glycemic testing of foods and oral glucose tolerance testing.


Assuntos
Glicemia/efeitos dos fármacos , Sacarose Alimentar/farmacologia , Frutose/farmacologia , Glucose/farmacologia , Administração Oral , Adulto , Análise de Variância , Glicemia/metabolismo , Sacarose Alimentar/administração & dosagem , Relação Dose-Resposta a Droga , Feminino , Frutose/administração & dosagem , Glucose/administração & dosagem , Humanos , Masculino , Cooperação do Paciente , Período Pós-Prandial , Fatores de Tempo
8.
Gene ; 68(2): 193-203, 1988 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-3065142

RESUMO

The synthesis, processing and secretion of insulin-like growth factor-1 (IGF-1 or somatomedin-C) fused to LamB and OmpF secretion leader sequences in Escherichia coli have been investigated. Expression and secretion of IGF-1 was achieved. The major portion of this secreted IGF-1 accumulated in the periplasmic space as insoluble aggregates. A small amount of IGF-1 was found folded in its native conformation in the medium. The lamB and ompF signal sequences were fused to the 5' coding sequence of IGF-1. Fusion of the lamB signal sequence directly to IGF-1 (lamB-IGF-1) resulted in accumulation of 16-20 micrograms/A550/ml of correctly processed IGF-1 in the periplasmic space. The processing efficiency of LamB-IGF-1 and OmpF-IGF-1 was enhanced in an E. coli strain bearing a prlA4 mutation. Amino acid sequence analysis of IGF-1 secreted into the periplasm and exported into the medium confirmed the precise removal of the LamB or OmpF signal sequence. IGF-1 synthesized in E. coli was demonstrated to be active in a cell proliferation bioassay.


Assuntos
Escherichia coli/genética , Genes Sintéticos , Genes , Fator de Crescimento Insulin-Like I/genética , Somatomedinas/genética , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/ultraestrutura , Vetores Genéticos , Fator de Crescimento Insulin-Like I/biossíntese , Dados de Sequência Molecular , Proteínas Recombinantes de Fusão/biossíntese , Mapeamento por Restrição
9.
Neuroscience ; 123(4): 951-65, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-14751288

RESUMO

Axon guidance molecules and related proteins such as semaphorin 3A, neuropilin-1, plexin-1, netrin-1, growth-associated protein, olfactory marker protein, cypin and collapsin response mediator proteins guide the development of neural circuits in the olfactory bulb. In this study, transcriptions of these genes were examined in the olfactory bulb of female, male and neonatal testosterone propionate-treated female rats at the ages of 2, 5, 10, 15, 20, 25, 30 and 45 days. The semaphorin 3A, neuropilin-1, growth-associated protein and collapsin response mediator protein 1-5 genes were expressed significantly higher during the early development stages than in adulthood while the opposite is true for the olfactory marker protein. The expression profile of cypin and netrin-1 was relatively constant through development. A late effect of the neonatal testosterone propionate treatment on netrin-1, growth-associated protein, olfactory marker protein, collapsin response mediator proteins 1, 3, 4 and cypin gene expression was observed. The expression profiles of collapsin response mediator proteins and their related genes in the developing olfactory bulb confirmed most studies on the relationship between collapsin response mediator proteins and development in the brain. Sex differences of semaphorin 3A, neuropilin-1 as well as collapsin response mediator protein 3 at the early development stage and the late effect of neonatal testosterone propionate treatment on the expressions of netrin-1, growth-associated marker protein, cypin and collapsin response mediator proteins 1, 3 and 5 genes may indicate a possible role of these molecules on sexual differentiation of the olfactory bulb.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Axônios/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Bulbo Olfatório/crescimento & desenvolvimento , Bulbo Olfatório/metabolismo , Diferenciação Sexual/fisiologia , Envelhecimento , Análise de Variância , Animais , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/metabolismo , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Feminino , Proteína GAP-43/genética , Proteína GAP-43/metabolismo , Guanina Desaminase/genética , Guanina Desaminase/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular , Masculino , Fatores de Crescimento Neural/genética , Fatores de Crescimento Neural/metabolismo , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Netrina-1 , Neuropilina-1/genética , Neuropilina-1/metabolismo , Proteína de Marcador Olfatório , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Gravidez , RNA Mensageiro/biossíntese , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Semaforinas/genética , Semaforinas/metabolismo , Proteínas Supressoras de Tumor
10.
Brain Res Dev Brain Res ; 119(2): 187-94, 2000 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-10675768

RESUMO

In this study, expressions of cell-cycle-related genes: p53, retinoblastoma (Rb), p21, bcl-2(alpha), bcl-2(beta); protooncogene c-ski; glial cell marker protein gene S100beta; neurotransmitter gene, substance P and sexual-differentiation-related genes, androgen receptor (AR) and estrogen receptor beta (ER(beta)), are studied in the olfactory bulb of groups of both six female and six male rats at the ages of 3, 10, 20 and 40 days. Expressions of housekeeping genes such as beta-actin, cyclophilin and proliferating cell nuclear antigens (PCNA) are determined using reverse transcription polymerase chain reaction (RT-PCR) for the correction of unequal amount of cDNA added into the samples. Using labeled 32P-dCTP and Phosphorimager technology, relative abundance of radioactivities of the PCR products is obtained by dividing the radioactivity of each individual sample by the corresponding radioactivities of different housekeeping genes. Data evaluated by Two-way ANOVA indicate that only the bcl-2(alpha) gene expression is affected significantly by age, sex and their interactions no matter which of the three housekeeping genes is used for correction. When beta-actin was used for corrections, effects of age but not sex were found in the expressions of p53, Rb, p21, AR, ER(beta), substance P and S100beta genes, but not in bcl-2(beta), c-ski, cyclophilin and PCNA genes. While cyclophilin was used for corrections, only the p53, Rb, AR, ER(beta), substance P and S100beta but not the bcl-2(beta), p21, c-ski, PCNA and beta-actin genes are affected by age. They are all not influenced by sex of the animals. Only the AR, ER(beta) and S100beta genes are age-dependent when PCNA was used for the correction. The other gene expressions are not altered by sex, while the interactions of age and sex were found to be significantly affecting the bcl-2(beta) gene expression. Conclusively, developmental changes of the p53, Rb, AR, ER(beta), substance P and S100beta genes expressions are quite evidenced while only the bcl-2(alpha) gene seems to change significantly during the sexual differentiation of olfactory bulb in rats.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Bulbo Olfatório/crescimento & desenvolvimento , Bulbo Olfatório/fisiologia , Proteínas S100 , Diferenciação Sexual , Actinas/genética , Fatores Etários , Animais , Proteínas de Ligação ao Cálcio/genética , Primers do DNA , Proteínas de Ligação a DNA/genética , Feminino , Masculino , Fatores de Crescimento Neural/genética , Bulbo Olfatório/química , Peptidilprolil Isomerase/genética , Antígeno Nuclear de Célula em Proliferação/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Ratos , Ratos Sprague-Dawley , Receptores Androgênicos/genética , Receptores de Estrogênio/genética , Proteína do Retinoblastoma/genética , Subunidade beta da Proteína Ligante de Cálcio S100 , Substância P/genética , Proteína Supressora de Tumor p53/genética
11.
Am J Ophthalmol ; 124(6): 797-804, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9402826

RESUMO

PURPOSE: To evaluate the effectiveness and safety of diode laser contact transscleral cyclophotocoagulation in Asian patients with refractory glaucoma by lower energy settings with an innovative probe featuring a glass ball tip that focused the laser beam onto the ciliary body. METHODS: This prospective clinical study included consecutive Asian patients with dark irides and confirmed for glaucoma. Only one eye of each patient was treated. Diode laser contact transscleral cyclophotocoagulation treatment was performed with the center of the probe placed 1.5 mm behind the limbus. About 30 pulses of 810-mm laser radiation (power, 1.8 to 2.0 W; duration, 0.3 to 0.5 second) were applied around the eye. Patients were examined at fixed postoperative intervals. Intraocular pressure levels and postoperative complications were recorded. The relation between patient and disease characteristics, total laser energy delivered, and intraocular pressure effects were analyzed. RESULTS: Thirty-three patients were studied, with a mean follow-up period of 9.4 months. An average 56% of patients showed a 30% or greater drop in intraocular pressure. About 38% of patients achieved sustained intraocular pressure lowering to below 22 mm Hg at 18 months. Complications were few and included transient hypotony and iritis. CONCLUSIONS: In Asian patients with refractory glaucoma or painful glaucomatous eyes with poor visual acuity (defined for this study as worse than 20/200), low-energy-setting diode laser contact transscleral cyclophotocoagulation by means of the glass ball probe is relatively effective and safe.


Assuntos
Corpo Ciliar/cirurgia , Etnicidade , Glaucoma/cirurgia , Fotocoagulação a Laser , Adulto , Idoso , China , Feminino , Glaucoma/etnologia , Glaucoma/fisiopatologia , Humanos , Índia , Pressão Intraocular/fisiologia , Fotocoagulação a Laser/efeitos adversos , Fotocoagulação a Laser/métodos , Malásia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Prospectivos , Reoperação , Segurança , Esclera , Resultado do Tratamento , Acuidade Visual/fisiologia
12.
Photochem Photobiol ; 68(5): 685-91, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9867601

RESUMO

The nonsteroidal anti-inflammatory drugs (NSAID), naproxen, sulindac and indomethacin, were shown to donate electrons to nitro blue tetrazolium (NBT) when irradiated with UV light in deoxygenated aqueous buffer solution (pH 7.4, 30 degrees C). The reaction was monitored spectrophotometrically by the appearance of the diformazan reduction product from NBT. The electron transfer process facilitates the decomposition of the drugs. Naproxen in the presence of NBT is photodegraded principally to the alcohol (2-[1-hydroxyethyl]-6-methoxynaphthalene) at a rate approximately 20-fold faster than when irradiated alone in deoxygenated conditions. The photoproduct from naproxen also participates in the electron transfer to NBT but at a much slower rate than naproxen. Irradiation of sulindac or indomethacin in the presence of NBT caused the slow photoreduction of NBT to diformazan. In the absence of NBT, indomethacin and sulindac are essentially unreactive when irradiated in aqueous solution. The ability of a number of NSAID to act as electron donors in their ground state was studied by observing their oxidation by potassium peroxodisulfate in pH 7.0 phosphate buffer at 50 degrees C. The HPLC analysis of the drug remaining showed that the 2-arylpropionic acid NSAID (naproxen, ibuprofen, ketoprofen and suprofen) reacted at a rate equivalent to the thermal decomposition of peroxodisulfate. The major products were the same as detected in the photooxidation of these drugs, resulting from decarboxylation and oxygen addition but also included a dimeric compound. On the other hand, the NSAID that do not contain the propionic acid substituent all reacted more slowly with peroxodisulfate, enabling specific reaction rate constants to be evaluated.


Assuntos
Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/efeitos da radiação , Raios Ultravioleta , Diflunisal/química , Diflunisal/efeitos da radiação , Elétrons , Temperatura Alta , Indicadores e Reagentes , Indometacina/química , Indometacina/efeitos da radiação , Nitroazul de Tetrazólio , Sulindaco/química , Sulindaco/efeitos da radiação , Termodinâmica
13.
IEEE Trans Med Imaging ; 20(11): 1123-30, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11700738

RESUMO

BACKGROUND: Although there have been recent advances in echocardiography, many studies remain suboptimal due to poor image quality and unclear blood-myocardium border. We developed a novel image processing technique, cardiac variability imaging (CVI), based on the variance of pixel intensity values during passage of ultrasound microbubble contrast into the left ventricle chamber, with the aim of enhancing endocardial border delineation and image quality. METHODS AND RESULTS: CVI analysis was performed on simulated data to test and verify the mechanism of image enhancement. Then CVI analysis was applied to echocardiographic images obtained in two different clinical studies, and still images were interpreted by expert reviewers. In the first study (N = 15), using contrast agent EchoGen, the number of observable wall segments in end-diastolic images, for example, was significantly increased by CVI (4.93) as compared to precontrast (3.28) and contrast images (3.36), P < 0.001 for both comparisons to CVI. In the second study (N = 8), using contrast agent Optison, interobserver variability of manually traced end-diastolic volumes was significantly decreased using CVI (22.3 ml) as compared to precontrast (63.4) and contrast images (49.0), P < 0.01 for both comparisons to CVI. CONCLUSION: CVI can substantially enhance endocardial border delineation and improve echocardiographic image quality and image interpretation.


Assuntos
Ecocardiografia , Aumento da Imagem , Variações Dependentes do Observador , Algoritmos , Endocárdio/diagnóstico por imagem , Análise de Fourier , Ventrículos do Coração/diagnóstico por imagem , Humanos , Modelos Teóricos
14.
J Expo Anal Environ Epidemiol ; 10(6 Pt 1): 509-17, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11140435

RESUMO

Contaminated site cleanup decisions may require estimation of dermal exposures to soil. Telephone surveys represent one means of obtaining relevant activity pattern data. The initial Soil Contact Survey (SCS-I), which primarily gathered information on the activities of adults, was conducted in 1996. Data describing adult behaviors have been previously reported. Results from a second Soil Contact Survey (SCS-II), performed in 1998-1999 and focused on children's activity patterns, are reported here. Telephone surveys were used to query a randomly selected sample of U.S. households. A randomly chosen child, under the age of 18 years, was targeted in each responding household having children. Play activities as well as bathing patterns were investigated to quantify total exposure time, defined as activity time plus delay until washing. Of 680 total survey respondents, 500 (73.5%) reported that their child played outdoors on bare dirt or mixed grass and dirt surfaces. Among these "players," the median reported play frequency was 7 days/week in warm weather and 3 days/week in cold weather. Median play duration was 3 h/day in warm weather and 1 h/day in cold weather. Hand washes were reported to occur a median of 4 times per day in both warm and cold weather months. Bath or shower median frequency was seven times per week in both warm and cold weather. Finally, based on clothing choice data gathered in SCS-I, a median of about 37% of total skin surface is estimated to be exposed during young children's warm weather outdoor play.


Assuntos
Proteção da Criança , Exposição Ambiental/análise , Inquéritos Epidemiológicos , Poluentes do Solo/efeitos adversos , Atividades Cotidianas , Adolescente , Adulto , Criança , Pré-Escolar , Clima , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Procurador , Tempo (Meteorologia)
15.
Ann Clin Lab Sci ; 28(4): 215-23, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9715348

RESUMO

Overexpression and/or amplification of HER-2/neu gene have been found to be prognostic and predictive in breast and other cancers. Fluorescence in situ hybridization (FISH) assay, with its sensitivity and specificity, can be a superior method of detection when its performance characteristics are demonstrated. A multicenter study was initiated to evaluate the reproducibility of the LSI HER-2/neu SpectrumOrange and CEP 17 SpectrumGreen Dual Color DNA Probe for enumeration of both the HER-2/neu gene and chromosome 17 (signals) in interphase cells. Section slides were prepared from four cell lines (H, E, R, and N) with known ratios of the HER-2/neu to CEP 17 copy numbers (approximately H = 1.10, E = 1.70, R = 4.50, N = 9.0). The study variable was the ratios of the HER-2/neu to chromosome 17 copy numbers. Reproducibility with respect to assay, site, lot, day and reader was evaluated at 3 centers. Out of 120 specimen slides, 100 percent were successfully assayed. There were no significant differences among: (1) four repeated assays of the same specimen (p = 0.99), (2) the four probe lots (p = 0.33), or (3) the four study days (p = 0.54). There was statistically significant, but not important differences among centers and between readers. The ratios of the HER-2/neu to chromosome 17 copy numbers were estimated with accuracy and precision; the mean ratios (and sd) for specimens, H, E, R, and N were 1.05 (0.06), 1.81 (0.12), 4.48 (0.28), and 8.60 (1.23), respectively. In summary, assays with the LSI HER-2/neu and CEP 17 Dual Color DNA Probe Kit, conducted at three sites by 6 different technicians, over 8 assay days, using kits from four lots, were performed with a high success rate in paraffin-embedded specimens. The signal enumeration was also accurate and precise. This study demonstrated that the results obtained by using the LSI HER-2/neu SpectrumOrange and CEP 17 SpectrumGreen Dual Color DNA Probe Kit are reliable and reproducible.


Assuntos
Neoplasias da Mama/diagnóstico , Sondas de DNA/química , DNA de Neoplasias/análise , Genes erbB-2/genética , Cromossomos Humanos Par 17/genética , Corantes/metabolismo , Dextranos/metabolismo , Amplificação de Genes/genética , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Hibridização In Situ/métodos , Microscopia de Fluorescência , Inclusão em Parafina , Projetos Piloto , Kit de Reagentes para Diagnóstico , Reprodutibilidade dos Testes , Células Tumorais Cultivadas
16.
Ann Clin Lab Sci ; 30(1): 41-8, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10678582

RESUMO

Amplification and/or overexpression of HER-2/neu has been shown to be both a prognostic and predictive marker in breast cancer. Recent studies have also confirmed the efficacy of Herceptin (trastuzumab) as adjuvant therapy for patients with overexpression of HER-2/neu. Therefore, it is critical that precise and reproducible assays be used in the clinical laboratory setting for determination of the HER-2/neu status in patients with breast cancer. The objective of this study was to determine the portability (reproducibility between different institutions) of the PathVysion HER-2 fluorescence in situ hybridization (FISH) assay used for detection of amplification of the HER-2/neu gene in formalin-fixed, paraffin-embedded tissue sections of invasive ductal carcinoma of the breast. Study specimens consisted of one breast tumor with a normal HER-2/neu copy number, two tumors with a low level, and one tumor with a high level of HER-2/neu amplification. The PathVysion HER-2 assay was shown to be highly reproducible on different assay days (n = 3) and between different institutions (n = 5) in the detection of amplification of the HER-2/neu gene in routinely processed clinical specimens of breast carcinoma. In addition, this study examined the feasibility of enumerating FISH signals in 20 nuclei in contrast to 60 nuclei per specimen. Although a modest increase in variation was observed when analyzing 20 compared to 60 nuclei, the mean ratios were similar. Therefore, analysis of as few as 20 nuclei with this FISH HER-2/neu assay may be sufficient for determining the amplification level of the HER-2/neu gene.


Assuntos
Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Hibridização in Situ Fluorescente/normas , Receptor ErbB-2/genética , Antimetabólitos Antineoplásicos/administração & dosagem , Antineoplásicos/administração & dosagem , Antineoplásicos Alquilantes/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Núcleo Celular/genética , Ciclofosfamida/administração & dosagem , DNA de Neoplasias/análise , Método Duplo-Cego , Doxorrubicina/administração & dosagem , Feminino , Fluoruracila/administração & dosagem , Amplificação de Genes , Regulação Neoplásica da Expressão Gênica , Humanos , Reprodutibilidade dos Testes
17.
Can Respir J ; 6(4): 332-5, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10463961

RESUMO

OBJECTIVE: To evaluate the yield and cost effectiveness of transbronchial needle aspiration (TBNA) in the assessment of mediastinal and/or hilar lymphadenopathy. DESIGN: Retrospective study. SETTING: A university hospital. POPULATION STUDIED: Ninety-six patients referred for bronchoscopy with computed tomographic evidence of significant mediastinal or hilar adenopathy. RESULTS: Ninety-nine patient records were reviewed. Three patients had two separate bronchoscopy procedures. TBNA was positive in 42 patients (44%) and negative in 54 patients. Of the 42 patients with a positive aspirate, 40 had malignant cytology and two had cells consistent with benign disease. The positive TBNA result altered management in 22 of 40 patients with malignant disease and one of two patients with benign disease, thereby avoiding further diagnostic procedures. The cost of these subsequent procedures was estimated at $27,335. No complications related to TBNA were documented. CONCLUSIONS: TBNA is a high-yield, safe and cost effective procedure for the diagnosis and staging of bronchogenic cancer.


Assuntos
Carcinoma Broncogênico/patologia , Neoplasias Pulmonares/patologia , Adenocarcinoma/patologia , Biópsia por Agulha , Broncoscopia , Análise Custo-Benefício , Humanos , Estadiamento de Neoplasias , Estudos Retrospectivos
18.
Sci Total Environ ; 274(1-3): 79-91, 2001 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-11453307

RESUMO

Analyses of competing risks are currently limited by the lack of empirically well-founded and generalizable quantitative methods. Specifically, quantitative methods for comparative risk analysis require the consideration of the population impacted, the duration of impact, the health endpoints at risk, and the impact on individual quality of life. Whereas risk analysis can be used to provide quantitative estimates of disease incidence, environmental health policy analyses do not often account for differences in health impact from alternative disease states. We discuss the methodological issues related to the use of quality adjusted life years (QALY) as a metric for normalizing expected disease incidence to account for health impact. Through a case study of the risks and benefits of fish consumption, we demonstrate the use of QALY weights with dose-response models for environmental health policy decision making. We suggest that, although this approach can be generalized for use in comparative risk and health policy analysis, it is informationally intensive and requires additional assumptions to those used in traditional safety/risk assessment.


Assuntos
Saúde Ambiental , Política de Saúde , Modelos Biológicos , Anos de Vida Ajustados por Qualidade de Vida , Adulto , Distribuição por Idade , Animais , Criança , Proteínas Alimentares , Feminino , Peixes , Humanos , Tábuas de Vida , Masculino , Modelos Estatísticos , Mortalidade , Medição de Risco , Fatores de Risco
19.
ANZ J Surg ; 71(12): 740-3, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11906390

RESUMO

BACKGROUND: To examine the common presentations and management of acute epiglottitis in adults. METHOD: Retrospective clinical study of 17 consecutive adult patients who presented to the Royal Melbourne Hospital between January 1988 and December 2000 was undertaken. RESULTS: The mean patient age was 47 years (range 20-87 years) and the male-to-female ratio was 1.8 : 1.0. Peak incidence occurred in September during early spring. All patients presented with sore throat and dysphagia; however, respiratory distress was only noted in 65%. The most common signs were temperature and tachycardia. Four patients (23%) required endotracheal intubation, which was performed electively in three and as an emergency in one. Three of 14 blood cultures were positive, two yielded Haemophilus influenzae type b and one yielded Streptococcus mitis. One of the four throat cultures was positive for Haemophilus influenzae type b. Twelve patients underwent awake flexible laryngoscopy under topical anaesthetic as part of their initial assessment, and there were no complications associated with this procedure. There was no mortality. CONCLUSIONS: The diagnosis of acute epiglottitis in the adult population is difficult as respiratory distress may be absent. Patients who have a significant sore throat with no obvious aetiology should have direct visualization of their larynx by flexible laryngoscopy. Lateral X-ray of neck is of limited value. Once diagnosed, these patients should be hospitalized and monitored as airway obstruction may develop rapidly.


Assuntos
Epiglotite/diagnóstico , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Cefalosporinas/uso terapêutico , Cloranfenicol/uso terapêutico , Transtornos de Deglutição/etiologia , Epiglotite/complicações , Epiglotite/tratamento farmacológico , Epiglotite/microbiologia , Feminino , Haemophilus influenzae tipo b/isolamento & purificação , Humanos , Laringoscopia , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Streptococcus/isolamento & purificação , Vitória
20.
Diagn Cytopathol ; 23(6): 431-4, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11074654

RESUMO

To evaluate our experience with the cytodiagnosis of primary lung cancers by transthoracic fine-needle aspiration (TFNA), 106 bronchogenic carcinomas (BC) and 6 neuroendocrine tumors of the lung (NTL) with adequate needle aspirates were reviewed. The cytodiagnostic accuracy rates of BCs were 75.5%, 72%, 100%, 53%, and 50% for bronchogenic adenocarcinomas, squamous-cell carcinomas, small-cell carcinomas, large-cell carcinomas, and mixed carcinomas, respectively. Of the 6 NTLs, 4 typical carcinoid tumors (CT) were correctly diagnosed, 1 atypical CT was wrongly identified as small-cell carcinoma, and 1 large-cell NTL was mistaken for an adenocarcinoma.


Assuntos
Biópsia por Agulha/métodos , Carcinoma Broncogênico/diagnóstico , Neoplasias Pulmonares/diagnóstico , Tumores Neuroendócrinos/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias , Punções , Reprodutibilidade dos Testes , Tórax
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