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1.
Langmuir ; 40(1): 52-61, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38113451

RESUMEN

In this study, we present an in-depth characterization of a diamond-like carbon (DLC) film, using a range of techniques to understand the structure and chemistry of the film both in the interior and particularly at the DLC/air surface and DLC/liquid interface. The DLC film is found to be a combination of sp2 and sp3 carbon, with significant oxygen present at the surface. The oxygen seems to be present as OH groups, making the DLC somewhat hydrophilic. Quartz-Crystal Microbalance (QCM) isotherms and complementary neutron reflectivity data indicate significant adsorption of a model additive, bis(2-ethylhexyl) sulfosuccinate sodium salt (AOT) surfactant, onto the DLC from water solutions and indicate the adsorbed film is a bilayer. This initial study of the structure and composition of a model surfactant is intended to give a clearer insight into how DLC and additives function as antiwear systems.

2.
J Clin Invest ; 59(2): 217-25, 1977 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-64472

RESUMEN

Cell populations obtained by bronchial lavage from human subjects were examined for the presence of cells related to the mast cell-basophil series. Such bronchial lumen histamine-containing cells (BLHCC) were identified. The BLHCC stained with toluidine blue may be identified by bright field or dark field microscopy. The BLHCC are alive as evidenced by ability to release histamine (H) after exposure to anti-IgE or calcium ionophore. Although H release from peripheral blood leukocytes by these two agents is potentiated by the presence of D2O, H release from BLHCC of the same subjects by anti-IgE or calcium ionophore was not potentiated by D2O. In studies comparing bronchial cell populations of humans and rhesus monkeys with peripheral blood leukocyte populations of the same subjects, the histamine content of the bronchial cell population was much higher in rhesus monkeys. IgE/Alb ratios of respiratory secretions and serum of the same human subjects were of the same order of magnitude in contrast to previous comparisons done on these fluids in rhesus monkeys.


Asunto(s)
Bronquios/citología , Histamina , Animales , Bronquios/análisis , Bronquios/inmunología , Deuterio , Haplorrinos , Histamina/análisis , Liberación de Histamina/efectos de los fármacos , Humanos , Sueros Inmunes , Inmunoglobulina E/análisis , Leucocitos/metabolismo , Macaca mulatta , Masculino
3.
Clin Oncol (R Coll Radiol) ; 27(9): 519-26, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26093507

RESUMEN

AIMS: To analyse our 5 and 10 year prostate brachytherapy outcome data and to assess the impact of PSA nadir on relapse free survival and whether an alternative definition of PSA relapse could detect men destined to fail by the Phoenix definition at an earlier time point. MATERIALS AND METHODS: 474 men were treated over a 10 year period between 20012 and 2011 and divided into 2 five year cohorts for the purpose of the analysis. RESULTS: The risk of relapse is strongly predicted by post treat prostate-specific antigen (PSA) nadir. After 3 years post-treatment, PSA nadir plus 0.4 ng/ml identified men at risk of relapse 17 months earlier than the Phoenix definition. CONCLUSION: The Phoenix definition of nadir plus 2.0 ng/ml does not allow the early identification of men destined to relapse. The initiation of salavage therapy at the earliest opportunity could potentially affect subsequent survival and an outline randomised controlled trial proposal is presented.


Asunto(s)
Braquiterapia/métodos , Radioisótopos de Yodo/administración & dosificación , Recurrencia Local de Neoplasia/sangre , Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/sangre , Neoplasias de la Próstata/radioterapia , Adulto , Anciano , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico
4.
J Clin Endocrinol Metab ; 84(11): 4209-13, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10566674

RESUMEN

Neuroendocrine tumors of the cervix are rare and are often under- or misdiagnosed. Because these tumors are very aggressive, early diagnosis and subsequent treatment are warranted. We describe a 46-yr-old woman with carcinoid syndrome caused by an atypical carcinoid of the uterine cervix. At age 44, she had dysplasia on Pap smear and underwent total abdominal hysterectomy with the diagnosis of adenocarcinoma. Fourteen months postoperatively, she developed the carcinoid syndrome and was found to have numerous liver metastases. Histological and immunohistochemical investigations of biopsy specimens from the patient's liver lesions and original cervical lesion ("adenocarcinoma") suggested that this woman had a primary atypical carcinoid of the uterine cervix with metastases to the liver. Treatment with octreotide and alkylating agents decreased the episodes of flushing and diarrhea within 8 weeks. If an adenocarcinoma of the uterine cervix is diagnosed, atypical carcinoid should be in the differential diagnosis. Symptoms of the carcinoid syndrome should be pursued and, if present, a urinary 5-hydroxyindolacetic acid level should be obtained. Timely diagnosis of a neuroendocrine tumor of the cervix may improve survival.


Asunto(s)
Tumor Carcinoide/diagnóstico , Neoplasias del Cuello Uterino/diagnóstico , Adenocarcinoma , Antineoplásicos Hormonales/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Tumor Carcinoide/secundario , Tumor Carcinoide/terapia , Diagnóstico Diferencial , Femenino , Humanos , Inmunohistoquímica , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/secundario , Imagen por Resonancia Magnética , Persona de Mediana Edad , Octreótido/administración & dosificación , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/secundario , Prueba de Papanicolaou , Síndrome , Neoplasias del Cuello Uterino/terapia , Frotis Vaginal
5.
Radiother Oncol ; 51(3): 281-90, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10435823

RESUMEN

BACKGROUND AND PURPOSE: A hierarchy of dosimetry, planning and machine performance checks and evaluations of clinical outcomes have been widely used in radiotherapy for decades. Procedures, codes of practice and guidance are readily available on the 'technical aspects' of radiotherapy treatments, maintenance of which is achieved by quality control checks within a quality assurance approach to radiotherapy. Recently a series of high profile, well-publicised treatment 'accidents' resulting in damage to patients have focused the attention of both professionals and the public. There is now pressure to introduce formal quality management systems. Patients and their relatives/carers are having their expectations raised but their definition of a quality service differs from that generally considered by the oncology professionals. Most departmental managers and staff have wide experience of quality control checks. They understand the philosophy of quality assurance. However the idea of formal quality systems/quality management is alien to them. What is a professional/departmental manager to do? MATERIALS AND METHODS: This paper addresses that question by discussing the underlying principles of quality management covering service provision as well as technical radiotherapy treatment delivery and by providing some guidance based on experience in the practical implementation of quality management through three stages of development: a QA programme incorporating checks on essential parts of the technical treatment delivery, a formal documented certified QA system focusing on technical treatment delivery, a comprehensive quality management system covering all parts of a service. RESULTS AND CONCLUSIONS: One possible action plan is provided indicating progress through the three stages of development based on experience in one large Radiation Oncology Department. With planning, resources and commitment, a comprehensive quality of service management system is achievable in radiotherapy.


Asunto(s)
Garantía de la Calidad de Atención de Salud/métodos , Radioterapia/normas , Educación Profesional , Humanos , Administración de Personal , Traumatismos por Radiación/prevención & control , Liberación de Radiactividad Peligrosa/prevención & control , Radiología/educación , Radiometría , Gestión de la Calidad Total
6.
Chest ; 83(4): 696-8, 1983 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-6831960

RESUMEN

We present a case of azathioprine-associated alveolitis diagnosed by gallium-67 scanning and transbronchial biopsy. The patient denied respiratory symptoms, exhibited spiking fevers, and had normal chest roentgenograms. Allopurinol inhibition of azathioprine metabolism may have been a contributing factor.


Asunto(s)
Azatioprina/efectos adversos , Enfermedades Pulmonares/inducido químicamente , Alveolos Pulmonares/efectos de los fármacos , Adulto , Alopurinol/farmacología , Alopurinol/uso terapéutico , Azatioprina/antagonistas & inhibidores , Enfermedad de Crohn/tratamiento farmacológico , Humanos , Inflamación/inducido químicamente , Cálculos Renales/prevención & control , Masculino
7.
Surgery ; 126(6): 1105-10, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10598194

RESUMEN

BACKGROUND: Gastrointestinal foregut carcinoids make up a small percentage (3% to 6%) of all reported carcinoids. Because these tumors are so uncommon, comparisons between the subtypes have been difficult. The goal of this study was to compare the hormonal and clinical characteristics of gastric, duodenal, and pancreatic carcinoids. METHODS: A prospective database of approximately 750 carcinoid patients seen by one author over 25 years was reviewed, and the 104 patients with gastric (33), duodenal (17), or pancreatic (54) carcinoids were selected as the subgroup for analysis. These patients were compared with regard to hormone levels, clinical course, treatment, and survival. RESULTS: Duodenal carcinoids exhibited significantly lower serotoninergic hormone levels than did the gastric and pancreatic carcinoids (urine 5-hydroxyindoleacetic acid [mg/24 h], 5 +/- 1 vs 16 +/- 5 and 47 +/- 12, respectively, P = .03). Pancreatic carcinoids presented with more advanced stage (distant metastases 87% vs 42% and 20% for gastric and duodenal, respectively) and had worse outcomes than patients with gastric and duodenal tumors with 10-year survivals of 10%, 59%, and 58%, respectively (P = .003). CONCLUSIONS: Pancreatic carcinoids produce higher levels of serotoninergic hormones and have a significantly higher stage and worse outcome than other foregut carcinoids. This study demonstrates that the organ of origin is an important determinant of hormonal activity and clinical course for patients with foregut carcinoids.


Asunto(s)
Tumor Carcinoide/química , Tumor Carcinoide/diagnóstico , Neoplasias Gastrointestinales/química , Neoplasias Gastrointestinales/diagnóstico , Adulto , Distribución por Edad , Anciano , Análisis de Varianza , Tumor Carcinoide/mortalidad , Neoplasias Duodenales/química , Neoplasias Duodenales/diagnóstico , Neoplasias Duodenales/mortalidad , Femenino , Neoplasias Gastrointestinales/mortalidad , Humanos , Ácido Hidroxiindolacético/sangre , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/química , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/mortalidad , Estudios Retrospectivos , Serotonina/sangre , Distribución por Sexo , Neoplasias Gástricas/química , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/mortalidad , Análisis de Supervivencia
8.
J Chromatogr A ; 798(1-2): 73-82, 1998 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-9542128

RESUMEN

Recovery of recombinant proteins from endogenous, host molecules can be an experimentally intensive and time-consuming task. Often the time to analyze material during development of recovery procedures is the rate-limiting step. Nowadays, modern techniques and equipment are being specifically engineered to make this effort much more efficient. We present a case study to illustrate how a new, automation tool, designed for easy, systematic methods development, can be used for very rapid process and analytical optimization. This tool uses robotics to integrate process development with rapid LC-based analysis requiring no user intervention. The methods and procedures described can be generalized to any recombinant protein recovery campaign.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Proteínas Recombinantes/aislamiento & purificación , Escherichia coli/metabolismo , Concentración de Iones de Hidrógeno , Inmunoglobulina G , Robótica , Proteína Estafilocócica A/aislamiento & purificación
9.
Am Surg ; 56(8): 460-2, 1990 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-2375544

RESUMEN

The axillary thoracotomy should be the incision of choice for most uncomplicated general thoracic surgical procedures. It can be performed rapidly, avoids major muscle transection, and by employing a double lumen endotracheal tube will permit segmental resection as well as lobectomy without technical problem. One hundred consecutive, elective axillary thoracotomies were performed with minimal morbidity and only one mortality. Twenty-five of the patients were of high surgical risk. The larger posterolateral thoracotomy is reserved for repeat thoracotomy, Pancoast tumors, difficult procedures such as bronchoplasty and/or radical pneumonectomy, and when pleural symphysis is expected. Sometimes called lateral thoracotomy or mini-thoracotomy, the axillary thoracotomy is our most common incision.


Asunto(s)
Toracotomía , Axila , Humanos
10.
Nanoscale ; 5(1): 239-45, 2013 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-23154433

RESUMEN

We report on a method to enhance the light-emission efficiency of printable thin films of a polymer doped with luminescent (CdSe)ZnS nanocrystals via metallic nanoparticles and nanoimprinted photonic crystals. We experimentally show a strong fluorescence enhancement of nanocrystals by coupling exciton-plasmon with the localized surface plasmon of metallic nanoparticles. The emitted light is efficiently diffracted by photonic crystals structures directly imprinted in the nanocomposite polymer. By combining the field susceptibility technique with optical Bloch equations, we examine the interaction of the quantum and plasmonic entities at small distances.


Asunto(s)
Iluminación/métodos , Nanopartículas del Metal/química , Nanopartículas del Metal/ultraestructura , Impresión Molecular/métodos , Semiconductores , Ensayo de Materiales , Tamaño de la Partícula , Fotones
12.
Rev Sci Instrum ; 81(1): 013906, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20113112

RESUMEN

Two approaches to conducting magneto-optical confocal spectroscopy are described, in each of which the confocal head is rotatable with respect to the magnetic field. A coudé arrangement has been shown to give adequate performance for scanned imaging, but lower optical throughput than a system based on single-mode optical fiber transport. The design criteria for a cryogenic fiber-coupling objective are described, and the tolerances demanded in lens alignment are shown to be relatively benign, allowing manufacture without special techniques. The practical use of the rotating confocal system with commercial stick-slip positioners has been shown to be rigid enough, and asymmetric weight distribution and diamagnetic forces are small enough to permit single quantum emitters to be studied over a range of angles and field strengths.

18.
Eur J Cancer ; 45(5): 795-9, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19101140

RESUMEN

BACKGROUND: Sentinel node biopsy (SNB) in breast cancer conventionally utilises a preoperative radioisotope injection and lymphoscintigraphy, which is time consuming and painful. The aim of this study was to evaluate a potentially more efficient and practical technique of immediate preoperative injection of blue dye and radiopharmaceutical by the surgeon (without involvement of a nuclear medicine department). METHOD: One hundred and sixty three clinically node negative patients with invasive breast cancer undergoing breast-conserving surgery were included. The radiopharmaceutical was delivered to the operating suite and injected by the surgeon in the subareolar region immediately after induction of anaesthesia. Sentinel node biopsy was performed in conjunction with removal of any palpable axillary lymph nodes (axillary node sampling). RESULTS: Sentinel nodes (SNs) were detected in 161 of 163 women. On average, 3.0 sentinel nodes were identified. Twenty nine patients had involved nodes of whom 28 had a positive sentinel node. Of the two patients with failed identification, one had involved axillary lymph nodes on sampling and the other had an involved intramammary lymph node. CONCLUSION: This method produces results identical to those obtained with other techniques. This study shows that sentinel node biopsy can be performed safely without involvement of a nuclear medicine department with the added benefits of no preoperative injection and improved efficiency in the operating suite.


Asunto(s)
Neoplasias de la Mama/patología , Cuidados Preoperatorios/métodos , Biopsia del Ganglio Linfático Centinela/métodos , Adulto , Anciano , Anciano de 80 o más Años , Axila , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/cirugía , Competencia Clínica , Colorantes , Femenino , Humanos , Escisión del Ganglio Linfático , Persona de Mediana Edad , Estudios Prospectivos , Cintigrafía , Radiofármacos , Colorantes de Rosanilina , Sensibilidad y Especificidad , Agregado de Albúmina Marcado con Tecnecio Tc 99m
19.
Am Rev Respir Dis ; 114(6): 1061-7, 1976 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1008342

RESUMEN

Twenty-one healthy, middle-aged volunteers and 8 patients with chronic lung disease were given live, attenuated influenza virus vaccine by nasal spray. Forced vital capacity, 1-sec forced expiratory volume, ratio of 1-sec forced expiratory volume to forced vital capacity, residual volume, ratio of airway conductance to lung volume, maximal expiratory flows after exhalation of 50 and of 75 per cent of the forced vital capacity, closing volume, slope of Phase III, volume of isoflow, single-breath diffusing capacity for CO, and arterial blood gases were measured before and 3, 7, 10, and 21 days after exposure. Vaccination was well tolerated by the healthy volunteers without change in pulmonary function. In contrast, the patients tended to develop increased respiratory symptoms and had a slight decrease in mean forced expiratory volume in 1 sec 3 weeks after vaccination.


Asunto(s)
Vacunas contra la Influenza/efectos adversos , Enfermedades Pulmonares/complicaciones , Administración Intranasal , Adulto , Anciano , Enfermedad Crónica , Femenino , Humanos , Volumen de Reserva Inspiratoria , Enfermedades Pulmonares/fisiopatología , Mediciones del Volumen Pulmonar , Masculino , Persona de Mediana Edad , Volumen Residual , Respiración , Capacidad Pulmonar Total , Vacunas Atenuadas/efectos adversos
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