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1.
Phys Chem Chem Phys ; 2020 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-32406445

RESUMO

Aqueous nitrate is ubiquitous in the environment, found for example in stratospheric clouds, tropospheric particulate matter, rain and snow, fertilized fields, rivers and the ocean. Its photolysis is initiated by absorption into the strongly forbidden n → π* transition. Photolysis reactivates deposited nitrate, releasing nitrogen oxides, and UV light is commonly used to break down nitrate pollution. The transition is doubly forbidden unless its symmetry is broken, giving a powerful means of probing the interactions of nitrate with its environment and of using experiment to validate the results of theory. In this study we demonstrate the remarkably different effects of the addition of a series of mono- and di-valent metal chlorides on the nitrate UV transition. While they all shift the transition to shorter wavelengths, the shift changes significantly from one to another. For the monovalent series Li+, Na+, K+, the blue shift decreases down the column being strongest for Li+ and weakest for K+. For the divalent series Mg2+, Ca2+, Ba2+, the opposite effect is observed with the energy shift of Ba2+ being an order of magnitude larger than for Mg2+. The absorption intensity also changes; the addition of Na+ and K+ decrease intensity whereas Li+ increases intensity. For the divalent cations an increase is seen for all three members of the series Mg2+, Ca2+ and Ba2+. Paradoxically, the effect of addition of CaCl2 to the solution is to decrease the environmental photolysis rate of nitrate; despite the increase in intensity, Ca2+ blue shifts the peak position above the tropospheric photolysis threshold around 300 nm. Using computational chemistry we conclude that the effects are due to the microscopic interactions of the nitrate anion and not continuum effects. Two microscopic mechanisms are investigated in detail, the formation of a nitrate monohydrate cluster and a contact ion pair. The contact ion pair shows the potential for significant impact on the energy and intensity of the transition.

2.
J Vasc Surg Venous Lymphat Disord ; 8(2): 187-194.e1, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31636051

RESUMO

BACKGROUND: Death from venous thromboembolism remains a significant cause of death worldwide. Although anticoagulation is the cornerstone of treatment in patients at risk for venous thromboembolism, inferior vena cava (IVC) filter use has increased exponentially over the last decade driven predominantly by the prophylactic use in patients at risk for venous thromboembolism despite limited evidence supporting this practice. The Predicting the Safety and Effectiveness of Inferior Vena Cava Filters (PRESERVE) Study is being implemented by the Society for Vascular Surgery, Society of Interventional Radiology, U.S. Food and Drug Administration, and several IVC filter manufactures to better understand the safety, effectiveness, and current patterns of real-world use of IVC filters. METHODS: The PRESERVE Study includes IVC filters from seven manufacturers: ALN (ALN ± hook), Argon (Option Elite), B. Braun (LP, Vena Tech Convertible), CR Bard (Denali), Cook (Gunther Tulip), Cordis (OptEase, TrapEase), and Philips Volcano (Crux). The indications for filter placement, filter brand, complications, stability, frequency and success of retrieval, and clinical effectiveness of each filter will be recorded. Approximately 2100 patients (300 for each filter brand included in the study) are intended to be enrolled at 60 U.S. centers. RESULTS: Men and women age 18 years or older requiring IVC filters for prevention of venous thromboembolism will be included in the study if no contrast allergy is present and they are willing to commit to the prescribed study follow-up. Participants will be evaluated at discharge, 3, 6, 12, 18, and 24 months after filter placement and/or 1 month after retrieval, which ever occurs first. Intravascular ultrasound examination or venography will be done before and after IVC filter placement, with abdominal plain film at 3 months, and contrast enhanced computed tomography scans at 12 and 24 months to evaluate filter stability. The primary safety end point is a composite of clinical end points, including freedom from perforation, embolization, thrombosis, recurrent DVT, and defined serious adverse events. Secondary end points include mechanical stability and procedure related complications at 3 months, major adverse events at 6, 12, 18, and 24 months, and filter tilt of more than 15° at any point. CONCLUSIONS: The PRESERVE Study represents the largest prospective study ever undertaken to investigate real-world outcomes with contemporary use of IVC filters. The investigators await results with the hope that it can improve patient care.

3.
J Vasc Interv Radiol ; 31(2): 221-230.e3, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31711748

RESUMO

PURPOSE: To report final 2-year outcomes with the Sentry bioconvertible inferior vena cava (IVC) filter in patients requiring temporary protection against pulmonary embolism (PE). MATERIALS AND METHODS: In a prospective multicenter trial, the Sentry filter was implanted in 129 patients with documented deep vein thrombosis (DVT) and/or PE (67.5%) or who were at temporary risk of developing DVT/PE (32.6%). Patients were monitored and bioconversion status ascertained by radiography, computed tomography (CT), and CT venography through 2 years. RESULTS: The composite primary 6-month endpoint of clinical success was achieved in 97.4% (111/114) of patients. The rate of new symptomatic PE was 0% (n = 126) through 1 year and 2.4% (n = 85) through the second year of follow-up, with 2 new nonfatal cases at 581 and 624 days that were adjudicated as not related to the procedure or device. Two patients (1.6%) developed symptomatic caval thrombosis during the first month and underwent successful interventions without recurrence. No other filter-related symptomatic complications occurred through 2 years. There was no filter tilting, migration, embolization, fracture, or caval perforation and no filter-related deaths through 2 years. Filter bioconversion was successful for 95.7% (110/115) of patients at 6 months, 96.4% (106/110) of patients at 12 months, and 96.5% (82/85) of patients at 24 months. Through 24 months of follow-up, there was no evidence of late-stage IVC obstruction or thrombosis after filter bioconversion or of thrombogenicity associated with retracted filter arms. CONCLUSIONS: The Sentry IVC filter provided safe and effective protection against PE, with a high rate of intended bioconversion and a low rate of device-related complications, through 2 years of follow-up.

4.
Sci Total Environ ; 704: 135325, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-31839317

RESUMO

Biotrickling filters (BTFs) applied to hydrophobic volatile organic compounds (VOCs) suffer from limited mass transfer. Phase transfer kinetic and equilibrium effects limit the biodegradation of hydrophobic VOCs especially at high concentrations. This study evaluates two strategies for overcoming the problem. First, a natural process was used to enhance the aqueous availability of styrene, a hydrophobic VOC model, by inoculating the BTF with a mixture of biosurfactant-generating bacteria. This method achieved a maximum elimination capacity (ECmax) of 139 g m-3h-1 in the BTF at an empty bed residence time (EBRT) of 60s. The highest concentrations of the biosurfactants surfactin and rhamnolipid were 205 and 86 mg L-1, respectively, in this step. Sequencing 16S rRNA confirmed the presence of biosurfactant-producing bacteria capable of biodegrading styrene in the BTF including Bacillus sonorensis, Bacillus subtilis, Lysinibacillus sphaericus, Lysinibacillus fusiformis, Alcaligenes feacalis, Arthrobacter creatinolyticus, and Kocuria rosea. Second, the effect of adding H2O2 to the recycle liquid on the BTF performance was determined. The biodegradation and mineralization of styrene in the BTF operated at a loading rate of 266 g m-3h-1 and H2O2/styrene molar ratio of 0.05 with EBRT as short as 15 s were 94% and 53%, respectively, with the EC of 250 g m-3h-1. High concentrations of antioxidant enzymes (peroxidase and catalase: 56 and 7 U gbiomass-1, respectively) were produced and biosurfactant generation was increased in this step, contributing to enhanced styrene biodegradation and mineralization. The styrene biodegradation and mineralization values in the BTF in the last day operated under similar conditions but without H2O2 were 11.4% and 5.3%, respectively. The bacterial population had no considerable change in the BTF after adding H2O2. Accordingly, stimulating the BTF inoculated with biosurfactant-generating bacteria with H2O2 is a promising strategy for improving the biodegradation of hydrophobic VOCs.


Assuntos
Poluentes Atmosféricos/metabolismo , Biodegradação Ambiental , Estireno/metabolismo , Poluentes Atmosféricos/análise , Reatores Biológicos , Peróxido de Hidrogênio , Estireno/análise , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/metabolismo
5.
Tech Vasc Interv Radiol ; 22(3): 154-161, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31623756

RESUMO

Endoscopy is a technique used by interventional radiology (IR) in only a few centers throughout the United States. When used by IR, endoscopy is most well-known for its role in the treatment of hepatobiliary disease. However, its use with relation to pathology involving the gastrointestinal, genitourinary, and musculoskeletal systems is gaining momentum among IR. The purpose of this article is to demonstrate the potential benefits of IR endoscopy in nonbiliary intervention. A literature review, not requiring IRB approval, was performed via PubMed and Ovid Medline databases using the search terms "interventional radiology-operated endoscopy," "interventional endoscopy," "interventional radiology," "genitourinary," and "gastrointestinal." Literature describing IR endoscopy involving the gastrointestinal, genitourinary, and musculoskeletal systems were identified and described. Nine peer-reviewed articles were identified. While few studies were identified, a general theme suggesting a synergistic relationship between IR and endoscopy was noted. More studies are needed to better understand the role of endoscopy as a technique in the IR suite.


Assuntos
Endoscopia/métodos , Doenças Urogenitais Femininas/terapia , Gastroenteropatias/terapia , Doenças Urogenitais Masculinas/terapia , Doenças Musculoesqueléticas/terapia , Radiografia Intervencionista/métodos , Adulto , Endoscopia/efeitos adversos , Endoscopia Gastrointestinal , Feminino , Doenças Urogenitais Femininas/diagnóstico por imagem , Gastroenteropatias/diagnóstico por imagem , Humanos , Masculino , Doenças Urogenitais Masculinas/diagnóstico por imagem , Doenças Musculoesqueléticas/diagnóstico por imagem , Radiografia Intervencionista/efeitos adversos , Resultado do Tratamento
6.
Phys Chem Chem Phys ; 21(42): 23466-23472, 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31616875

RESUMO

The environmentally relevant n →π* transition in the nitrate anion is doubly forbidden by symmetry, as the Franck-Condon and first order vibronic coupling terms are both zero in the gas phase. Inclusion of the second order vibronic coupling term is therefore essential when calculating the oscillator strength. Here we have calculated an oscillator strength of 5.7 × 10-6. The second order vibronic coupling term is included by manually displacing the ground-state geometry simultaneously along two normal modes, Ql and Qk, in 19 × 19 steps, and calculating the transition dipole moment at each point by TD-DFT/ωB97XD/aug-cc-pVTZ and fitting to a polynomial in order to evaluate the second derivative with respect to Ql and Qk. In the aqueous phase the high symmetry of NO3- is broken and the first order term is no longer forbidden. However, the calculated solvated geometry still resembles the gas phase geometry and the calculated first order term does not contribute significantly to the overall oscillator strength of 1.9 × 10-6. This is a rare example of higher order vibronic coupling being more important than the lowest order term.

7.
J Gastrointest Surg ; 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31485902

RESUMO

PURPOSE: Transjugular intrahepatic portosystemic shunt (TIPS) creation is most commonly performed for patients with refractory ascites or variceal hemorrhage. While TIPS have also been created prior to planned abdominal operation to decrease morbidity related to portal hypertension, there are limited data supporting its effectiveness in that indication. The goal of this study was to determine if preoperative TIPS creation allows for successful abdominal operation with limited morbidity. METHODS: A retrospective review of records of 22 consecutive patients who underwent TIPS creation for the specific indication of improving surgical candidacy, between 2011 and 2016, was performed. Clinical and serologic data were obtained for 21 patients (one patient was excluded since she was completely lost to follow-up after TIPS creation). The primary endpoint was whether patients underwent planned abdominal operation following TIPS. Operative outcomes and reasons that patients failed to undergo planned operation were examined as secondary endpoints. The mean age was 56.4 ± 8.8 years and the mean Child-Pugh and Model for End-Stage Liver Disease (MELD) scores were 7.2 ± 1.5 and 11.9 ± 4.3, respectively. RESULTS: TIPS creation was performed in all 21 patients with a 30-day mortality rate of 9.5%. Eleven patients (52.4%) subsequently underwent abdominal operation after which the 30-day postoperative mortality rate was 0%. One patient (9.1%) had major perioperative morbidity related to portal hypertension and presented with surgical wound dehiscence and infection requiring drain placement and antibiotic therapy. CONCLUSIONS: In this population, TIPS allowed successful abdominal operation in the majority of patients, with 30-day TIPS mortality of 9.5%, no perioperative mortality, and 9.1% major postoperative morbidity attributable to portal hypertension.

8.
Artigo em Inglês | MEDLINE | ID: mdl-31418458

RESUMO

According to Wollack and Schoenig (2018, The Sage encyclopedia of educational research, measurement, and evaluation. Thousand Oaks, CA: Sage, 260), benefiting from item preknowledge is one of the three broad types of test fraud that occur in educational assessments. We use tools from constrained statistical inference to suggest a new statistic that is based on item scores and response times and can be used to detect examinees who may have benefited from item preknowledge for the case when the set of compromised items is known. The asymptotic distribution of the new statistic under no preknowledge is proved to be a simple mixture of two χ2 distributions. We perform a detailed simulation study to show that the Type I error rate of the new statistic is very close to the nominal level and that the power of the new statistic is satisfactory in comparison to that of the existing statistics for detecting item preknowledge based on both item scores and response times. We also include a real data example to demonstrate the usefulness of the suggested statistic.

9.
Environ Sci Technol ; 53(16): 9636-9645, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31347357

RESUMO

California methane (CH4) emissions are quantified for three years from two tower networks and one aircraft campaign. We used backward trajectory simulations and a mesoscale Bayesian inverse model, initialized by three inventories, to achieve the emission quantification. Results show total statewide CH4 emissions of 2.05 ± 0.26 (at 95% confidence) Tg/yr, which is 1.14 to 1.47 times greater than the anthropogenic emission estimates by California Air Resource Board (CARB). Some of differences could be biogenic emissions, superemitter point sources, and other episodic emissions which may not be completely included in the CARB inventory. San Joaquin Valley (SJV) has the largest CH4 emissions (0.94 ± 0.18 Tg/yr), followed by the South Coast Air Basin, the Sacramento Valley, and the San Francisco Bay Area at 0.39 ± 0.18, 0.21 ± 0.04, and 0.16 ± 0.05 Tg/yr, respectively. The dairy and oil/gas production sources in the SJV contribute 0.44 ± 0.36 and 0.22 ± 0.23 Tg CH4/yr, respectively. This study has important policy implications for regulatory programs, as it provides a thorough multiyear evaluation of the emissions inventory using independent atmospheric measurements and investigates the utility of a complementary multiplatform approach in understanding the spatial and temporal patterns of CH4 emissions in the state and identifies opportunities for the expansion and applications of the monitoring network.


Assuntos
Poluentes Atmosféricos , Metano , Aeronaves , Teorema de Bayes , California , São Francisco
10.
Int J Vasc Med ; 2019: 5795148, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31263598

RESUMO

The Sentry inferior vena cava (IVC) filter is designed to provide temporary protection against pulmonary embolism (PE) during transient high-risk periods and then to bioconvert after 60 days after implantation. At the time of bioconversion, the device's nitinol arms retract from the filtering position into the caval wall. Subsequently, the stable stent-like nitinol frame is endothelialized. The Sentry bioconvertible IVC filter has been evaluated in a multicenter investigational-device-exemption pivotal trial (NCT01975090) of 129 patients with documented deep vein thrombosis (DVT) or PE, or at temporary risk of developing DVT or PE, and with contraindications to anticoagulation. Successful filter conversion was observed in 95.7% of patients at 6 months (110/115) and 96.4% at 12 months (106/110). Through 12 months, there were no cases of symptomatic PE. The rationale for development of the Sentry bioconvertible device includes the following considerations: (1) the period of highest risk of PE for the vast majority of patients occurs within the first 60 days after an index event, with most of the PEs occurring in the first 30 days; (2) the design of retrievable IVC filters to support their removal after a transitory high-PE-risk period has, in practice, been associated with insecure filter dynamics and time-dependent complications including tilting, fracture, embolization, migration, and IVC perforation; (3) most retrievable IVC filters are placed for temporary protection, but for a variety of reasons they are not removed in any more than half of implanted patients, and when removal is attempted, the procedure is not always successful even with advanced techniques; and (4) analysis of Medicare hospital data suggests that payment for the retrieval procedure does not routinely compensate for expense. The Sentry device is not intended for removal after bioconversion. In initial clinical use, complications have been limited. Long-term results for the Sentry bioconvertible IVC filter are anticipated soon.

11.
Cancers (Basel) ; 11(6)2019 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-31234476

RESUMO

Hepatocellular carcinoma (HCC) is a leading cause of new cancer diagnoses in the United States, with an incidence that is expected to rise. The etiology of HCC is varied and can lead to differences between patients in terms of presentation and natural history. Subsequently, physicians treating these patients need to consider a variety of disease and patient characteristics when they select from the many different treatment options that are available for these patients. At the same time, the treatment landscape for patients with HCC, particularly those with unresectable HCC, has been rapidly evolving as new, evidence-based options become available. The treatment plan for patients with HCC can include surgery, transplant, ablation, transarterial chemoembolization, transarterial radioembolization, radiation therapy, and/or systemic therapies. Implementing these different modalities, where the optimal sequence and/or combination has not been defined, requires coordination between physicians with different specialties, including interventional radiologists, hepatologists, and surgical and medical oncologists. As such, the implementation of a multidisciplinary team is necessary to develop a comprehensive care plan for patients, especially those with unresectable HCC.

12.
Sci Adv ; 5(5): eaau7671, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31049393

RESUMO

Atmospheric deposition is a source of potentially bioavailable iron (Fe) and thus can partially control biological productivity in large parts of the ocean. However, the explanation of observed high aerosol Fe solubility compared to that in soil particles is still controversial, as several hypotheses have been proposed to explain this observation. Here, a statistical analysis of aerosol Fe solubility estimated from four models and observations compiled from multiple field campaigns suggests that pyrogenic aerosols are the main sources of aerosols with high Fe solubility at low concentration. Additionally, we find that field data over the Southern Ocean display a much wider range in aerosol Fe solubility compared to the models, which indicate an underestimation of labile Fe concentrations by a factor of 15. These findings suggest that pyrogenic Fe-containing aerosols are important sources of atmospheric bioavailable Fe to the open ocean and crucial for predicting anthropogenic perturbations to marine productivity.

13.
ACG Case Rep J ; 5: e75, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30426033

RESUMO

Hepatic artery thrombosis is a concerning complication of orthotopic liver transplantation, and it most often occurs early in the posttransplant period. However, on rare occasions it can occur at a time remote from transplant. We present a case of ischemic cholangiopathy complicated by stricture and anastomotic bile leak from chronic hepatic artery thrombosis that occurred 11 years after the transplant. The initial biliary stenting helped with the resolution of the leak but she was found to have stones, sludge and copious pus at the time of stent exchange. Hepatic arteriography demonstrated complete occlusion of the transplant hepatic artery with periportal collaterals reconstituting intrahepatic hepatic arterial branches. The patient was subsequently referred for repeat liver transplantation.

14.
J Vasc Interv Radiol ; 29(10): 1350-1361.e4, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30177423

RESUMO

PURPOSE: To prospectively assess the Sentry bioconvertible inferior vena cava (IVC) filter in patients requiring temporary protection against pulmonary embolism (PE). MATERIALS AND METHODS: At 23 sites, 129 patients with documented deep vein thrombosis (DVT) or PE, or at temporary risk of developing DVT or PE, unable to use anticoagulation were enrolled. The primary end point was clinical success, including successful filter deployment, freedom from new symptomatic PE through 60 days before filter bioconversion, and 6-month freedom from filter-related complications. Patients were monitored by means of radiography, computerized tomography (CT), and CT venography to assess filtering configuration through 60 days, filter bioconversion, and incidence of PE and filter-related complications through 12 months. RESULTS: Clinical success was achieved in 111 of 114 evaluable patients (97.4%, 95% confidence interval [CI] 92.5%-99.1%). The rate of freedom from new symptomatic PE through 60 days was 100% (n = 129, 95% CI 97.1%-100.0%), and there were no cases of PE through 12 months for either therapeutic or prophylactic indications. Two patients (1.6%) developed symptomatic caval thrombosis during the first month; neither experienced recurrence after successful interventions. There was no filter tilting, migration, embolization, fracture, or caval perforation by the filter, and no filter-related death through 12 months. Filter bioconversion was successful for 95.7% (110/115) at 6 months and for 96.4% (106/110) at 12 months. CONCLUSIONS: The Sentry IVC filter provided safe and effective protection against PE, with a high rate of intended bioconversion and a low rate of device-related complications, through 12 months of imaging-intense follow-up.


Assuntos
Implantação de Prótese/instrumentação , Embolia Pulmonar/prevenção & controle , Embolia Pulmonar/terapia , Filtros de Veia Cava , Trombose Venosa/prevenção & controle , Trombose Venosa/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Bélgica , Chile , Angiografia por Tomografia Computadorizada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Flebografia/métodos , Complicações Pós-Operatórias/etiologia , Estudos Prospectivos , Desenho de Prótese , Implantação de Prótese/efeitos adversos , Embolia Pulmonar/diagnóstico por imagem , Embolia Pulmonar/etiologia , Recidiva , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Estados Unidos , Trombose Venosa/diagnóstico por imagem , Trombose Venosa/etiologia , Adulto Jovem
15.
Water Res ; 142: 26-45, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-29859390

RESUMO

The high concentrations of pharmaceuticals and personal care products (PPCP) that found in water in many locations are of concern. Among the available water treatment methods, heterogeneous photocatalysis using TiO2 is an emerging and viable technology to overcome the occurrence of PPCP in natural and waste water. The combination of carbonaceous materials (e.g., activated carbon, carbon nanotubes and graphene nanosheets) with TiO2, a recent development, gives significantly improved performance. In this article, we present a critical review of the development and fabrication of carbonaceous-TiO2 and its application to PPCP removal including its influence on water chemistry, and the relevant operational parameters. Finally, we present an analysis of current priorities in the ongoing research and development of carbonaceous-TiO2 for the photodegradation of PPCP.


Assuntos
Carbono/química , Cosméticos/química , Preparações Farmacêuticas/química , Titânio/química , Titânio/efeitos da radiação , Poluentes Químicos da Água/química , Purificação da Água/métodos , Catálise , Fotólise
16.
J Vasc Interv Radiol ; 29(6): 867-873, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29724518

RESUMO

PURPOSE: To evaluate the effectiveness and safety of yttrium-90 transarterial radioembolization (TARE) for the treatment of primary and metastatic soft tissue sarcoma (STS) of the liver. MATERIALS AND METHODS: A retrospective review of 39 patients with primary (n = 2) and metastatic (n = 37) hepatic STS treated with TARE at 4 institutions was performed. Fourteen STS subtypes were included, with leiomyosarcoma being the most common (51%). TARE with glass (22 patients) or resin (17 patients) microspheres was performed, with single lobe (17 patients) or bilobar treatment (22 patients) based on disease burden. Adverse events of treatment, overall survival (OS), and tumor response at 3, 6, and 12 months after TARE were assessed per the Response Evaluation Criteria in Solid Tumors. RESULTS: Fourteen patients demonstrated either partial or complete response to therapy, with an objective response rate of 36%. Thirty patients (77%) demonstrated disease control (DC)-either stable disease or response to treatment. Median OS was 30 months (95% confidence interval 12-43 months) for all patients. DC at 3 months was associated with an increased median OS (44 months) compared with progressive disease (PD) (7.5 months; P < .0001). Patients with DC at 6 months also demonstrated an increased median OS (38 months) compared to patients with PD (17 months; P = .0443). Substantial adverse events included 1 liver abscess, 1 gastric ulceration, and 1 pneumonitis. CONCLUSIONS: Patients with hepatic STS treated with TARE demonstrated a high rate of DC and a median OS of 30 months, which suggests a role for TARE in the palliation of hepatic STS.


Assuntos
Embolização Terapêutica/métodos , Neoplasias Hepáticas/radioterapia , Sarcoma/radioterapia , Idoso , Feminino , Humanos , Neoplasias Hepáticas/patologia , Masculino , Microesferas , Pessoa de Meia-Idade , Radiografia Intervencionista , Estudos Retrospectivos , Sarcoma/patologia , Taxa de Sobrevida , Resultado do Tratamento , Radioisótopos de Ítrio
17.
Radiology ; 288(3): 774-781, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29737954

RESUMO

Purpose To determine the frequency of hepatobiliary infections after transarterial radioembolization (TARE) with yttrium 90 (90Y) in patients with liver malignancy and a history of biliary intervention. Materials and Methods For this retrospective study, records of all consecutive patients with liver malignancy and history of biliary intervention treated with TARE at 14 centers between 2005 and 2015 were reviewed. Data regarding liver function, 90Y dosimetry, antibiotic prophylaxis, and bowel preparation prophylaxis were collected. Primary outcome was development of hepatobiliary infection. Results One hundred twenty-six patients (84 men, 42 women; mean age, 68.8 years) with primary (n = 39) or metastatic (n = 87) liver malignancy and history of biliary intervention underwent 180 procedures with glass (92 procedures) or resin (88 procedures) microspheres. Hepatobiliary infections (liver abscesses in nine patients, cholangitis in five patients) developed in 10 of the 126 patients (7.9%) after 11 of the 180 procedures (6.1%; nine of those procedures were performed with glass microspheres). All patients required hospitalization (median stay, 12 days; range, 2-113 days). Ten patients required percutaneous abscess drainage, three patients underwent endoscopic stent placement and stone removal, and one patient needed insertion of percutaneous biliary drains. Infections resolved in five patients, four patients died (two from infection and two from cancer progression while infection was being treated), and one patient continued to receive suppressive antibiotics. Use of glass microspheres (P = .02), previous liver resection or ablation (P = .02), and younger age (P = .003) were independently predictive of higher infection risk. Conclusion Infectious complications such as liver abscess and cholangitis are uncommon but serious complications of transarterial radioembolization with 90Y in patients with liver malignancy and a history of biliary intervention.


Assuntos
Braquiterapia/efeitos adversos , Carcinoma Hepatocelular/radioterapia , Colangite/etiologia , Abscesso Hepático/etiologia , Neoplasias Hepáticas/radioterapia , Radioisótopos de Ítrio/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Braquiterapia/métodos , Carcinoma Hepatocelular/complicações , Feminino , Vidro , Humanos , Fígado/microbiologia , Neoplasias Hepáticas/complicações , Masculino , Microesferas , Pessoa de Meia-Idade , Retratamento , Estudos Retrospectivos , Resultado do Tratamento
18.
Psychometrika ; 83(1): 182-202, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28836133

RESUMO

In educational and psychological measurement when short test forms are used, the asymptotic normality of the maximum likelihood estimator of the person parameter of item response models does not hold. As a result, hypothesis tests or confidence intervals of the person parameter based on the normal distribution are likely to be problematic. Inferences based on the exact distribution, on the other hand, do not suffer from this limitation. However, the computation involved for the exact distribution approach is often prohibitively expensive. In this paper, we propose a general framework for constructing hypothesis tests and confidence intervals for IRT models within the exponential family based on exact distribution. In addition, an efficient branch and bound algorithm for calculating the exact p value is introduced. The type-I error rate and statistical power of the proposed exact test as well as the coverage rate and the lengths of the associated confidence interval are examined through a simulation. We also demonstrate its practical use by analyzing three real data sets.


Assuntos
Intervalos de Confiança , Psicometria/métodos , Desempenho Acadêmico , Algoritmos , Simulação por Computador , Interpretação Estatística de Dados , Abastecimento de Alimentos , Humanos , Fatores de Tempo
19.
Clin Adv Hematol Oncol ; 15 Suppl 9(8): 1-20, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29036035

RESUMO

The treatment approach for hepatocellular carcinoma (HCC) depends on the stage and extent of disease, the severity of the underlying liver disease, and the overall performance status of the patient. Treatment consists of 4 main strategies: surgery (eg, resection and liver transplant), locoregional procedures (eg, ablation and transarterial embolization), systemic therapies, and best supportive care. For patients with early-stage tumors, surgical treatment or ablation can be curative. Patients with intermediate-stage disease can be candidates for embolization, administered as either transarterial chemoembolization (TACE) or transarterial radioembolization (TARE). Systemic therapy is reserved for patients with advanced or unresectable disease. For the past decade, the multitargeted kinase inhibitor sorafenib has been the only agent approved for unresectable HCC. This approval was followed by several clinical trials investigating other multitargeted kinase inhibitors, but none showed any benefit over single-agent sorafenib. Most patients progress after treatment with first-line sorafenib. In April 2017, the US Food and Drug Administration approved regorafenib for patients with HCC who have been previously treated with sorafenib. In a phase 3 trial, regorafenib significantly improved overall survival vs placebo. A consideration with systemic treatments is the proactive management of adverse events, including toxicities associated with the drugs and progression of liver disease.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Niacinamida/análogos & derivados , Compostos de Fenilureia/administração & dosagem , Piridinas/administração & dosagem , Carcinoma Hepatocelular/mortalidade , Ensaios Clínicos como Assunto , Intervalo Livre de Doença , Feminino , Humanos , Neoplasias Hepáticas/mortalidade , Masculino , Niacinamida/administração & dosagem , Sorafenibe , Taxa de Sobrevida
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