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1.
J Eur Acad Dermatol Venereol ; 25(9): 1054-60, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21108671

RESUMEN

BACKGROUND: Acne vulgaris is a common skin disease with a large quality of life impact, characterized by comedones, inflammatory lesions, secondary dyspigmentation and scarring. There are few large objective studies comparing acne epidemiology between racial and ethnic groups. OBJECTIVE: This study aimed to define the prevalence and subtypes of acne in women of different racial groups from four ethnicities. METHODS: The sample consisted of 2895 (384 African American, 520 Asian, 1295 Caucasian, 258 Hispanic and 438 Continental Indian) women ranging in age from 10 to 70 years. Photographs of subjects were graded for acne lesions, scars, dyspigmentation, and measurements taken of sebum excretion and pore size. RESULTS: Clinical acne was more prevalent in African American and Hispanic women (37%, 32% respectively) than in Continental Indian, Caucasian and Asian (23%, 24%, 30% respectively) women. All racial groups displayed equal prevalence of both subtypes of acne with the exception of Asians, for whom inflammatory acne was more prevalent than comedonal (20% vs. 10%) acne, and in Caucasians, for whom comedonal acne was more prevalent than inflammatory (14% vs. 10%) acne. Hyperpigmentation was more prevalent in African American and Hispanic (65%, 48% respectively) than in Asian, Continental Indian and Caucasian (18%, 10%, 25% respectively) women. Dyspigmentation and atrophic scarring were more common in African American and Hispanic women than in all other ethnicities. There was a negative correlation between pore size and skin lightness for all ethnicities. Sebum production was positively correlated with acne severity in African American, Asian and Hispanic women, and pore size was positively correlated with acne in African American, Asian and Continental Indian women, (for all above results, P<0.05). LIMITATIONS: Only female participants were recruited. Data collection was restricted to four cities, with some ethnicities from single cities. Acne was evaluated only on the left side of the face and the two-dimensional nature of photography may not capture all skin surface changes. CONCLUSION: Acne prevalence and sequelae were more common in those with darker skin types, suggesting that acne is a more heterogeneous condition than previously described and highlight the importance of skin-colour tailored treatment.


Asunto(s)
Acné Vulgar/epidemiología , Grupos de Población , Acné Vulgar/etnología , Adolescente , Adulto , Anciano , Niño , Femenino , Humanos , Persona de Mediana Edad , Prevalencia , Adulto Joven
2.
Br J Surg ; 97(3): 428-33, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20101674

RESUMEN

BACKGROUND: Electrosurgery for dissection and haemostasis should be associated with minimal thermal spread to surrounding tissues. This study investigated lateral thermal spread following ex vivo application of four commonly utilized instruments. METHODS: Monopolar and bipolar diathermy (power settings 20, 30 and 40 W), the Harmonic Scalpel and Ligasure (power settings 1, 3 and 5) were studied after application to standardized porcine muscle cuts for 5, 10 or 15 s. Temperatures generated at the tips of the instruments, in the tissues adjacent to the tips and 1 cm away were recorded. RESULTS: Following a 5-s application at the highest power setting, the highest mean(s.d.) temperatures recorded at the tips of monopolar and bipolar diathermy, Harmonic Scalpel and Ligasure instruments were 78.9(4.1), 41.9(2.2), 47.6(2.5) and 44.2(2.6) degrees C respectively. Temperatures at the instrument tips after use for 15 s remained above 42 degrees C for 55, 25, 15 and 15 s respectively. Applying monopolar diathermy (10 s at 40 W) resulted in a temperature recording of 59.2(2.2) degrees C in tissues 1 cm away from the tip of the instrument. CONCLUSION: The degree of lateral thermal spread varied with instrument type, power setting and application time. Monopolar diathermy resulted in the highest temperatures and the greatest degree of thermal spread in tissues.


Asunto(s)
Diatermia/instrumentación , Electrocirugia/instrumentación , Instrumentos Quirúrgicos/normas , Animales , Hemostasis Quirúrgica , Porcinos , Temperatura , Conductividad Térmica
3.
Mech Dev ; 124(9-10): 762-74, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17709232

RESUMEN

There are two waves of erythropoiesis, known as primitive and definitive waves in mammals and lower vertebrates including zebrafish. The founding member of the Kruppel-like factor (KLF) family of CACCC-box binding proteins, EKLF/Klf1, is essential for definitive erythropoiesis in mammals but only plays a minor role in primitive erythropoiesis. Morpholino knockdown experiments have shown a role for zebrafish klf4 in primitive erythropoiesis and hatching gland formation. In order to generate a global understanding of how klf4 might influence gene expression and differentiation, we have performed expression profiling of klf4 morphants, and then performed validation of many putative target genes by qRT-PCR and whole mount in situ hybridization. We found a critical role for klf4 in embryonic globin, heme synthesis and hatching gland gene expression. In contrast, there was an increase in expression of definitive hematopoietic specific genes such as larval globin genes, runx1 and c-myb from 24 hpf, suggesting a selective role for klf4 in primitive rather than definitive erythropoiesis. In addition, we show klf4 preferentially binds CACCC box elements in the primitive zebrafish beta-like globin gene promoters. These results have global implications for primitive erythroid gene regulation by KLF-CACCC box interactions.


Asunto(s)
Eritropoyesis/fisiología , Factores de Transcripción de Tipo Kruppel/fisiología , Proteínas de Pez Cebra/fisiología , Pez Cebra/embriología , Animales , Perfilación de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica/fisiología , Globinas/biosíntesis , Globinas/genética , Hemo/biosíntesis , Factores de Transcripción de Tipo Kruppel/sangre , Pez Cebra/fisiología , Proteínas de Pez Cebra/sangre
4.
Curr Biol ; 11(18): 1456-61, 2001 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-11566106

RESUMEN

The specification of the erythroid lineage from hematopoietic stem cells requires the expression and activity of lineage-specific transcription factors. One transcription factor family that has several members involved in hematopoiesis is the Krüppel-like factor (KLF) family [1]. For example, erythroid KLF (EKLF) regulates beta-globin expression during erythroid differentiation [2-6]. KLFs share a highly conserved zinc finger-based DNA binding domain (DBD) that mediates binding to CACCC-box and GC-rich sites, both of which are frequently found in the promoters of hematopoietic genes. Here, we identified a novel Xenopus KLF gene, neptune, which is highly expressed in the ventral blood island (VBI), cranial ganglia, and hatching and cement glands. neptune expression is induced in response to components of the BMP-4 signaling pathway in injected animal cap explants. Similar to its family member, EKLF, Neptune can bind CACCC-box and GC-rich DNA elements. We show that Neptune cooperates with the hematopoietic transcription factor XGATA-1 to enhance globin induction in animal cap explants. A fusion protein comprised of Neptune's DBD and the Drosophila engrailed repressor domain suppresses the induction of globin in ventral marginal zones and in animal caps. These studies demonstrate that Neptune is a positive regulator of primitive erythropoiesis in Xenopus.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Eritropoyesis/fisiología , Proteínas Represoras , Factores de Transcripción/metabolismo , Proteínas de Xenopus , Secuencia de Aminoácidos , Animales , Sitios de Unión , Proteína Morfogenética Ósea 4 , Proteínas Morfogenéticas Óseas/metabolismo , Proteínas de Unión al ADN/genética , Factores de Unión al ADN Específico de las Células Eritroides , Expresión Génica , Hematopoyesis , Factores de Transcripción de Tipo Kruppel , Ratones , Datos de Secuencia Molecular , Homología de Secuencia de Aminoácido , Transducción de Señal , Factores de Transcripción/genética , Xenopus
5.
Clin Transl Imaging ; 5(4): 323-341, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28804703

RESUMEN

PURPOSE: This review aims to summarise the hybrid modality radioguidance techniques currently in clinical use and development, and to discuss possible future avenues of research. Due to the novelty of these approaches, evidence of their clinical relevance does not yet exist. The purpose of this review is to inform nuclear medicine practitioners of current cutting edge research in radioguided surgery which may enter standard clinical practice within the next 5-10 years. Hybrid imaging is of growing importance to nuclear medicine diagnostics, but it is only with recent advances in technology that hybrid modalities are being investigated for use during radioguided surgery. These modalities aim to overcome some of the difficulties of surgical imaging while maintaining many benefits, or providing entirely new information unavailable to surgeons with traditional radioguidance. METHODS: A literature review was carried out using online reference databases (Scopus, PubMed). Review articles obtained using this technique were citation mined to obtain further references. RESULTS: In total, 2367 papers were returned, with 425 suitable for further assessment. 60 papers directly related to hybrid intraoperative imaging in radioguided surgery are reported on. Of these papers, 25 described the clinical use of hybrid imaging, 22 described the development of new hybrid probes and tracers, and 13 described the development of hybrid technologies for future clinical use. Hybrid gamma-NIR fluorescence was found to be the most common clinical technique, with 35 papers associated with these modalities. Other hybrid combinations include gamma-bright field imaging, gamma-ultrasound imaging, gamma-ß imaging and ß-OCT imaging. The combination of preoperative and intraoperative images is also discussed. CONCLUSION: Hybrid imaging offers new possibilities for assisting clinicians and surgeons in localising the site of uptake in procedures such as in sentinel node detection.

6.
Eur J Pharm Biopharm ; 62(1): 26-31, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16154332

RESUMEN

Human serum albumin (HSA) extracted from pooled blood taken from human donors is used in the production of (99m)Tc-labelled macroaggregated albumin (MAA) for lung perfusion imaging. However, concerns for the safety of blood-derived products due to potential contamination by infective agents (e.g. new variant CJD), make alternative production methods necessary. Recombinant DNA technology is a promising method of albumin production avoiding problems associated with human-derived HSA. This paper presents results comparing MAA prepared from recombinant human albumin (rHA, Recombumin) (rMAA) with in-house produced HSA MAA (hMAA) and commercially available MAA (cMAA). (99m)Tc-MAA was prepared using previously published production methods by heating a mixture of albumin and stannous chloride in acetate buffer (pH 5.4) at 70 degrees C for 20 min. Parameters investigated include aggregate size, radiolabelling efficiency, radiochemical and aggregate stability at 4 degrees C and in vitro (in whole human blood) at 37 degrees C and biodistribution studies. Results showed that rMAA could be produced with similar morphology, labelling efficiency and stability to hMAA and cMAA. Our findings confirm that rHA shows significant potential as a direct replacement for HSA in commercially available MAA.


Asunto(s)
Pulmón/diagnóstico por imagen , Radiofármacos/síntesis química , Agregado de Albúmina Marcado con Tecnecio Tc 99m/síntesis química , Albúminas/química , Animales , Estabilidad de Medicamentos , Femenino , Humanos , Tamaño de la Partícula , Conejos , Cintigrafía , Radiofármacos/farmacocinética , Proteínas Recombinantes/química , Agregado de Albúmina Marcado con Tecnecio Tc 99m/farmacocinética , Distribución Tisular
7.
Cancer Res ; 56(22): 5179-85, 1996 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-8912854

RESUMEN

Thirty-one patients suspected of having ovarian cancer received a single i.v. injection of radiolabeled (100 MBq (111)In) engineered human CTMO1 (hCTMO1) to investigate its potential as an internalizing drug carrier. hCTMO1 is a complementary-determining region-grafted human IgG4 monoclonal antibody recognizing an ovarian carcinoma-associated antigen, the MUC-1-gene product. The amount of radioactivity was determined in tumor tissue, various normal tissues, including liver biopsies, and blood samples obtained at laparotomy, 6 days after injection of either 0.1 or 1.0 mg hCTMO1/kg of body weight. Circulating antigen-15-3 was measurable in all patients before injection, and immune complex formation was already present at the end of infusion. In the 0.1 mg/kg group, most of the radioactivity was bound to immune complexes, whereas in the 1.0 mg/kg group, most was bound to IgG monomers. Increasing the hCTMO1 dose 10-fold did not influence the overall disappearance of (111)In from the blood, but the elimination half-life of (111)indium bound to immune complexes was increased 2-fold. Uptake in tumor tissue 6 days postinjection at the 0.1 mg/kg dose was 7.6 times higher (P = 0.0009) than in normal tissue and 2.5 times higher (P = 0.03) than in blood. At the 1.0 mg/kg dose, the uptake in tumor tissue was 14.0 times higher (P = 0.0003) than in normal tissue and 8.1 times higher (P = 0.0007) than in blood. Liver activity was substantial (23.7 +/- 10.5 and 18.3 +/- 6.7% of the injected dose/kg for the 0.1 and 1.0 mg/kg dose group, respectively). These results are superior to those found with other clinically tested anti-MUC-1 gene product antibodies. hCTMO1 seems to be a suitable carrier for cytotoxic agents in ovarian carcinoma patients; the better uptake results and tumor-to-blood ratios are obtained at the higher dose of 1.0 mg hCTMO1/kg body weight.


Asunto(s)
Anticuerpos Monoclonales/farmacocinética , Mucina-1/inmunología , Neoplasias Ováricas/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Semivida , Humanos , Radioisótopos de Indio/farmacocinética , Persona de Mediana Edad , Neoplasias Ováricas/diagnóstico por imagen , Neoplasias Ováricas/inmunología , Cintigrafía , Distribución Tisular
8.
Phys Med ; 32(1): 290-6, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26778578

RESUMEN

The Hybrid Compact Gamma Camera (HCGC) is a small field of view (SFOV) portable hybrid gamma-optical camera intended for small organ imaging at the patient bedside. In this study, a thyroid phantom was used to determine the suitability of the HCGC for clinical thyroid imaging through comparison with large field of view (LFOV) system performance. A direct comparison with LFOV contrast performance showed that the lower sensitivity of the HCGC had a detrimental effect on image quality. Despite this, the contrast of HCGC images exceeded those of the LFOV cameras for some image features particularly when a high-resolution pinhole collimator was used. A clinical simulation showed that thyroid morphology was visible in a 5 min integrated image acquisition with an expected dependency on the activity within the thyroid. The first clinical use of the HCGC for imaging thyroid uptake of (123)I is also presented. Measurements indicate that the HCGC has promising utility in thyroid imaging, particularly as its small size allows it to be brought into closer proximity with a patient. Future development of the energy response of the HCGC is expected to further improve image detectability.


Asunto(s)
Cámaras gamma , Cintigrafía/métodos , Glándula Tiroides/diagnóstico por imagen , Medios de Contraste/química , Diagnóstico por Imagen , Diseño de Equipo , Humanos , Procesamiento de Imagen Asistido por Computador , Radioisótopos de Yodo , Fantasmas de Imagen , Reproducibilidad de los Resultados , Tecnecio/química
9.
J Clin Oncol ; 18(2): 363-70, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10637251

RESUMEN

PURPOSE: More effective intravesical agents are required to limit the recurrence and progression of superficial bladder cancer. This study assessed the ability of copper-67 ((67)Cu)-C595 murine antimucin monoclonal antibody to bind selectively to superficial bladder tumors when administered intravesically, with a view to its development for therapy. PATIENTS AND METHODS: Approximately 20 MBq of (67)Cu-C595 monoclonal antibody was administered intravesically to 16 patients with a clinical indication of superficial bladder cancer. After 1 hour, the bladder was drained and irrigated. Tissue uptake was assessed by imaging and by the assay of tumor and normal tissues obtained by endoscopic resection. RESULTS: Tumor was correctly identified in the images of 12 of 15 patients who were subsequently found to have tumors. Assay of biopsy samples at 2 hours showed a mean tumor uptake of 59.4% of the injected dose per kilogram (SD = 48.0), with a tumor-to-normal tissue ratio of 14.6:1 (SD = 20). After 24 hours (n = 5), this decreased to 4.3% of the injected dose per kilogram (SD = 2.9), with a tumor-to-normal tissue ratio of 1.8:1 (SD = 0.8). CONCLUSION: This study indicates a promising method for the treatment of superficial bladder cancer. Although the mean initial tumor uptake was high, effective therapy of bladder tumors will require an increased retention of the cytotoxic radionuclide in tumor tissue.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Radioisótopos de Cobre/uso terapéutico , Radioinmunoterapia , Neoplasias de la Vejiga Urinaria/radioterapia , Administración Intravesical , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales/farmacocinética , Sitios de Unión de Anticuerpos , Radioisótopos de Cobre/farmacocinética , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Mucina-1/inmunología , Mucina-1/metabolismo , Mucinas/inmunología , Cintigrafía , Neoplasias de la Vejiga Urinaria/diagnóstico por imagen
10.
Phys Med ; 31(1): 98-103, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25440940

RESUMEN

Existing protocols for assessing the performance characteristics of large field-of-view (LFOV) gamma cameras can be inappropriate and require modification for use with small field-of-view (SFOV) gamma camera systems. This communication proposes a generic scheme suitable for evaluating the performance characteristics of SFOV gamma cameras, based on modifications to the standard procedures of NEMA NU1-2007. Key differences in methodology between tests for LFOV and SFOV gamma cameras are highlighted along with the rationale for these changes. It is envisaged that this scheme will provide more appropriate methods for equipment characterisation, ensuring quality and consistency for all SFOV cameras.


Asunto(s)
Cámaras gamma , Diseño de Equipo
11.
Phys Med Biol ; 60(3): 1367-83, 2015 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-25592405

RESUMEN

MRI can assess multiple gastric functions without ionizing radiation. However, time consuming image acquisition and analysis of gastric volume data, plus confounding of gastric emptying measurements by gastric secretions mixed with the test meal have limited its use to research centres. This study presents an MRI acquisition protocol and analysis algorithm suitable for the clinical measurement of gastric volume and secretion volume. Reproducibility of gastric volume measurements was assessed using data from 10 healthy volunteers following a liquid test meal with rapid MRI acquisition within one breath-hold and semi-automated analysis. Dilution of the ingested meal with gastric secretion was estimated using a respiratory-triggered T1 mapping protocol. Accuracy of the secretion volume measurements was assessed using data from 24 healthy volunteers following a mixed (liquid/solid) test meal with MRI meal volumes compared to data acquired using gamma scintigraphy (GS) on the same subjects studied on a separate study day. The mean ± SD coefficient of variance between 3 observers for both total gastric contents (including meal, secretions and air) and just the gastric contents (meal and secretion only) was 3 ± 2% at large gastric volumes (>200 ml). Mean ± SD secretion volumes post meal ingestion were 64 ± 51 ml and 110 ± 40 ml at 15 and 75 min, respectively. Comparison with GS meal volumes, showed that MRI meal only volume (after correction for secretion volume) were similar to GS, with a linear regression gradient ± std err of 1.06 ± 0.10 and intercept -11 ± 24 ml. In conclusion, (i) rapid volume acquisition and respiratory triggered T1 mapping removed the requirement to image during prolonged breath-holds (ii) semi-automatic analysis greatly reduced the time required to derive measurements and (iii) correction for secretion volumes provided accurate assessment of gastric meal volumes and emptying. Together these features provide the scientific basis of a protocol which would be suitable in clinical practice.


Asunto(s)
Vaciamiento Gástrico , Imagen por Resonancia Magnética/métodos , Estómago/patología , Adulto , Algoritmos , Automatización , Calibración , Ingestión de Alimentos , Femenino , Mucosa Gástrica/metabolismo , Voluntarios Sanos , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Variaciones Dependientes del Observador , Periodo Posprandial , Cintigrafía , Reproducibilidad de los Resultados , Adulto Joven
12.
J Bone Miner Res ; 7(3): 295-301, 1992 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1316715

RESUMEN

The bisphosphonate space (BPS) is a quantitative measurement of skeletal uptake of 99mTc-HMDP. We measured BPS in 36 patients with Paget's disease of bone, both before and 6 months after treatment with intravenous APD (disodium pamidronate) infusions. BPS fell after treatment, but proportionally less than serum alkaline phosphatase (ALP) and fasting urinary hydroxyproline/creatinine (HYPRO). There was no dose-response relationship between the dose of APD given and the percentage reduction in ALP and HYPRO at 6 months. Log dose of APD/pretreatment BPS, however, predicted the percentage reduction in ALP and HYPRO very well, and from the respective regression equations it was possible to predict the dose of APD needed to achieve normal values of ALP and HYPRO. In the 10 patients who achieved a normal ALP and 9 patients a normal HYPRO after more than 6 months treatment with APD (range 7-18 months), the predicted dose of APD agreed closely with the actual dose. In conclusion, our data support the idea that log dose APD/pretreatment BPS is a valid predictor of biochemical response in Paget's disease.


Asunto(s)
Huesos/metabolismo , Difosfonatos/uso terapéutico , Enfermedad de Paget Extramamaria/tratamiento farmacológico , Medronato de Tecnecio Tc 99m/metabolismo , Fosfatasa Alcalina/sangre , Creatinina/orina , Humanos , Hidroxiprolina/orina , Infusiones Intravenosas , Enfermedad de Paget Extramamaria/metabolismo , Pamidronato , Análisis de Regresión
13.
Gene ; 242(1-2): 337-45, 2000 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-10721728

RESUMEN

Ermap (erythroid membrane-associated protein), a gene coding for a novel transmembrane protein produced exclusively in erythroid cells, is described. It is mapped to murine Chromosome 4, 57 cM distal to the centromere. The initial cDNA clone was isolated from a day 9 murine embryonic erythroid cell cDNA library. The predicted peptide sequence suggests that ERMAP is a transmembrane protein with two extracellular immunoglobulin folds, as well as a highly conserved B30.2 domain and several phosphorylation consensus sequences in the cytoplasmic region. ERMAP shares a high homology throughout the entire peptide with butyrophilin, a glycoprotein essential for milk lipid droplet formation and release. A GFP-ERMAP fusion protein was localized to the plasma membrane and cytoplasmic vesicles in transiently transfected 293T cells. Northern blot analysis and in-situ hybridization demonstrated that Ermap expression was restricted to fetal and adult erythroid tissues. ERMAP is likely a novel adhesion/receptor molecule specific for erythroid cells.


Asunto(s)
Moléculas de Adhesión Celular/genética , Eritrocitos/metabolismo , Proteínas de la Membrana/genética , Secuencia de Aminoácidos , Animales , Antígenos de Grupos Sanguíneos , Northern Blotting , Butirofilinas , Adhesión Celular , Línea Celular , Núcleo Celular/química , Mapeo Cromosómico , Clonación Molecular , Citoplasma/química , ADN Complementario/química , ADN Complementario/genética , Embrión de Mamíferos/metabolismo , Eritrocitos/citología , Regulación de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica , Proteínas Fluorescentes Verdes , Humanos , Hibridación in Situ , Células K562 , Proteínas Luminiscentes/genética , Proteínas Luminiscentes/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Datos de Secuencia Molecular , Muridae , ARN/genética , ARN/metabolismo , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Alineación de Secuencia , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Distribución Tisular
14.
J Nucl Med ; 26(9): 1011-23, 1985 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-3861794

RESUMEN

Quantitative and qualitative aspects of the blood survival of 131I and 111In-labeled monoclonal antibody 791T/36 have been examined in patients with colo-rectal carcinoma, ovarian carcinoma and osteogenic sarcoma who were receiving labeled antibody in diagnostic immunoscintigraphy trials. The blood clearance of intact antibody radiolabeled with either 131I or 111In was similar. A bi-phasic decline of both radiolabeled preparations was measured with initial half-lives 0.62 and 0.42 days for 131I and 111In labels and then with 1.85 and 1.40 day half-lives, respectively. The Fab fragment of the antibody was lost more rapidly (initial half-life 0.20 days and then 0.78 days). Blood-borne radioactivity was associated predominantly with plasma rather than cellular elements. Radioactivity was still attached to undegraded, uncomplexed, and immunologically active antibody as demonstrated by molecular filtration, immune precipitation, and antigen binding assays. However, anti-mouse-IgG antibody detected within 7 days of administration of radiolabeled antibody was present for at least 10 mo and has implications for the efficiency of repeated image studies.


Asunto(s)
Anticuerpos Monoclonales , Inmunoglobulina G/análisis , Neoplasias/diagnóstico , Animales , Anticuerpos Monoclonales/análisis , Complejo Antígeno-Anticuerpo/análisis , Unión Competitiva , Cromatografía en Gel , Neoplasias del Colon/sangre , Neoplasias del Colon/diagnóstico , Neoplasias del Colon/diagnóstico por imagen , Femenino , Humanos , Fragmentos Fab de Inmunoglobulinas/análisis , Indio , Radioisótopos de Yodo , Marcaje Isotópico , Ratones , Neoplasias/sangre , Neoplasias/diagnóstico por imagen , Osteosarcoma/sangre , Osteosarcoma/diagnóstico , Osteosarcoma/diagnóstico por imagen , Neoplasias Ováricas/sangre , Neoplasias Ováricas/diagnóstico , Neoplasias Ováricas/diagnóstico por imagen , Radioisótopos , Cintigrafía , Neoplasias del Recto/sangre , Neoplasias del Recto/diagnóstico , Neoplasias del Recto/diagnóstico por imagen
15.
J Nucl Med ; 42(5): 726-32, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11337567

RESUMEN

UNLABELLED: Bladder cancer was responsible for >12,000 deaths in the United States in 1999. The high-molecular-weight glycoprotein MUC1 mucin is overexpressed on bladder tumors and represents a useful target for radioimmunoscintigraphy and radioimmunotherapy. We report on the production and initial tracer studies of a 188Re-antibody complex directed against this target and intended for intravesical radioimmunotherapy of superficial bladder cancer. METHODS: 188Re perrhenate was eluted from a 188W/188Re generator. C595 antibody was reduced with 2-mercaptoethanol and was labeled in the presence of stannous tartrate. The final reaction mixture contained high-molecular-weight contamination, which was removed from the complex using an affinity separation technique. The specificity and integrity of the antibody complex were tested by radioimmunoassay and size exclusion chromatography. Tumor localization was investigated using an ex vivo model in human cystectomy specimens. Tracer amounts of the complex were also administered intravesically to three patients with bladder cancer, who were then imaged by gamma scintigraphy. RESULTS: The complex was immunoreactive (70% +/- 17%) and specific for MUC1 antigens. A peak corresponding to a protein of 150 kDa was observed on size exclusion chromatography, showing that the complex was homogeneous. Binding to bladder tumors was observed in an ex vivo model in which tumors were successfully imaged in four specimens. The mean tumor-to-normal tissue ratio in ex vivo bladders was 7:1. Tumor uptake after intravesical administration was confirmed in three patients with bladder cancer (mean tumor-to-normal tissue ratio, 4:1). CONCLUSION: The C595 antibody was labeled with 188Re, providing a radioimmunoconjugate with high immunoreactivity and specificity. Its ability to localize in tumors both in an ex vivo model and after intravesical administration to patients has been shown. This approach will now be extended for the therapy of superficial bladder cancer.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Carcinoma de Células Transicionales/radioterapia , Radioinmunoterapia , Radioisótopos/uso terapéutico , Renio/uso terapéutico , Neoplasias de la Vejiga Urinaria/radioterapia , Anticuerpos Monoclonales/química , Especificidad de Anticuerpos , Cromatografía en Gel , Estabilidad de Medicamentos , Humanos , Técnicas In Vitro , Marcaje Isotópico , Mucina-1/análisis , Radioisótopos/química , Cintigrafía , Renio/química , Vejiga Urinaria/diagnóstico por imagen
16.
Aliment Pharmacol Ther ; 14(2): 155-61, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10651655

RESUMEN

BACKGROUND: Active distal ulcerative colitis is often resistant to topically acting oral formulations. We speculated that the left side of the colon is underexposed to orally-dosed topical agents in patients with active distal colitis. METHODS: Twenty-two healthy volunteers (12 males, aged 22-47 years), and 10 patients (6 males, aged 33-73 years) with active left-sided ulcerative colitis ingested a Eudragit-coated gelatine capsule containing 111In-labelled amberlite resin on four successive days. Regional colonic distribution, transit times and percentage of daily dose resident were calculated from the average of four serial gamma camera images on the 4th day. RESULTS: (mean [95% CI]). When compared to controls, patients with colitis had significantly faster total colon transit (24.3 h [9.5-39.1] vs. 51.7 h [41.1-62.3]) as well as faster proximal colon transit (18.7 h [9.1-28.3] vs. 36.7 [28.5-44.9]), and distal colon transit (3.1 h [-0.5 to 6.8] vs. 15.0 h [10.5-19.5]), respectively (all P < 0.01). Material was asymmetrically distributed in health (proximal colon 69% [63-76] vs. distal colon 31% [24-37]). This asymmetry was more extreme in colitis, with corresponding values of 91% [85-96] vs. 9% [4-15]. As a result colitics had less material in the left-sided colon (9% [4-15] vs. 31% [24-37]), P < 0. 001. Colitics had a significantly lower percentage of the daily dose resident within the left side of the colon compared to controls (13% [-2 to 28] vs. 63% [44-81]), P < 0.01. CONCLUSIONS: Delayed release oral formulation is asymmetrically distributed within the colon in health. This asymmetry is exaggerated in active left-sided ulcerative colitis and, together with faster colonic transit, results in reduced exposure of the distal colon to orally-dosed topical agents.


Asunto(s)
Colitis Ulcerosa/tratamiento farmacológico , Colon/metabolismo , Preparaciones de Acción Retardada/farmacocinética , Resinas Sintéticas/farmacocinética , Administración Oral , Adulto , Anciano , Cápsulas/farmacocinética , Colitis Ulcerosa/patología , Femenino , Tránsito Gastrointestinal , Humanos , Masculino , Persona de Mediana Edad , Ácidos Polimetacrílicos/farmacocinética , Cintigrafía , Factores de Tiempo
17.
Aliment Pharmacol Ther ; 8(5): 489-94, 1994 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7865640

RESUMEN

BACKGROUND: Local delivery of therapeutic agents to the stomach may be a useful strategy in the treatment of Helicobacter pylori infection. We aimed to see whether the intragastric distribution and gastric retention of a therapeutic agent could be improved, either by giving omeprazole or by dosing after a meal. METHODS: Twelve healthy volunteers took part in this double-blind placebo-controlled crossover study comparing the effects of omeprazole 20 mg twice daily for 5 days with placebo, and the fasted with the fed state, on the gastric emptying and intragastric distribution of a soluble scintigrapic marker contained in a drug capsule. RESULTS: Dosing after food profoundly prolonged gastric residence of the drug label, prolonging mean time to 50% emptying (T50) from 0.5 +/- 0.1 h in the fasted state to 2.0 +/- 0.2 h when given after food. Food also improved intragastric distribution by increasing delivery to the body and fundus. Omeprazole enhanced the effect of food, prolonging T50 to 2.9 +/- 0.3 h, but had no effect in fasted subjects. CONCLUSIONS: Dosing after food markedly improves the aspects of local drug delivery to the stomach investigated in this study, and omeprazole enhances this effect. Post-prandial dosing may, therefore, be useful for improving delivery of some anti-Helicobacter agents.


Asunto(s)
Antibacterianos/farmacocinética , Ingestión de Alimentos/fisiología , Vaciamiento Gástrico/efectos de los fármacos , Vaciamiento Gástrico/fisiología , Mucosa Gástrica/metabolismo , Omeprazol/farmacología , Estómago/diagnóstico por imagen , Adulto , Amoxicilina/administración & dosificación , Amoxicilina/farmacocinética , Antibacterianos/administración & dosificación , Cápsulas , Estudios Cruzados , Proteínas en la Dieta/administración & dosificación , Método Doble Ciego , Portadores de Fármacos , Femenino , Alimentos , Humanos , Concentración de Iones de Hidrógeno , Radioisótopos de Indio , Masculino , Ácido Pentético/farmacocinética , Inhibidores de la Bomba de Protones , Cintigrafía , Estómago/efectos de los fármacos , Tecnecio
18.
Aliment Pharmacol Ther ; 15(1): 115-21, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11136284

RESUMEN

BACKGROUND: Risedronate sodium is a pyridinyl bisphosphonate, proven effective for the treatment and prevention of postmenopausal osteoporosis and glucocorticoid-induced osteoporosis and Paget's disease of the bone. AIM: To compare the oesophageal transit, disintegration and gastric emptying of the commercial film-coated risedronate tablet in subjects with gastro-oesophageal reflux disease (GERD) and normal control subjects. METHODS: A total of 30 subjects, 15 patients with GERD and 15 age- and sex-matched, normal control subjects, participated in a single-centre, open-label, comparative gamma scintigraphy study. The GERD subjects had active erosive oesophagitis within 4 weeks prior to dosing. RESULTS: The mean oesophageal transit (GERD, 4.4 s; controls, 3.1 s), mean disintegration (GERD, 21.8 min; controls, 19.2 min) and mean gastric emptying (GERD, 15.9 min; controls, 15.0 min) were similar in the two subject groups. The oesophageal transit is rapid and given the rapid disintegration and gastric emptying, oesophageal contact occurring via reflux of risedronate was unlikely since most, if not all, of the dosage form exited from the stomach within 30 min. CONCLUSIONS: The oval shape and film-coating on the commercial risedronate tablet promotes rapid oesophageal transit and minimizes oesophageal contact, even in the high-risk GERD population.


Asunto(s)
Esófago/metabolismo , Ácido Etidrónico/análogos & derivados , Reflujo Gastroesofágico/metabolismo , Anciano , Anciano de 80 o más Años , Ácido Etidrónico/administración & dosificación , Ácido Etidrónico/farmacocinética , Femenino , Vaciamiento Gástrico , Humanos , Masculino , Persona de Mediana Edad , Ácido Risedrónico
19.
Aliment Pharmacol Ther ; 18(10): 1039-48, 2003 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-14616171

RESUMEN

BACKGROUND: Although 5-HT3 antagonists have been used to treat chemotherapy-induced emesis and diarrhoea-predominant irritable bowel syndrome, the effects of 5-HT3 agonists in humans are unknown. AIM: To determine the effect of MKC-733, a selective 5-HT3 receptor agonist, on upper gastrointestinal motility. METHODS: Oral MKC-733 (0.2, 1 and 4 mg) was compared with placebo in three randomized, double-blind, cross-over studies in healthy males. Antroduodenal manometry was recorded for 8 h during fasting and 3 h post-prandially (n = 12). Gastric emptying and small intestinal transit were determined by gamma-scintigraphy (n = 16). Gastric emptying, accommodation and antral motility were determined by echoplanar magnetic resonance imaging (n = 12). RESULTS: MKC-733 (4 mg) increased the number of migrating motor complexes recorded in the antrum and duodenum (P < 0.001), but had no effect on post-prandial motility. MKC-733 delayed scintigraphically assessed liquid gastric emptying (P = 0.005) and accelerated small intestinal transit (P = 0.038). Echoplanar magnetic resonance imaging confirmed the delayed gastric emptying (P < 0.001) and demonstrated a significant increase in cross-sectional area of the proximal stomach (P < 0.01). CONCLUSIONS: MKC-733 delays liquid gastric emptying in association with relaxation of the proximal stomach, stimulates fasting antroduodenal migrating motor complex activity and accelerates small intestinal transit.


Asunto(s)
Motilidad Gastrointestinal/efectos de los fármacos , Agonistas del Receptor de Serotonina 5-HT3 , Agonistas de Receptores de Serotonina/farmacología , Adolescente , Adulto , Índice de Masa Corporal , Estudios Cruzados , Método Doble Ciego , Cámaras gamma , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Manometría , Persona de Mediana Edad , Piridinas/farmacología , Quinuclidinas/farmacología , Cintigrafía , Estómago/diagnóstico por imagen
20.
Leuk Lymphoma ; 4(5-6): 363-9, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-27467669

RESUMEN

It is claimed that late relapses of Hodgkin's disease have a good prognosis when retreated. A number of unfavourable outcomes led us to review our experience of 72 consecutive cases of Hodgkin's disease diagnosed and treated in a combined clinical haematology and radiation oncology unit between 1968 and 1984. 62 of 72 patients (86%) achieved a complete remission and of these, 35 patients (56%) relapsed, 18 occurring more than three years after diagnosis. Thus, 4 patient groups were identified: 10 patients with refractory disease, 27 patients who went into complete remission and have not relapsed, 17 patients who relapsed within 3 years of diagnosis (early relapse) and 18 patients who relapsed more than 3 years from diagnosis (late relapse). Patients who relapsed were retreated with well accepted protocols of chemotherapy and/or radiotherapy with surprisingly poor results. There was no significant difference between the survival from relapse of patients who relapsed early compared to those who relapsed late. Late relapses are not uncommon in Hodgkin's disease and the prognosis may be less favourable than generally perceived. The risk of relapse was almost constant with time and brings into question the concept of early and late relapse.

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