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1.
Appl Radiat Isot ; 197: 110812, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37087867

RESUMEN

Some scientific discoveries are well known only to a core group of researchers working on technical subjects. Nevertheless, they open new research directions, allow existing knowledge to be viewed in entirely new and useful ways, or provide a way to make something that was hard or impossible to make before. Carbon-11 methyl triflate ([11C]MeOTf) is one such advance, facilitating the synthesis of many carbon-11 radio tracers and broadening the range of applications of carbon-11 radiochemistry. The year 2022 marked the 30th anniversary of the original paper in Applied Radiation and Isotopes introducing a simple synthesis of [11C]MeOTf from carbon-11 methyl iodide ([11C]MeI) and it also marked the end of the fruitful career and life of the researcher who developed it, Douglas Jewett. It seems fitting to say a few words on how it came to be and how it has helped advance carbon-11 radiochemistry.

2.
Appl Radiat Isot ; 140: 333-341, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30138815

RESUMEN

In the present study, the effect of radiolabeling conditions on radiolabeling efficiency and achievable specific activity of a DOTA-conjugated highly-lipophilic peptide containing three disulfide cyclization bonds was examined. The peptide is designed to bind specifically (with high affinity) to cell-surface receptor guanylyl cyclase C (GCC), which is universally expressed by colorectal cancer cells. The effect of systematic variation of chemical parameters pH, mass of peptide, acetate buffer concentration (ionic strength), and inclusion of ethanol in the radiolabeling reaction vessel on achievable specific activity and labeling efficiency was examined. In addition, a unique approach to acetone-based elution of 68Ga from an initial cation-exchange pre-concentration column is introduced, which improved radiochemical yield and radiochemical purity. For the evaluation of the acetone-based method, two different post-radiolabeling reverse-phase (C18) approaches to purify the final radiolabeled peptide were tested. These results revealed the potential for peptide degradation via the cleavage of disulfide cyclization bonds to form free thiols when using one of these C18 cartridges. The final optimized procedure enabled radiolabeling efficiency of greater than 99% and specific activity greater than 35 MBq/nmole in less than 30 min. The optimized parameters were amenable to the use of an automated 68Ge/68Ga generator and fluid-handling system for clinical production of the GCC receptor-specific [68Ga]DOTA-MLN6907 peptide. The chemical characteristics of individual peptides govern the most appropriate radiolabeling conditions for the preparation of radiopharmaceuticals.


Asunto(s)
Radioisótopos de Galio/química , Compuestos Heterocíclicos con 1 Anillo/química , Péptidos/química , Péptidos/síntesis química , Radiofármacos/química , Radiofármacos/síntesis química , Quelantes/química , Neoplasias Colorrectales/diagnóstico por imagen , Humanos , Péptidos/farmacocinética , Tomografía de Emisión de Positrones , Radioquímica/métodos , Radiofármacos/farmacocinética , Receptores de Enterotoxina/metabolismo
3.
J Nucl Med ; 59(11): 1692-1698, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-29523629

RESUMEN

Pretherapy PET with 86Y-DOTATOC is considered the ideal dosimetry protocol for 90Y-DOTATOC therapy; however, its cost, limited availability, and need for infusion of amino acids to mimic the therapy administration limit its use in the clinical setting. The goal of this study was to develop a dosimetric method for 90Y-DOTATOC using 90Y-DOTATOC PET/CT and bremsstrahlung SPECT/CT and to determine whether dosimetry-based administered activities differ significantly from standard administered activities. Methods: This was a prospective phase 2 trial of 90Y-DOTATOC therapy in patients with somatostatin receptor-positive tumors. 90Y-DOTATOC was given in 3 cycles 6-8 wk apart. In the first cycle of therapy, adults received 4.4 GBq and children received 1.85 GBq/m2; the subsequent administered activities were adjusted according to the dosimetry of the preceding cycle so as not to exceed a total kidney dose of 23 Gy and bone marrow dose of 2 Gy. The radiation dose to the kidneys was determined from serial imaging sessions consisting of time-of-flight 90Y-DOTATOC PET/CT at 5 h after therapy and 90Y-DOTATOC bremsstrahlung SPECT/CT at 6, 24, 48, and 72 h. The PET/CT data were used to measure the absolute concentration of 90Y-DOTATOC and to calibrate the bremsstrahlung SPECT kidney clearance data. The radiation dose to the kidneys was determined by multiplying the time-integrated activity (from the fitted biexponential curve of renal clearance of 90Y-DOTATOC) with the energy emitted per decay, divided by the mass of the kidneys. Results: The radiation dose to the kidneys per cycle of 90Y-DOTATOC therapy was highly variable among patients, ranging from 0.32 to 3.0 mGy/MBq. In 17 (85%) of the 20 adult patients who received the second and the third treatment cycles of 90Y-DOTATOC, the administered activity was modified by at least 20% from the starting administered activity. Conclusion: Renal dosimetry of 90Y-DOTATOC is feasible using 90Y-DOTATOC time-of-flight PET/CT and bremsstrahlung SPECT/CT and has a significant impact on the administered activity in treatment cycles.


Asunto(s)
Tumores Neuroendocrinos/diagnóstico por imagen , Tumores Neuroendocrinos/radioterapia , Octreótido/análogos & derivados , Radiofármacos/uso terapéutico , Receptores de Somatostatina/metabolismo , Adolescente , Adulto , Anciano , Médula Ósea/diagnóstico por imagen , Médula Ósea/efectos de la radiación , Femenino , Humanos , Riñón/diagnóstico por imagen , Riñón/efectos de la radiación , Masculino , Persona de Mediana Edad , Tumores Neuroendocrinos/metabolismo , Octreótido/administración & dosificación , Octreótido/efectos adversos , Octreótido/uso terapéutico , Tomografía Computarizada por Tomografía de Emisión de Positrones , Medicina de Precisión , Estudios Prospectivos , Radiofármacos/administración & dosificación , Radiofármacos/efectos adversos , Dosificación Radioterapéutica , Tomografía Computarizada por Tomografía Computarizada de Emisión de Fotón Único , Adulto Joven , Radioisótopos de Itrio/administración & dosificación , Radioisótopos de Itrio/efectos adversos , Radioisótopos de Itrio/uso terapéutico
4.
AAPS J ; 20(1): 15, 2017 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-29218424

RESUMEN

To illustrate the use of imaging to quantify the transfer of materials from the nasal cavity to other anatomical compartments, specifically, transfer to the brain using the thymidine analogue, [18F]fluorothymidine (FLT), and the glucose analogue, [18F]fluorodeoxyglucose (FDG). Anesthetized rats were administered FLT or FDG by intranasal instillation (IN) or tail-vein injection (IV). PET/CT imaging was performed for up to 60 min. Volumes-of-interest (VOIs) for the olfactory bulb (OB) and the remaining brain were created on the CT and transferred to the co-registered dynamic PET. Time-activity curves (TACs) were generated and compared. The disposition patterns were successfully visualized and quantified and differences in brain distribution patterns were observed. For FDG, the concentration was substantially higher in the OB than the brain only after IN administration. For FLT, the concentration was higher in the OB than the brain after both IN and IV and higher after IN than after IV administration at all times, whereas the concentration in the brain was higher after IN than after IV administration at early times only. Approximately 50 and 9% of the IN FDG and FLT doses, respectively, remained in the nasal cavity at 20 min post-administration. The initial phase of clearance was similar for both agents (t1/2 = 2.53 and 3.36 min) but the slow clearance phase was more rapid for FLT than FDG (t1/2 = 32.1 and 85.2 min, respectively). Pharmacoimaging techniques employing PET/CT can be successfully implemented to quantitatively investigate and compare the disposition of radiolabeled agents administered by a variety of routes.


Asunto(s)
Barrera Hematoencefálica , Didesoxinucleósidos/farmacocinética , Fluorodesoxiglucosa F18/farmacocinética , Tomografía de Emisión de Positrones , Administración Intranasal , Animales , Cavidad Nasal/metabolismo , Bulbo Olfatorio/metabolismo , Permeabilidad , Ratas , Ratas Sprague-Dawley
5.
J Virol ; 91(24)2017 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-29021401

RESUMEN

The human papillomavirus (HPV) replication cycle is tightly linked to epithelial cell differentiation. To examine HPV-associated changes in the keratinocyte transcriptome, RNAs isolated from undifferentiated and differentiated cell populations of normal, spontaneously immortalized keratinocytes (NIKS) and NIKS stably transfected with HPV16 episomal genomes (NIKS16) were compared using next-generation sequencing (RNA-Seq). HPV16 infection altered expression of 2,862 cellular genes. Next, to elucidate the role of keratinocyte gene expression in late events during the viral life cycle, RNA-Seq was carried out on triplicate differentiated populations of NIKS (uninfected) and NIKS16 (infected). Of the top 966 genes altered (>log2 = 1.8, 3.5-fold change), 670 genes were downregulated and 296 genes were upregulated. HPV downregulated many genes involved in epithelial barrier function, which involves structural resistance to the environment and immunity to infectious agents. For example, HPV infection repressed expression of the differentiated keratinocyte-specific pattern recognition receptor TLR7, the Langerhans cell chemoattractant CCL20, and proinflammatory cytokines interleukin 1α (IL-1α) and IL-1ß. However, the type I interferon regulator IRF1, kappa interferon (IFN-κ), and viral restriction factors (IFIT1, -2, -3, and -5, OASL, CD74, and RTP4) were upregulated. HPV infection abrogated gene expression associated with the physical epithelial barrier, including keratinocyte cytoskeleton, intercellular junctions, and cell adhesion. Quantitative PCR (qRT-PCR) and Western blotting confirmed changes in expression of seven of the most significantly altered mRNAs. Expression of three genes showed statistically significant changes during cervical disease progression in clinical samples. Taken together, the data indicate that HPV infection manipulates the differentiating keratinocyte transcriptome to create an environment conducive to productive viral replication and egress.IMPORTANCE HPV genome amplification and capsid formation take place in differentiated keratinocytes. The viral life cycle is intimately associated with host cell differentiation. Deep sequencing (RNA-Seq) of RNA from undifferentiated and differentiated uninfected and HPV16-positive keratinocytes showed that almost 3,000 genes were differentially expressed in keratinocytes due to HPV16 infection. Strikingly, the epithelial barrier function of differentiated keratinocytes, comprising keratinocyte immune function and cellular structure, was found to be disrupted. These data provide new insights into the virus-host interaction that is crucial for the production of infectious virus and reveal that HPV infection remodels keratinocytes for completion of the virus replication cycle.


Asunto(s)
Papillomavirus Humano 16/patogenicidad , Queratinocitos/citología , Infecciones por Papillomavirus/genética , Análisis de Secuencia de ARN/métodos , Displasia del Cuello del Útero/virología , Neoplasias del Cuello Uterino/virología , Células 3T3 , Animales , Diferenciación Celular , Línea Celular , Femenino , Regulación de la Expresión Génica , Redes Reguladoras de Genes , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Papillomavirus Humano 16/fisiología , Humanos , Queratinocitos/efectos de los fármacos , Queratinocitos/virología , Ratones , Neoplasias del Cuello Uterino/genética , Replicación Viral , Displasia del Cuello del Útero/genética
6.
J Nucl Med ; 58(7): 1054-1057, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28153957

RESUMEN

Localization of the site of the unknown primary tumor is critical for surgical treatment of patients presenting with neuroendocrine tumor (NET) with metastases. Methods: Forty patients with metastatic NET and unknown primary site underwent 68Ga-DOTATOC PET/CT in a single-site prospective study. The 68Ga-DOTATOC PET/CT was considered true-positive if the positive primary site was confirmed by histology or follow-up imaging. The scan was considered false-positive if no primary lesion was found corresponding to the 68Ga-DOTATOC-positive site. All negative scans for primary tumor were considered false-negative. A scan was classified unconfirmed if 68Ga-DOTATOC PET/CT suggested a primary, however, no histology was obtained and imaging follow-up was not confirmatory. Results: The true-positive, false-positive, false-negative, and unconfirmed rates for unknown primary tumor were 38%, 7%, 50%, and 5%, respectively. Conclusion:68Ga-DOTATOC PET/CT is an effective modality in the localization of unknown primary in patients with metastatic NET.


Asunto(s)
Neoplasias Primarias Desconocidas/diagnóstico por imagen , Tumores Neuroendocrinos/diagnóstico por imagen , Tumores Neuroendocrinos/secundario , Octreótido/análogos & derivados , Compuestos Organometálicos , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Primarias Desconocidas/patología , Tumores Neuroendocrinos/patología , Variaciones Dependientes del Observador , Radiofármacos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Adulto Joven
7.
Acta Crystallogr E Crystallogr Commun ; 72(Pt 11): 1521-1525, 2016 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-27840699

RESUMEN

The title salt, C2H8N+·C10H5O8-, was the unexpected product of an attempt to prepare a ZrIV metal-organic framework with benzene-1,2,4,5-tetra-carb-oxy-lic acid (1,2,4,5-H3B4C). In the reaction, the DMF solvent has been decarb-on-yl-ated, forming the di-methyl-ammonium cation, with one proton lost from the tetra-carb-oxy-lic acid. It is proposed that the ZrIV salt acts as a Tsotsi or robber, plundering CO from the DMF mol-ecule. The resulting salt crystallizes with two cations and two anions in the asymmetric unit. An intra-molecular hydrogen bond forms between a carb-oxy-lic acid substituent and the carboxyl-ate group of each of the monodeprotonated (1,2,4,5-H3B4C-) anions. In the crystal, an extensive array of O-H⋯O, N-H⋯O and C-H⋯O hydrogen bonds generates a three-dimensional network, with columns of cations and anions forming along the b axis.

8.
J Neuropsychiatry Clin Neurosci ; 28(2): 89-96, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26548655

RESUMEN

This study aimed to examine global and regional cerebral blood flow and amyloid burden in combat veterans with and without traumatic brain injury (TBI). Cerebral blood flow (in milliliters per minute per 100 mL) was measured by quantitative [(15)O]water, and amyloid burden was measured by [(11)C]PIB imaging. Mean global cerebral blood flow was significantly lower in veterans with TBI compared with non-TBI veterans. There were essentially no differences between groups for globally normalized regional cerebral blood flow. Amyloid burden did not differ between TBI and non-TBI veterans. Veterans who have suffered a TBI have significantly lower cerebral blood flow than non-TBI controls but did not manifest increased levels of amyloid, globally or regionally.


Asunto(s)
Amiloide/metabolismo , Lesiones Traumáticas del Encéfalo/fisiopatología , Encéfalo/fisiopatología , Circulación Cerebrovascular/fisiología , Veteranos , Adulto , Encéfalo/metabolismo , Lesiones Traumáticas del Encéfalo/metabolismo , Humanos , Masculino
9.
Pancreas ; 42(6): 937-43, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23587853

RESUMEN

OBJECTIVE: To evaluate the repeatability of gallium-68 1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetic (DOTA)-D-Phe1-Try3-octreotide (68Ga-DOTATOC) positron emission tomography (PET) in neuroendocrine tumors. METHODS: Five patients with neuroendocrine tumors were imaged with 68Ga-DOTATOC PET twice within 5 days. Maximum and mean standardized uptake values (SUVmax and SUVmean) and kinetic parameters (K-Patlak and K-influx) of target lesions were measured. The repeatability of these measurements was investigated. RESULTS: Forty-seven target lesions were identified on whole-body PET and 21 lesions on dynamic images. There was excellent repeatability with intraclass correlation coefficient of 0.99 for SUVmax, SUVmean, and K-Patlak, and 0.85 for K-influx. The median absolute percent differences and the interquartile ranges (IQR) between 2 scans for SUVmax and SUVmean were 7.4% (IQR, 14.1%) and 9.3% (IQR, 10.6%), respectively. The median absolute percent differences for K-Patlak and K-influx were 12.5% (IQR, 12.6%) and 29.9% (IQR, 22.4%), respectively. The SUVmax of target lesions did not differ by more than 25% between the 2 scans. CONCLUSIONS: 68Ga-DOTATOC PET imaging of neuroendocrine tumors is highly reproducible. A difference of more than 25% in SUVmax represents a change that is larger than the measurement error observed on repeated studies and should reflect a significant change in the biological character of the tumor.


Asunto(s)
Tumores Neuroendocrinos/diagnóstico , Octreótido/análogos & derivados , Compuestos Organometálicos , Tomografía de Emisión de Positrones/métodos , Adulto , Anciano , Femenino , Radioisótopos de Galio , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
10.
Appl Radiat Isot ; 76: 46-54, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23026223

RESUMEN

A new NaCl based method for preparation of gallium-68 labeled radiopharmaceuticals has been adapted for use with an automated gallium-68 generator system. The method was evaluated based on 56 preparations of [(68)Ga]DOTATOC and compared to a similar acetone-based approach. Advantages of the new NaCl approach include reduced preparation time (<15 min) and removal of organic solvents. The method produces high peptide-bound % (>97%), and specific activity (>40 MBq nmole(-1) [(68)Ga]DOTATOC) and is well-suited for clinical production of radiopharmaceuticals.


Asunto(s)
Radioisótopos de Galio , Marcaje Isotópico/métodos , Octreótido/análogos & derivados , Radiofármacos/síntesis química , Automatización , Octreótido/síntesis química , Generadores de Radionúclidos , Cloruro de Sodio , Programas Informáticos
11.
Occup Med (Lond) ; 62(7): 541-8, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22773656

RESUMEN

BACKGROUND: Sheep farmers often complain of acute ill-health, known colloquially as 'dipper's flu', immediately after treating sheep with pesticides. There have been few prospective epidemiological studies to determine it's nature and incidence. Aims To determine the nature and frequency of symptoms occurring in farmers treating sheep for ectoparasites. METHODS: In a longitudinal study, farmers who planned to treat their sheep for ectoparasites were recruited. Farmers kept a symptom diary for 7 days after starting pesticide treatment. Symptoms reported on days 1-6 were compared to those reported on day 7 via the McNemar's test and with previously published literature definitions of dipper's flu. A principal component analysis (PCA) was carried out on new symptoms occurring on days 1 and 2. RESULTS: Of 781 farmers recruited, 352 farmers (45%) completed the symptom diary. In the 7 days after starting pesticide treatment, symptom complex reporting typically peaked on day 2, but few farmers (7 or less; <2%) were identified as having dipper's flu using literature definitions. However, PCA identified two new patterns of symptom complexes that accounted for 35% of the variance. A pyrexial factor consisted of four symptom complexes (feeling generally ill; feeling sweaty, shivery, feverish, hot or cold; feeling unusually tired; and having a headache) and a respiratory factor consisted of three symptom complexes (runny, stuffy, blocked or irritated nose; cough, shortness of breath or wheeze; and eye irritation). CONCLUSIONS: Existing definitions of dipper's flu do not adequately describe symptoms that occur following the treatment of sheep for ectoparasites.


Asunto(s)
Enfermedades de los Trabajadores Agrícolas/inducido químicamente , Enfermedades Profesionales/inducido químicamente , Exposición Profesional/efectos adversos , Plaguicidas/envenenamiento , Enfermedades de las Ovejas/prevención & control , Enfermedad Aguda , Adulto , Enfermedades de los Trabajadores Agrícolas/epidemiología , Enfermedades de los Trabajadores Agrícolas/fisiopatología , Crianza de Animales Domésticos , Animales , Femenino , Humanos , Incidencia , Masculino , Enfermedades Profesionales/epidemiología , Estudios Prospectivos , Ovinos , Enfermedades de las Ovejas/epidemiología , Enfermedades de las Ovejas/parasitología , Oveja Doméstica/parasitología , Encuestas y Cuestionarios
12.
Vet Rec ; 170(10): 259, 2012 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-22331501

RESUMEN

In a survey, 457 badgers that had been found dead in Wales were postmortem-examined, and samples were examined by histology and by extended culture (for up to 12 weeks). Mycobacterium bovis was cultured from 55 badgers (12.0 per cent), and the histology typical of M bovis infection was seen in a further six (1.3 per cent). The prevalence in badgers in each of 10 geographical areas varied between 0 and 26 per cent (P<0.001), and was associated with the incidence of confirmed M bovis infection in cattle herds in the same areas (P<0.01). In northern Wales, bTB was rare in both hosts. An infected badger was 12.3 times more likely to be within 5 km of a confirmed cattle bTB breakdown than an uninfected badger. The M bovis isolates from badgers belonged to one of four genotypes defined by spoligotype and variable number tandem repeat type. These genotypes were also found in 290 concurrent confirmed herd breakdowns, and tended to be similar to the genotypes in badgers in the same geographical areas. When badgers and cattle no more than 30 km apart were compared, the genotype diversity was greater in cattle than in badgers (P=0.016), suggesting that the movement of cattle plays a greater part in the spatial distribution of M bovis than the movement of badgers.


Asunto(s)
Mustelidae/microbiología , Mycobacterium bovis/aislamiento & purificación , Vigilancia de Guardia/veterinaria , Tuberculosis Bovina/microbiología , Animales , Bovinos , Femenino , Genotipo , Masculino , Mycobacterium bovis/genética , Regulación de la Población , Densidad de Población , Prevalencia , Tuberculosis Bovina/epidemiología , Reino Unido/epidemiología
13.
Clin Oncol (R Coll Radiol) ; 22(7): 570-7, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20650619

RESUMEN

AIMS: Patients with locally advanced pancreatic cancer (LAPC) are most commonly managed with chemotherapy or concurrent chemoradiotherapy (CRT), which may or may not include non-involved regional lymph nodes in the clinical target volume. We present our results of CRT for LAPC using capecitabine and delivering radiotherapy to a limited radiation field that excluded non-involved regional lymph nodes from the clinical target volume. MATERIALS AND METHODS: Thirty patients were studied. Patients received 50.4 Gy external beam radiotherapy in 28 fractions, delivered to a planning target volume expanded from the primary tumour and involved nodes only. Capecitabine (500-600 mg/m2) was given twice daily continuously during radiotherapy. Toxicity and efficacy data were prospectively collected. RESULTS: Nausea, vomiting and tumour pain were the most common grade 2 toxicities. One patient developed grade 3 nausea. The median time to progression was 8.8 months, with 20% remaining progression free at 1 year. The median overall survival was 9.7 months with a 1 year survival of 30%. Of 21 patients with imaged progression, 13 (62%) progressed systemically, three (14%) had local progression, two (10%) had locoregional progression and three (14%) progressed with both local/locoregional and systemic disease. CONCLUSION: CRT using capecitabine and limited field radiotherapy is a well-tolerated, relatively efficacious treatment for LAPC. The low toxicity and low regional progression rates support the use of limited field radiotherapy, allowing evaluation of this regimen with other anti-cancer agents.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/radioterapia , Antimetabolitos Antineoplásicos/uso terapéutico , Desoxicitidina/análogos & derivados , Fluorouracilo/análogos & derivados , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/radioterapia , Profármacos/uso terapéutico , Adenocarcinoma/patología , Anciano , Anciano de 80 o más Años , Capecitabina , Terapia Combinada , Desoxicitidina/uso terapéutico , Progresión de la Enfermedad , Femenino , Fluorouracilo/uso terapéutico , Humanos , Masculino , Dosis Máxima Tolerada , Persona de Mediana Edad , Neoplasias Pancreáticas/patología , Estudios Prospectivos , Dosificación Radioterapéutica , Tasa de Supervivencia , Resultado del Tratamiento
14.
Cancer Biother Radiopharm ; 25(3): 361-3, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20578842

RESUMEN

The purpose of this study was to evaluate the consistency of 3'-deoxy-3'[(18)F]fluorothymidine (FLT) standardized uptake values (SUVs) over the time course of imaging in head and neck cancer. Thirteen (13) subjects (all male; age: 56.9 +/- 6.7 years) with squamous cell head and neck cancer, stage III/IV, were administered FLT and imaged dynamically for 1 hour over the tumor and then underwent whole-body (WB) imaging commencing at 74 +/- 6 minutes. Imaging was repeated after 5 days of radiotherapy (10 Gy) and a single course of platinum-based chemotherapy. Volumes-of-interest (VOIs) were created on the last dynamic frame (SUV(60)). The pretherapy WB and midtherapy images were coregistered to the dynamic sequence and VOIs were applied. Mean and maximum SUVs (SUV(60) and SUV(WB)) and the change with treatment were evaluated. The correlations (Spearman's rho) between SUV(60) and SUV(WB) for all VOIs (pre- and midtherapy, n = 108 data pairs) were 0.98 for mean and 0.97 for maximum SUVs (p < 0.0001). Average absolute differences between SUV(60) and SUV(WB) were 0.18 +/- 0.15 and 0.29 +/- 0.32 SUV units, respectively. Correlations (Spearman's rho) between the change in SUV with therapy were 0.90 for mean and 0.89 for maximum SUV (p < 0.0001), with differences in the change values averaging 0.03 +/- 0.36 and -0.17 +/- 0.57 units, respectively. FLT SUVs are stable and comparable for images initiated between 55 and 100 minutes postinjection whether acquired pre- or midtherapy in head and neck cancer.


Asunto(s)
Didesoxinucleósidos/farmacocinética , Neoplasias de Cabeza y Cuello/diagnóstico , Neoplasias de Cabeza y Cuello/metabolismo , Tomografía de Emisión de Positrones , Radiofármacos/farmacocinética , Anciano , Carboplatino/uso terapéutico , Cisplatino/uso terapéutico , Didesoxinucleósidos/administración & dosificación , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Neoplasias de Cabeza y Cuello/radioterapia , Humanos , Masculino , Persona de Mediana Edad , Paclitaxel/uso terapéutico , Radiofármacos/administración & dosificación , Factores de Tiempo
15.
Nucl Med Biol ; 37(4): 433-8, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20447554

RESUMEN

INTRODUCTION: The kinetics of the bone marrow uptake of 3'-deoxy-3'-[(18)F]fluorothymidine (FLT) before and early after initiation of chemoradiation therapy was investigated in patients with head and neck cancer. METHODS: Fourteen subjects with head and neck cancer underwent FLT positron emission tomography (PET) at baseline and after 10 Gy of radiation therapy. Thirteen subjects also received one cycle of platinum-based chemotherapy before the second FLT PET. Kinetic parameters, including the flux constant based on compartmental analysis (K(FLT)) and the Patlak constant (K(Patlak)) for cervical marrow, were calculated. Standardized uptake values (SUVs) for the cervical marrow (inside the radiation field) and lumbar spine marrow (outside the radiation field) were also determined. RESULTS: There was a significant drop in FLT uptake in the bone marrow inside the radiation field. Mean pretreatment uptake values for the cervical spine were SUV=3.08+/-0.66, K(FLT)=0.045+/-0.016 min(-1) and K(Patlak)=0.039+/-0.013 min(-1). After treatment, these values were SUV=0.74+/-0.19, K(FLT)=0.011+/-0.005 min(-1) and K(Patlak)=0.005+/-0.002 min(-1). Compartmental analysis revealed a significant drop in k(3) in irradiated cervical marrow. FLT uptake in the bone marrow outside the radiation field exhibited a significantly smaller decrease. CONCLUSIONS: There is a marked decrease in FLT uptake in irradiated bone marrow after 10 Gy of radiation therapy to the head and neck. The drop in FLT uptake in irradiated marrow is due to a significant decrease in the net phosphorylation rate of FLT.


Asunto(s)
Médula Ósea/metabolismo , Didesoxinucleósidos/farmacocinética , Neoplasias de Cabeza y Cuello/metabolismo , Neoplasias de Cabeza y Cuello/terapia , Médula Ósea/diagnóstico por imagen , Médula Ósea/patología , Femenino , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Neoplasias de Cabeza y Cuello/radioterapia , Humanos , Masculino , Persona de Mediana Edad , Tomografía de Emisión de Positrones , Factores de Tiempo
16.
Water Sci Technol ; 61(5): 1081-8, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20220228

RESUMEN

The concentrations of some important endocrine disrupting chemicals and pharmaceuticals after various stages of wastewater treatment were investigated. The endocrine disrupting chemicals included natural and synthetic estrogenic and androgenic steroids. The pharmaceuticals included a series of sulfonamide antibiotics and trimethoprim. The removal efficiency of a membrane bioreactor (MBR) was investigated and compared with a conventional activated sludge (CAS) system. Samples were analysed by liquid chromatography tandem mass spectrometry. Results showed that the MBR and CAS systems effectively removed steroidal estrogens and androgens, but only partially eliminated the target antibiotics from wastewater. The MBR was shown to be more effective than the CAS system which was possibly attributed to the high solid retention time and concentration of biosolids in the MBR. The results highlight the potential wider application of MBRs for the removal of trace chemical contaminants in wastewater and their potential for use as decentralised wastewater treatment systems.


Asunto(s)
Reactores Biológicos , Disruptores Endocrinos/aislamiento & purificación , Sistema Endocrino/efectos de los fármacos , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos , Antibacterianos/aislamiento & purificación , Cromatografía Liquida/métodos , Disruptores Endocrinos/química , Humanos , Espectrometría de Masas/métodos , Membranas Artificiales , Preparaciones Farmacéuticas/análisis , Aguas del Alcantarillado/química , Trimetoprim/aislamiento & purificación , Eliminación de Residuos Líquidos/métodos
17.
J Nucl Med ; 50(7): 1028-35, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19525472

RESUMEN

UNLABELLED: The purpose of this study was to investigate the kinetic behavior of 3'-deoxy-3'-(18)F-fluorothymidine ((18)F-FLT) before and early after initiation of chemoradiation therapy in patients with squamous cell head and neck cancer. METHODS: A total of 8 patients with head and neck cancer underwent (18)F-FLT PET scans (7 patients at baseline and after 5 d [10 Gy] of radiation therapy given with concomitant chemotherapy and 1 patient only at baseline). Dynamic PET images were obtained with concurrent arterial or venous blood sampling. Kinetic parameters including the flux constant of (18)F-FLT based on compartmental analysis (K-FLT), the Patlak influx constant (K-Patlak), and standardized uptake value (SUV) were calculated for the primary tumor and (18)F-FLT-avid cervical lymph nodes for all scans. RESULTS: Mean pretreatment values of uptake for the primary tumor and cervical nodes were 0.075 +/- 0.006 min(-1), 0.042 +/- 0.004 min(-1), and 3.4 +/- 0.5 (mean +/- SD) for K-FLT, K-Patlak, and SUV, respectively. After 10 Gy of radiation therapy, these values were 0.040 +/- 0.01 min(-1), 0.018 +/- 0.016 min(-1), and 1.8 +/- 1.1 for K-FLT, K-Patlak, and SUV, respectively. For all lesions seen on pretherapy and midtherapy scans, the correlation was 0.90 between K-FLT and K-Patlak, 0.91 between K-FLT and SUV, and 0.99 between K-Patlak and SUV. CONCLUSION: The initial (18)F-FLT uptake and change early after treatment in squamous head and neck tumors can be adequately characterized with SUV obtained at 45-60 min, which demonstrates excellent correlation with influx parameters obtained from compartmental and Patlak analyses.


Asunto(s)
Didesoxinucleósidos/farmacocinética , Neoplasias de Cabeza y Cuello/metabolismo , Neoplasias de Cabeza y Cuello/terapia , Modelos Biológicos , Radiofármacos/farmacocinética , Adulto , Quimioterapia Adyuvante , Terapia Combinada , Simulación por Computador , Femenino , Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Humanos , Cinética , Masculino , Tasa de Depuración Metabólica , Persona de Mediana Edad , Cintigrafía , Radioterapia Adyuvante
18.
Leukemia ; 23(5): 863-9, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19148140

RESUMEN

We previously reported that susceptibility to childhood B cell precursor ALL (BCP ALL) is associated with HLA-DPB1 alleles having glutamic acid (E) rather than lysine (K) in the P4 antigenic peptide-binding pocket. Clustering approximately 90% of DPB1 alleles into DPB69E (DP2, 6, 8) and DPB69K (DP1, 3, 4) supertypes revealed that DP2 and DP8 are associated with BCP ALL, but DP6 is also associated with non-BCP leukaemia. Here, we report that only one of seven alleles with the DP6 supertype (DPB1(*)0601) is associated with childhood leukaemia (leukaemia vs controls: odds ratio, 95% confidence interval [OR, CI]: 4.6, 2.0-10.4; corrected P=0.019), but not with childhood solid tumours or lymphomas. DPB1(*)0601 is also significantly associated with leukaemia subtypes, including BCP ALL, Pro-B ALL, T-ALL and AML. DPB1(*)0601 is significantly over-transmitted (76.9%) from parents to children with BCP ALL (OR; CI: 4.7; 1.01-22.2). Sequencing the coding region of DPB1(*)0601 revealed an exon 1-4 haplotype [T-DEAV-KIL-RVI] shared with DPB1(*)0301 and 0901, but no evidence of germline mutations in childhood leukaemia. These results suggest that the DPbeta0601 molecule may be functionally involved in childhood leukaemia. Analysis of peptide binding and T-cell activation by DPbeta0601-peptide complexes should help determine its role in childhood leukaemia causation.


Asunto(s)
Antígenos HLA-DP/genética , Haplotipos/genética , Leucemia Mieloide Aguda/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Alelos , Secuencia de Aminoácidos , Estudios de Casos y Controles , Niño , Susceptibilidad a Enfermedades , Antígenos HLA-DP/metabolismo , Cadenas beta de HLA-DP , Humanos , Recién Nacido , Leucemia Mieloide Aguda/metabolismo , Datos de Secuencia Molecular , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Homología de Secuencia de Aminoácido
19.
Osteoarthritis Cartilage ; 17(4): 464-72, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19008124

RESUMEN

OBJECTIVE: To identify differentially expressed microRNAs (miRNAs) in human osteoarthritic (OA) cartilage and bone tissue and to determine their relevance to chondrocyte function. METHODS: Cartilage and bone was obtained from OA patients who underwent total knee joint replacement surgery or from post-mortem patients with no previous history of OA. MiRNA expression was quantified by real-time PCR (RT-PCR). Functional pathway analysis of miRNA was performed using Ingenuity Pathway Analysis. Primary chondrocytes were isolated by collagenase digestion and transfected with miRNA mimics and miRNA inhibitors using cationic lipid. Tumour Necrosis Factor-alpha (TNF-alpha) and Matrix metalloprotease 13 (MMP13) protein levels were measured by Enzyme-Linked ImmunoSorbent Assay (ELISA). RESULTS: In total we identified 17 miRNA that showed greater than 4-fold differential expression between OA and normal cartilage, and 30 miRNA that showed greater than 4-fold differential expression in OA bone. Functional pathway analysis of the predicted gene targets for miR-9, miR-98, which were upregulated in both OA bone and cartilage tissue, and miR-146, which was downregulated in OA cartilage, suggested that these miRNA mediate inflammatory functions and pathways. Over-expression of miR-9, miR-98 or miR-146 in isolated human chondrocytes reduced interleukin-1 beta (IL-1 beta) induced TNF-alpha production. Furthermore, inhibition and over-expression of miR-9 modulated MMP13 secretion. CONCLUSIONS: We have identified a number of differentially expressed miRNAs in late-stage human OA cartilage and bone. Functional analysis of miR-9, miR-98 and miR-146 in primary chondrocytes suggests a role in mediating the IL-1 beta induced production of TNF-alpha. MiR-9, upregulated in OA tissue, was found to inhibit secretion of the collagen type II-targeting metalloproteinase MMP13 in isolated human chondrocytes.


Asunto(s)
Metaloproteinasa 13 de la Matriz/biosíntesis , MicroARNs/fisiología , Osteoartritis de la Rodilla/genética , Factor de Necrosis Tumoral alfa/biosíntesis , Anciano , Cartílago Articular/metabolismo , Cartílago Articular/patología , Células Cultivadas , Condrocitos/metabolismo , Biología Computacional/métodos , Perfilación de la Expresión Génica/métodos , Regulación de la Expresión Génica , Humanos , Mediadores de Inflamación/fisiología , MicroARNs/genética , Persona de Mediana Edad , Osteoartritis de la Rodilla/metabolismo , Osteoartritis de la Rodilla/patología , Transducción de Señal/genética , Transducción de Señal/fisiología
20.
Water Sci Technol ; 58(11): 2187-94, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-19092195

RESUMEN

There are limited studies on the fate and levels of endocrine disrupting chemicals in sewage treatment plants in Australia. Research undertaken in Europe and North America has shown biologically significant levels of both oestrogenic and androgenic chemicals in sewage effluent. The aim of this work was to determine the oestrogenic and androgenic activities of raw and treated sewage from sewage treatment plants run by MidCoast Water, New South Wales, Australia. Oestrogenic and androgenic activities were measured using a yeast screen bioassay. Results showed that the raw effluent contained biologically significant levels of both oestrogenic (0.58-2.91 ng/l) and androgenic (216-480 ng/l) activities. Androgenic activity was significantly higher than oestrogenic activity, which was consistent with other Australian studies and was attributed to the higher levels of androgens in domestic waste from human excretion compared to oestrogens. Secondary treatment (using activated sludge) removed the majority of the oestrogenic and androgenic activity (up to 99%). Tertiary treatment by UV removed varying levels of oestrogenic (19-69%) and androgenic (5-55%) activities. A Membrane Bioreactor (MBR) at one of the STPs, which consists of an MBR followed by electrochlorination removed over 87% of the oestrogenic activity and over 98% of androgenic activity from raw sewage samples. However, levels which could be biologically significant still remained after secondary and tertiary treatment (>0.1 ng/l oestrogenic activity and >1 ng/l androgenic activity).


Asunto(s)
Disruptores Endocrinos/análisis , Monitoreo del Ambiente/métodos , Aguas del Alcantarillado , Purificación del Agua/instrumentación , Andrógenos/análisis , Australia , Estrógenos/análisis
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