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1.
Biomed Opt Express ; 13(10): 5171-5186, 2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-36425623

RESUMEN

We demonstrate the training of a generative adversarial network (GAN) for the prediction of optical property maps (scattering and absorption) using spatial frequency domain imaging (SFDI) image data sets that are generated synthetically with a free open-source 3D modelling and rendering software, Blender. The flexibility of Blender is exploited to simulate 5 models with real-life relevance to clinical SFDI of diseased tissue: flat samples containing a single material, flat samples containing 2 materials, flat samples containing 3 materials, flat samples with spheroidal tumours and cylindrical samples with spheroidal tumours. The last case is particularly relevant as it represents wide-field imaging inside a tubular organ e.g. the gastro-intestinal tract. In all 5 scenarios we show the GAN provides an accurate reconstruction of the optical properties from single SFDI images with a mean normalised error ranging from 1.0-1.2% for absorption and 1.1%-1.2% for scattering, resulting in visually improved contrast for tumour spheroid structures. This compares favourably with the ∼10% absorption error and ∼10% scattering error achieved using GANs on experimental SFDI data. Next, we perform a bi-directional cross-validation of our synthetically-trained GAN, retrained with 90% synthetic and 10% experimental data to encourage domain transfer, with a GAN trained fully on experimental data and observe visually accurate results with an error of 6.3%-10.3% for absorption and 6.6%-11.9% for scattering. Our synthetically trained GAN is therefore highly relevant to real experimental samples but provides the significant added benefits of large training datasets, perfect ground-truths and the ability to test realistic imaging geometries, e.g. inside cylinders, for which no conventional single-shot demodulation algorithms exist. In the future, we expect that the application of techniques such as domain adaptation or training on hybrid real-synthetic datasets will create a powerful tool for fast, accurate production of optical property maps for real clinical imaging systems.

2.
J Bone Joint Surg Br ; 88(11): 1492-6, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17075096

RESUMEN

We reviewed the evidence for hip surveillance in children with cerebral palsy from the published literature. Publications were identified using the Cochrane controlled trials register, the MEDLINE, EMBASE and CINAHL databases and by hand searching key journals and their references. Studies were included if they reported the frequency, associated risk factors or surveillance measures undertaken to identify subluxation or dislocation of the hip in children with cerebral palsy. Assessment of the quality of the methodology was undertaken independently by two researchers. Four studies described the natural history, incidence and risk factors for dislocation of the hip. Two reported their surveillance results. Approximately 60% of children who were not walking by five years of age were likely to develop subluxation of the hip, with the greatest risk in those with severe neurological involvement. The introduction of surveillance programmes allowed earlier identification of subluxation and reduced the need for surgery on dislocated hips. Surveillance can identify children most at risk of subluxation using radiological methods which are widely available.


Asunto(s)
Parálisis Cerebral/complicaciones , Luxación de la Cadera/diagnóstico , Adolescente , Parálisis Cerebral/fisiopatología , Niño , Preescolar , Femenino , Luxación de la Cadera/complicaciones , Luxación de la Cadera/cirugía , Humanos , Lactante , Masculino , Cuadriplejía/complicaciones , Proyectos de Investigación , Factores de Riesgo , Caminata/fisiología
3.
Invest New Drugs ; 19(4): 329-33, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11561694

RESUMEN

In a previous phase II trial of the synthetic topoisomerase I inhibitor, 9-aminocamptothecin (9-AC), given as a 72-h infusion, we identified modest single agent activity of 9% in patients with previously untreated advanced non-small cell lung cancer (NSCLC). Preclinical studies suggested that a more prolonged continuous infusion of the drug might lead to greater antitumor activity. A phase I study recommended a phase II dose of 25 microg/m2/hr for 120 h (3000 microg/m2 over 5 days), administered for 2 consecutive weeks of a 3-week cycle. We utilized this schedule and enrolled 13 chemotherapy-naïve patients with Stage IIIB and IV NSCLC in this trial: median age 67 (range 57-74); 46% male; 92% stage IV; and median performance status 1. Twelve patients are available for response and toxicity evaluation after 2 cycles of therapy. One patient achieved a partial response. Four patients had stable disease while seven patients had progressive disease. Patients with stable or progressive disease after two cycles received no additional 9-AC, and were offered conventional chemotherapy. The median survival time was 10.2 months and the one-year survival rate 28% (95% confidence interval, 5-58%). Significant toxicities included myelosuppression, fatigue, and anorexia. One patient had grade 4 neutropenia following the first week of cycle 2, and did not receive additional therapy. There were no neutropenia-related infections. These data suggest that this prolonged schedule is unlikely to increase 9-AC's very modest activity in NSCLC above that seen with the simpler 72-h administration schedule. Further evaluation of 9-AC in NSCLC is not recommended.


Asunto(s)
Antineoplásicos/administración & dosificación , Camptotecina/análogos & derivados , Camptotecina/administración & dosificación , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Anciano , Antineoplásicos/efectos adversos , Camptotecina/efectos adversos , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Femenino , Factor Estimulante de Colonias de Granulocitos/uso terapéutico , Humanos , Infusiones Intravenosas , Neoplasias Pulmonares/mortalidad , Masculino , Persona de Mediana Edad , Tasa de Supervivencia , Factores de Tiempo , Inhibidores de Topoisomerasa I , Resultado del Tratamiento
5.
Clin Lung Cancer ; 2(2): 128-32, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-14731323

RESUMEN

STEALTH cisplatin (SPI-77) is a liposomal formulation of cisplatin that has activity in animal models of non small-cell lung cancer (NSCLC). Vinorelbine has documented clinical activity in NSCLC. The purpose of this study was to determine the dose-limiting toxicity (DLT) and maximum tolerated dose (MTD) of SPI-77 when administered in combination with a fixed dose of vinorelbine to patients with stage IIIB or IV NSCLC refractory to or recurrent following previous chemotherapy. SPI-77 was given on day 1 in combination with vinorelbine at a fixed dose of 25 mg/m2 on days 1 and 8 of a 3-week treatment cycle. Dose escalation of SPI-77 progressed as follows: 20, 40, 80, 100, 120, and 140 mg/m2. Twenty patients were entered (11 men and nine women; median age, 63 years). Sixty-four complete cycles of therapy were administered, and 19 of 20 patients completed at least 1 cycle of combination chemotherapy. Neutropenia was dose limiting at a SPI-77 dose of 140 mg/m2. Neuropathy and nephrotoxicity were minimal and not dose related. A partial response was observed in three of 17 patients eligible for a response evaluation and response duration ranged from 6 weeks to 5 months. In conclusion, treatment with combination SPI-77 and vinorelbine was well tolerated, and our recommended phase II dose is 120 mg/m2 of SPI-77 in combination with vinorelbine at 25 mg/m2. Activity was observed in this patient population, and additional phase II testing of this regimen in a less extensively pretreated cohort of patients with NSCLC is indicated.

6.
Oncology (Williston Park) ; 13(8): 1075-88; discussion 1088, 1091-4, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10499243

RESUMEN

The optimal therapy for locally advanced, unresectable, stage III non-small-cell lung cancer (NSCLC) continues to evolve. The critical determinants of overall survival include local tumor control and the eradication of subclinical micrometastatic disease. Historically, standard radiation therapy resulted in a median survival of 7 to 10 months. In a randomized trial, the Cancer and Leukemia Group B (CALGB) established the superiority of induction cisplatin (Platinol) and vinblastine chemotherapy followed by radiation therapy. Additional studies revealed that induction chemotherapy improved survival rates by decreasing metastatic disease progression. Three independent meta-analyses confirmed the survival benefit afforded by cisplatin-based induction chemotherapy followed by radiotherapy, and helped to establish this as the new standard of care. Other investigators have demonstrated improvements in local tumor control and survival with either concurrent chemoradiotherapy or hyperfractionated radiotherapy. Most recently, attention has focused on radiation dose intensity and the utilization of newer, highly active chemotherapeutic agents with concurrent or sequential radiation therapy. These newer drugs, including paclitaxel (Taxol), docetaxel (Taxotere), gemcitabine (Gemzar), vinorelbine (Navelbine), and irinotecan (Camptosar), enhance radiation cytotoxicity and, when administered in systemically active dosages, may also control micrometastatic disease. Phase I and II studies of novel chemoradiation regimens continue to demonstrate encouraging results, and several large randomized clinical trials are currently enrolling patients.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/radioterapia , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Cisplatino/efectos adversos , Cisplatino/uso terapéutico , Terapia Combinada , Supervivencia sin Enfermedad , Fraccionamiento de la Dosis de Radiación , Femenino , Humanos , Neoplasias Pulmonares/mortalidad , Masculino , Metaanálisis como Asunto , Estadificación de Neoplasias , Pronóstico , Ensayos Clínicos Controlados Aleatorios como Asunto , Análisis de Supervivencia
7.
Arch Dis Child ; 73(4): 345-7, 1995 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7492201

RESUMEN

Between 1979 and 1994, 21 children (nine females, 12 males) with intracranial tumours diagnosed before the age of 2 years (range 2-23 months) were treated at the University Hospital of Wales. The commonest presenting symptoms were vomiting (n = 9) and unsteadiness (n = 8); the commonest presenting sign was enlarged occipitofrontal circumference (> 97th centile in 16 and > 90th centile in a further two). In five cases with signs of raised intracranial pressure, meningitis was the clinical diagnosis, and a lumbar puncture was performed. For cases with long delays in diagnosis, multiple other disorders had been considered and the significance of head enlargement had not been recognised. In very early childhood, intracranial tumours are uncommon and can mimic other disorders, especially meningitis. Early neuroimaging is advised when a child presents with recent onset of neurological symptoms and a disproportionately large head.


Asunto(s)
Neoplasias Encefálicas/diagnóstico , Astrocitoma/diagnóstico , Neoplasias Encefálicas/complicaciones , Neoplasias Encefálicas/patología , Diagnóstico Diferencial , Ependimoma/diagnóstico , Femenino , Humanos , Lactante , Masculino , Meduloblastoma/diagnóstico , Neoplasias Supratentoriales/complicaciones , Neoplasias Supratentoriales/diagnóstico , Factores de Tiempo
8.
Am J Med Sci ; 297(5): 280-4, 1989 May.
Artículo en Inglés | MEDLINE | ID: mdl-2640419

RESUMEN

We examined the effect of intranasal administration of deferoxamine on iron excretion in seven patients with iron overload secondary to chronic transfusion therapy. Deferoxamine was administered in doses of 0.75 to 3.0 gm given over 12 hours in a variety of dosing schedules. There was a probable, though not significant, dose response relationship between the amount of iron excreted and the dose administered. The amount of iron excreted was 10%-15% of that obtained using the same dosage of deferoxamine given by the subcutaneous route over the same time period. Hourly administration was more effective than less frequent administration. Addition of taurodeoxycholate to deferoxamine did not increase its absorption as measured by the levels of iron excretion. Side effects were few and consisted mainly of mild nasal irritation and a bad taste in the mouth. Nasal administration of deferoxamine may be a useful adjunct to iron chelation in patients receiving chronic transfusion therapy, particularly in those who are noncompliant with parenteral means of administration.


Asunto(s)
Deferoxamina/administración & dosificación , Hierro/envenenamiento , Administración Intranasal , Adolescente , Adulto , Niño , Deferoxamina/efectos adversos , Deferoxamina/farmacocinética , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Ferritinas/sangre , Humanos , Inyecciones Subcutáneas , Hierro/orina , Cooperación del Paciente , Ácido Taurodesoxicólico/farmacología
11.
Science ; 151(3715): 1226-8, 1966 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-4286341

RESUMEN

Eleven of twelve human breast cancers contained a lipid which increased urinary (45)Ca and (40)Ca excretion of (45)Ca-labeled, parathyroidectomized rats receiving a low Ca diet. The lipid has mobility on thin-layer chromatography and gas-liquid chromatography close to, but not identical with, that of 7-dehydrocholesterol. Authentic 7-dehydrocholesterol has osteolytic activity similar to that of the extracted sterol. Fluorescence and Lieberman-Burchard reactions of the extracted sterol are similar to those of 7-dehydrocholesterol. The lipid was found by thin-layer chromatography in the extracts which had osteolytic activity. Neither the lipid nor osteolytic activity was found in extracts of tissue from two normal human breasts.


Asunto(s)
Neoplasias de la Mama/metabolismo , Calcio/metabolismo , Esteroles/patogenicidad , Animales , Isótopos de Calcio , Colecalciferol , Cromatografía de Gases , Cromatografía en Capa Delgada/etiología , Descalcificación Patológica/efectos de los fármacos , Femenino , Fluorescencia , Humanos , Técnicas In Vitro , Radiometría , Ratas/farmacología , Orina , Vitamina D
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