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1.
Pancreatology ; 16(2): 278-83, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26774205

RESUMO

BACKGROUND AND STUDY AIMS: Pancreatic duct (PD) disruptions occur as a result of different etiologies and can be managed medically, endoscopically, or surgically. The aim of this study was to provide an evaluation on the efficacy of endotherapy for treatment of PD disruption in a large cohort of patients and identify factors that predict successful treatment outcome. PATIENTS AND METHODS: We retrospectively evaluated consecutive patients who underwent endoscopic retrograde pancreatography (ERP) for transpapillary pancreatic stent placement for PD disruption from 2008 to 2013 at two tertiary referral institutions. PD disruption was defined as extravasation of contrast from the pancreatic duct as seen on ERP. Therapeutic success was defined by resolution of PD leak on ERP, clinical, and/or imaging evaluation. RESULTS: We evaluated 107 patients (58% male, mean age 53 years) with PD disruption. Etiologies of PD disruption were acute pancreatitis (36%), post-operative (31%), chronic pancreatitis (29%), and trauma (4%). PD disruption was successfully bridged by a stent in 45 (44%) patients. Two patients developed post-sphincterotomy bleeding, two had stent migration, and two patients died as a result of post-ERP related complications. Placement of a PD stent was successful in 103/107 (96%) patients. Therapeutic success was achieved in 80/107 (75%) patients. Non-acute pancreatitis etiologies and absence of complete duct disruption were independent predictors of therapeutic success. CONCLUSIONS: Endoscopic therapy using a transpapillary stent for PD disruption is safe and effective. Absence of complete duct disruption and non-AP etiologies determine a favorable endoscopic outcome.


Assuntos
Endoscopia Gastrointestinal/métodos , Ductos Pancreáticos/lesões , Ductos Pancreáticos/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pancreatite/complicações , Ferimentos e Lesões/complicações
2.
J Am Chem Soc ; 133(8): 2567-70, 2011 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-21291217

RESUMO

This article reports nonlinear optical measurements that quantify, for the first time directly and without labels, how many Mg(2+) cations are bound to DNA 21-mers covalently linked to fused silica/water interfaces maintained at pH 7 and 10 mM NaCl, and what the thermodynamics are of these interactions. The overall interaction of Mg(2+) with adenine, thymine, guanine, and cytosine is found to involve -10.0 ± 0.3, -11.2 ± 0.3, -14.0 ± 0.4, and -14.9 ± 0.4 kJ/mol, and nonspecific interactions with the phosphate and sugar backbone are found to contribute -21.0 ± 0.6 kJ/mol for each Mg(2+) ion bound. The specific and nonspecific contributions to the interaction energy of Mg(2+) with oligonucleotide single strands is found to be additive, which suggests that within the uncertainty of these surface-specific experiments, the Mg(2+) ions are evenly distributed over the oligomers and not isolated to the most strongly binding nucleobase. The nucleobases adenine and thymine are found to bind only three Mg(2+) ions per 21-mer oligonucleotide, while the bases cytosine and guanine are found to bind eleven Mg(2+) ions per 21-mer oligonucleotide.


Assuntos
Adenina/química , Citosina/química , Guanina/química , Magnésio/química , Nucleotídeos/química , Timina/química , Íons/química , Termodinâmica , Água/química
3.
Environ Sci Technol ; 44(15): 5862-7, 2010 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-20666558

RESUMO

The interactions of the trivalent metal cations Al(III), La(III), Gd(III), and Lu(III) with the silica/water interface were studied using the nonlinear optical technique of second harmonic generation (SHG). Specifically, the Eisenthal chi(3) technique was used to quantify the thermodynamics of trivalent ion adsorption to the bare fused silica surface. SHG adsorption isotherms were measured and fit with the triple layer surface complexation model to obtain adsorption free energies, binding constants, and interfacial charge densities. The adsorption free energy for Al(III) was found to be -37.2(5) kJ/mol, while the adsorption free energies for the three trivalent lanthanide cations ranged from -29.9(9) to -32.2(7) kJ/mol. Despite identical ionic charges, the metals under investigation displayed different affinities for the fused silica/water interface, and this finding is analyzed and interpreted in the context of size-dependent metal cation properties and metal ion speciation. The thermodynamic results from this work are valuable benchmarks for computer simulations of trivalent metal transport in the environment.


Assuntos
Alumínio/química , Poluentes Ambientais/química , Gadolínio/química , Lantânio/química , Lutécio/química , Cátions/química , Fenômenos Químicos , Modelos Químicos , Dióxido de Silício/química , Água/química
4.
J Phys Chem A ; 114(4): 1797-805, 2010 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-20050625

RESUMO

We report the first use of resonantly enhanced second harmonic generation (SHG) to study uranyl adsorption at a buried mineral oxide/water interface. Uranyl adsorption is studied in real-time, under flow conditions, and in the presence of environmentally relevant screening electrolyte concentrations. The in situ SHG spectrum of surface-bound uranyl reveals a well-defined resonance at 306 nm. By monitoring the SHG response at 306 nm, adsorption isotherms were collected for uranyl species at the fused silica/water interface at pH 7, and in the presence of aqueous carbonate. The measured adsorption free energies determined by the Langmuir isotherm are consistent with physisorption via hydrogen bonding. The speciation of the surface-active uranyl species at pH 7 was elucidated via a free energy versus interfacial potential analysis, which reveals that the uranyl adsorbates are either neutral or univalent cationic species. Complementary surface charge density data, obtained using the Eisenthal chi(3) technique, reveal that the charge on the ionic uranyl species adsorbing under the experimental conditions are positive. It is proposed that a mixture of neutral and univalent, cationic uranyl species is surface active at pH 7 and in the presence of carbonate ions. Insofar as the experimental conditions model those found in natural groundwater systems, the results of this work are valuable to the prediction and assessment of uranium pollution transport in groundwater and soils. Our thermodynamic results can also serve as important benchmarks for computer simulations of U(VI) transport in heterogeneous geochemical environments.

5.
J Bronchology Interv Pulmonol ; 19(3): 200-2, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23207461

RESUMO

Endobronchial Hodgkin disease (HD) is very rare. We report the case of a women who presented with life-threatening airway obstruction. She was diagnosed with HD 4 years earlier and was in remission after treatment with a combination of chemotherapy and radiation. Bronchoscopy showed a polypoid mass obstructing the tracheal lumen almost completely. The mass was resected using an electrocautery snare loop, providing immediate relief of symptoms. Pathology and staging investigations revealed HD isolated to the trachea. This presentation and treatment is extremely unique for HD.


Assuntos
Obstrução das Vias Respiratórias/cirurgia , Doença de Hodgkin/cirurgia , Neoplasias da Traqueia/cirurgia , Obstrução das Vias Respiratórias/diagnóstico por imagem , Broncoscopia , Eletrocoagulação/métodos , Feminino , Doença de Hodgkin/diagnóstico por imagem , Humanos , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X , Neoplasias da Traqueia/diagnóstico por imagem
6.
J Interv Gastroenterol ; 2(4): 161-167, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23687602

RESUMO

BACKGROUND: The Tokyo Guidelines have greatly impacted the management of ascending cholangitis. Though ERCP is the favored modality for biliary decompression, no evidence exists for the timing of ERCP. The DEIM-I study set out to determine if the time from patient presentation to biliary decompression impacted in hospital all cause mortality in ascending cholangitis. METHOD: DEIM-I cohort study was a single-blinded and consisted of 250 subjects with moderate to severe ascending cholangitis who underwent ERCP/PBD. Subjects were randomized into quartiles based upon time from presentation until ERCP/PBD. The primary outcome utilized logistic regression to estimate relative risk (RR) of all cause, in hospital mortality with time to procedure as the predictive covariate. Secondary outcomes were analyzed using multivariate logistic regression and included; multiple organ failure (MOF), sepsis, systemic inflammatory response syndrome (SIRS), surgical incidence, hospital readmission and length of stay (LOS). RESULTS: The risk for hospital mortality was significantly less when biliary drainage was performed within 11 h, compared to >42 h (RR 0.34, 95%CI 0.12 to 0.99, p=0.049). Hospital readmission was lower in subjects who underwent biliary decompression less than 11 h, when compared to those greater than 22 h. Subjects who underwent biliary decompression within 21 h had significant higher risk for surgery compared to those 22-42 h. CONCLUSION: The relative risk of all cause in hospital mortality was lower in subjects who underwent biliary decompression in under 11 h compared to greater than 42 h.

7.
J Phys Chem A ; 112(4): 660-8, 2008 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-18181587

RESUMO

Inorganic anions and cations are ubiquitous in environmental chemistry. Here, we use second harmonic generation to track the interaction of the environmentally important metal cations barium, strontium, and cadmium and the nitrate anion with fused quartz/water interfaces at pH 7. Using a dynamic flow system, we assess the extent of reversibility in the binding process and report the absolute number density of adsorbed cations, their charge densities, and their free energies of adsorption. We also present resonantly enhanced second harmonic generation experiments that show that nitrate is surface active and report the free energies and binding constants for the adsorption process. The second harmonic generation spectrum of surface-bound nitrate shows a new adsorption band that cuts further into the solar spectrum than nitrate in the aqueous or solid state. The results that we obtain for all four inorganic ions and the implications for tropospheric and aquatic chemistry as well as geochemistry are discussed in the context of fundamental science as well as pollutant transport models.


Assuntos
Bário/química , Cádmio/química , Nitratos/química , Quartzo/química , Estrôncio/química , Íons , Modelos Químicos , Espectrofotometria Ultravioleta/métodos , Fatores de Tempo , Água/química
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