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1.
Radiology ; 263(1): 139-48, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22344403

RESUMO

PURPOSE: To evaluate dynamic contrast-enhanced (DCE) magnetic resonance (MR) imaging for monitoring and assessing treatment response in patients with neuroendocrine liver metastases treated using yttrium 90 ((90)Y)-labeled octreotide ((90)Y-DOTATOC). MATERIALS AND METHODS: The study was approved by the local research and ethics committee and patient informed consent was obtained. Twenty patients with liver metastases from neuroendocrine tumors underwent T1-weighted DCE MR imaging of the liver before and at 2 months after intravenous (90)Y-DOTATOC treatment. Regions of interest were drawn around target lesions, as well as along liver outlines for each patient. A dual-input single-compartment model was used to compute parameters including fractional distribution volume and the arterial flow fraction. Pre- and posttreatment values were compared using Wilcoxon signed rank test. Treatment response was defined as showing a greater than 50% reduction in the nadir chromogranin A level within the 1st year after treatment. Pretreatment values of responders and nonresponders were compared using the Mann-Whitney test. A two-tailed P value of .008 or less, which accounts for multiple testing, was considered to indicate a significant difference. RESULTS: In responders, tumor and whole liver distribution volume significantly increased after treatment (median tumor distribution volume, 0.182 vs 0.244; median whole liver distribution volume, 0.175 vs 0.207; P = .008). The pretreatment whole liver distribution volume was significantly lower in responders (median, 0.175 vs 0.248; P = .003), while pretreatment tumor arterial flow fraction was significantly higher in responders (median, 1.000 vs 0.7 ± 1, P = .006). CONCLUSION: DCE MR imaging may be used to monitor the effects of peptide receptor radiolabeled targeted therapy in patients with neuroendocrine tumors liver metastases; a lower pretreatment distribution volume and high arterial flow fraction was associated with a better response to treatment.


Assuntos
Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/secundário , Imageamento por Ressonância Magnética/métodos , Tumores Neuroendócrinos/patologia , Octreotida/análogos & derivados , Compostos Radiofarmacêuticos/uso terapêutico , Adulto , Idoso , Área Sob a Curva , Meios de Contraste , Análise Discriminante , Feminino , Gadolínio DTPA , Humanos , Interpretação de Imagem Assistida por Computador , Neoplasias Hepáticas/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Octreotida/farmacocinética , Octreotida/uso terapêutico , Valor Preditivo dos Testes , Estudos Prospectivos , Compostos Radiofarmacêuticos/farmacocinética , Estatísticas não Paramétricas , Taxa de Sobrevida , Tomografia Computadorizada de Emissão de Fóton Único , Resultado do Tratamento
2.
Radiology ; 261(1): 182-92, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21828186

RESUMO

PURPOSE: To prospectively evaluate apparent diffusion coefficient (ADC) histograms in the prediction of chemotherapy response in patients with metastatic ovarian or primary peritoneal cancer. MATERIALS AND METHODS: Research ethics committee approval and patient written informed consent were obtained. Diffusion-weighted (DW) magnetic resonance (MR) imaging was performed through the abdomen and pelvis before and after one and three cycles of chemotherapy in 42 women (mean age, 63.0 years ± 11.4 [standard deviation]) with newly diagnosed or recurrent disease. Reproducibility and intra- and interobserver agreement of ADC calculations were assessed. Per-patient weighted ADC histograms were generated at each time point from pixel ADCs from five or fewer target lesions. Mean ADC, percentiles (10th, 25th, 50th, 75th, 90th), skew, kurtosis, and their change were analyzed according to histologic grade, primary versus recurrent disease status, and response, determined with integrated biochemical and morphologic criteria, with a linear mixed model. Areas under receiver operating characteristic curve (AUCs) for combinations of parameters were calculated with linear discriminant analysis. RESULTS: Coefficients of variation for repeat measurements and for within and between observers were 4.8%, 11.4%, and 13.7%, respectively. Grade and disease status did not significantly affect histogram parameters. Pretreatment ADCs were not predictive of response. In responders, all ADCs increased after the first and third cycle (P < .001), while skew and kurtosis decreased after the third (P < .001 and P = .006, respectively); however, in nonresponders, no parameter changed significantly. Percentage change of the 25th percentile performed best in identifying response (AUC = 0.82 and 0.83 after first and third cycle, respectively), whereas combination of parameters did not improve accuracy. CONCLUSION: An early increase of ADCs and later decrease of skew and kurtosis characterize chemotherapy response. Quantitative DW MR imaging can aid in early monitoring of treatment efficacy in patients with advanced ovarian cancer.


Assuntos
Imagem de Difusão por Ressonância Magnética , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia , Neoplasias Peritoneais/tratamento farmacológico , Neoplasias Peritoneais/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pessoa de Meia-Idade , Metástase Neoplásica , Estudos Prospectivos , Resultado do Tratamento
3.
PLoS One ; 12(11): e0187278, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29135991

RESUMO

Subjective well-being includes 'affect' and 'satisfaction with life' (SWL). This study proposes a unified approach to construct a profile of subjective well-being based on social media language in Facebook status updates. We apply sentiment analysis to generate users' affect scores, and train a random forest model to predict SWL using affect scores and other language features of the status updates. Results show that: the computer-selected features resemble the key predictors of SWL as identified in early studies; the machine-predicted SWL is moderately correlated with the self-reported SWL (r = 0.36, p < 0.01), indicating that language-based assessment can constitute valid SWL measures; the machine-assessed affect scores resemble those reported in a previous experimental study; and the machine-predicted subjective well-being profile can also reflect other psychological traits like depression (r = 0.24, p < 0.01). This study provides important insights for psychological prediction using multiple, machine-assessed components and longitudinal or dense psychological assessment using social media language.


Assuntos
Satisfação Pessoal , Mídias Sociais , Humanos , Aprendizado de Máquina , Modelos Teóricos
4.
Nat Commun ; 8: 13994, 2017 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-28067268

RESUMO

Physiological responses to temperature are known to be a major determinant of species distributions and can dictate the sensitivity of populations to global warming. In contrast, little is known about how other major global change drivers, such as ocean acidification (OA), will shape species distributions in the future. Here, by integrating population genetics with experimental data for growth and mineralization, physiology and metabolomics, we demonstrate that the sensitivity of populations of the gastropod Littorina littorea to future OA is shaped by regional adaptation. Individuals from populations towards the edges of the natural latitudinal range in the Northeast Atlantic exhibit greater shell dissolution and the inability to upregulate their metabolism when exposed to low pH, thus appearing most sensitive to low seawater pH. Our results suggest that future levels of OA could mediate temperature-driven shifts in species distributions, thereby influencing future biogeography and the functioning of marine ecosystems.

5.
Gigascience ; 5: 10, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26913198

RESUMO

BACKGROUND: Metabolomics is increasingly recognized as an invaluable tool in the biological, medical and environmental sciences yet lags behind the methodological maturity of other omics fields. To achieve its full potential, including the integration of multiple omics modalities, the accessibility, standardization and reproducibility of computational metabolomics tools must be improved significantly. RESULTS: Here we present our end-to-end mass spectrometry metabolomics workflow in the widely used platform, Galaxy. Named Galaxy-M, our workflow has been developed for both direct infusion mass spectrometry (DIMS) and liquid chromatography mass spectrometry (LC-MS) metabolomics. The range of tools presented spans from processing of raw data, e.g. peak picking and alignment, through data cleansing, e.g. missing value imputation, to preparation for statistical analysis, e.g. normalization and scaling, and principal components analysis (PCA) with associated statistical evaluation. We demonstrate the ease of using these Galaxy workflows via the analysis of DIMS and LC-MS datasets, and provide PCA scores and associated statistics to help other users to ensure that they can accurately repeat the processing and analysis of these two datasets. Galaxy and data are all provided pre-installed in a virtual machine (VM) that can be downloaded from the GigaDB repository. Additionally, source code, executables and installation instructions are available from GitHub. CONCLUSIONS: The Galaxy platform has enabled us to produce an easily accessible and reproducible computational metabolomics workflow. More tools could be added by the community to expand its functionality. We recommend that Galaxy-M workflow files are included within the supplementary information of publications, enabling metabolomics studies to achieve greater reproducibility.


Assuntos
Cromatografia Líquida/métodos , Biologia Computacional/métodos , Espectrometria de Massas/métodos , Metabolômica/métodos , Software , Metaboloma , Análise de Componente Principal , Reprodutibilidade dos Testes , Fluxo de Trabalho
6.
Am J Kidney Dis ; 39(3): 549-55, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11877574

RESUMO

National Kidney Foundation-Dialysis Outcomes Quality Initiative (NKF-DOQI) Vascular Access Guidelines 29 (40% of prevalent patients should have a native fistula) and 30 (<10% use of catheters for chronic hemodialysis) are currently based on opinion, rather than published evidence. The impact of these guidelines on reducing vascular access infection rates is unknown and was tested using data from an outpatient prospective cohort analysis. Patients undergoing hemodialysis from January 1998 through December 2000 at six outpatient facilities in Idaho and Oregon were evaluated prospectively for vascular access infections. There were 111,383 dialysis sessions (DSs) with 471 infections identified (4.2 infections/1,000 DSs). The risk for infection relative to arteriovenous (AV) fistulae was highly dependent on type of access used: 2.2 (P = 0.002) for AV grafts, 13.6 (P < 0.0001) for tunneled catheters, and 32.6 (P < 0.0001) for temporary catheters. Based on incidence infection rates, the number of infections predicted to occur with implementation of guidelines 29 and 30 in this population was calculated, and the percentage of reduction in infection was determined. Following either guideline 29 or 30 alone would have predictably prevented 103 or 97 total infections (22% and 21% reduction) and 40 or 51 bloodstream infections (24% and 30% reduction), respectively. Following both guidelines simultaneously would have prevented 151 total infections (32% reduction) and 64 bloodstream infections (38% reduction). These epidemiological data firmly establish that a major risk for vascular access infections is the type of access used (temporary catheters > tunneled catheters > AV grafts > AV fistulae). Furthermore, they strongly support the role of these NKF-DOQI guidelines in preventing infectious complications attributed to vascular access.


Assuntos
Derivação Arteriovenosa Cirúrgica/efeitos adversos , Infecções/epidemiologia , Guias de Prática Clínica como Assunto/normas , Diálise Renal/métodos , Bacteriemia/epidemiologia , Medicina Baseada em Evidências , Humanos , Controle de Infecções , Vigilância da População , Estudos Prospectivos , Diálise Renal/efeitos adversos , Fatores de Risco , Estados Unidos/epidemiologia
7.
Infect Control Hosp Epidemiol ; 23(9): 538-41, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12269453

RESUMO

OBJECTIVE: To describe an outbreak of infections with permanent cuffed hemodialysis catheters recognized through ongoing surveillance and related to a specific malfunctioning permanent catheter. DESIGN: The outbreak was suspected from the results of prospective infection surveillance and confirmed by a retrospective cohort study using medical records for patients receiving dialysis between April 1, 1999, and March 31, 2000. SETTING: Integrated network of six outpatient hemodialysis facilities in southern Idaho and eastern Oregon. PATIENTS: Outpatients receiving long-term hemodialysis. RESULTS: During the 18 months prior to the outbreak, the overall infection rate was 4.1 infections per 1,000 dialysis sessions with a catheter rate of 8.9 per 1,000 dialysis sessions. During the 7 months of the outbreak, the overall rate increased to 5.8 per 1,000 dialysis sessions, whereas the catheter rate increased to 18.1 per 1,000 dialysis sessions. Reports of malfunctioning "Brand A" catheters prompted discontinuation of their placement. A manufacturer recall occurred in April 2000. During the 14 months after the outbreak, the overall infection rate decreased to 3.3 per 1,000 dialysis sessions and the catheter rate to 10.8 per 1,000 dialysis sessions. A 12-month retrospective cohort study recognized 96 patients with an identifiable catheter brand and 48 infections. Of these, 27 (56%) occurred in patients with Brand A catheters. The relative risk for infection when compared with other catheter brands was 1.96 (95% confidence interval, 1.32 to 2.92; P < .001). CONCLUSIONS: Ongoing infection surveillance in hemodialysis facilities can identify specific device-related outbreaks of infections and promote interventions to reduce infectious complications and promote patient safety. Surveillance for vascular access site infections is recommended as a routine activity in hemodialysis facilities.


Assuntos
Cateteres de Demora/efeitos adversos , Infecção Hospitalar/etiologia , Surtos de Doenças/estatística & dados numéricos , Controle de Infecções/métodos , Diálise Renal/instrumentação , Estudos de Coortes , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/prevenção & controle , Surtos de Doenças/prevenção & controle , Falha de Equipamento , Humanos , Idaho/epidemiologia , Oregon/epidemiologia , Vigilância da População , Estudos Prospectivos , Estudos Retrospectivos , Risco , Fatores de Risco
8.
Zookeys ; (147): 487-96, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22379389

RESUMO

Bembidion (Lymnaeum) nigropiceum (Marsham) (=puritanum Hayward), a European species introduced into Massachusetts but presumed not to have become established, has been rediscovered during the Boston Harbor Islands All Taxa Biodiversity Inventory undertaken by the Museum of Comparative Zoology and the National Park Service. A summary is presented of treatment of this species in North America. Data on specimens collected are presented, along with observations on habitat and biology. Some speculations are presented about its highly specialized habitat in the gravel pushed up by high tide, which may act as a food-trapping sieve. A few words are included about future actions needed to resolve questions of distribution and behavior.

9.
Zookeys ; (147): 85-97, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22379386

RESUMO

A new species, Tetracha (Neotetracha) naviauxi, and a new subspecies, Tetracha (Tetracha) sobrina caicosensis, are described from the Turks and Caicos Islands. The key to Tetracha species in Naviaux (2007) is adapted to accommodate Tetracha naviauxi. Tetracha sobrina caicosensis is compared to other Caribbean subspecies of Tetracha sobrina.

10.
Zookeys ; (147): 497-526, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22371673

RESUMO

As part of an All Taxa Biodiversity Inventory in Boston Harbor Islands national park area, an inventory of carabid beetles on 13 islands was conducted. Intensive sampling on ten of the islands, using an assortment of passive traps and limited hand collecting, resulted in the capture of 6,194 specimens, comprising 128 species. Among these species were seven new state records for Massachusetts (Acupalpus nanellus,Amara aulica,Amara bifrons, Apenes lucidulus, Bradycellus tantillus, Harpalus rubripes and Laemostenus terricola terricola-the last also a new country record; in passing we report also new state records for Harpalus rubripes from New York and Pennsylvania, Amara ovata from Pennsylvania, and the first mainland New York records for Asaphidion curtum). For most islands, there was a clear relationship between species richness and island area. Two islands, however, Calf and Grape, had far more species than their relatively small size would predict. Freshwater marshes on these islands, along with a suite of hygrophilous species, suggested that habitat diversity plays an important role in island species richness. Introduced species (18) comprised 14.0% of the total observed species richness, compared to 5.5% (17 out of 306 species) documented for Rhode Island. We surmise that the higher proportion of introduced species on the islands is, in part, due to a higher proportion of disturbed and open habitats as well as high rates of human traffic. We predict that more active sampling in specialized habitats would bring the total carabid fauna of the Boston Harbor Islands closer to that of Rhode Island or eastern Massachusetts in richness and composition; however, isolation, human disturbance and traffic, and limited habitat diversity all contribute to reducing the species pool on the islands relative to that on the mainland.

11.
Zookeys ; (147): 3-13, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22371660

RESUMO

The lives and contributions of Ross and Joyce Bell are described with particular attention to studies of invertebrate natural history in the state of Vermont and carabid beetles of several groups, including the world rhysodine fauna. Their work, all done at the University of Vermont, was mainly taxonomic in nature and included aspects of the biology of the species considered. During their careers they described more than 75% of the c. 340 rhysodine species known to science. Ross Bell also wrote a number of seminal papers about the basal relationships of the Adephaga and the comparative anatomy of carabid coxal cavities. Ross and Joyce inspired several generations of students at UVM to take up advanced work in entomology and natural history.

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