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1.
Neuroimage ; 216: 116529, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31931155

RESUMO

In neuroscience, empathy is often conceived as relatively automatic. The voluntary control that people can exert on brain mechanisms that map the emotions of others onto our own emotions has received comparatively less attention. Here, we therefore measured brain activity while participants watched emotional Hollywood movies under two different instructions: to rate the main characters' emotions by empathizing with them, or to do so while keeping a detached perspective. We found that participants yielded highly consistent and similar ratings of emotions under both conditions. Using intersubject correlation-based analyses we found that, when encouraged to empathize, participants' brain activity in limbic (including cingulate and putamen) and somatomotor regions (including premotor, SI and SII) synchronized more during the movie than when encouraged to detach. Using intersubject functional connectivity we found that comparing the empathic and detached perspectives revealed widespread increases in functional connectivity between large scale networks. Our findings contribute to the increasing awareness that we have voluntary control over the neural mechanisms through which we process the emotions of others.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Empatia/fisiologia , Imageamento por Ressonância Magnética/métodos , Filmes Cinematográficos , Adulto , Humanos , Masculino , Estimulação Luminosa/métodos , Adulto Jovem
2.
J Oral Pathol Med ; 48(5): 389-399, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30825343

RESUMO

BACKGROUND: Oral squamous cell carcinoma (OSCC) is a deadly disease with a mere 40% five-year survival rate for patients with advanced disease. Previously, we discovered that capsazepine (CPZ), a transient receptor potential channel, Vanilloid subtype 1 (TRPV1) antagonist, has significant anti-tumor effects against OSCC via a unique mechanism-of-action that is independent of TRPV1. Thus, we developed novel CPZ analogs with more potent anti-proliferative effects (CIDD-24, CIDD-99, and CIDD-111). METHODS: Using OSCC xenograft models, we determined the efficacy of these analogs in vivo. TRPV1 interactions were evaluated using calcium imaging and a rat model of orofacial pain. Anti-cancer mechanism(s)-of-action were assessed by cell cycle analysis and mitochondrial depolarization assays. RESULTS: CIDD-99 was the most potent analog demonstrating significant anti-tumor effects in vivo (P < 0.001). CIDD-24 was equipotent to the parent compound CPZ, but less potent than CIDD-99. CIDD-111 was the least efficacious analog. Calcium imaging studies confirmed that CIDD-99 neither activates nor inhibits TRPV1 confirming that TRPV1 activity is not involved in its anti-cancer effects. All analogs induced an S-phase block, dose-dependent mitochondrial depolarization, and apoptosis. Histological analyses revealed increased apoptosis and reduced cell proliferation in tumors treated with these analogs. Importantly, CIDD-99 had the most dramatic anti-tumor effects with 85% of tumors resolving leaving only minute traces of viable tissue. Additionally, CIDD-99 was non-noxious and demonstrated no observable adverse reactions CONCLUSION: This study describes a novel, highly efficacious, CPZ analog, CIDD-99, with dramatic anti-tumor effects against OSCC that may be efficacious as a lone therapy or in combination with standard therapies.


Assuntos
Apoptose , Capsaicina/análogos & derivados , Carcinoma de Células Escamosas/tratamento farmacológico , Estresse do Retículo Endoplasmático , Isoquinolinas/farmacologia , Mitocôndrias/efeitos dos fármacos , Neoplasias Bucais/tratamento farmacológico , Canais de Cátion TRPV/antagonistas & inibidores , Animais , Capsaicina/farmacologia , Linhagem Celular Tumoral , Feminino , Humanos , Masculino , Camundongos , Camundongos Nus , Mitocôndrias/patologia , Ratos , Ratos Sprague-Dawley , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Pediatr Obes ; 13(6): 342-347, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-28730729

RESUMO

INTRODUCTION: Traffic-related air pollution causes fatty liver, inflammation and fibrosis in animal models, but there have been few studies in humans. OBJECTIVES: To test the hypothesis that traffic-related air pollution causes non-alcoholic fatty liver disease (NAFLD) and increased markers for non-alcoholic steatohepatitis (NASH); and that NAFLD increases liver susceptibility to increased NASH risk. METHODS: Data collected prospectively from 74 overweight or obese children were obtained from the Yale Pediatric Obesity Clinic. Traffic-related air pollution was characterized as vehicle traffic volume on major roads within a 1 km residential buffer, and as residential nitrogen dioxide (NO2 ) exposure. Outcomes were hepatic fat fraction (HFF) measured by magnetic resonance imaging, liver enzymes using standard assays and plasma cytokeratin-18 (CK-18) by immunosorbent assays. RESULTS: Significant non-linear relationships with air pollution and CK-18 were found. Plasma CK-18 at follow-up increased from approximately 150 U/L to almost 200 U/L as residential traffic volume increased from 220 000 vehicle-km to 330 000 vehicle-km, after adjustment for baseline CK-18, age and gender. Among patients with NAFLD at baseline, CK-18 increased from 140 U/L to 200 U/L (a 1.5 standard deviation increase in CK-18) as NO2 increased from 8 to 10 ppb. CONCLUSIONS: Traffic-related air pollution was associated with CK-18. Effects were larger in children with pre-existing NAFLD at study entry.


Assuntos
Poluição do Ar/efeitos adversos , Queratina-18/sangue , Hepatopatia Gordurosa não Alcoólica/sangue , Obesidade Infantil/complicações , Poluição Relacionada com o Tráfego/efeitos adversos , Poluentes Atmosféricos/análise , Apoptose/fisiologia , Biomarcadores/sangue , Criança , Feminino , Seguimentos , Humanos , Fígado/patologia , Imageamento por Ressonância Magnética , Masculino , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/etiologia , Estudos Prospectivos , Fatores de Risco , Transaminases/sangue , Emissões de Veículos/análise
5.
J Urol ; 187(1): 109-16, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22088340

RESUMO

PURPOSE: We evaluated our retrospective, single institution experience with high dose rate brachytherapy as monotherapy for intermediate risk prostate cancer. MATERIALS AND METHODS: Our cohort included 284 patients with intermediate risk prostate cancer, defined as clinical stage T2b/T2c, Gleason score 7 and/or prostate specific antigen 10 to 20 ng/ml, and 1-year minimum followup. Treatment was 2 high dose rate brachytherapy sessions at 3 fractions of 6.5 Gy each for a mean of 19 days. Prostate specific antigen failure was defined as nadir +2 ng/ml. RESULTS: Mean followup was 35.1 months (median 31.9). Actuarial 5-year cause specific survival and clinical local control were 100%, distant-metastasis-free survival 98.8% and biochemical disease-free survival 94.4%. Clinical stage predicted biochemical disease-free survival. For stage T2a or less 5-year biochemical disease-free survival was 95.1% vs 100% for stage T2b and 77.4% for T2c (p = 0.012). Percent positive biopsy cores and prostate specific antigen nadir were also predictive. International Prostate Symptom Score results remained stable and potency was maintained in 82.6% of patients at 2 years. Pads were used for the first time after brachytherapy in 22 patients (7.7%), mostly for grade 1 incontinence (occasionally or less per week). Excluding patients with prior transurethral prostatectomy, stroke or tremor 2.5% used pads for the first time after treatment. No patient had urethral stricture. Radiation Therapy Oncology Group grade 1 rectal toxicity developed in 12 patients (4.2%) but not beyond grade 1. CONCLUSIONS: High dose rate brachytherapy as monotherapy is safe and effective for patients with intermediate risk prostate cancer. We recommend caution for percent positive biopsy cores exceeding 75% or clinical stage T2c. Excluding such patients the 5-year biochemical disease-free survival rate was 97.5%.


Assuntos
Braquiterapia/métodos , Neoplasias da Próstata/radioterapia , Idoso , Idoso de 80 Anos ou mais , Braquiterapia/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Dosagem Radioterapêutica , Estudos Retrospectivos , Fatores de Risco
6.
Fam Cancer ; 10(2): 349-53, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21188539

RESUMO

Chromosome translocations involving chromosome 3 have previously been associated with the development of renal cell carcinoma. In this report we describe an Ashkenazi Jewish family with a previously unreported balanced constitutional translocation (t(2;3)(q37.3;q13.2)) segregating with the development of clear cell renal carcinomata in three family members spanning two generations. We outline the difficulties with the clinical utility of this finding for genetic counselling and risk management strategies. We suggest that an additional renal cancer susceptibility gene may exist at 3q13.2, and review known breakpoints in the autosomes which are associated with clear cell renal cell carcinoma.


Assuntos
Carcinoma de Células Renais/genética , Cromossomos Humanos Par 2 , Cromossomos Humanos Par 3 , Judeus , Neoplasias Renais/genética , Translocação Genética , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem
7.
Br J Ophthalmol ; 94(1): 85-7, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19628488

RESUMO

OBJECTIVE: To evaluate the influence of socio-economic factors on severity of glaucoma at presentation METHODS: All newly diagnosed glaucoma patients at the University Hospitals-NHS, Aberdeen and South Glasgow University Hospitals-NHS, in 2006, were included. Glaucoma was severe at presentation if there was a repeatable visual-field loss with a mean deviation index greater than 12 dB in the Humphreys visual fields test or an absolute paracentral scotoma within the central 5 degrees of the visual fields. Home address was used to determine the Scottish Index of Multiple Deprivation (SIMD) rank. The SIMD rank, demographics and severity of glaucoma at presentation were investigated using general linear modelling. RESULTS: There were 48 patients with severe glaucoma and 74 patients with non-severe glaucoma. In four, the severity could not be determined. Severity of glaucoma at presentation was significantly associated with SIMD rank, being most severe in patients from areas with the lowest ranks (p = 0.026). Age was a significant factor (p = 0.024), with severe glaucoma being more common in elderly patients. CONCLUSIONS: Age and socio-economic deprivation were associated with severity of glaucoma at presentation, with patients from areas of higher socio-economic deprivation presenting with more advanced glaucoma.


Assuntos
Glaucoma/epidemiologia , Áreas de Pobreza , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Glaucoma/complicações , Glaucoma/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Escócia/epidemiologia , Escotoma/epidemiologia , Escotoma/etiologia , Índice de Gravidade de Doença , Fatores Socioeconômicos , Transtornos da Visão/epidemiologia , Transtornos da Visão/etiologia , Transtornos da Visão/fisiopatologia , Campos Visuais
8.
J Contam Hydrol ; 91(3-4): 267-87, 2007 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-17197052

RESUMO

Strontium-90 has migrated deep into the unsaturated subsurface beneath leaking storage tanks in the Waste Management Areas (WMA) at the U.S. Department of Energy's (DOE) Hanford Reservation. Faster than expected transport of contaminants in the vadose zone is typically attributed to either physical hydrologic processes such as development of preferential flow pathways, or to geochemical processes such as the formation of stable, anionic complexes with organic chelates, e.g., ethylenediaminetetraacetic acid (EDTA). The goal of this paper is to determine whether hydrological processes in the Hanford sediments can influence the geochemistry of the system and hence control transport of Sr(2+) and SrEDTA(2-). The study used batch isotherms, saturated packed column experiments, and an unsaturated transport experiment in an undisturbed core. Isotherms and repacked column experiments suggested that the SrEDTA(2-) complex was unstable in the presence of Hanford sediments, resulting in dissociation and transport of Sr(2+) as a divalent cation. A decrease in sorption with increasing solid:solution ratio for Sr(2+) and SrEDTA(2-) suggested mineral dissolution resulted in competition for sorption sites and the formation of stable aqueous complexes. This was confirmed by detection of MgEDTA(2-), MnEDTA(2-), PbEDTA(2-), and unidentified Sr and Ca complexes. Displacement of Sr(2+) through a partially-saturated undisturbed core resulted in less retardation and more irreversible sorption than was observed in the saturated repacked columns, and model results suggested a significant reservoir (49%) of immobile water was present during transport through the heterogeneous layered sediments. The undisturbed core was subsequently disassembled along distinct bedding planes and subjected to sequential extractions. Strontium was unequally distributed between carbonates (49%), ion exchange sites (37%), and the oxide (14%) fraction. An inverse relationship between mass wetness and Sr suggested that sandy sediments of low water content constituted the immobile flow regime. Our results suggested that the sequestration of Sr(2+) in partially-saturated, heterogeneous sediments was most likely due to the formation of immobile water in drier regions having low hydraulic conductivities.


Assuntos
Ácido Edético/química , Modelos Teóricos , Poluentes Radioativos do Solo/química , Radioisótopos de Estrôncio/química , Movimentos da Água , Poluentes Radioativos da Água/química , Sedimentos Geológicos , Washington
9.
Ground Water ; 44(3): 406-14, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16681521

RESUMO

The objective of this study was to experimentally determine the influence of pore structure on the transport and dissolution of trichloroethylene (TCE) in clay-rich saprolite. In order to simulate a "spill," pure-phase TCE containing a water-insoluble fluorescent dye was injected into two heterogeneous 24-cm-diameter by 37-cm-long undisturbed columns of water-saturated saprolite. TCE entry occurred at capillary pressures of 2.7 and 4.0 kPa. Ten or 28 d after injection, the column was sliced horizontally into three sections and visually examined. The distribution of fluorescent dye indicated that pure-phase TCE migrated mainly through fractures in the shale saprolite and through fine root holes or other macropores in the limestone saprolite residuum. Analysis of saprolite subsamples indicated that TCE was present throughout much of the saprolite column but usually at concentrations less than the solubility of TCE. This spreading was caused by diffusion, which also contributed to the rapid dissolution of TCE in the fractures and macropores. Modeling was carried out using previously published dissolution and diffusion equations. The calculations confirm that rapid disappearance of immiscible TCE can occur in this type of material because of the small size of fracture or macropore openings and the high porosity of the fine-grained material. This study indicates that industrial solvents can readily enter fractures and macropores in otherwise very fine-grained subsoils and then rapidly dissolve and diffuse into the fine-pore structure, from which they may be very difficult to remove.


Assuntos
Sedimentos Geológicos , Tricloroetileno/análise , Poluentes Químicos da Água/análise , Difusão , Corantes Fluorescentes , Água Doce , Solubilidade
10.
J Dairy Sci ; 89(2): 429-43, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16428613

RESUMO

Cheddar cheese ripening involves the conversion of lactose to glucose and galactose or galactose-6-phosphate by starter and nonstarter lactic acid bacteria. Under ideal conditions (i.e., where bacteria grow under no stress of pH, water activity, and salt), these sugars are mainly converted to lactic acid. However, during ripening of cheese, survival and growth of bacteria occurs under the stressed condition of low pH, low water activity, and high salt content. This forces bacteria to use alternate biochemical pathways resulting in production of other organic acids. The objective of this study was to determine if the level and type of organic acids produced during ripening was influenced by calcium (Ca) and phosphorus (P), residual lactose, and salt-to-moisture ratio (S/M) of cheese. Eight cheeses with 2 levels of Ca and P (0.67 and 0.47% vs. 0.53 and 0.39%, respectively), lactose at pressing (2.4 vs. 0.78%), and S/M (6.4 vs. 4.8%) were manufactured. The cheeses were analyzed for organic acids (citric, orotic, pyruvic, lactic, formic, uric, acetic, propanoic, and butyric acids) and residual sugars (lactose, galactose) during 48 wk of ripening using an HPLC-based method. Different factors influenced changes in concentration of residual sugars and organic acids during ripening and are discussed in detail. Our results indicated that the largest decrease in lactose and the largest increase in lactic acid occurred between salting and d 1 of ripening. It was interesting to observe that although the lactose content in cheese was influenced by several factors (Ca and P, residual lactose, and S/M), the concentration of lactic acid was influenced only by S/M. More lactic acid was produced in low S/M treatments compared with high S/M treatments. Although surprising for Cheddar cheese, a substantial amount (0.2 to 0.4%) of galactose was observed throughout ripening in all treatments. Minor changes in the levels of citric, uric, butyric, and propanoic acids were observed during early ripening, whereas during later ripening, a substantial increase was observed. A gradual decrease in orotic acid and a gradual increase in pyruvic acid content of the cheeses were observed during 12 mo of ripening. In contrast, acetic acid did not show a particular trend, indicating its role as an intermediate in a biochemical pathway, rather than a final product.


Assuntos
Cálcio/análise , Carboidratos/análise , Ácidos Carboxílicos/análise , Queijo/análise , Lactose/análise , Fósforo/análise , Ácido Acético/análise , Ácido Butírico/análise , Cromatografia Líquida de Alta Pressão , Ácido Cítrico/análise , Fermentação , Manipulação de Alimentos/métodos , Formiatos/análise , Galactose/análise , Lactococcus/metabolismo , Ácido Orótico/análise , Ácido Pirúvico/análise , Controle de Qualidade , Cloreto de Sódio/análise , Solubilidade , Fatores de Tempo , Ácido Úrico/análise , Água/análise
12.
J Small Anim Pract ; 45(11): 568-71, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15553196

RESUMO

Juvenile nephropathy has been documented in many breeds. Two related Pembroke Welsh corgi puppies presented at three and five months of age, respectively, for evaluation of lethargy, diarrhoea, poor body condition, polyuria and proteinuria. Based upon the clinical presentation, urinalysis and serum biochemistry, chronic renal failure was diagnosed. Renal histopathology was consistent with juvenile nephropathy, revealing lesions similar to the juvenile renal disease of dobermann dogs. To the authors' knowledge, this is the first report of juvenile nephropathy in related Pembroke Welsh corgi dogs. Familial nephropathy should now be considered as a differential diagnosis in cases of young Pembroke Welsh corgi dogs presenting with clinical signs indicating renal failure.


Assuntos
Doenças do Cão/diagnóstico , Falência Renal Crônica/veterinária , Rim/patologia , Animais , Análise Química do Sangue/veterinária , Cruzamento , Diagnóstico Diferencial , Doenças do Cão/genética , Doenças do Cão/patologia , Cães , Evolução Fatal , Falência Renal Crônica/diagnóstico , Falência Renal Crônica/genética , Falência Renal Crônica/patologia , Masculino
13.
J Contam Hydrol ; 64(3-4): 151-68, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12814878

RESUMO

This paper describes one of the first well-documented field examples of natural attenuation of trichloroethylene (TCE) in groundwater in a fractured shale bedrock. The study was carried out adjacent to a former waste burial site in Waste Area Grouping 5 (WAG5) on the Oak Ridge Reservation, Oak Ridge, TN. A contaminant plume containing TCE and its daughter products were detected downgradient from the buried waste pits, with most of the contamination occurring in the upper 6 m of the bedrock. The monitoring well array consists of a 35-m-long transect of multilevel sampling wells, situated along a line between the waste pits and a seep which discharges into a small stream. Concentrations of volatile organic carbons (VOCs) were highest in the waste trenches and decreased with distance downgradient towards the seep. Sampling wells indicated the presence of overlapping plumes of TCE, cis-dichloroethylene (cDCE), vinyl chloride (VC), ethylene, ethane, and methane, with the daughter products extending further downgradient than the parent (TCE). This type of distribution suggests anaerobic biodegradation. Measurements of redox potential at the site indicated that iron-reduction, sulfate reduction, and potentially methanogensis were occurring and are conducive to dechlorination of TCE. Bacteria enrichment of groundwater samples revealed the presence of methanotrophs, methanogens, iron-reducing bacteria and sulfate-reducing bacteria, all of which have previously been implicated in anaerobic biodegradation of TCE. 16S rDNA sequence from DNA extracted from two wells were similar to sequences of organisms previously implicated in the anaerobic biodegradation of chlorinated solvents. The combined data strongly suggest that anaerobic biodegradation of the highly chlorinated compounds is occurring. Aerobic biodegradation may also be occurring in oxygenated zones, including near a seep where groundwater exits the site, or in the upper bedrock during seasonal fluctuations in water table elevation and oxygen levels.


Assuntos
Poluentes do Solo/análise , Solventes/análise , Tricloroetileno/análise , Poluentes Químicos da Água/análise , Biodegradação Ambiental , Monitoramento Ambiental , Fenômenos Geológicos , Geologia , Microbiologia do Solo , Solventes/metabolismo , Tricloroetileno/metabolismo , Poluentes Químicos da Água/metabolismo
14.
J Appl Physiol (1985) ; 95(3): 1170-8, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12754178

RESUMO

To investigate the functional neuroanatomy of voluntary respiratory control, blood O2 level-dependent functional magnetic resonance imaging was performed in six healthy right-handed individuals during voluntary hyperpnea. Functional images of the whole brain were acquired during 30-s periods of spontaneous breathing alternated with 30-s periods of isocapnic hyperpnea [spontaneous vs. voluntary: tidal volume = 0.5 +/- 0.01 vs. 1.3 +/- 0.1 (SE) liters and breath duration = 4.0 +/- 0.4 vs. 3.2 +/- 0.4 (SE) s]. For the group, voluntary hyperpnea was associated with significant (P < 0.05, corrected for multiple comparisons) neural activity bilaterally in the primary sensory and motor cortices, supplementary motor area, cerebellum, thalamus, caudate nucleus, and globus pallidum. Significant increases in activity were also identified in the medulla (corrected for multiple comparisons on the basis of a small volume correction for a priori region of interest) in a superior dorsal position (P = 0.012). Activity within the medulla suggests that the brain stem respiratory centers may have a role in mediating the voluntary control of breathing in humans.


Assuntos
Fenômenos Fisiológicos do Sistema Nervoso , Respiração , Mecânica Respiratória/fisiologia , Adulto , Comportamento/fisiologia , Encéfalo/fisiologia , Química Encefálica/fisiologia , Tronco Encefálico/fisiologia , Dióxido de Carbono/sangue , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Bulbo/fisiologia , Consumo de Oxigênio/fisiologia , Tomografia Computadorizada de Emissão
16.
J Environ Qual ; 32(1): 129-37, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12549551

RESUMO

There are numerous Cr(III)-contaminated sites on Department of Defense (DoD) and Department of Energy (DOE) lands that are awaiting possible clean up and closure. Ingestion of contaminated soil by children is the risk driver that generally motivates the likelihood of site remediation. The purpose of this study was to develop a simple statistical model based on common soil properties to estimate the hioaccessibility of Cr(III)-contaminated soil upon ingestion. Thirty-five uncontaminated soils from seven major soil orders, whose properties were similar to numerous U.S. DoD contaminated sites, were treated with Cr(III) and aged. Statistical analysis revealed that Cr(III) sorption (e.g., adsorption and surface precipitation) by the soils was strongly correlated with the clay content, total inorganic C, pH, and the cation exchange capacity of the soils. Soils with higher quantities of clay, inorganic C (i.e., carbonates), higher pH, and higher cation exchange capacity generally sequestered more Cr(III). The amount of Cr(III) bioaccessible from the treated soils was determined with a physiologically based extraction test (PBET) that was designed to simulate the digestive process of the stomach. The bioaccessibility of Cr(III) varied widely as a function of soil type with most soils limiting bioaccessibility to <45 and <30% after I and 100 d soil-Cr aging, respectively. Statistical analysis showed the bioaccessibility of Cr(III) on soil was again related to the clay and total inorganic carbon (TIC) content of the soil. Bioaccessibility decreased as the soil TIC content increased and as the clay content decreased. The model yielded an equation based on common soil properties that could be used to predict the Cr(III) bioaccessibility in soils with a reasonable level of confidence.


Assuntos
Cromo/farmacocinética , Resíduos Perigosos , Modelos Estatísticos , Poluentes do Solo/farmacocinética , Adsorção , Silicatos de Alumínio/química , Disponibilidade Biológica , Carbono/química , Criança , Proteção da Criança , Cromo/química , Argila , Humanos , Concentração de Íons de Hidrogênio
17.
J Environ Qual ; 31(4): 1095-105, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12175026

RESUMO

The objective of this study was to investigate the influence of flow rate on transport and retention of bacteriophage tracers in a fractured shale saprolite, which is a highly weathered, fine-grained subsoil that retains much of the fabric of the parent bedrock. Synthetic ground water containing PRD-1, MS-2, and bromide was passed through a saturated column of undisturbed shale saprolite at rates ranging from 0.0075 to 0.96 m d '. First arrival of the bacteriophage tracers in effluent samples in each of the experiments occurred within 0.01 to 0.04 pore volumes (PV) of the start of injection, indicating that bacteriophage were advectively transported mainly through fractures or macropores. Bacteriophage transport velocities, based on first arrival in the effluent, were very similar to fracture flow velocities calculated using the cubic law for flow in a fractured material. For MS-2, maximum concentration and mass of tracer recovered both increased steadily as flow rate increased. For PRD-1, these values initially increased, but were nearly constant at flow rates above 0.039 m d(-1), indicating that approximately 50% of the observed losses were independent of flow rate. Evaluation of the data indicates that physical straining and electrostatic or hydrophobic attachment to fracture or macropore walls were the dominant retention processes. Inactivation and gravitational settling playing secondary roles, except at the slowest flow rates. The study suggests that microbial contamination from sources such as septic fields and sewage ponds may pose a threat to the quality of ground water and surface water in areas with saprolitic subsoils.


Assuntos
Bacteriófagos , Microbiologia do Solo , Monitoramento Ambiental , Fenômenos Geológicos , Geologia , Porosidade , Eliminação de Resíduos , Esgotos , Eletricidade Estática , Movimentos da Água
18.
Am J Obstet Gynecol ; 185(4): 959-65, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11641685

RESUMO

OBJECTIVE: To investigate the effect of cervical application of nonselective and selective inhibitors of nitric oxide synthases--N-nitro-L-arginine methyl ester, L-N-iminoethyl-lysine, and aminoguanidine--as well as inhibitors of cyclooxygenases--indomethacin, and nimesulide--on timing of delivery and fetal death and disease in pregnant rats. STUDY DESIGN: In a series of experimental protocols, timed-pregnant Sprague-Dawley rats (length of pregnancy, 22 days) were randomly allocated to daily cervical applications of (1) 0.04 mg (n = 6), 0.4 mg (n = 6), 4 mg (n = 6), or 40 mg (n = 6) L-N-iminoethyl-lysine or vehicle (n = 12) on days 19 to 22 of pregnancy; (2) 50 mg aminoguanidine (n = 6), 150 mg aminoguanidine (n = 6), or vehicle (n = 10) on days 19 to 22 of pregnancy; (3) 3 mg indomethacin (n = 6) or vehicle (n = 6) on days 19 to 22 of pregnancy; (4) 12.5 mg/kg nimesulide (n = 8), 25 mg/kg nimesulide (n = 8), 50 mg/kg nimesulide (n = 12), or vehicle (n = 12) on days 19 to 22 of pregnancy and 50 mg/kg nimesulide (n = 23) or vehicle (n = 23) on days 14 to 22 of pregnancy; (5) 50 mg/kg nimesulide (n = 10), 50 mg aminoguanidine plus 50 mg/kg nimesulide (n = 10), 50 mg aminoguanidine (n = 10), or vehicle (n = 10) on days 14 to 22 of pregnancy. The following variables were evaluated: proportion of animals that were delivered on day 23, time to delivery of the first pup (midnight on day 22 was considered to be 0 hour), number of stillborn pups, and average pup weight of each litter. RESULTS: Unlike L-N-iminoethyl-lysine, aminoguanidine, and indomethacin, 50 mg/kg nimesulide applied on the cervix daily for 8 days significantly increased the proportion of animals that were delivered on day 23 (18 of 23 versus 7 of 23; P =.003) and the time to delivery of the first pup by a mean of 10.8 hours (P <.001). Shorter treatment with nimesulide for 4 days increased only the time to delivery of the first pup at the 25-mg/kg dosage (P =.008). Simultaneous application of aminoguanidine and nimesulide significantly (P =.008) prolonged pregnancy to a degree similar to nimesulide alone. The experiment with N-nitro-L-arginine methyl ester was aborted because of severe maternal side effects. Unlike pups in the L-N-iminoethyl-lysine, aminoguanidine, and nimesulide groups, significantly more pups in the indomethacin group died in utero compared with the control group (36.1% versus 3.1%; P <.001), and the surviving pups had lower birth weights (P <.001). CONCLUSIONS: In an animal model, nimesulide was effective in delaying the onset of labor, was well tolerated during pregnancy, and affected cervical ripening directly independent of progesterone withdrawal. Conversely, cervical application of nitric oxide synthase and nonselective cyclooxygenase inhibitors do not extend the duration of pregnancy in the dosages studied, and some are associated with significant adverse effects in the mothers and fetuses.


Assuntos
Maturidade Cervical/efeitos dos fármacos , Inibidores de Ciclo-Oxigenase/farmacologia , Morte Fetal , Guanidinas/farmacologia , Indometacina/farmacologia , NG-Nitroarginina Metil Éster/administração & dosagem , Sulfonamidas/farmacologia , Administração Tópica , Animais , Colo do Útero/efeitos dos fármacos , Colo do Útero/fisiologia , Parto Obstétrico/métodos , Feminino , Modelos Animais , Gravidez , Resultado da Gravidez , Prenhez , Probabilidade , Ratos , Ratos Sprague-Dawley , Sensibilidade e Especificidade , Estatísticas não Paramétricas , Resultado do Tratamento
20.
Dynamics ; 12(4): 18-24, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11845483

RESUMO

The improvement in design and biocompatibility of continuous renal replacement therapy equipment has made it possible to perform therapeutic plasma exchange (TPE) in the intensive care unit. The purpose of this article is to outline the general principles of apheresis, including a historical perspective, current indications, and complications. Replacement fluid, membrane filtration, anticoagulation, and vascular access will be presented. A summary of the nursing care associated with TPE, potential complications, and methods to reduce the risk of their occurrence are summarized.


Assuntos
Troca Plasmática , Anticoagulantes/uso terapêutico , Cuidados Críticos , História do Século XX , Humanos , Cuidados de Enfermagem/métodos , Troca Plasmática/efeitos adversos , Troca Plasmática/história , Troca Plasmática/métodos , Troca Plasmática/enfermagem , Guias de Prática Clínica como Assunto , Fatores de Risco
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